Enhanced Light-Driven Antimicrobial Activity of Cationic Poly (oxanorbornene) s by Phthalocyanine Incorporation into Polymer as Pendants
- Ahmetali, Erem, Sen, Pinar, Süer, N Ceren, Aksu, Burak, Nyokong, Tebello, Eren, Tarik, Sener, Kasim M
- Authors: Ahmetali, Erem , Sen, Pinar , Süer, N Ceren , Aksu, Burak , Nyokong, Tebello , Eren, Tarik , Sener, Kasim M
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185976 , vital:44453 , xlink:href=" https://doi.org/10.1002/macp.202000386"
- Description: Amphiphilic poly(oxanorbornene)s are promising synthetic polymers that mimic the structural properties and antimicrobial functions of naturally occurring antimicrobial peptides. Here, poly(oxanorbornene)s bearing pendant zinc(II) phthalocyanine and triphenyl(ethyl) phosphonium functionalities are synthesized by ring-opening metathesis polymerization (ROMP). Fluorescence, singlet oxygen and triplet quantum yields of polymers are measured in dimethyl sulfoxide and aqueous medium. The singlet oxygen quantum yields of copolymers with the highest triphenyl and triethyl phosphonium content are found to be 0.29 and 0.41, respectively. Then, antimicrobial activities of polymers against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) are investigated under both dark and light conditions. Synergistic effect of zinc(II) phthalocyanine and phosphonium-containing poly(oxanorbornene) is observed that the conjugate possessing the most triphenyl phosphonium side chains has the highest activity under light against both gram-positive and gram-negative bacterial strains after 80 min irradiation, reducing the survival of E. coli or S. aureus by 99.9999%. Hemolytic concentrations of the copolymers are found between 8 and 512 µg mL−1. Scanning electron microscopy (SEM) proves that the bacteria membrane deforms after contacting with the biocidal polymer.
- Full Text:
- Date Issued: 2020
- Authors: Ahmetali, Erem , Sen, Pinar , Süer, N Ceren , Aksu, Burak , Nyokong, Tebello , Eren, Tarik , Sener, Kasim M
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185976 , vital:44453 , xlink:href=" https://doi.org/10.1002/macp.202000386"
- Description: Amphiphilic poly(oxanorbornene)s are promising synthetic polymers that mimic the structural properties and antimicrobial functions of naturally occurring antimicrobial peptides. Here, poly(oxanorbornene)s bearing pendant zinc(II) phthalocyanine and triphenyl(ethyl) phosphonium functionalities are synthesized by ring-opening metathesis polymerization (ROMP). Fluorescence, singlet oxygen and triplet quantum yields of polymers are measured in dimethyl sulfoxide and aqueous medium. The singlet oxygen quantum yields of copolymers with the highest triphenyl and triethyl phosphonium content are found to be 0.29 and 0.41, respectively. Then, antimicrobial activities of polymers against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) are investigated under both dark and light conditions. Synergistic effect of zinc(II) phthalocyanine and phosphonium-containing poly(oxanorbornene) is observed that the conjugate possessing the most triphenyl phosphonium side chains has the highest activity under light against both gram-positive and gram-negative bacterial strains after 80 min irradiation, reducing the survival of E. coli or S. aureus by 99.9999%. Hemolytic concentrations of the copolymers are found between 8 and 512 µg mL−1. Scanning electron microscopy (SEM) proves that the bacteria membrane deforms after contacting with the biocidal polymer.
- Full Text:
- Date Issued: 2020
Photodynamic therapy activities of phthalocyanine-based macromolecular photosensitizers on MCF-7 breast cancer cells
- Ahmetali, Erem, Sen, Pinar, Süer, N Ceren, Nyokong, Tebello, Erin, Tarik, Sener, M Kasim
- Authors: Ahmetali, Erem , Sen, Pinar , Süer, N Ceren , Nyokong, Tebello , Erin, Tarik , Sener, M Kasim
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185655 , vital:44407 , xlink:href="https://doi.org/10.1080/10601325.2021.1934012"
- Description: Poly(oxanorbornene)s with zinc(II) phthalocyanine side chains have been synthesized by ring-opening metathesis polymerization. The incorporation of zinc(II) phthalocyanine into cationic polymer has given poly(oxanorbornene)s noteworthy photophysicochemical properties and the capacity to generate singlet oxygen under light irradiation. To investigate photosensitizer’s properties of the newly synthesized polymers P6 and P7: fluorescence (ΦF), singlet oxygen (ΦΔ) and triplet (ΦT) quantum yields of polymers have been measured in dimethyl sulfoxide and aqueous medium. Singlet oxygen quantum yields of P6 and P7 have been found to be 0.22 and 0.20 in dimethyl sulfoxide, respectively. Then, photodynamic therapy activities of polymers (P1-P7) against human breast adenocarcinoma cell line (MCF-7 cells) have been investigated. The copolymer P5 bearing pendant zinc(II) phthalocyanine and triethyl phosphonium functionalities has showed enhanced PDT activity with less than 10% viable cells at 60 μg/mL.
- Full Text:
- Date Issued: 2021
- Authors: Ahmetali, Erem , Sen, Pinar , Süer, N Ceren , Nyokong, Tebello , Erin, Tarik , Sener, M Kasim
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185655 , vital:44407 , xlink:href="https://doi.org/10.1080/10601325.2021.1934012"
- Description: Poly(oxanorbornene)s with zinc(II) phthalocyanine side chains have been synthesized by ring-opening metathesis polymerization. The incorporation of zinc(II) phthalocyanine into cationic polymer has given poly(oxanorbornene)s noteworthy photophysicochemical properties and the capacity to generate singlet oxygen under light irradiation. To investigate photosensitizer’s properties of the newly synthesized polymers P6 and P7: fluorescence (ΦF), singlet oxygen (ΦΔ) and triplet (ΦT) quantum yields of polymers have been measured in dimethyl sulfoxide and aqueous medium. Singlet oxygen quantum yields of P6 and P7 have been found to be 0.22 and 0.20 in dimethyl sulfoxide, respectively. Then, photodynamic therapy activities of polymers (P1-P7) against human breast adenocarcinoma cell line (MCF-7 cells) have been investigated. The copolymer P5 bearing pendant zinc(II) phthalocyanine and triethyl phosphonium functionalities has showed enhanced PDT activity with less than 10% viable cells at 60 μg/mL.
