Pharmaceutics and Pharmaceutical Technology- Scholarly Publications
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- ItemOpen AccessEffects of paraffin coatings on the shearing properties of lactose(J. Pharm. Pharmacol., 1982) Irono, C.I; Pilpel, NAn annular shear cell has been employed to measure the shearing properties of lactose powder coated with up to 10-4 mol g-l of powder of a series of paraffin hydrocarbons. The angle of internal friction, Δ, of the coated powders was independent of their packing density. The shearing properties of the powders depended on the concentration, the viscosity and thickness of the coating material.
- ItemOpen AccessEffects of coating the powder on the tensile strength, disintegration and dissolution of lactose tablets(lnternational Journal of Pharmaceutics, 1983) Igwilo, C.I; Pilpel, NA study has been made of the effects produced on the tensile strength, disintegration and dissolution of lactose tablets by coating the powder with increasing amounts of paraffins. Addition of paraffins reduces the tensile strength and prolongs the disintegration and dissolution times. Silicones produce similar effects on the disintegration times. The disintegration and dissolution results have been explained in terms of the changes produced by the coatings on the wettability of the powder.
- ItemOpen AccessDissolution mechanism of tablets produced from coated lactose powder(1987) Igwilo, C.I.; Pilpel, N.The use of the equation of Kitazawa et aJ in the analysis of the dissolution process of tablets produced from lactose powder coated with paraffin has suggested either an initial breaking of the tablets into particles that subsequently break down into smaller particles or a progressive breaking of the tablet into smaller particles. The former produces a change in rate constant from k1 to k2. Diluents (for example, lactose) included in the formulation of low dose potent drugs provide the main bulk of a tablet and play a significant role in the release of the drug substance (Wagner 1971). The wettability of the tablet surface also influences its disintegration and dissolution and subsequent release of the active ingredient. This report deals with the probable mechanisms involved in the dissolution of tablets produced from lactose powder coated with paraffins.
- ItemOpen AccessA consideration of the range and strength of interparticle forces in coated lactose powder(J. Pharm. Pharmacol., 1988) Igwilo, C.I; Pilpel, NA study has been made of the range and strength of interparticle forces in lactose powder coated with increasing concentrations of paraffins at different temperatures. Marked changes occurred in these forces as the paraffin content was altered and the temperature increased from - 100 to +SO'c. The strength and range of interparticle forces depended on the mechanical properties of the coating materials and the surface free energy of the coated powders.
- ItemOpen AccessA consideration of the range and strength of interparticle forces in coated lactose powder(1988) Igwilo, C.I.; Pilpel, N.A study has been made of the range and strength of interparticle forces in lactose powder coated with increasing concentrations of paraffins at different temperatures. Marked changes occurred in these forces as the paraffin content was altered and the temperature increased from - 100 to +SO'c. The strength and range of interparticle forces depended on the mechanical properties of the coating materials and the surface free energy of the coated powders.
- ItemOpen AccessNew Method of Evaluating Perfumery Raw Materials: PART II in Cosmetic Products(The Nigerian Journal of Pharmacy, 1989) Igwilo, C.I; Adeyemi, M; Oguntimein, BThe new alignment chart method has been used in the evaluation of the fragrances of the essential oils from C. citratus (Dc) stapf, E. uniflora linn, L. adoensis Hochst, V. agnuscastus Linn and Z. rigidifolium waterman in cosmetic products. The method incorporates the retentivity index, RF acceptability index, RA and the final performance, Fp. The consistency of the cosmetic products seem to have some effects on the Rf values but very little or no effects on the RA values.
- ItemOpen AccessEffects of molecular coatings on the compression and tableting of some pharmaceutical powders(lnternational Journal of Pharmaceutics, 1991) Pilpel, N; Igwilo, C.I; Malamataris, SCoating the particles of various pharmaceutical powders with up to 10 molecular layers of paraffins, fatty acids, surfactants, silicones and polymers noticeably alters their mechanical behaviour when they are compressed into beds or formed into tablets. At low packing fractions of 0.41 the tensile strengths of the beds tend to increase, then decrease and then increase again with increasing coating concentration. At higher packing fractions of 0.82 the tensile strengths of tablets generally decrease with coating concentration and there is an inverse relationship between their tensile strength and the ratio of the elasticity to the compression of the coated powders.
