Kwabena Ofori-kwakye | Kwame Nkrumah University of Science and Technology (original) (raw)

Papers by Kwabena Ofori-kwakye

Journal of Drug Delivery, 2018

The potential of cocoa pod husk (CPH) pectin-based modified release (MR) capsules as a carrier fo... more The potential of cocoa pod husk (CPH) pectin-based modified release (MR) capsules as a carrier for chronodelivery of hydrocortisone in Sprague-Dawley rats was assessed. Extemporaneously formulated CPH pectin-based hydrocortisone (10 mg) capsules crosslinked with calcium chloride (Formulation A) or zinc (Formulation B) and a commercial immediate release hydrocortisone formulation were administered orally to Sprague-Dawley rats and the pharmacokinetic parameters were evaluated using noncompartmental analysis. Formulation A had a 2 h lag phase followed by an increase in serum drug concentration in the treated rats. Peak concentrations (Cmax) of 21.799 ± 1.993 ng/ml and 20.844 ± 2.661 ng/ml were achieved after 6 ± 0.23 h and 6 ± 0.35 h (Tmax), respectively, for capsules A and B. The immediate release formulation had a peak concentration of 15.322 ± 0.313 ng/ml within 1 ± 0.2 h. The relative bioavailability of the CPH pectin-based capsules A and B was 213% and 274%, respectively. Formula...

Resumen Context: Excipients play a key role in the quality of medicines and contribute to viable ... more Resumen Context: Excipients play a key role in the quality of medicines and contribute to viable delivery systems. This has intensified the search for new natural polymer pharmaceutical excipients. Cocoa pod husks (CPHs) are a rich source of pectin. A study of CPH pectin showed that it possesses the requisite physicochemical properties to be employed as a multi-functional pharmaceutical excipient. However, the safety of this natural polymer has not been evaluated. Aims: To conduct sub-chronic toxic effects of CPH pectin in Sprague Dawley rats to assess its safety as a pharmaceutical grade excipient. Methods: CPH pectin at doses of 0.714, 7.14, and 71.4 mg/kg were administered to male and female Sprague-Dawley rats by oral gavage over a 90-day period. Parameters assessed were food and water intake, urinalysis, serum biochemistry, wet organ weights, histopathology and pentobarbital-induced sleeping time. Results: CPH pectin at the orally administered doses had no significant effects o...

Scientifica, 2021

Okra pectin has been studied as a potential excipient in tablet formulations for pharmaceutical i... more Okra pectin has been studied as a potential excipient in tablet formulations for pharmaceutical industries. Okra is widely grown and available in Ghana and other parts of the world. The prospective use of pectin from okra genotypes grown in Ghana as tablet disintegrants has not been reported. This study aims to determine the potential and comparative disintegrating properties of pectin from five okra genotypes (Abelmoschus esculentus L.) in Ghana using uncoated immediate release paracetamol tablet formulations. The yield of the pectin from the various genotypes ranged between 6.12 and 18.84% w/w. The extracted pectins had pH ranging from slightly acidic to almost neutral (6.39–6.92). Pectin from the various genotypes exhibited good swelling indexes (˃200%), varying solubility in different solvents, and low moisture content (˂20%). Elemental analysis of the extracted pectin from the various genotypes revealed very low levels of toxic metals and micronutrients. Pectin from the various...

There has been an upsurge in the use of herbal medicinal products across both developing and adva... more There has been an upsurge in the use of herbal medicinal products across both developing and advanced countries. Finished herbal products are presented in various dosage forms such as decoctions, herbal powders, alcoholic beverages, capsules, tablets, ointments and creams. The growing demand for herbal medicinal products across the world has resulted in the large scale manufacture of these products. Large scale production leads to longer storage periods which could lead to deterioration of products, thereby compromise product quality with adverse consequences on patient safety. Stability studies on herbal products have become necessary to help determine the shelf-life and enhance product quality at all times during storage periods and usage. Appropriate guidelines for stability testing of finished herbal products provides manufacturers, regulatory authorities and research institutions with a harmonized system for stability testing. This paper presents an overview of the various herb...