- Full Text:
- Date Issued: 2021
The photophysicochemical properties and photodynamic therapy activity of Schiff base substituted phthalocyanines doped into silica nanoparticles and conjugated to folic acid
- Magadla, Aviwe, Babu, Balaji, Sen, Pinar, Nyokong, Tebello
- Authors: Magadla, Aviwe , Babu, Balaji , Sen, Pinar , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185407 , vital:44384 , xlink:href="https://doi.org/10.1016/j.poly.2021.115227"
- Description: This work explores the synthesis, photophysicochemical properties and photodynamic activity (PDT) of tetrakis [N,N’–bis (4-(diethylamino)benzylidene) amino)propan-2-yl)oxy) phthalocyaninato] Zn (II) (3) and tetra-phenoxy N,N-dimethyl-4-((methylimino) Zn (II) (4) when the encapsulated into silica nanoparticles (SiNPs) followed by conjugation of folic acid (FA). The synthesised complexes and their doped analogues are examined for their PDT activity using MCF-7 cells. All the complexes showed dark toxicity that is >80%. The folic acid conjugates, MPc@SiNPs-FA showed greater photocytoxicity against MCF-7 cells upon irradiation with laser light.
- Full Text:
- Date Issued: 2021
- Authors: Magadla, Aviwe , Babu, Balaji , Sen, Pinar , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185407 , vital:44384 , xlink:href="https://doi.org/10.1016/j.poly.2021.115227"
- Description: This work explores the synthesis, photophysicochemical properties and photodynamic activity (PDT) of tetrakis [N,N’–bis (4-(diethylamino)benzylidene) amino)propan-2-yl)oxy) phthalocyaninato] Zn (II) (3) and tetra-phenoxy N,N-dimethyl-4-((methylimino) Zn (II) (4) when the encapsulated into silica nanoparticles (SiNPs) followed by conjugation of folic acid (FA). The synthesised complexes and their doped analogues are examined for their PDT activity using MCF-7 cells. All the complexes showed dark toxicity that is >80%. The folic acid conjugates, MPc@SiNPs-FA showed greater photocytoxicity against MCF-7 cells upon irradiation with laser light.
- Full Text:
- Date Issued: 2021
The antibacterial and antifungal properties of neutral, octacationic and hexadecacationic Zn phthalocyanines when conjugated to silver nanoparticles
- Mapukata, Sibusisiwe, Sen, Pinar, Osifeko, Olawale L, Nyokong, Tebello
- Authors: Mapukata, Sibusisiwe , Sen, Pinar , Osifeko, Olawale L , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185667 , vital:44408 , xlink:href="https://doi.org/10.1016/j.pdpdt.2021.102361"
- Description: The syntheses and characterization of novel octacationic and hexadecacationic Pcs is reported. With the aim of enhancing singlet oxygen generation efficiencies and hence antimicrobial activities, these Pcs (including their neutral counterpart) are conjugated to Ag nanoparticles (AgNPs). The obtained results show that the conjugate composed of the neutral Pc has a higher loading of Pcs as well as a greater singlet oxygen quantum yield enhancement (in the presence of AgNPs) in DMSO. The antimicrobial efficiencies of the Pcs and their conjugates were evaluated and compared on S. aureus, E. coli and C. albicans. The cationic Pcs possess better activity than the neutral Pc against all the microorganisms with the hexadecacationic Pc being the best. This work therefore demonstrates that increase in the number of cationic charges on the reported Pcs results in enhanced antimicrobial activities, which is maintained even when conjugated to Ag nanoparticles. The high activity and lack of selectivity of the cationic Pcs when conjugated to Ag NPs against different microorganisms make them good candidates for real life antimicrobial treatments.
- Full Text:
- Date Issued: 2021
- Authors: Mapukata, Sibusisiwe , Sen, Pinar , Osifeko, Olawale L , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185667 , vital:44408 , xlink:href="https://doi.org/10.1016/j.pdpdt.2021.102361"
- Description: The syntheses and characterization of novel octacationic and hexadecacationic Pcs is reported. With the aim of enhancing singlet oxygen generation efficiencies and hence antimicrobial activities, these Pcs (including their neutral counterpart) are conjugated to Ag nanoparticles (AgNPs). The obtained results show that the conjugate composed of the neutral Pc has a higher loading of Pcs as well as a greater singlet oxygen quantum yield enhancement (in the presence of AgNPs) in DMSO. The antimicrobial efficiencies of the Pcs and their conjugates were evaluated and compared on S. aureus, E. coli and C. albicans. The cationic Pcs possess better activity than the neutral Pc against all the microorganisms with the hexadecacationic Pc being the best. This work therefore demonstrates that increase in the number of cationic charges on the reported Pcs results in enhanced antimicrobial activities, which is maintained even when conjugated to Ag nanoparticles. The high activity and lack of selectivity of the cationic Pcs when conjugated to Ag NPs against different microorganisms make them good candidates for real life antimicrobial treatments.
- Full Text:
- Date Issued: 2021
Photodegradation of tetracycline by asymmetrical zinc (II) phthalocyanines conjugated to cobalt tungstate nanoparticles
- Mgidlana, Sithi, Sen, Pinar, Nyokong, Tebello
- Authors: Mgidlana, Sithi , Sen, Pinar , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/300233 , vital:57908 , xlink:href="https://doi.org/10.1016/j.molstruc.2022.132938"
- Description: This work focused on syntheses of novel asymmetrically tetra substituted Zn phthalocyanines (ZnPc) each containing a single carboxyl group, with the other substituents bearing alkynyl (complex 1) and fluorine containing groups (complexes 2 and 3). The complexes were conjugated to cobalt tungstate nanoparticles and employed as efficient photocatalysts for degradation of tetracycline in water. ZnPc complexes and their conjugates showed good photophysical and photochemical properties behaviour with complex 1 giving higher triplet and singlet oxygen quantum yields compared to 2 and 3. Complex 1 showed higher activity towards the photodegradation of tetracycline compared to complexes 2 and 3, with higher kobs and initial rates for the former. The photocatalysis obeyed the Langmuir-Hinshelwood kinetic model.