- ItemOpen AccessEffect of Cream Bases on the Antimicrobial Properties of the Essential Oil of Aframomum meleguata(Int. J. Pharmacognosy, 1991) Igwilo, C.I; Akpan, U.E; Adeoye, A.O; Ilozor, C.NThe antimicrobial properties of the essential oil of Aframomum meleguata (AMO) and the effect of cream bases on these properties were investigated using both Agar dilution and diffusion methods. The oil was found to be most active against gram positive bacteria with a MIC of 0.001 % v/v against S. aureus and B. subtilis. C. albicans was inhibited at 0.5% v/v while Ps. aeruginosa and E. coli were each inhibited by 1.0% v/v, The release rate of the oil from the water soluble cream bases, Cetomacrogol or Aqueous cream was greater than that from the hydrocarbon cream base, oily cream due to the hydrophobicity of the oily cream.
- ItemRestrictedDirect Compression Studies on Low-Cost Cellulose derived from Maize Cob.(1994) Okhamafe, A.O.; Azubuike, C.P.α-Celluloses were extracted from both the white and yellow varieties of de-grained corn cob, and then evaluated as direct compression diluents in paracetamol tablets using microcrystalline cellulose (Avicel®), a commercial diluent, as a standard. Based on the physicochemical and tablet parameters examined, e.g., tensile strength, disintegration time and dissolution, the extracted celluloses compared well with microcrystalline cellulose (MCC). They were highly compressible no binding agent was needed, and yielded paracetamol tablets that were self-lubricating (no lubricant was added), rapidly self-disintegrating (a disintegrant was not required) and facilitated high in vitro drug availability. The tablets were free from physical defects. Furthermore, the production costs of the extracted celluloses were substantially lower than the cost of MCC. The findings from this work further demonstrate the greater pharmaceutical potential of cellulose derived from agricultural wastes
- ItemOpen AccessComparative Assessment of Fragrances obtained from Nigerian plants(J. West Afr. Pharm., 1995) Igwilo, C.I; Adeoye, A; Nasipuri, R.N; Kabele-Toge, B.B; Popoola, A.OEssential oils from Cestrum nucturnum and Plumera rubra ( varacuminata) were obtained by hot enfleurage and those from Cymbopogon citratus and Eugenia uniflora were obtained using the steam distillation method (B.P. 1980). Measurement of the odour of the fragrances was carried out by the dilution and perfume slip methods. The acceptability of the fragrance was investigated using both the 'Yes' and 'No' method and the Hedonic odour rating scale with the participation of fifty (50) observers. The alignment chart method and Hedonic odour rating scale were used in the evaluation of the fragrances. A correlation seems to exist between the final performance (Fp) obtained from the alignment chart and the number of judgements from the Hedonic odour rating scale. This suggests that the methods used were reproducible and that bias was greatly reduced. The oils were found to have great potentials as fragrances.
- ItemOpen AccessComparative Assessment of Fragrances obtained from Nigerian plants(J. West Afr. Pharm., 1995) Igwilo, C.I; Adeoye, A; Nasipuri, R.N; Kabele-Toge, B.B; Popoola, A.OEssential oils from Cestrum nucturnum and Plumera rubra ( varacuminata) were obtained by hot enfleurage and those from Cymbopogon citratus and Eugenia uniflora were obtained using the steam distillation method (B.P. 1980). Measurement of the odour of the fragrances was carried out by the dilution and perfume slip methods. The acceptability of the fragrance was investigated using both the 'Yes' and 'No' method and the Hedonic odour rating scale with the participation of fifty (50) observers. The alignment chart method and Hedonic odour rating scale were used in the evaluation of the fragrances. A correlation seems to exist between the final performance (Fp) obtained from the alignment chart and the number of judgements from the Hedonic odour rating scale. This suggests that the methods used were reproducible and that bias was greatly reduced. The oils were found to have great potentials as fragrances.
- ItemOpen AccessA Comparative Bioavailability Study of Paracetamol Tablet and Suppository Formulations(West Afr. J. Pharm., 1997) Igwilo, C.I; Taylor, O; Silva, B.O; Coker, H.A.B; Soremekun, RThe bioavailability of 2 different paracetamol suppository formulations were compared with that of a standard paracetamol tablet formulation in 10 healthy adult volunteers. Paracetamol was rapidly and completely absorbed from both the tablet and suppository forms. The rate of absorption was faster from the tablet form than the suppository form. Although formulation C had a slower initial release of paracetamol than formulation A, its relative bioavailability was greater. The effective concentration of paracetamol in the blood was rapidly attained and maintained for about 6 hours.
