List of Titles

Intra- and interspecific brood recognition in pure and mixed-species honeybee colonies, Apis cerana and A. mellifera

- Tan, K, Yang, M-X, Radloff, Sarah E, Yu, Y, Pirk, C W W, Hepburn, H Randall

Authors: Tan, K , Yang, M-X , Radloff, Sarah E , Yu, Y , Pirk, C W W , Hepburn, H Randall
Date: 2009
Subjects: Apis mellifera Apis cerana
Language: English
Type: text , Article
Identifier: vital:6837 , http://hdl.handle.net/10962/d1010962 , http://dx.doi.org/10.1051/apido/2009003
Description: We studied the effects of mixed honeybee colonies of Apis mellifera and Apis cerana on the intraspecific and interspecific recognition of female brood stages in the honeybees A. cerana and A. mellifera by transferring brood combs between queenright colonies. In the intraspecific tests, significantly more larvae were removed in A. cerana than in A. mellifera, whilst significantly fewer eggs and pupae were removed in A. cerana than in A. mellifera. In the interspecific tests, A. cerana colonies removed significantly more larvae and pupae of A. mellifera than the same brood stages of A. cerana were removed by A. mellifera. We show there are highly significant differences in both intraspecific and interspecific brood recognition between A. cerana and A. mellifera and that brood recognition operates with decreasing intensity with increasing developmental age within species. This suggests that worker policing in egg removal is a first line of defense against heterospecific social parasites.
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Date Issued: 2009

Investigating how the attributes of live theatre productions influence consumption choices using conjoint analysis : the example of the National Arts Festival, South Africa

- Willis, K G, Snowball, Jeanette D

Authors: Willis, K G , Snowball, Jeanette D
Date: 2009
Language: English
Type: Article
Identifier: vital:6075 , http://hdl.handle.net/10962/d1003825 , http://dx.doi.org/10.1007/s10824-009-9097-z
Description: While there is a fair amount of work on determinants of demand for the live performing arts, results have often been contradictory with little explanatory power. This may be because of the difficulty in describing the attributes of a performance, particularly in terms of its quality, and the heterogeneity of consumer preferences. This article uses conjoint analysis, also called choice experiments, to investigate the impact of the attributes of live theatre performances on demand, using data collected from 483 randomly chosen attenders at live theatre performances at the 2008 South African National Arts Festival. Attributes include the type of cast (professional, semi-professional or amateur), reputation of the producer/director, the context or setting, production type and ticket price of the show. Results largely support the a priori expectations based on the results of other demand studies. For example, it is found that the age of consumers affects the type of show chosen, that utility and willingness to pay increase for shows with professional and semi-professional casts and that 93% of the potential audience prefer shows with a South African context. It is concluded that the method could prove useful to both event organisers and policy makers, especially where the goal is to broaden access to the arts.
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Date Issued: 2009

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Is HIV/AIDS jeopardizing biodiversity?

- McGarry, Dylan K, Shackleton, Charlie M

Authors: McGarry, Dylan K , Shackleton, Charlie M
Date: 2009
Language: English
Type: Article
Identifier: vital:6642 , http://hdl.handle.net/10962/d1006871
Description: The scourge of HIV/AIDS (human immunodeficiency virus/acquired immune deficiency syndrome) is most prevalent in southern Africa. South Africa has the highest number of people in the world living with HIV/AIDS and a prevalence rate of over 30 % for females presenting at antenatal clinics. There are now almost five million orphans within southern Africa, as a result of AIDS deaths of one or more or their parents. AIDS-related mortality and morbidity of care-givers may lead to increased reliance on wild sources of animal protein by surviving children. This increase in hunting pressure has unknown, but potentially important impacts on local animal populations.
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Date Issued: 2009

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Jimmy Riadore: organ-builder, bell-ringer and hanger of the bells at St George's Cathedral, Cape Town

- Lewis, Colin A

Authors: Lewis, Colin A
Date: 2009
Language: English
Type: Article
Identifier: vital:6190 , http://hdl.handle.net/10962/d1012396
Description: Born in Lewes, Sussex, Jimmy Riadore came to South Africa in 1958. Organs, bells and clocks have been the focus of his life, and he has tuned, built, repaired and restored them all over southern Africa. Recently he has extended his careful ministrations to St Helena. , Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
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Date Issued: 2009