- Full Text:
- Date Issued: 2022
- Authors: Mgidlana, Sithi , Sen, Pinar , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/300233 , vital:57908 , xlink:href="https://doi.org/10.1016/j.molstruc.2022.132938"
- Description: This work focused on syntheses of novel asymmetrically tetra substituted Zn phthalocyanines (ZnPc) each containing a single carboxyl group, with the other substituents bearing alkynyl (complex 1) and fluorine containing groups (complexes 2 and 3). The complexes were conjugated to cobalt tungstate nanoparticles and employed as efficient photocatalysts for degradation of tetracycline in water. ZnPc complexes and their conjugates showed good photophysical and photochemical properties behaviour with complex 1 giving higher triplet and singlet oxygen quantum yields compared to 2 and 3. Complex 1 showed higher activity towards the photodegradation of tetracycline compared to complexes 2 and 3, with higher kobs and initial rates for the former. The photocatalysis obeyed the Langmuir-Hinshelwood kinetic model.
- Full Text:
- Date Issued: 2022
Direct nonlinear optical absorption measurements of asymmetrical zinc (II) phthalocyanine when covalently linked to semiconductor quantum dots
- Mgidlana, Sithi, Sen, Pinar, Nyokong, Tebello
- Authors: Mgidlana, Sithi , Sen, Pinar , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186056 , vital:44459 , xlink:href="https://doi.org/10.1016/j.molstruc.2020.128729"
- Description: We report on nonlinear optical properties of tris[(4-tert-butyl)-2-thio (phenyl)acetic acid (1) and tris(dimethyl-5-(3,4-phenoxy) isophthalate (2) phthalocyaninato zinc (II) complexes. The synthesized complexes were covalently conjugated to glutathione-capped CdTe/ZnSe/ZnO quantum dots. We observed an increase in triplet quantum yield with corresponding decrease in fluorescence quantum yield of conjugates compared to Pc complexes alone. Z-scan technique was employed to experimentally test the nonlinear optical response of complexes and nanoconjugates in solution at laser excitation wavelength of 532 nm with 7 ns pulse. Nonlinear absorption coefficient, third-order optical susceptibility and optical limiting threshold of the materials were obtained from the Z-scan data. The nonlinear absorption parameters improved in the presence of CdTe/ZnSe/ZnO, with 1 and 1-CdTe/ZnSe/ZnO, giving the best results due to the presence of electron donating substituents.
- Full Text:
- Date Issued: 2020
- Authors: Mgidlana, Sithi , Sen, Pinar , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186056 , vital:44459 , xlink:href="https://doi.org/10.1016/j.molstruc.2020.128729"
- Description: We report on nonlinear optical properties of tris[(4-tert-butyl)-2-thio (phenyl)acetic acid (1) and tris(dimethyl-5-(3,4-phenoxy) isophthalate (2) phthalocyaninato zinc (II) complexes. The synthesized complexes were covalently conjugated to glutathione-capped CdTe/ZnSe/ZnO quantum dots. We observed an increase in triplet quantum yield with corresponding decrease in fluorescence quantum yield of conjugates compared to Pc complexes alone. Z-scan technique was employed to experimentally test the nonlinear optical response of complexes and nanoconjugates in solution at laser excitation wavelength of 532 nm with 7 ns pulse. Nonlinear absorption coefficient, third-order optical susceptibility and optical limiting threshold of the materials were obtained from the Z-scan data. The nonlinear absorption parameters improved in the presence of CdTe/ZnSe/ZnO, with 1 and 1-CdTe/ZnSe/ZnO, giving the best results due to the presence of electron donating substituents.
- Full Text:
- Date Issued: 2020
Dual action of asymmetrical zinc (II) phthalocyanines conjugated to silver tungstate nanoparticles towards photodegradation of tetracycline and inactivation of Staphylococcus aureus bacteria
- Mgidlana, Sithi, Sen, Pinar, Nyokong, Tebello
- Authors: Mgidlana, Sithi , Sen, Pinar , Nyokong, Tebello
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/360400 , vital:65085 , xlink:href="https://doi.org/10.1016/j.jphotochem.2022.114444"
- Description: Asymmetric (A3B) Zn(II) phthalocyanines containing dimethoxy phenoxy as the dominant substituent and (phenoxy) propanoic acid (1), (phenoxy) acetic acid (2), and (phenoxy) acrylic acid (3) as the other substituents were synthesized and linked to silver tungstate nanoparticles (Ag2WO4 NPs). The photocatalytic activities of the prepared complexes 1–3 and nanoconjugates were evaluated for the photodegradation of tetracycline (TC) under visible-light irradiation and for photodynamic antimicrobial chemotherapy (PACT) activity against S. aureus. The results revealed that complex 3 had the best photocatalytic and PACT performance compared to 1 and 2, corresponding to the higher singlet oxygen quantum yield of the former in dimethyl sulfoxide. The photodegradation reaction was also examined using EPR and a mechanism for generation of singlet oxygen under visible light was confirmed. Photoinactivation of S. aureus improved in the presence of TC, when the two are applied together.
- Full Text:
- Date Issued: 2023
- Authors: Mgidlana, Sithi , Sen, Pinar , Nyokong, Tebello
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/360400 , vital:65085 , xlink:href="https://doi.org/10.1016/j.jphotochem.2022.114444"
- Description: Asymmetric (A3B) Zn(II) phthalocyanines containing dimethoxy phenoxy as the dominant substituent and (phenoxy) propanoic acid (1), (phenoxy) acetic acid (2), and (phenoxy) acrylic acid (3) as the other substituents were synthesized and linked to silver tungstate nanoparticles (Ag2WO4 NPs). The photocatalytic activities of the prepared complexes 1–3 and nanoconjugates were evaluated for the photodegradation of tetracycline (TC) under visible-light irradiation and for photodynamic antimicrobial chemotherapy (PACT) activity against S. aureus. The results revealed that complex 3 had the best photocatalytic and PACT performance compared to 1 and 2, corresponding to the higher singlet oxygen quantum yield of the former in dimethyl sulfoxide. The photodegradation reaction was also examined using EPR and a mechanism for generation of singlet oxygen under visible light was confirmed. Photoinactivation of S. aureus improved in the presence of TC, when the two are applied together.
