- Title
- NIR Absorbing AzaBODIPY Dyes for pH Sensing
- Creator
- Kubheka, Gugu, Mack, John, Nyokong, Tebello, Zhen, Shen
- Subject
- To be catalogued
- Date
- 2020
- Type
- text
- Type
- article
- Identifier
- http://hdl.handle.net/10962/186668
- Identifier
- vital:44523
- Identifier
- xlink:href="https://doi.org/10.3390/molecules25163689"
- Description
- Two near-infrared (NIR) absorbing di(thien-2-nyl)-di(dimethylanilino)azaBODIPY dyes 2a and 2b were synthesized and characterized that differ depending on whether the dimethylaniline substituents are introduced at the 3,5- or 1,7-positions of the azaBODIPY core. The main spectral bands lie at 824 and 790 nm, respectively, in CH2Cl2. The effect of substituent position on the photophysical and pH sensing properties was analyzed through a comparison of the optical properties with the results of time-dependent density functional theory (TD-DFT) calculations. Protonation of the dimethylamino nitrogen atoms eliminates the intramolecular charge transfer properties of these compounds, and this results in a marked blue-shift of the main absorption bands to 696 and 730 nm, respectively, in CH2Cl2, and a fluorescence “turn-on” effect in the NIR region. The pH dependence studies reveal that the pKa values of the non-protonated 2a and 2b molecules are ca. 6.9 (±0.05) and 7.3 (±0.05), respectively, while that of the monoprotonated species for both dyes is ca. 1.4 (±0.05) making them potentially suitable for use as colorimetric pH indicators under highly acidic conditions.
- Format
- computer, online resource, application/pdf, 1 online resource (14 pages), pdf
- Publisher
- MDPI
- Language
- English
- Relation
- Molecules, Kubheka, G., Mack, J., Nyokong, T. and Shen, Z., 2020. NIR Absorbing AzaBODIPY Dyes for pH Sensing. Molecules, 25(16), p.3689, Molecules volume 25 number 16 p. 3689 2020 1420-3049
- Rights
- Publisher
- Rights
- Use of this resource is governed by the terms and conditions of the MDPI Open Access Statement (https://www.int-res.com/journals/terms-of-use/)
- Rights
- Open Access
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Mack, John (Associate Prof)
RU DST/NRF SARChI for Medicinal Chemistry and Nanotechnology
Nyokong, Tebello (Distinguished Professor)
RU Department of Chemistry
SDG 03. Good Health and Well-Being
| Thumbnail | File | Description | Size | Format | |||
|---|---|---|---|---|---|---|---|
| View Details Download | SOURCE1 | NIR Absorbing AzaBODIPY Dyes for pH Sensing.pdf | 4 MB | Adobe Acrobat PDF | View Details Download |