South African Journal of Science, 2021

Excipients are the various ingredients, apart from the active pharmaceutical ingredients, which a... more Excipients are the various ingredients, apart from the active pharmaceutical ingredients, which are added to pharmaceutical formulations. Excipients obtained from natural sources are preferred over those from synthetic sources because they are cheap, biocompatible and readily available. Gums are made up of carbohydrate units which are linked by glycosidic bonds. This study was aimed at evaluating the potential binding and disintegrating properties of gum obtained from the bark of Cinnamomum zeylanicum, which was obtained from Effiduase in the Ashanti region of Ghana. The gum was extracted using 96% ethanol and the moisture content, Fourier transform infrared spectroscopy spectra, water holding capacity, swelling index and flow properties of the gum were determined. The gum was used to formulate tablets at different concentrations (10% w/v, 15% w/v and 20% w/v) as binder with acacia as the standard. The gum was also used to formulate tablets at different concentrations (5% w/v, 7.5% ...

Scientific African, 2021

Modern advances in dosage forms require innovative excipients that make them more efficient than ... more Modern advances in dosage forms require innovative excipients that make them more efficient than conventional dosage forms. Natural excipients like gums are known to be cheap, biodegradable, and readily available. However several natural gums are yet to be fully characterized and utilized. This study sought to determine the physicochemical properties of Piptadiniastrum africana (Hook. F.) gum to establish a basis for its pharmaceutical application. The crude Piptadiniastrum africana gum (CPAG) was collected as the natural exudates from the tree bark and observed for its macroscopic features. Physicochemical characteristics such as the moisture content, insoluble matter, and ions as well as pH, swelling index, hydration capacity, solubility, viscosity, flow properties, and rheological behaviour were determined. To assess the chemical and morphological nature of the purified gum, scanning electron microscopy (SEM), nuclear magnetic resonance (NMR) imaging, X-ray diffractogram (XRD), and Fourier Transform Infrared (FT-IR) spectroscopy were employed. CPAG was a pale-dark brown color with an ammoniac smell and a biting taste while the purified Piptadeniastrum africana gum (PPAG) (yield 33.19% w / v) was off white-light brown color with a characteristic smell and bland taste. The moisture content of CPAG and PPAG was determined to be 13% and 8% respectively while the insoluble matter level was 0.31% and 0.12% respectively. Both CPAG and PPAG contained monovalent and divalent metal ions in the order Ca 2 + > Mg 2 + > Fe 2 + > Na + > Cu 2 + > K + > Zn 2 +. The swelling and hydration capacities of CPAG were found to be 1.35 and 4.24 respectively while values for PPAG were determined as 0.22 and 3.8 respectively. PPAG was soluble in both hot and cold water, HCl and chloroform. The gum was determined morphologically to be an amorphous carbohydrate with β-D-mannopyranosyl units attached to repeated units of α-D-galactopyranosyl. This study reveals that the purified gum possesses physicochemical features suitable as an excipient for pharmaceutical use.

Journal of Pharmaceutics, 2017

An isocratic sensitive and precise reverse phase high-performance liquid chromatography (RP-HPLC)... more An isocratic sensitive and precise reverse phase high-performance liquid chromatography (RP-HPLC) method was developed and validated for the determination and quantification of hydrocortisone in controlled-release and conventional (tablets and injections) pharmaceutical preparations. Chromatographic separation was achieved on an ODS (C18), 5 μm, 4.6 × 150 mm, with an isocratic elution using a freshly prepared mobile phase of composition methanol : water : acetic acid (60 : 30 : 10, v/v/v) at a flow rate of 1.0 ml/min. The detection of the drug was successfully achieved at a wavelength of 254 nm. The retention time obtained for the drug was 2.26 min. The proposed method produced linear detectable responses in the concentration range of 0.02 to 0.4 mg/ml of hydrocortisone. High recoveries of 98–101% were attained at concentration levels of 80%, 100%, and 120%. The intraday and interday precision (RSD) were 0.19–0.55% and 0.33–0.71%, respectively. A comparison of hydrocortisone analyse...