- Full Text:
- Date Issued: 2023
Investigation of electrocatalytic behaviour of low symmetry cobalt phthalocyanines when clicked to azide grafted carbon electrodes
- Mpeta, Lakethe S, Sen, Pinar, Nyokong, Tebello
- Authors: Mpeta, Lakethe S , Sen, Pinar , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186304 , vital:44483 , xlink:href="https://doi.org/10.1016/j.jelechem.2020.113896"
- Description: This work describes the electrochemical properties of low symmetry cobalt phthalocyanines namely, tris-[(4-tert-butylphenoxy)-4-(pent-4-yn-1-yloxy) phthalocyaniato] cobalt (II) (3) and tris-[(4-tert-butylphenoxy)-4-(4-ethybylbenzyl-oxy) phthalocyaniato] cobalt (II) (5). The complexes were characterized by a number of techniques including UV–Vis, mass, and infrared spectra, as well as elemental analysis. The glassy carbon electrodes were first azide functionalized then clicked to low symmetry phthalocyanines. The click reaction was confirmed using X-ray photoelectron spectra. The constructed electrodes showed excellent electrocatalytic activity towards hydrazine oxidation. Oxidation peaks with low potentials of 0.21 V and 0.26 V, for complexes 3 and 5, respectively were obtained. Complex-5 gave a better detection limit of 0.94 μM and electrocatalytic rate constant of 5.6 × 106 M−1 s−1.
- Full Text:
- Date Issued: 2020
- Authors: Mpeta, Lakethe S , Sen, Pinar , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186304 , vital:44483 , xlink:href="https://doi.org/10.1016/j.jelechem.2020.113896"
- Description: This work describes the electrochemical properties of low symmetry cobalt phthalocyanines namely, tris-[(4-tert-butylphenoxy)-4-(pent-4-yn-1-yloxy) phthalocyaniato] cobalt (II) (3) and tris-[(4-tert-butylphenoxy)-4-(4-ethybylbenzyl-oxy) phthalocyaniato] cobalt (II) (5). The complexes were characterized by a number of techniques including UV–Vis, mass, and infrared spectra, as well as elemental analysis. The glassy carbon electrodes were first azide functionalized then clicked to low symmetry phthalocyanines. The click reaction was confirmed using X-ray photoelectron spectra. The constructed electrodes showed excellent electrocatalytic activity towards hydrazine oxidation. Oxidation peaks with low potentials of 0.21 V and 0.26 V, for complexes 3 and 5, respectively were obtained. Complex-5 gave a better detection limit of 0.94 μM and electrocatalytic rate constant of 5.6 × 106 M−1 s−1.
- Full Text:
- Date Issued: 2020
The effects of asymmetry in combination with reduced graphene oxide nanosheets on hydrazine electrocatalytic detection on cobalt phthalocyanines
- Mpeta, Lekhetho S, Sen, Pinar, Nyokong, Tebello
- Authors: Mpeta, Lekhetho S , Sen, Pinar , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186023 , vital:44456 , xlink:href="https://doi.org/10.1002/elan.202060094"
- Description: New symmetric {tetrakis [4-(4-(5-chloro-1Hbenzo[d]imidazol-2-yl) phenoxy phthalocyaninato] Co (II) (CoTPc)} and low symmetry {tris tert butyl phenoxy mono [4-(4-(5-chloro-1H-benzo[d]imidazol-2-yl) phenoxy phthalocyaninato]} Co (II) (CoMPc) were successfully synthesised and combined with reduced graphene oxide nanosheets (rGONS) for electrocatalytic detection of hydrazine. Prior to electrocatalysis, the probes were characterised using cyclic voltammetry and electrochemical impedance spectroscopy. Chronoamperometry was used to determine catalytic rate constant and the limit of detection (LOD). CoMPc-rGONS gave catalytic rate constant and LOD of 1.37×106 M 1 s 1 and 0.82 μM respectively, rendering it a more suitable probe for hydrazine, due to low symmetry.
- Full Text:
- Date Issued: 2020
- Authors: Mpeta, Lekhetho S , Sen, Pinar , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186023 , vital:44456 , xlink:href="https://doi.org/10.1002/elan.202060094"
- Description: New symmetric {tetrakis [4-(4-(5-chloro-1Hbenzo[d]imidazol-2-yl) phenoxy phthalocyaninato] Co (II) (CoTPc)} and low symmetry {tris tert butyl phenoxy mono [4-(4-(5-chloro-1H-benzo[d]imidazol-2-yl) phenoxy phthalocyaninato]} Co (II) (CoMPc) were successfully synthesised and combined with reduced graphene oxide nanosheets (rGONS) for electrocatalytic detection of hydrazine. Prior to electrocatalysis, the probes were characterised using cyclic voltammetry and electrochemical impedance spectroscopy. Chronoamperometry was used to determine catalytic rate constant and the limit of detection (LOD). CoMPc-rGONS gave catalytic rate constant and LOD of 1.37×106 M 1 s 1 and 0.82 μM respectively, rendering it a more suitable probe for hydrazine, due to low symmetry.
- Full Text:
- Date Issued: 2020
Development of manganese phthalocyanine decorated with silver nanoparticles nanocomposite for improved electrocatalytic oxidation of hydrazine:
- Mpeta, Lekhetho S, Sen, Pinar, Nyokong, Tebello
- Authors: Mpeta, Lekhetho S , Sen, Pinar , Nyokong, Tebello
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148472 , vital:38742 , https://doi.org/10.1016/j.jelechem.2020.114173
- Description: In this study we report on the synthesis of tetrakis [4-(4-(5-chloro-1H-benzo [d]imidazol-2-yl) phenoxy phthalocyaninato] manganese (III) chloride (MnPc). The MnPc was first used to modify a glassy carbon electrode, followed by the growth of silver nanoparticles (AgNPs) onto the MnPc modified electrode to form MnPc-AgNPs modified electrode. The modified electrode was characterized using cydic voltammetry, chronoamperometry, scanning electrochemical microscopy and electrochemical impedance spectroscopy. The modified MnPc-AgNPs electrode was employed for the detection of hydrazine. The MnPc-AgNPs gave better current responses for electrooxidation of hydrazine relative to MnPc and AgNPs, individually. The catalytic rate constant was 1.90 x 10(5 )M(-1) S-1, with the detection limit (LoD) of 2.42 pM (using 3 sigma notation), and sensitivity of 61.56 mu A mM(-1), for MnPc-AgNPs. (C) 2020 Elsevier B.V. All rights reserved.