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Luminescence lifetime components in quartz: influence of irradiation and annealing

- Chithambo, Makaiko L, Ogundare, F O

Authors: Chithambo, Makaiko L , Ogundare, F O
Date: 2009
Language: English
Type: Article
Identifier: vital:6811 , http://hdl.handle.net/10962/d1004304
Description: Pulsed optically stimulated luminescence measured from quartz under certain combinations of annealing and measurement temperature can be resolved into multiple lifetime components. We have studied the influence on these lifetime components of annealing temperature up to 900 °C, beta irradiation dose as high as 1700 Gy, and temperature of stimulation up to 200 °C. Although the time-resolved spectra from which the lifetimes are determined may be measured without heating between irradiation and measurement, a necessary protocol in steady-state optical stimulation applications, studies reported in this paper have been augmented with investigations on the effect of temperature and duration of preheating on the principal and secondary lifetimes. Luminescence spectra for measurements up to 200 Gy consist of a single lifetime but two components occur thereafter, both are independent of radiation dose. The principal lifetime of 35 μs is not affected by temperature of anneal whereas the secondary lifetime increases from 9 to 18 μs when the annealing temperature is changed from 600 to 900 °C. The dependence of both the principal and secondary luminescence lifetimes on measurement temperature can be explained by thermal quenching of the associated luminescence. However, the influence of irradiation, preheating, and annealing on the lifetimes can be explained with reference to an energy band scheme in which the primary mechanism in the processes leading up to luminescence emission is the change in concentration of holes at various luminescence centres caused by annealing.
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Date Issued: 2009

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Municipal commonage policy and livestock owners : findings from the Eastern Cape, South Africa

- Davenport, Nicholas A, Gambiza, James

Authors: Davenport, Nicholas A , Gambiza, James
Date: 2009
Language: English
Type: Article
Identifier: vital:6628 , http://hdl.handle.net/10962/d1006820
Description: The new African National Congress government announced after 1994 that municipal commonage would be a pillar of their land reform programme. The Department of Land Affairs spearheaded this by acquiring new land to complement the existing ‘old’ commonages. The aim of old commonage was to supplement the income of poor urban residents through the subsistence user system whereas new commonage was intended as a ‘stepping stone’ for emergent farmers. We investigated the differences between old and new commonage farmers as well as how they perceived the Makana local municipality's capacity to manage the commonage. The results showed that local institutions were weak. Only 46% of the old commonage farmers were members of a local livestock association whereas 74% of the new commonage farmers were members. Most old commonage farmers (59%) were dissatisfied with local government's management of the commonage. In contrast, only 37% of the new commonage farmers were dissatisfied with the management of the commonage. There were no differences between old and new commonage farmers in terms of livestock owners’ characteristics and mean annual net direct-use value of livestock. There were also no differences in the age of the two types of commonage farmers. Furthermore, there was no association between the type of commonage and level of education. The mean annual net direct-use value of livestock on old commonage was R6308 compared with R9707 on new commonage. Although the income from livestock for new commonage farmers varied slightly from that of old commonage farmers, the annual productive output per farmer on old commonage was R473 ha−1, three times higher than that of new commonage farmers which was R134 ha−1. We suggest that new land policy legislation is needed in which poverty as well as the legal arrangements between all stakeholders is clearly defined. Furthermore, national departments need to be more involved with local municipalities to increase local management capacity.
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Date Issued: 2009

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New soluble methylendioxy-phenoxy-substituted zinc phthalocyanine derivatives : synthesis, photophysical and photochemical studies

- Erdoğmuş, Ali, Nyokong, Tebello

Authors: Erdoğmuş, Ali , Nyokong, Tebello
Date: 2009
Language: English
Type: Article
Identifier: vital:6572 , http://hdl.handle.net/10962/d1004135
Description: The syntheses of new three phthalonitriles (1, 2 and 3), together with photophysical and photochemical properties of the resulting peripherally and non-peripherally tetrakis- and octakis 3,4-(methylendioxy)-phenoxy-substituted zinc phthalocyanines (4, 5 and 6) are described for the first time. Complexes 4, 5 and 6 have been synthesized and characterized by elemental analysis, IR, 1H NMR spectroscopy, electronic spectroscopy and mass spectra. Complexes 4, 5 and 6 have good solubility in organic solvents such as CHCl3, DCM, DMSO, DMF, THF and toluene and are mainly not aggregated (except for complex 6 in DMSO) within a wide concentration range. General trends are described for singlet oxygen, photodegradation, fluorescence quantum yields, triplet quantum yields and triplet life times of these complexes in DMSO and toluene. Complex 4 has higher singlet oxygen quantum yields, fluorescence quantum yields, triplet quantum yields and triplet life times than complexes 5 and 6. The effect of the solvents on the photophysical and photochemical parameters of the zinc(II) phthalocyanines (4, 5 and 6) are also reported.
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Date Issued: 2009