Saudi Pharmaceutical Journal, 2016

Development and evaluation of natural gum-based extended release matrix tablets of two model drug... more Development and evaluation of natural gum-based extended release matrix tablets of two model drugs of different water solubilities by direct compression

African Journal of Traditional, Complementary and Alternative Medicines, 2011

This study evaluated the wound healing potential of Spathodea campanulata stem bark in Sprague Da... more This study evaluated the wound healing potential of Spathodea campanulata stem bark in Sprague Dawley rats using the excision wound model. The methanol extract contained glycosides, flavonoids and tannins, and was relatively stable when stored at the room temperature for six (6) months. Solvent-free, semi-solid extract of S. campanulata was incorporated into an aqueous cream and applied (10 % w/w and 20 % w/w) on excision wounds of thirty two (32) rats. Cicatrin ® cream was used as a standard wound healing agent. Prior to the remedial cream application, done later on twice daily, sixteen (16) rats had their wounds infected with Staphylococcus aureus, while in the remaining sixteen the wounds were kept clean. The surface area of the excision wounds was monitored planimetrically every four (4) days until a complete wound closure or healing took place. Excision wounds treated with 20 % w/w Spathodea cream and Cicatrin ® cream showed a rapid and comparable decrease (p > 0.05) in wound size. In uninfected wounds, both 20 % w/w Spathodea cream and Cicatrin ® cream application resulted in ~ 95 %wound closure seen on Day 20, and a complete closure seen on Day 24. In infected wounds, both 20 % w/w Spathodea cream and Cicatrin ® cream administration led to ~ 91 %-wound closure on Day 24 and a complete wound contraction on Day 28. The results of this study justify the folkloric use of S. campanulata stem bark to the effect of wound treatment.

BioMed Research International, 2021

Polymeric materials from plants continue to be of interest to pharmaceutical scientists as potent... more Polymeric materials from plants continue to be of interest to pharmaceutical scientists as potential binders in immediate release tablets due to availability, sustainability, and constant supply to feed local pharmaceutical industries. Paracetamol tablet formulations were utilized in investigating the potential binding characteristics of pectin harnessed from various okra genotypes (PC1-PC5) in Ghana. The pectin yields from the different genotypes ranged from 6.12 to 18.84%w/w. The pH of extracted pectin ranged from 6.39 to 6.92, and it had good swelling indices and a low moisture content. Pectin extracted from all genotypes were evaluated as binders (10, 15, and 20%w/v) and compared to tragacanth BP. All formulated tablets (F1-F18) passed the weight uniformity, drug content, hardness, and friability tests. Based on their crushing strength, tablets prepared with pectin from the various genotypes were relatively harder ( P ≤ 0.05 ) than tablets prepared with tragacanth BP. Tablets pr...

Journal of Pharmaceutics, May 31, 2018

Natural polymer research has recently become the focus of intensive research in the quest for new... more Natural polymer research has recently become the focus of intensive research in the quest for new enabling excipients for novel drugs in pharmaceutical formulation for optimal treatment outcomes. Evaluations of some excipients have shown deleterious haematological effects of varying extents on the safety profile of these excipients. A 90-day subchronic toxicity study was conducted to evaluate the influence of cocoa pod husk (CPH) pectin on indicators for haematotoxicity. Male and female Sprague Dawley rats (SDRs) were fed with CPH pectin in doses up to 71.4 mg/kg. The effects of CPH pectin on the haematological indices, direct and total bilirubin, and the spleen were determined. The results indicated that CPH pectin did not induce any untoward toxic effects on the haematological indices, bilirubin levels, and the spleen. There were, however, elevations in MCV at day 30, which was not sustained after the 90 days. The data obtained from this study did not reveal any remarkable findings of toxicological relevance to the haematopoietic system. can be tailored for diverse applications based on their large chains and functional groups. In addition, they can be modified with low and high molecular weight materials to achieve new materials with varied physicochemical properties [1, 5]. Consequently, the successful development of these polymers as excipients has yielded various applications including matrix controlled system, film coating agents, buccal films, microspheres, nanoparticles, implants, viscosity enhancers, stabilisers, disintegrants, solubilisers, emulsifiers, suspending agents, gelling agents, and binders in drug formulation [6]. Cocoa is an important agricultural and economic crop in Ghana, West Africa. Processing of the cocoa pod husks (CPHs) after removing the cocoa beans to useful products like pectin is a means of adding value to the pod husk