- Full Text:
- Date Issued: 2020
- Authors: Mpeta, Lekhetho S , Sen, Pinar , Nyokong, Tebello
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148472 , vital:38742 , https://doi.org/10.1016/j.jelechem.2020.114173
- Description: In this study we report on the synthesis of tetrakis [4-(4-(5-chloro-1H-benzo [d]imidazol-2-yl) phenoxy phthalocyaninato] manganese (III) chloride (MnPc). The MnPc was first used to modify a glassy carbon electrode, followed by the growth of silver nanoparticles (AgNPs) onto the MnPc modified electrode to form MnPc-AgNPs modified electrode. The modified electrode was characterized using cydic voltammetry, chronoamperometry, scanning electrochemical microscopy and electrochemical impedance spectroscopy. The modified MnPc-AgNPs electrode was employed for the detection of hydrazine. The MnPc-AgNPs gave better current responses for electrooxidation of hydrazine relative to MnPc and AgNPs, individually. The catalytic rate constant was 1.90 x 10(5 )M(-1) S-1, with the detection limit (LoD) of 2.42 pM (using 3 sigma notation), and sensitivity of 61.56 mu A mM(-1), for MnPc-AgNPs. (C) 2020 Elsevier B.V. All rights reserved.
- Full Text:
- Date Issued: 2020
Electrochemical detection of dopamine using phthalocyanine-nitrogen-doped graphene quantum dot conjugates
- Ndebele Nobuhle, Sen, Pinar, Nyokong, Tebello
- Authors: Ndebele Nobuhle , Sen, Pinar , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185724 , vital:44418 , xlink:href="https://doi.org/10.1016/j.jelechem.2021.115111"
- Description: Two cobalt phthalocyanine molecules were synthesized, a symmetrically substituted CoPc (1) and an unsymmetrically substituted CoPc (2). These CoPcs were π-π stacked onto nitrogen-doped graphene quantum dots (NGQDs). The CoPcs, NGQDs and their respective conjugates were used as electro-catalytic probes in the electrochemical oxidation of dopamine. The molecules were adsorbed onto a glassy carbon electrode (GCE) using the drop dry method, the GCE was used to support those catalysts. The electrooxidation of dopamine was studied using cyclic voltammetry and chronoamperometry. An improvement in the sensitivity and limit of detection was observed upon conjugation.
- Full Text:
- Date Issued: 2021
- Authors: Ndebele Nobuhle , Sen, Pinar , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185724 , vital:44418 , xlink:href="https://doi.org/10.1016/j.jelechem.2021.115111"
- Description: Two cobalt phthalocyanine molecules were synthesized, a symmetrically substituted CoPc (1) and an unsymmetrically substituted CoPc (2). These CoPcs were π-π stacked onto nitrogen-doped graphene quantum dots (NGQDs). The CoPcs, NGQDs and their respective conjugates were used as electro-catalytic probes in the electrochemical oxidation of dopamine. The molecules were adsorbed onto a glassy carbon electrode (GCE) using the drop dry method, the GCE was used to support those catalysts. The electrooxidation of dopamine was studied using cyclic voltammetry and chronoamperometry. An improvement in the sensitivity and limit of detection was observed upon conjugation.
- Full Text:
- Date Issued: 2021
Electrocatalytic activity of Schiff base containing copper phthalocyanines towards the detection of catechol
- Ndebele, Nobuhle, Sen, Pinar, Nyokong, Tebello
- Authors: Ndebele, Nobuhle , Sen, Pinar , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231410 , vital:49885 , xlink:href="https://doi.org/10.1016/j.poly.2021.115518"
- Description: In this study, four new copper phthalocyanine complexes were synthesised and studied as electrocatalysts for the detection of catechol. Two of these complexes were derived from a symmetrical benzaldehyde phthalocyanine complex via the condensation of the benzaldehyde substituents with amine reagents. The electrocatalysts proved to be highly stable towards the detection of catechol. The oxidation peaks obtained using cyclic voltammetry range from 0.20 to 0.38 V. Detection limits were obtained via chronoamperometry and are as low as 0.16 µM with fairly high sensitives being obtained. Overall all four copper complexes exhibited excellent electrocatalytic activity towards the electrooxidation of catechol.
- Full Text:
- Date Issued: 2021
- Authors: Ndebele, Nobuhle , Sen, Pinar , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231410 , vital:49885 , xlink:href="https://doi.org/10.1016/j.poly.2021.115518"
- Description: In this study, four new copper phthalocyanine complexes were synthesised and studied as electrocatalysts for the detection of catechol. Two of these complexes were derived from a symmetrical benzaldehyde phthalocyanine complex via the condensation of the benzaldehyde substituents with amine reagents. The electrocatalysts proved to be highly stable towards the detection of catechol. The oxidation peaks obtained using cyclic voltammetry range from 0.20 to 0.38 V. Detection limits were obtained via chronoamperometry and are as low as 0.16 µM with fairly high sensitives being obtained. Overall all four copper complexes exhibited excellent electrocatalytic activity towards the electrooxidation of catechol.
- Full Text:
- Date Issued: 2021
Symmetry effect of cobalt phthalocyanines on the aluminium corrosion inhibition in hydrochloric acid
- Nnaji, Nnaemeka, Sen, Pinar, Nyokong, Tebello
- Authors: Nnaji, Nnaemeka , Sen, Pinar , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231323 , vital:49877 , xlink:href="https://doi.org/10.1016/j.matlet.2021.130892"
- Description: The aluminium corrosion retardation potentials of phthalocyanine-based dyes, cobalt (II) 2,9,16-tris(4-(tert-butyl)phenoxy)-23-(pyridin-4-yloxy)phthalocyanine (D1) and cobalt (II) 2,9,16,24-tetrakis(4-(tert-butyl)phenoxy)phthalocyanine (D2) in 1 M hydrochloric acid were evaluated. Results from potentiodynamic polarization measurements show that inhibition efficiency increased with inhibitor concentration at 28 °C with values of 91.9 % and 87.0 % values respectively for D1 and D2 at 10 μM.