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Obesity: a preliminary report of an introductory service-learning course on the role of pharmacy students in health promotion

- Srinivas, Sunitha C, Wrench, Wendy W, Karekazi, Catherine W, Radloff, Sarah E, Daya, Santylal

Authors: Srinivas, Sunitha C , Wrench, Wendy W , Karekazi, Catherine W , Radloff, Sarah E , Daya, Santylal
Date: 2009
Language: English
Type: text , Article
Identifier: vital:6454 , http://hdl.handle.net/10962/d1006833
Description: Lifestyle diseases such as obesity have been neglected in developing countries partly due to a more urgent focus on infectious diseases in these countries. The incidence of obesity is on the increase in developing countries, with a marked rise in childhood obesity. A health promotioning service-learning principles required final year pharmacy students to prepare a pilot-tested computer-based quiz, using a pre- and post-intervention test design, along with other learning material, for participants at the 2007 Sasol National Festival of Science and Technology (SciFest). Interactive models, posters and information leaflets were used in explaining the prevention and control of obesity to learners. The results showed that the pre-existing knowledge of the participants was good. There was a further improvement after the educational intervention. Activities such as this are important in heightening awareness of obesity in learners as it is likely to reduce the incidence of obesity later in life. Furthermore, the activity also served to increase awareness of the role of pharmacists in the prevention of lifestyle diseases such as obesity.
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Date Issued: 2009

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Plants for health, life and spirit in Africa : implications for biodiversity and cultural diversity conservation

- Cocks, Michelle L, Dold, Anthony P

Authors: Cocks, Michelle L , Dold, Anthony P
Date: 2009
Language: English
Type: Article
Identifier: vital:6617 , http://hdl.handle.net/10962/d1016225
Description: [From Introduction] Natural resources are often only perceived as contributing to rural livelihoods through food production and household welfare. There is a growing wealth of information capturing the direct-use values of the environment and consequent recognition of natural resources as being “the poor man's overcoat”. These approaches, however, have failed to fully account for the various ways in which different groups of people make use of, and find value in biodiversity. New developments within the field of anthropology have begun to explore the relationship between biodiversity and human diversity. This view has largely come about because many of the areas of highest biological diversity are inhabited by indigenous and traditional people, providing what the Declaration of Belem (1988) calls an 'inextricable link' between biological and cultural diversity (Posey 1999). The term bio-cultural diversity was introduced by Posey in 1999 to describe the concept denoting this link. , Funding was received from the South Africa-Netherlands Programme on Alternatives in Development (SANPAD) and the International Foundation of Science (IFS)
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Date Issued: 2009

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Pollinators, “mustard oil” volatiles, and fruit production in flowers of the dioecious tree Drypetes natalensis (Putranjivaceae)

- Johnson, Steven D, Griffiths, Megan E, Peter, Craig I, Lawes, Michael J

Authors: Johnson, Steven D , Griffiths, Megan E , Peter, Craig I , Lawes, Michael J
Date: 2009
Language: English
Type: Article
Identifier: vital:6519 , http://hdl.handle.net/10962/d1005948
Description: The Putranjivaceae is an enigmatic family, notable for being the only lineage outside the Capparales to possess the glucosinolate biochemical pathway, which forms the basis of an induced chemical defense system against herbivores (the “ mustard oil bomb ” ). We investigated the pollination biology and fl oral scent chemistry of Drypetes natalensis (Putranjivaceae), a dioecious subcanopy tree with fl owers borne on the stem (caulifl ory). Flowering male trees were more abundant than female ones and produced about 10-fold more fl owers. Flowers of both sexes produce copious amounts of nectar on disc-like nectaries accessible to short-tongued insects. The main fl ower visitors observed were cetoniid beetles, bees, and vespid wasps. Pollen load analysis indicated that these insects exhibit a high degree of fi delity to D. natalensis fl owers. Insects effectively transfer pollen from male to female plants resulting in about 31% of female fl owers developing fruits with viable seeds. Cetoniid beetles showed signifi cant orientation toward the scent of D. natalensis fl owers in a Y-maze olfactometer. The scents of male and female fl owers are similar in chemical composition and dominated by fatty acid derivatives and isothiocyanates from the glucosinolate pathway. The apparent constitutive emission of isothiocyanates raises interesting new questions about their functional role in flowers.
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Date Issued: 2009