Journal of Drug Delivery

This study evaluated the in vitro potential of cocoa pod husk (CPH) pectin as a carrier for chron... more This study evaluated the in vitro potential of cocoa pod husk (CPH) pectin as a carrier for chronodelivery of hydrocortisone intended for adrenal insufficiency. FTIR studies found no drug-CPH pectin interactions, and chemometric analysis showed that pure hydrocortisone bears closer similarity to hydrocortisone in hot water soluble pectin (HWSP) than hydrocortisone in citric acid soluble pectin (CASP). CPH pectin-based hydrocortisone matrix tablets (~300 mg) were prepared by direct compression and wet granulation techniques, and the tablet cores were film-coated with a 15% HPMC formulation for timed release, followed by a 12.5% Eudragit® S100 formulation for acid resistance. In vitro drug release studies of the uncoated and coated matrix tablets in simulated gastrointestinal conditions showed that wet granulation tablets exhibit greater retardation of drug release in aqueous medium than directly compressed tablets. CASP showed greater suppression of drug release in aqueous medium tha...

Journal of Pharmaceutics

The disintegrant potential of native starches of five new cassava (Manihot esculenta Crantz.) var... more The disintegrant potential of native starches of five new cassava (Manihot esculenta Crantz.) varieties developed by the Crops Research Institute of Ghana (CRIG) was studied in paracetamol tablet formulations. The yield of the starches ranged from 8.0 to 26.7%. The starches were basic (pH: 8.1–9.9), with satisfactory moisture content (≤15%), swelling capacity (≥20%), ash values (<1%), flow properties, and negligible toxic metal ion content, and compatible with the drug. The tensile strength (Ts), crushing strength (Cs), and friability (Ft) of tablets containing 5–10% w/w of the cassava starches were similar (p>0.05) to those containing maize starch BP. The disintegration times of the tablets decreased with increase in concentration of the cassava starches. The tablets passed the disintegration test (DT ≤ 15 min) and exhibited faster disintegration times (p>0.05) than those containing maize starch BP. The disintegration efficiency ratio (DER) and the disintegration parameter...

World Journal of Pharmaceutical Research

Candidiasis is caused by the fungus candida and affects various parts of the body especially the ... more Candidiasis is caused by the fungus candida and affects various parts of the body especially the vagina and the mouth. G-Rea® is a herbal mixture marketed in Ghana for the treatment of various candida infections. G-Rea® is prepared from various parts of four Ghanaian medicinal plants, namely: Hoslundia opposita, Alstonia boonei, Combretum smeathmanii and Securidaca longepedunculata. The current study was to compare the physicochemical and pharmaceutical characteristics of aqueous and ethanolic extracts of these plants and to develop them into vaginal pessaries and oral gels. Dried aqueous (A) and ethanolic (E) extracts were prepared by decoction and cold maceration respectively, and their physicochemical and antimicrobial properties were investigated. Extract (E) was formulated into oral gels and vaginal pessaries using glycerogelatine and theobroma oil as bases. The quality and antimicrobial properties of the formulations were evaluated against a number of microbes. A higher yield ...