- Full Text:
- Date Issued: 2022
Symmetry effect of cobalt phthalocyanines on the aluminium corrosion inhibition in hydrochloric acid
- Authors: Nnaji, Nnaemeka , Sen, Pinar , Nyokong, Tebello
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231323 , vital:49877 , xlink:href="https://doi.org/10.1016/j.matlet.2021.130892"
- Description: The aluminium corrosion retardation potentials of phthalocyanine-based dyes, cobalt (II) 2,9,16-tris(4-(tert-butyl)phenoxy)-23-(pyridin-4-yloxy)phthalocyanine (D1) and cobalt (II) 2,9,16,24-tetrakis(4-(tert-butyl)phenoxy)phthalocyanine (D2) in 1 M hydrochloric acid were evaluated. Results from potentiodynamic polarization measurements show that inhibition efficiency increased with inhibitor concentration at 28 °C with values of 91.9 % and 87.0 % values respectively for D1 and D2 at 10 μM.
- Full Text:
- Date Issued: 2022
Aluminum corrosion retardation properties of acetamidophenoxy phthalocyanines: Effect of central metal
- Nnaji, Nnaemeka, Sen, Pinar, Nyokong, Tebello
- Authors: Nnaji, Nnaemeka , Sen, Pinar , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185433 , vital:44386 , xlink:href="https://doi.org/10.1016/j.molstruc.2021.130806"
- Description: Corrosion inhibition performances and adsorption behaviour at the aluminum-HCl solution interface were investigated for metal free (2), ClGa (3) and Co (4) tetrakis (4-acetamidophenoxy) phthalocyanine. Electrochemical techniques were used in the study and complemented with Fourier transform infrared, scanning electron microscopy and X-ray diffraction measurements. Potentiodynamic polarization technique gave inhibition efficiency values as 93.3% (2), 69.7% (3) and 87.7% (4) at 28°C at highest inhibitor concentration (10 µM) in the following order 2 > 4 > 3. These compounds exhibited good corrosion inhibition performance as mixed-type corrosion inhibitors. All applied techniques gave results which corroborated.
- Full Text:
- Date Issued: 2021
- Authors: Nnaji, Nnaemeka , Sen, Pinar , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/185433 , vital:44386 , xlink:href="https://doi.org/10.1016/j.molstruc.2021.130806"
- Description: Corrosion inhibition performances and adsorption behaviour at the aluminum-HCl solution interface were investigated for metal free (2), ClGa (3) and Co (4) tetrakis (4-acetamidophenoxy) phthalocyanine. Electrochemical techniques were used in the study and complemented with Fourier transform infrared, scanning electron microscopy and X-ray diffraction measurements. Potentiodynamic polarization technique gave inhibition efficiency values as 93.3% (2), 69.7% (3) and 87.7% (4) at 28°C at highest inhibitor concentration (10 µM) in the following order 2 > 4 > 3. These compounds exhibited good corrosion inhibition performance as mixed-type corrosion inhibitors. All applied techniques gave results which corroborated.
- Full Text:
- Date Issued: 2021
Acetophenone substituted phthalocyanines and their graphene quantum dots conjugates as photosensitizers for photodynamic antimicrobial chemotherapy against Staphylococcus aureus
- Openda, Yolande I, Sen, Pinar, Managa, Muthumuni, Nyokong, Tebello
- Authors: Openda, Yolande I , Sen, Pinar , Managa, Muthumuni , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186507 , vital:44506 , xlink:href="https://doi.org/10.1016/j.pdpdt.2019.101607"
- Description: This work reports on the synthesis and characterization of novel acetophenone substituted phthalocyanines along with the self-assembled nanoconjugates formed via π-π stacking interaction between the synthesized unmetalated (2), zinc (3) and indium (4) phthalocyanines and graphene quantum dots (GQDs) to form 2@GQDs, 3@GQDs and 4@GQDs. The complexes and conjugates exhibited high singlet oxygen ranging from 0.20 to 0.79 in DMSO for Pcs and nanoconjugates where in all cases, the indium complexes showed the highest singlet oxygen quantum yields. The photodynamic antimicrobial chemotherapy activity of both phthalocyanines and nanoconjugates were tested against Staphylococcus aureus. 4@GQDs was found to be highly effective causing a 9.68 log reduction of the bacteria at 10 μM (based on Pc) when compared to 3.77 log reduction of 3@GQDs.
- Full Text:
- Date Issued: 2020
- Authors: Openda, Yolande I , Sen, Pinar , Managa, Muthumuni , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186507 , vital:44506 , xlink:href="https://doi.org/10.1016/j.pdpdt.2019.101607"
- Description: This work reports on the synthesis and characterization of novel acetophenone substituted phthalocyanines along with the self-assembled nanoconjugates formed via π-π stacking interaction between the synthesized unmetalated (2), zinc (3) and indium (4) phthalocyanines and graphene quantum dots (GQDs) to form 2@GQDs, 3@GQDs and 4@GQDs. The complexes and conjugates exhibited high singlet oxygen ranging from 0.20 to 0.79 in DMSO for Pcs and nanoconjugates where in all cases, the indium complexes showed the highest singlet oxygen quantum yields. The photodynamic antimicrobial chemotherapy activity of both phthalocyanines and nanoconjugates were tested against Staphylococcus aureus. 4@GQDs was found to be highly effective causing a 9.68 log reduction of the bacteria at 10 μM (based on Pc) when compared to 3.77 log reduction of 3@GQDs.
- Full Text:
- Date Issued: 2020
Synthesis and photophysicochemical properties of novel axially di-substituted silicon (IV) phthalocyanines and their photodynamic antimicrobial chemotherapy (PACT) activity against Staphylococcus aureus
- Sen, Pinar, Sindelo, Azole, Mafukidze, Donovan M, Nyokong, Tebello
- Authors: Sen, Pinar , Sindelo, Azole , Mafukidze, Donovan M , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186757 , vital:44531 , xlink:href="https://doi.org/10.1016/j.synthmet.2019.116203"
- Description: In this study, novel silicon (IV) phthalocyanine axially di-substituted with benzimidazole moieties (3) and its quaternized derivative (4) have been synthesized and fully characterized. The photophysical and photochemical properties of both phthalocyanines such as absorption, fluorescence and, singlet oxygen quantum yields, triplet state quantum yields and exited state lifetimes were investigated in solutions. These new silicon phthalocyanines exhibited low fluorescence but produced high singlet oxygen yields in both DMSO (compound 3 and 4) and aqueous media (compound 4). The quaternization of Si(IV)Pc (3) improved the triplet state quantum yield (ΦT) 0.61 to 0.83, consequently singlet oxygen generation (ΦΔ) increased to 0.69 from 0.42. Photodynamic antimicrobial chemotherapy activities (PACT) of Si(IV)Pc photosensitizers were determined towards Staphylococcus aureus. The higher efficiency was obtained with cationic derivative (4) giving reduction percentage value of 99.75%.