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Possible trace fossils of putative termite origin in the Lower Jurassic (Karoo Supergroup) of South Africa and Lesotho

- Bordy, Emese M, Bumby, A J, Catuneanu, O, Eriksson, P G

Authors: Bordy, Emese M , Bumby, A J , Catuneanu, O , Eriksson, P G
Date: 2009
Language: English
Type: Article
Identifier: vital:6732 , http://hdl.handle.net/10962/d1007541
Description: Complex structures in the sandstones of the Lower Jurassic aeolian Clarens Formation (Karoo Supergroup) are found at numerous localities throughout southern Africa, and can be assigned to five distinct architectural groups: (1) up to 3.3-m high, free-standing, slab-shaped forms of bioturbated sandstones with elliptical bases, orientated buttresses and an interconnecting large burrow system; (2) up to 1.2-m high, free-standing, irregular forms of bioturbated sandstones with 2-cm to 4-cm thick, massive walls, empty chambers and vertical shafts; (3) about 0.15-m to 0.25-m high, mainly bulbous, multiple forms with thin walls (<2 cm), hollow chambers with internal pillars and bridges; (4) about 0.15-m to 0.2-m (maximum 1-m) high, free-standing forms of aggregated solitary spheres associated with massive horizontal, orientated capsules or tubes, and meniscate tubes; and (5) about 5 cmin diameter, ovoid forms with weak internal shelving in a close-fitting cavity. Based on size, wall thickness, orientation and the presence of internal chambers, these complex structures are tentatively interpreted as ichnofossils of an Early Jurassic social organism; the different architectures are reflective of the different behaviours of more than one species, the history of structural change in architectural forms (ontogenetic series) or an architectural adaptation to local palaeoclimatic variability. While exact modern equivalents are unknown, some of these ichnofossils are comparable to nests (or parts of nests) constructed by extant termites, and thus these Jurassic structures are very tentatively interpreted here as having been made by a soil-dwelling social organism, probably of termite origin. This southern African discovery, along with reported Triassic and Jurassic termite ichnofossils from North America, supports previous hypotheses that sociality in insects, particularity in termites, likely evolved prior to the Pangea breakup in the Early Mesozoic.
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Date Issued: 2009

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Predicting geographic distribution of seven blowfly species (Diptera: Calliphoridae) in South Africa

- Richards, Cameron S, Williams, Kirstin A, Villet, Martin H

Authors: Richards, Cameron S , Williams, Kirstin A , Villet, Martin H
Date: 2009
Language: English
Type: text , Article
Identifier: vital:6854 , http://hdl.handle.net/10962/d1011135
Description: The predicted geographic distributions of seven forensically important blowfly species are modelled using the computer program Maxent, based on selected climatic variables for South Africa, a country with large climatic and environmental gradients. It is shown that although temperature was hypothesized to most influence the distributions of these ectotherms, moisture, and particularly humidity, was in fact usually paramount. Chrysomya albiceps (Wiedemann) and C. marginalis (Robineau-Desvoidy) had the most widespread geographic and climatic distribution, while the forest-associated C. inclinata(Walker) was the least widespread. Chrysomya putoria (Wiedemann) and C. megacephala (Fabricius) had very similar predicted distributions that were restricted mainly to Limpopo, Mpumalanga, KwaZulu-Natal and the coast of the Eastern Cape. Chrysomya chloropyga (Wiedemann) and Calliphora croceipalpis (Jaennicke) were the only species predicted to occur at high altitudes. Blowfly distributions restricted to part of the map area were predicted better than those that were more widespread in the region, presumably because species with extremely widespread distributions in a study area occupy nearly the whole range of variation of most predictor variables, leaving little variation with which themaximumentropy modelling method can discriminate between presence and absence of the organism.
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Date Issued: 2009

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Promoting indigenous vegetables in urban agriculture & livelihoods : policy lessons from Sub-Saharan Africa

