Aqueous solubility of ciprofloxacin in the presence of metal cations

Purpose: Though the complexation of ciprofloxacin with metal cations has been extensively studied, the effect of this complexation on the aqueous solubility of ciprofloxacin which is an important factor affecting drug distribution has not been well documented. We have thus set out in this study to investigate the aqueous solubility of ciprofloxacin in the presence of metal cations. Method: The measurements were done spectrophometrically after shaking ciprofloxacin alone or in the presence of varying amounts of different metal cations for five hours to attain equilibrium. The amount of ciprofloxacin in the saturated solution in each case was then measured spectrophotometrically Results: The solubility of ciprofloxacin in 0.05M H2SO4 at 37.0 ± 0.20C was 46.65 mgml-1 (0.12M). Except for magnesium sulphate, all the cations investigated progressively increased the aqueous solubility of ciprofloxacin. Ferrous ion had the greatest increase. It was followed by ferric, calcium and aluminium ions. Potassium and sodium ions had very slight increase in ciprofloxacin solubility. As the amount of magnesium sulphate increased, the aqueous solubility of ciprofloxacin increased slightly initially but then decreased progressively. Conclusion: The observed solubility profiles can be attributed to the type and extent of complexes formed between ciprofloxacin and the metal cations. This increase in the aqueous solubility of ciprofloxacin can have profound effect on the enteric absorption of ciprofloxacin and on its antibacterial activity when these metal cations are present, and may contribute to the observed poor availability and antibacterial activity of ciprofloxacin when co-administered with these cations. Keywords: Ciprofloxacin, aqueous solubility, ciprofloxacin-metal cation, interaction, antibacterial activity, gastrointestinal absorption.> Tropical Journal of Pharmaceutical Research Vol. 4 (1) 2005: pp. 349-35

Comparative evaluation of selected starches as adsorbent for Thin-layer Chromatography

Purpose: A variety of tested organic and inorganic adsorbents are available today specifically for thin-layer chromatography. The most commonly used is silica gel which is an inorganic adsorbent. Organic substances like cellulose, polyethylene are also used. All these are imported into Nigeria and are unhealthy for economic policies. Most commonly used adsorbent may not be easy to produce locally, but starch, which is a very common product, can be made very readily available. Method: Comparative tests were carried out on cassava, guinea corn and irish potato starches to evaluate and determine suitability as adsorbents for thin-layer chromatography. The starches were used in their natural forms and various modified forms:- formamide, paraffin-impregnated forms and derivatized forms so as to exhibit different properties using different solvent systems to separate different classes of compounds namely alkaloids, amine acids, lipids and steroids with silica gel as standard. Results: The results obtained have proved starch to be a suitable adsorbent both in its naturally occurring and modified forms. Good separations of amino acids and steroids were obtained on natural layers when compared with silica gel, while alkaloids on formamide-impregnated layers and lipids on paraffin-impregnated layers also gave encouraging results. The acetylated starch by suitable modification should produce good results. Conclusion: The suitability of natural starches and its modifications as adsorbents for TLC has thus been established and seems very promising for future use. Keywords: Starch, cassava, guinea corn, Irish potato, adsorbent, thin-layer chromatography. > Tropical Journal of Pharmaceutical Research Vol. 4 (1) 2005: pp. 331-33

Identification of Counterfeit Drugs by Community Pharmacists in Lagos State

Purpose: The problem of fake and counterfeit drugs is real and constitutes a major threat to the health and safety of the Nigerian population. A descriptive study was carried out to assess the methods of identification of counterfeit drugs by community pharmacists in Lagos State. Methods: The research instrument was a 23-item questionnaire, which was administered to consenting community pharmacists in 17 out of the 20 Local Government Areas in Lagos State. A convenient sample of practicing community pharmacists both in retail and wholesale distribution of pharmaceutical products were recruited into the study using a list of registered pharmacists from the Association of Community Pharmacists in Lagos State. Effort was made to ensure adequate representation of Pharmacies in every local government area in Lagos State. Results: All the respondents agreed that there is a fake and counterfeit drug problem in Nigeria, and (74%) considered this a major problem. The respondents commonly used visual security techniques before drug purchasing. These were: Seals/embossments (83%), character of print (77%), and Holograms (68%).The respondents' most likely action after a counterfeit drug encounter was to return the drug back to the supplier. Conclusion: The study showed that pharmacists sampled were aware of the prevalence of fake and counterfeit drugs and quite a number of them have had encounters with them. There is an indication that the respondents try to assure themselves of the quality of the drugs they purchase by use of several methods. However, no rigorous effort was taken to confirm as well as report suspected fake and counterfeit drugs to regulatory authorities. Keywords: Community pharmacists, drug identification, fake and counterfeit drugs. > Tropical Journal of Pharmaceutical Research Vol. 5 (1) 2006: pp. 545-55

Assessment Of The Microbial Load And Some Physico-Chemical Parameters Of Some Finished Herbal Liquid Products