- Full Text:
- Date Issued: 2019
- Authors: Sen, Pinar , Sindelo, Azole , Mafukidze, Donovan M , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186757 , vital:44531 , xlink:href="https://doi.org/10.1016/j.synthmet.2019.116203"
- Description: In this study, novel silicon (IV) phthalocyanine axially di-substituted with benzimidazole moieties (3) and its quaternized derivative (4) have been synthesized and fully characterized. The photophysical and photochemical properties of both phthalocyanines such as absorption, fluorescence and, singlet oxygen quantum yields, triplet state quantum yields and exited state lifetimes were investigated in solutions. These new silicon phthalocyanines exhibited low fluorescence but produced high singlet oxygen yields in both DMSO (compound 3 and 4) and aqueous media (compound 4). The quaternization of Si(IV)Pc (3) improved the triplet state quantum yield (ΦT) 0.61 to 0.83, consequently singlet oxygen generation (ΦΔ) increased to 0.69 from 0.42. Photodynamic antimicrobial chemotherapy activities (PACT) of Si(IV)Pc photosensitizers were determined towards Staphylococcus aureus. The higher efficiency was obtained with cationic derivative (4) giving reduction percentage value of 99.75%.
- Full Text:
- Date Issued: 2019
New type of metal-free and Zinc (II), In (III), Ga (III) phthalocyanines carrying biologically active substituents: Synthesis and photophysicochemical properties and photodynamic therapy activity
- Sen, Pinar, Managa, Muthumuni, Nyokong, Tebello
- Authors: Sen, Pinar , Managa, Muthumuni , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186971 , vital:44552 , xlink:href="https://doi.org/10.1016/j.ica.2019.03.010"
- Description: This study reports on novel phthalocyanines having benzimidazole units which are known to have biological properties. 4-(4-(5-chloro-1H-benzo[d]imidazol-2-yl) substituted metal-free, Zn(II), In(III) and Ga(III) phthalocyanines were synthesized, these newly synthesized molecules that were substituted by oxygen bridges were fully characterized. For the purpose of determining their potency for photodynamic therapy, the photophysicochemical properties were investigated in DMSO. The H2Pc (4) showed higher fluorescence quantum yield and fluorescence lifetime as compared to metallated phthalocyanines derivatives. However, the highest singlet oxygen (ΦΔ) and triplet state quantum yields (ΦT) values were obtained with the In(III)Pc (5).
- Full Text:
- Date Issued: 2019
- Authors: Sen, Pinar , Managa, Muthumuni , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186971 , vital:44552 , xlink:href="https://doi.org/10.1016/j.ica.2019.03.010"
- Description: This study reports on novel phthalocyanines having benzimidazole units which are known to have biological properties. 4-(4-(5-chloro-1H-benzo[d]imidazol-2-yl) substituted metal-free, Zn(II), In(III) and Ga(III) phthalocyanines were synthesized, these newly synthesized molecules that were substituted by oxygen bridges were fully characterized. For the purpose of determining their potency for photodynamic therapy, the photophysicochemical properties were investigated in DMSO. The H2Pc (4) showed higher fluorescence quantum yield and fluorescence lifetime as compared to metallated phthalocyanines derivatives. However, the highest singlet oxygen (ΦΔ) and triplet state quantum yields (ΦT) values were obtained with the In(III)Pc (5).
- Full Text:
- Date Issued: 2019
A novel axially palladium (II)-Schiff base complex substituted silicon (IV) phthalocyanine
- Sen, Pinar, Nyokong, Tebello
- Authors: Sen, Pinar , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186813 , vital:44536 , xlink:href="https://doi.org/10.1016/j.poly.2019.114135"
- Description: In this study, a novel silicon(IV) phthalocyanine is reported for the first time as a phthalocyanine derivative bearing axially a palladium(II)-Schiff base complex. The photophysical and photochemical properties of the new Si(IV)Pc, such as absorption, fluorescence, singlet oxygen quantum yields, triplet state quantum yields and exited state lifetimes were measured in DMSO. The new silicon phthalocyanine displayed very low fluorescence, showing efficient intersystem crossing resulting in high triplet and high singlet oxygen quantum yields in DMSO. When compared with the unsubstituted SiPcCl2, the singlet oxygen quantum yield value (UD = 0.47) in relation to the triplet quantum yield (UT = 0.82), which is an important determinant for PDT applications, increased. The photodynamic antimicrobial chemotherapy activity (PACT) of new Si(IV)Pc towards Staphylococcus aureus was determined in comparison to the unsubstituted SiPcCl2. The results of the photodynamic antimicrobial effect study demonstrated that the Pd(II) complex substituted SiPc (5) possesses excellent photodynamic activity with a reduction percentage value of 99.94% and a log red value of 3.26.
- Full Text:
- Date Issued: 2019
- Authors: Sen, Pinar , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186813 , vital:44536 , xlink:href="https://doi.org/10.1016/j.poly.2019.114135"
- Description: In this study, a novel silicon(IV) phthalocyanine is reported for the first time as a phthalocyanine derivative bearing axially a palladium(II)-Schiff base complex. The photophysical and photochemical properties of the new Si(IV)Pc, such as absorption, fluorescence, singlet oxygen quantum yields, triplet state quantum yields and exited state lifetimes were measured in DMSO. The new silicon phthalocyanine displayed very low fluorescence, showing efficient intersystem crossing resulting in high triplet and high singlet oxygen quantum yields in DMSO. When compared with the unsubstituted SiPcCl2, the singlet oxygen quantum yield value (UD = 0.47) in relation to the triplet quantum yield (UT = 0.82), which is an important determinant for PDT applications, increased. The photodynamic antimicrobial chemotherapy activity (PACT) of new Si(IV)Pc towards Staphylococcus aureus was determined in comparison to the unsubstituted SiPcCl2. The results of the photodynamic antimicrobial effect study demonstrated that the Pd(II) complex substituted SiPc (5) possesses excellent photodynamic activity with a reduction percentage value of 99.94% and a log red value of 3.26.