- Shackleton, Charlie M, Pasquini, Margaret W, Ambrose-Oji, Bianca, Drescher, Axel W

Authors: Shackleton, Charlie M , Pasquini, Margaret W , Ambrose-Oji, Bianca , Drescher, Axel W
Date: 2009
Language: English
Type: Article
Identifier: vital:6619 , http://hdl.handle.net/10962/d1016227
Description: [From Introduction] Globally, the growth of urbanised areas continues at an exponential rate, and most spectacularly in the developing world. The global urban population will increase from 2.9 billion in 2000 to 5.0 billion by 2030. The mean rate of urban growth in non-OECD countries between 2000 and 2005 was just under 3% per annum, compared to 0.5 % for rural regions of the same countries (UN-Habitat 2006). Although the proportion of Africans currently living in urban areas is the lowest in the world (+ 40%), because of this low base it is not unsurprising that the rates of urbanisation are among the highest at approximately 4.3% per annum. Projections vary, but sometime in the mid- 2020s over 50% of Africa's population will be living in urban areas, as compared to just 15% in 1950 and 34% in 1994. As urbanisation takes place another important trend is revealed, namely the locus of poverty in Africa is slowly shifting from rural to urban areas. For example, it is estimated that more than 56% of the world's absolute or chronic poor will be concentrated in urban areas (WRI 1996). Since as much as 60-80% of the income of the urban poor is spent on the purchase of food (Maxwell et al. 2000), the issue of food supply, both its quantity and quality, is increasingly a central issue in poverty reduction debates and strategies. In rural areas, a common strategy to alleviate poverty is to call for measures to boost small-holder food production. Surprisingly, this is less common in urban poverty alleviation programmes, despite the widespread promise of urban and household agriculture in contributing to improved food security.
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Date Issued: 2009

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Pseudopolydora species associated with mollusc shells on the south coast of South Africa, with the description of Ps. dayii, sp nov

- Simon, Carol A

Authors: Simon, Carol A
Date: 2009
Language: English
Type: text , Article
Identifier: vital:6875 , http://hdl.handle.net/10962/d1011623
Description: Two species of the genus Pseudopolydora, Ps. dayii, sp. nov. and Ps. antennata, were associated with gastropods on the south and south-east coasts of South Africa. Pseudopolydora dayii is characterized by prominent post-chaetal notopodial lobes on chaetiger 1 with very long chaetae, a prominent occipital tentacle, having hooded hooks that start on chaetiger 9, branchiae that start on chaetiger 6, stout hooks and lobes placed latero-posteriorly to the hooded hooks in posterior chaetigers. It is a surface-fouler and was found on several species of wild gastropods at four of the five sites sampled and from additional material from the south-west coast and on cultured abalone (Haliotis midae) at a farm on the south-west coast. Three individuals of Ps. antennata were found only with oysters at the easternmost site. This was the first record of this species outside of the Western Cape Province and it is possible that their association with the oysters was fortuitous.
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Date Issued: 2009

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Quantity and significance of wild meat off-take by a rural community in the Eastern Cape, South Africa

- Kaschula, Sarah A H, Shackleton, Charlie M

Authors: Kaschula, Sarah A H , Shackleton, Charlie M
Date: 2009
Language: English
Type: Article
Identifier: vital:6638 , http://hdl.handle.net/10962/d1006864
Description: When compared to tropical forest zones in west and central Africa, off-take of wild meat from savannah and grassland biomes by local rural communities has not been well assessed. This case study of wild meat collection activities within a rural community in the Mount Frere region of the Eastern Cape (South Africa) uses last-catch records derived from 50 wild meat gatherers to calculate average off-take of taxa, species and fresh mass of wild meat per collection event. When per-event off take is overlaid onto household hunting frequency data, annual off-take would be 268.6 kg km−2 yr−1 or 3 kg person−1 yr−1 presuming constant off-take over an annual period. Monetary value of off-take would be South African R 307 (US$ 39) per household annually. For some species, off-take weight per km2 shows similar values to data from tropical forest zones, but high human population densities tend to dilute off-takes to less nutritionally significant amounts at the per person scale. However, unlike many tropical zones, none of the species harvested can be considered high-priority conservation species. Even densely populated and heavily harvested communal lands appear to offer high wild meat off-takes from low conservation priority species.
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Date Issued: 2009