 Despite the benefits derived from herbal products, they may be contaminated with various impurities. It is therefore important to assess the microbial quality and heavy metal content of herbal preparations, especially liquid preparations and determine their safety profile. Herbal liquid preparations made locally by herbalists and sold to patients in herbal homes were used for this study. One bottle of each of seventeen (17) different liquid herbal preparations was purchased. From each bottle, three aliquot samples were assessed for microbial presence and total viable count. Isolation and identification of the contaminants were also carried out, while other determinations like pH, phytoconstituents, heavy metal and elemental contents were performed using standard methods of analyses. Results showed that, 4 (23.53%) had no microbial contaminants, while 13 (76.47%) were contaminated with various microbes. Of these contaminated preparations, 10 (58.82%) had single contaminants each, of which 1 (10%) had Staphylococcus aureus; 2 (20%) had Escherichia coli; 2 (20%) had Pseudomonas aeruginosa and 5 (50%) had Candida albicans. The remaining 3 (17.65%) had 2 contaminants each, of which 1 (33.33%) had E. coli and P. aeruginosa; 1 (33.33%) had E. coli and Staph. aureus; and 1 (33.33%) had Klebsiella pneumonia and Candida albicans. Total viable count and pH values of the different preparations ranged from 1.75 x 105 – 7.50 x 108 organisms/ml and 3.63 – 8.89, respectively. Phytochemical analysis revealed the presence of useful phytoconstituents while elemental analysis revealed the presence of valuable elements whose values all fall within stipulated limits. Thus, the presence of microbes (above limits specified) in a greater percentage of the preparations despite the presence of useful phytoconstituents and elements, could adversely affect the health status of consumers of such herbal liquid preparations. Keywords: Assessment, Microbial load, Physico-Chemical parameters, Herbal products

Evaluation of the pH, titratable acidity and ascorbic acid content of juices commonly consumed by children

Juices are beverages that are consumed by many individuals on a daily basis with children being one of the highest consumers. Juices are obtained by extracting the natural liquid out of fruits or vegetables. This in vitro study aims to evaluate the endogenous pH, titratable acidity and ascorbic acid content of juices commonly consumed by children. Fifteen (15) commonly consumed juices were evaluated. The pH of each juice was determined using a digital pH meter. The titratable acidity was assessed by titrating 0.1 N sodium hydroxide solution against 30 ml of each juice until the end point was reached. The ascorbic acid content of 10 of the juices was determined by iodometric titration. The pH of the evaluated samples ranged from 3.40 to 5.74, with 93% of the juice samples having pH values less than the critical pH (5.5). The titratable acidity of the juice samples also ranged from 5.43 g/100 ml to 2.14 g/100 ml. Of the juice samples, 33.33 % did not contain ascorbic acid but for the others, the ascorbic acid level ranged from 6.739 mg/100 ml to 1 mg/100 ml. All juices were acidic. Keywords: Fruit juice, pH, titratable acidity, ascorbic acid conten

Comparative determination of chlorpromazine hydrochloride content in multi-sourced chlorpromazine tablets in Nigeria

Purpose: Although different brands or unbranded chlorpromazine tablets from multiple sources are available in Nigeria today, they must all contain the same active principle and satisfy the standards of quality, efficacy and safety. This study is designed to check for possible faking and adulteration of chlorpromazine tablets and also establish the possibility of inter-brand substitution based on drug content (chemical equivalence). Method: The determination of the chlorpromazine hydrochloride content was carried using non-aqueous titrimetric and spectrophotometric methods. Glacial acetic acid and acetone were used as the non-aqueous solvent and equivalence points were determined using visual indicators and potentiometer. Results: The results obtained showed that all the brands analyzed met the specification of the British Pharmacopoeia and so contain acceptable amounts of chlorpromazine drug content thus enabling possible brand substitution. Statistical comparison showed no significant difference between the results obtained by determining end-point using visual indicators and the potentiometer. Conclusion: The use of the visual indicator method is recommended for fast and accurate routine laboratory analytical work especially in developing nations. Keywords: Chlorpromazine, non-aqueous titration, spectrophotometric determination, potentiometr

Determination of trace metals presence in drinking water and fruit juice in Benin City, Nigeria

ABSTRACT Objective: To study the levels of trace metals drinking water and fruit juice in Benin City, Nigeria. Methodology and results: Fifteen water samples and 10 fruit juice samples were analyzed using Atomic Absorption Spectrophotometry (AAS) and the metallic elements Chromium (Cr), Copper (Cu), Iron (Fe), Lead (Pb), Manganese (Mn) and Zinc (Zn) measured. Fe was present in all the samples, Cu was present only in the drinking water samples, Mn and Zn were found in all drinking water samples and only three fruit juice samples. Pb and Cr were below the detection limits in all the samples. Conclusion and application of findings: The trace metal levels in all the samples were below the allowable limits set by the National Research Council and WHO (1996) except in the case of one sample where the concentration of Zn (5.696 mg/L) was above the allowed limit and hence the product is unsafe for human consumption

Research Article - Comparative evaluation of selected starches as adsorbent for Thin-layer Chromatography

Purpose: A variety of tested organic and inorganic adsorbents are available today specifically for thin-layer chromatography. The most commonly used is silica gel which is an inorganic adsorbent. Organic substances like cellulose, polyethylene are also used. All these are imported into Nigeria and are unhealthy for economic policies. Most commonly used adsorbent may not be easy to produce locally, but starch, which is a very common product, can be made very readily available. Method: Comparative tests were carried out on cassava, guinea corn and irish potato starches to evaluate and determine suitability as adsorbents for thin-layer chromatography. The starches were used in their natural forms and various modified forms:-formamide, paraffin-impregnated forms and derivatized forms so as to exhibit different properties using different solvent systems to separate different classes of compounds namely alkaloids, amine acids, lipids and steroids with silica gel as standard. Results: The results obtained have proved starch to be a suitable adsorbent both in its naturally occurring and modified forms. Good separations of amino acids and steroids were obtained on natural layers when compared with silica gel, while alkaloids on formamide-impregnated layers and lipids on paraffin-impregnated layers also gave encouraging results. The acetylated starch by suitable modification should produce good results. Conclusion: The suitability of natural starches and its modifications as adsorbents for TLC has thus been established and seems very promising for future use