- ItemOpen AccessCharacterization Of Some Nigerian Gums Towards Their Utilization As Pharmaceutical Excipients(Nig. Qt. J. Hosp. Med., 2000) Igwilo, C.I; Odusote, M.O; Abioye, A.OGums were extracted locally from the stems and seeds of some plants, Some of their physicochemical properties were evaluated. The parameters evaluated for the physicochemical data of the gum powders include: Appearance, texture, colour, odour, pH, Ash value, Alcoholic extractives, crude fibre content, protein content, viscosity and swelling index. The percentages of the natural elements present in the gums like potassium, sodium, magnesium, calcium, iron, zinc, manganese, copper, phosphorus and nitrogen were determined using atomic-absorption spectrophotometry. The monosaccharide content were evaluated and compared using HPLC. The possible effectiveness of the gums in pharmaceutical suspensions were computed by determining their rheological properties. Such parameters like viscosities of their aqueous mucillages were determined using Brookfield Digital viscometer. All their rheograms exhibited pseudoplastic flow properties typical of good suspending agents, The results were compared graphically and the results labelled. Some of the gums like Cissus populnea, Raphia vinifera, Mucuna flagillepes exhibited thixotropy as their down curve did not fall on the up curve. Only palm kernel cake gum did not show thixotropy. Since thixotropy is a measure of the structural breakdown of suspension, the higher the thixotropic index, the better the suspending activity of the gum. The yield (% w/w) of Cissus populnea was 14.98 ± 0.77. the whole exudate of Raphia vinifera produced fine gum. Only 2.86 ± 0.17% yield as obtained for Mucuna flagillepes. Palm kernel cake gave 0.94 ± 0.20% gum. From the above study, it appeared as if Cissus populnea gum exhibited the highest viscosity imparting property, and highest thixotropic index compared weight in weight with the other guns studied. Raphia vinifera gum however offered the highest yield but higher quantity appeared to be needed to produce similar effect with Cissus populnea. Future work on the gums would choose the most viable for the Nigerian Market.
- ItemOpen AccessDrug Production in Tertiary Health Institutions - Needs, Constraints and Prospects(Nig. Qt. J. Hosp. Med., 2005) Adeoye, A.W; Igwilo, C.IThis study was carried out to investigate the needs, problems and prospects of drug production in tertiary health institutions using Lagos University Teaching Hospital as a case study and to recommend solutions to the problems so identified. The use of questionnaires was employed in the study covering all pharmacists in the pharmaceutical services department, pharmacy technicians and quality control technologists in the Drug Production unit of the hospital. It was unanimously agreed by the respondents that local production was necessary in tertiary hospitals. About two third of the respondents considered the current performance of the Drug production unit to be at most, average. The major problems were identified to be lack of adequate funding, inadequate support and commitment by the hospital management and absence of maintenance culture leading to breakdown and collapse of equipment and machinery. It was realized that the prospect of drug production in tertiary health institutions was very bright and that success could be achieved, but only through very careful planning and execution of the project, adequate funding, strong commitment from the management of the institution, well trained and motivated staff.
- ItemOpen AccessAre High Potency Multivitamin Syrups Toxic(Nigerian Quarterly Journal of Hospital Medicine, 2005) Mendie, U.E.; Emeka, P.M.; Banjo, A.F.Background: High potency liquid multivitamin preparations contain many active vitamin ingredients having maximal daily dosage and formulated for prolonged administrations. They are intended to be used as food supplements and in the treatment or prophylaxis of vitamin deficiencies. Multivitamin preparations are highly nutritive products containing mixtures of parabens as preservatives, or used as appetizers. Parabens are highly active against most bacteria, yeast, and moulds. Vitamin ingredients are hardly toxic when used individually; nonetheless, when formulated to contain a high concentration of multivitamin ingredients, the possibility of its toxicity cannot be ignored. Study design: The toxicity of test multivitamin syrup containing 10 ingredients has been evaluated using acute and sub-acute toxicity studies. Results: Our results showed that the LD50 of the preparation following oral administration in albino rats with average weight of 184.5g was found to be 8.53ml. An equivalent amount of this toxic dose volume in 70g adult human subject will give a value of 3236.31ml implying a relatively harmless product. Generally, there was a significant (P<0.05) dose dependent increase in body weight of the rats implying that multivitamin syrups can serve as a food supplement. The haematological parameters including Hb, PCV, and WBC counts showed significant increases (P<0.05) indicative of a stimulatory effect on erythropoiesis and WBC formation. No toxic effects were observed in the systemic organs such as the liver, heart, kidney, and spleen which showed no marked changes in their sizes or histologies. Conclusion: Based on these findings, multivitamin syrup containing up to 10 ingredients apart from serving as food supplements is safe for short and long-term administration.