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Rapid method for the quantitative determination of efavirenz in human plasma

- Kanfer, Isadore, Mogatle, Seloi

Authors: Kanfer, Isadore , Mogatle, Seloi
Date: 2009
Language: English
Type: Article
Identifier: vital:6388 , http://hdl.handle.net/10962/d1006309
Description: A pharmacokinetic interaction study between efavirenz (EFV), a non-nucleoside reverse transcriptase inhibitor used in the treatment of HIV-1 infection, and an African traditional medicine, African potato in human subjects was undertaken. This necessitated the development and validation of a quantitative method for the analysis of EFV in plasma. A simple mobile phase consisting of 0.1 M formic acid, acetonitrile and methanol (43:52:5) was pumped at a low flow rate of 0.3 ml/min through a reverse phase Phenomenex® Luna C18 (2) (5 μm, 150 mm × 2.0 mm i.d.) column maintained at 40 °C. Diclofenac sodium was used as an internal standard (IS) and EFV and IS were monitored at 247 nm and 275 nm, respectively. A simple and rapid sample preparation involved the addition of mobile phase to 100 μl of plasma to precipitate plasma proteins followed by direct injection of 10 μl of supernatant onto the column. The procedures were validated according to international standards with good reproducibility and linear response (r = 0.9990). The intra- and inter-day accuracies were between 12.3 and 17.7% at the LLOQ and between −5.8 and 9.1% for the QC samples. The intra- and inter-day precision of EFV determinations were 5.1 or less and 7.2% RSD or less, respectively across the entire QC concentration range. Mean recovery based on high, medium and low quality control standards ranged between 92.7 and 94.1% with %RSD values better than 3%. Plasma samples were evaluated for short-term (ambient temperature for 6 h) and long-term (−10 ± 2 °C for 60 days) storage conditions and were found to be stable. The method described is cost-effective and has the necessary accuracy and precision for the rapid quantitative determination of EFV in human plasma.
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Date Issued: 2009

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Rapid UPLC - MS/MS method for the determination of ketoprofen in human dermal microdialysis samples

- Tettey-Amlalo, Ralph N O, Kanfer, Isadore

Authors: Tettey-Amlalo, Ralph N O , Kanfer, Isadore
Date: 2009
Language: English
Type: text , Article
Identifier: vital:6444 , http://hdl.handle.net/10962/d1006631
Description: Dermal microdialysis (DMD) is a technique capable of determining the percutaneous penetration of drugs from topical formulations intended for local and/or regional activity. Typically, the concentrations of drug collected in dialysates are very low, generally in the ng/ml or even pg/ml range. An additional challenge is the very low volume of sample collected at each collection time and which can range from 1 to 30 μl only. Hence the objective was to develop and validate a rapid, accurate, precise, reproducible and highly sensitive LC–MS/MS method for the quantitative analysis of ketoprofen (KET) in dialystes following application of a topical gel product to the skin of human subjects. UPLC–MS/MS was used and KET was separated on an Acquity™ UPLC BEH C18 column (100 mm × 2.1 mm i.d., 1.7 μm) and analysed in negative-ion (NI) electrospray ionisation (ESI) mode. The mobile phase (MP) consisted of acetonitrile:methanol:water (60:20:20, v/v/v) under isocratic conditions at a flow rate of 0.3 ml/min. Samples were extracted using ethyl acetate with ibuprofen (IBU) as internal standard (IS) and the organic solvent was then evaporated to dryness and the residue re-constituted in methanol. 5 μl samples were injected and analysis was performed at ambient temperature 22 ± 0.5 °C. KET and IBU eluted at 1.07 and 1.49 min, respectively. KET and IBU responses were optimised at the transitions 253.00 > 209.00 and 205.00 > 161.00, respectively. Calibration curves were linear over the range 0.5–500 ng/ml with correlation coefficients > 0.999. The accuracy and precision of the method were found to be between 99.97% and 104.67% (R.S.D. < 2%) and the mean recovery of KET from normal saline was 88.03 ± 0.3% (R.S.D. < 2.20%). The LLOQ and LOD values were found to be 0.5 and 0.1 ng/ml respectively whereas the ULOD was set at 500 ng/ml. The method was successfully applied to determine the bioavailability of KET following application of topical KET gel, Fastum® gel, to the skin of human volunteers.
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Date Issued: 2009

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