- Full Text:
- Date Issued: 2019
Synthesis of novel Schiff base cobalt (II) and iron (iii) complexes as cathode catalysts for microbial fuel cell applications
- Sen, Pinar, Akagunduz, Dilan, Aghdam, Araz S, Cebeci, Fevzi C, Nyokong, Tebello, Catal, Tunc
- Authors: Sen, Pinar , Akagunduz, Dilan , Aghdam, Araz S , Cebeci, Fevzi C , Nyokong, Tebello , Catal, Tunc
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/190861 , vital:45035 , xlink:href="https://doi.org/10.1007/s10904-019-01286-x"
- Description: In this study, the synthesis and characterization of a new Schiff base and its cobalt(II) and iron(III) complexes were performed fully characterized by common spectroscopic techniques such as 1H-NMR, 13C-NMR, FT-IR, UV–Vis and MS and elemental analysis. The cathodes prepared with only activated carbon, Co-Schiff base complex, and Fe-Schiff base complex mixed with activated carbon as the carrier were examined in single chamber air cathode microbial fuel cells (MFCs). The spectroscopic results confirm the structure of novel Schiff base and its complexes with cobalt (II) and Fe(III). MFC results showed that Fe-Schiff base complex generated higher voltage generation using glucose as the carbon source. Cyclic voltammetry results showed the conductivity and catalytic features of the cathodes developed in this study. Scanning electron microscopic results showed the distribution the complexes on the cathode surface. In conclusion, a novel Schiff base and its complexes with cobalt (II) and iron (III) can be employed into MFC technology to be used in green electricity production, and might help decreasing the operating costs of wastewater treatment plants.
- Full Text:
- Date Issued: 2020
- Authors: Sen, Pinar , Akagunduz, Dilan , Aghdam, Araz S , Cebeci, Fevzi C , Nyokong, Tebello , Catal, Tunc
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/190861 , vital:45035 , xlink:href="https://doi.org/10.1007/s10904-019-01286-x"
- Description: In this study, the synthesis and characterization of a new Schiff base and its cobalt(II) and iron(III) complexes were performed fully characterized by common spectroscopic techniques such as 1H-NMR, 13C-NMR, FT-IR, UV–Vis and MS and elemental analysis. The cathodes prepared with only activated carbon, Co-Schiff base complex, and Fe-Schiff base complex mixed with activated carbon as the carrier were examined in single chamber air cathode microbial fuel cells (MFCs). The spectroscopic results confirm the structure of novel Schiff base and its complexes with cobalt (II) and Fe(III). MFC results showed that Fe-Schiff base complex generated higher voltage generation using glucose as the carbon source. Cyclic voltammetry results showed the conductivity and catalytic features of the cathodes developed in this study. Scanning electron microscopic results showed the distribution the complexes on the cathode surface. In conclusion, a novel Schiff base and its complexes with cobalt (II) and iron (III) can be employed into MFC technology to be used in green electricity production, and might help decreasing the operating costs of wastewater treatment plants.
- Full Text:
- Date Issued: 2020
Synthesis of novel Schiff base cobalt (II) and iron (iii) complexes as cathode catalysts for microbial fuel cell applications
- Sen, Pinar, Akagunduz, Dilan, Aghdam, Araz Sheibani, Cebeci, Fevzi C, Nyokong, Tebello
- Authors: Sen, Pinar , Akagunduz, Dilan , Aghdam, Araz Sheibani , Cebeci, Fevzi C , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187015 , vital:44556 , xlink:href="https://doi.org/10.1007/s10904-019-01286-x"
- Description: In this study, the synthesis and characterization of a new Schiff base and its cobalt(II) and iron(III) complexes were performed fully characterized by common spectroscopic techniques such as 1H-NMR, 13C-NMR, FT-IR, UV–Vis and MS and elemental analysis. The cathodes prepared with only activated carbon, Co-Schiff base complex, and Fe-Schiff base complex mixed with activated carbon as the carrier were examined in single chamber air cathode microbial fuel cells (MFCs). The spectroscopic results confirm the structure of novel Schiff base and its complexes with cobalt (II) and Fe(III). MFC results showed that Fe-Schiff base complex generated higher voltage generation using glucose as the carbon source. Cyclic voltammetry results showed the conductivity and catalytic features of the cathodes developed in this study. Scanning electron microscopic results showed the distribution the complexes on the cathode surface. In conclusion, a novel Schiff base and its complexes with cobalt (II) and iron (III) can be employed into MFC technology to be used in green electricity production, and might help decreasing the operating costs of wastewater treatment plants.
- Full Text:
- Date Issued: 2020
- Authors: Sen, Pinar , Akagunduz, Dilan , Aghdam, Araz Sheibani , Cebeci, Fevzi C , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187015 , vital:44556 , xlink:href="https://doi.org/10.1007/s10904-019-01286-x"
- Description: In this study, the synthesis and characterization of a new Schiff base and its cobalt(II) and iron(III) complexes were performed fully characterized by common spectroscopic techniques such as 1H-NMR, 13C-NMR, FT-IR, UV–Vis and MS and elemental analysis. The cathodes prepared with only activated carbon, Co-Schiff base complex, and Fe-Schiff base complex mixed with activated carbon as the carrier were examined in single chamber air cathode microbial fuel cells (MFCs). The spectroscopic results confirm the structure of novel Schiff base and its complexes with cobalt (II) and Fe(III). MFC results showed that Fe-Schiff base complex generated higher voltage generation using glucose as the carbon source. Cyclic voltammetry results showed the conductivity and catalytic features of the cathodes developed in this study. Scanning electron microscopic results showed the distribution the complexes on the cathode surface. In conclusion, a novel Schiff base and its complexes with cobalt (II) and iron (III) can be employed into MFC technology to be used in green electricity production, and might help decreasing the operating costs of wastewater treatment plants.
- Full Text:
- Date Issued: 2020