PROF. KAMAU FRANCO NGUIBUTI

An Instructional Manual for teaching African Philosophy to second year students in the department of philosophy, University of Nairobi

An Instructional Manual for teaching African Philosophy to second year students in the department of philosophy, University of Nairobi

An Instructional Manual for teaching African Philosophy to second year students in the department of philosophy, University of Nairobi

An Instructional Manual for teaching African Philosophy to second year students in the department of philosophy, University of Nairobi

An isocratic liquid chromatographic method with UV detection at 215 nm, which is suitable for the analysis of azithromycin (AZT) in bulk samples, is described. AZT is separated from its synthesis intermediates and a degradation product as well as from six unknown impurities on an XTerra RP18 column at 70 degrees C using a mobile phase consisting of acetonitrile-pH 6.5 0.2M K2HPO4-water (35:10:55, v/v/v) at 1.0 mL/min. The XTerra stationary phase contains methyl groups that are incorporated in the bulk structure of the material. This allows for special selectivities. Robustness is evaluated by a full factorial design experiment. The method shows good selectivity, repeatability, linearity, and sensitivity.

An isocratic liquid chromatographic method with UV detection at 215 nm, which is suitable for the analysis of azithromycin (AZT) in bulk samples, is described. AZT is separated from its synthesis intermediates and a degradation product as well as from six unknown impurities on an XTerra RP18 column at 70 degrees C using a mobile phase consisting of acetonitrile-pH 6.5 0.2M K2HPO4-water (35:10:55, v/v/v) at 1.0 mL/min. The XTerra stationary phase contains methyl groups that are incorporated in the bulk structure of the material. This allows for special selectivities. Robustness is evaluated by a full factorial design experiment. The method shows good selectivity, repeatability, linearity, and sensitivity.

An isocratic liquid chromatographic method with UV detection at 215 nm, which is suitable for the analysis of azithromycin (AZT) in bulk samples, is described. AZT is separated from its synthesis intermediates and a degradation product as well as from six unknown impurities on an XTerra RP18 column at 70 degrees C using a mobile phase consisting of acetonitrile-pH 6.5 0.2M K2HPO4-water (35:10:55, v/v/v) at 1.0 mL/min. The XTerra stationary phase contains methyl groups that are incorporated in the bulk structure of the material. This allows for special selectivities. Robustness is evaluated by a full factorial design experiment. The method shows good selectivity, repeatability, linearity, and sensitivity.

Root and stem extracts of Girardinia diversifolia exhibited varying degrees of activity against Bacillus pumilus, Staphylococcus aureus, Escherichia coli, Aspergillus niger, Candida albicans and Saccharomyces cerevisiae. Three compounds namely ~-sitosterol, 7bydroxysitosterol and 3-bydroxystigmast-5-en-7-one, were isolated from the petroleum ether root extract. The present study gives scientific credence to the traditional use of Girardinia diversifolia in the management of microbial infections.

Two pentacyclic triterpenoids were isolated, for the first time, from the stem bark of Blighia unijugata Bak. The structures of the two compounds were elucidated on the basis of their spectral data as friedelin and epifriedelinol.

Two sterols, b-sitosterol and stigmasterol, were isolated from the stem bark of combetrum fragrans~ The, identity.of'.these.compounds was established by spectral analysis.

Three steroidal indoxyls, 3-oxo-16,17-seco-16;.nor-l,4-androstadien-15-(7'-methoxy-2-indoxyliden)17-oic acid, 1-(2'-indoxyliden)-2-nor-l,2-secocholestan-3~ oic acid and 1-(5'- chloro-2-indoxyliden)-2-nor-l,2-secocholestan-3-oic acid were synthesized and screened for anti-inflammatory activity. Their pK. values were also determined using a solubility method. The first compound, 3-oxo-16,17- seco-16-nor-l ,4-androstadien-15-(7' -methoxy-2-indoxyliden) 17 -oic acid, had an EDso value of 15.3 mg/kg and a pK. of 7.09. The cholestane derivative, 1-(2'-indoxyliden)-2-nor-l,2-secocholestan-3-oic acid, and its chloro analogue 1-(5'-chloro-2-indoxyliden)-2-nor-l,2-secocholestan-3-oic acid had EDso values of 16.2 and 22.8 mg/kg, while their pK. values were 6.56 and 7.07, respectively, suggesting that these compounds are relatively weak acids.

5&alpha-Androstan-17&beta-ol-3-one condenses with 2-nitrobenzaldehyde in alkaline conditions to give the steroidal indoxyl 17&beta-hydroxy-1-(3′-oxoindan-2′-yliden)-3-nor-1,2-secoandrostan-3-oic acid (I) which on refluxing with acetic anhydride affords the lactam 17&beta-acetoxy-3′-aza-4a-homoandrost-1-eno-(3,2-a)-indan-3′,4-dione (II). Reduction of I with sodium borohydride gives the indole 17&beta-hydroxy-1-(indol-2′-yl)-3-nor-1, 2-secoandrostan-3-oic acid (III). The results of this synthesis suggest that 3-ketosteroids saturated in ring A react in a similar manner to 17-ketosteroids, with 2-nitrobenzaldehyde.

An isocratic liquid chromatographic method with UV detection at 215 nm, which is suitable for the analysis of azithromycin (AZT) in bulk samples, is described. AZT is separated from its synthesis intermediates and a degradation product as well as from six unknown impurities on an XTerra RP18 column at 70 degrees C using a mobile phase consisting of acetonitrile-pH 6.5 0.2M K2HPO4-water (35:10:55, v/v/v) at 1.0 mL/min. The XTerra stationary phase contains methyl groups that are incorporated in the bulk structure of the material. This allows for special selectivities. Robustness is evaluated by a full factorial design experiment. The method shows good selectivity, repeatability, linearity, and sensitivity.

Ampicillin products, 20 capsules, 2 tablets and 23 dry suspensions were evaluated for quality by liquid chromatography at theDrug Analysis Unit University of Nairobi. Four capsule formulations failed limits on content. The Ampicillin content in 5 suspensions dropped below 80% on storage, but had no correlation to decrease in chemical content
 
Ampicillin is semi-synthetic penicillin used in the management of infections caused by sensitive microorganisms. Microbial resistance against ampicillin is well documented and cross-resistance is a common problem among the penicillins. Development of resistance is always associated with exposure of microorganisms to sub-lethal levels of drugs. The quality administered and especially low content of ampicillin in dosage form could therefore contribute to the development of resistance.
 
Work on the quality of drugs in the period 1982 to 1992 has shown presence of poor quality penicillin products in the market [1-4]. This observation was recently reinforced by the findings on quality of phenoxymethylpenicillin syrups [5]. The extensive use of ampicillin in kenya as one of the drugs on the essential drugs list of Ministry of Health [6] led to observed increase in resistance. It was recently replaced by amoxicillin.
 
The communication presents findings on the quality of ampicillian capsules and tablets and dry syrups found on the Kenyan market using liquid chromatography (LC). The preparations were from private and public sources including those submitted to the ministry of Health drug regulatory authority. The latter are intended for marketing in Kenya after registration, and for the purpose of this paper are treated as being on the market.