International Journal of Pharmacy and Pharmaceutical Sciences

Administering the right doses of oral liquid medications is crucial to achieving therapeutic goal... more Administering the right doses of oral liquid medications is crucial to achieving therapeutic goals. These doses are measured with household spoons and dosing devices enclosed in product packages. We investigated the types of household spoons currently available, the types and extent of inclusion of dosing devices in oral liquid product packages and assessed the accuracy, quality, reliability and acceptability of the household spoons and enclosed devices in dosing oral liquid medications. Close to half (46 %) of orthodox and almost all (97 %) herbal oral liquid remedies in the Ghanaian market did not have enclosed dosing devices and will require the use of other devices mostly household spoons to deliver the required doses in their administration. Many people (95 %) used household spoons in dosing oral liquid medications and some (39 %) actually preferred them to enclosed dosing devices. The household spoons were mostly teaspoons and dessertspoons; tablespoons were very rare. Aside o...

Asian Journal of Pharmaceutical and Clinical Research

The mechanical and coating properties of cashew gum-based films, using paracetamol as a model dru... more The mechanical and coating properties of cashew gum-based films, using paracetamol as a model drug, was investigated. Cashew gum was acidic and the acidity did not markedly change with concentration and storage time. However, gum viscosity increased significantly with concentration and storage time. Swelling index of the gum was ~ 3.3 and was largely unaffected by pH of media used. Free films of cashew gum, cashew gum/hydroxypropyl methylcellulose (HPMC), and cashew gum/ carboxymethyl cellulose (CMC) were prepared by solvent casting using glycerol as a plasticizer and the folding endurance, tensile strength, percentage elongation and Young’s modulus of the films determined. Cashew gum films were smooth, uniform and transparent while cashew gum/HPMC and cashew gum/CMC films lacked uniformity and surface smoothness, respectively. Addition of a plasticizer to the gum imparted flexibility to the films. Increase in cashew gum and plasticizer concentration increased the folding endurance ...

Journal of vector borne diseases, 2012

The artemisinin-based antimalarial medicines are first line medicines in the treatment of severe ... more The artemisinin-based antimalarial medicines are first line medicines in the treatment of severe and uncomplicated falciparum malaria. Numerous brands of these medicines manufactured in various countries are available in the Ghanaian market. The study was aimed at evaluating the authenticity and quality of selected brands of artemisinin-based antimalarial medicines marketed in Ghana. In all, 14 artemisinin-based antimalarial medicines were purchased from pharmacies (P) and licensed chemical shops (LCSs) in the Kumasi metropolis, Ghana. Simple field tests based on colorimetry and thin layer chromatography were employed in determining the authenticity of the samples. Important quality assessment tests, namely uniformity of mass, crushing strength, disintegration time, and the percentage content of active pharmaceutical ingredients (APIs) were determined. All the brands tested contained the stipulated APIs. Artesunate tablet AT2 failed the uniformity of mass test while artesunate table...

jpsr.pharmainfo.in

The aim of this study was to assess the physicochemical and microbiological quality of the source... more The aim of this study was to assess the physicochemical and microbiological quality of the sources of household water supply and the prevalence of diarrhoea in three peri-urban communities in Kumasi, Ghana. Nine water sources, four from hand dug wells and five from boreholes, were identified, sampled and analysed for physicochemical (colour, turbidity, total dissolved solids, conductivity, and acidity) and microbiological characteristics. The total dissolved solids and conductivity values determined were within the WHO limit but the turbidity and colour of two of the water sources exceeded the WHO limits. All the water sources were acidic and did not meet the WHO specification for pH for drinking water. Faecal coliforms and faecal streptococci were consistently present in the water sources at levels signifying human pollution. Diarrhoea cases among children < 5 years reported at the various health facilities within the studied communities increased during periods when high levels of microbial contamination in drinking water sources were recorded. Provision of potable household water should continue to be the priority of governments of developing countries, especially those in sub-Saharan Africa, to reduce the prevalence of water-borne diseases.