- ItemOpen AccessContributions of fluoride to the sensitivity of oral isolates to some anti-microbial agents(African Journal Online(Nigerian Dental Journal), 2007) Mendie, U.E.Objective: Plaque formation on teeth surfaces, gingivitis, and caries has been associated with the presence and activities of oral flora; and several agents have been demonstrated to exhibit anti-plaque potentials. This study is designed to evaluate the inhibitory potentials of some agents on fluoride-exposed and non-exposed oral isolates capable of causing dental plaque and infections. Method: Agar dilution method was used to determine the Minimum Inhibitory Concentration (MIC) of triclosan, ampicillin, and chlorhexidine against fluoride-exposed and non-exposed Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, Bacillus subtilis, and Candida albicans. Results: All the agents showed remarkable antimicrobial activities against fluoride-exposed oral isolates. Our study also showed a 75% decrease (p<0.05) in the MICs of all the agents used against the test organisms after 4 weeks of exposure to 0.11w/w% fluoride. In contrast, the MIC of the non-exposed isolates were significantly higher(p<0.05) and did not change throughout this period. Triclosan and chlorhexidine showed, in addition to their antibacterial activities, outstanding antifungal action resulting in a more than 93% increase in the susceptibility of Candida albicans. These observations may be attributable to the synergistic effect of fluoride on the antimicrobial activity of these agents. Conclusion: It can be inferred from this study that regular daily use of fluoride-containing dentifrice having antimicrobial agents such as triclosan or in conjunction with mouthwash containing chlorhexidine will aid in the prevention of plaque formation.
- ItemRestrictedPrevalence of Some Uropathogenic Bacterial Isolates and their Susceptibility to Some Quinolones(Ibadan Biomedical Communications Group, 2007-09) Idowu, A.O.; Odelola, H.OBacterial Isolates of different Genera were collected from suspected cases of Urinary tract infection in Ibadan and their prevalence was determined. Sensitivity pattern of the organisms to quinolone antibacterial agents was also investigated by the antibiotic disc diffusion method using Kirby Bauer method. The study revealed the prevalence of uropathogenic organisms as follows:- Escherichia coli (46.2%), Klebsiella spp (23.1%), Staphylococcus aureus (21.1%) and Pseudomonas aeruginosa (9.6%). The quinolones were found to be highly effective against all the organisms. The average percentage susceptibility of the organisms were as follow: Staphylococcus aureus (92.7%) Escherichia coli (81.7%), Pseudomonas aeruginosa (76.0%), and Klebsiella spp (70.0%). As indicated by their high activity, quinolones are better alternatives to commonly prescribed antibiotics in Urinary tract infection therapy although caution must be exercised in their prescription as the emerging low level of resistance may portend great danger for their future use.
- ItemOpen AccessPhytochemical screening and antioxidant activities of some selected medicinal plants used for malaria therapy in Southwestern Nigeria(Tropical Journal of Pharmaceutical Research, 2008) Ayoola, G.A.; Coker, H.A.B.; Adesegun, S.A.; Adepoju-Bello, A.A.; Obaweya, K.; Ezennia, E.C.; Atangbayila, T.O.Purpose: Oxidative stress has been shown to play an important role in the development of anaemia in malaria. Indeed, increase in total antioxidant status has been shown to be important in recovery from malaria. The antioxidant activities of four medicinal plants traditionally used in the treatment of malaria in southwestern Nigeria were determined. Methods: The ethanolic extracts of the leaves of Carica papaya Linn. [Caricaceae] , stem bark of Magnifera indica Linn. [Anacardiaceae], leaves of Psidium guajava Linn. [Myrtaceae] and the leaves of Vernonia amygdalina Del. [Compositae], were used in the present study. The plant parts commonly used in the locality in malaria therapy were employed in this study. The plants were screened for the presence of phytochemicals and, their effect on 2,2-Diphenyl-1-picryl-hydrazyl radical (DPPH) was used to determine their free radical scavenging activity. Results: Phytochemical screening of the plants showed the presence of flavonoids, terpenoids, saponins, tannins and reducing sugars. M. indica did not contain cardiac glycosides and alkaloids while, P. guajava also showed the absence of alkaloids and anthraquinones. Anthraquinones was similarly absent from V. amygdalina. Concentrations of the plant extracts required for 50% inhibition of DPPH radical scavenging effect (IC50) were recorded as 0.04 mg/ml, 0.313 mg/ml, 0.58 mg/ml, 2.30 mg/ml and 0.054 mg/ml for P. guajava, M. Indica, C. papaya, V. amygdalina and Vitamin C, respectively. Conclusion: All the plants showed potent inhibition of DPPH radical scavenging activity, P. guajava being the most potent. The free radical scavenging (antioxidant) activities of these plants probably contribute to the effectiveness of the above plants in malaria therapy.
- ItemOpen AccessEvaluationof antibacterial activity, acute toxicity in mice and phytochemical profiles of hydroethanolic extract of Stachytarphetaangustifolia (Mill) Vahl. Plant .(2008) Enwuru N.V; Ogbonnia S.O; Nkemehule F.; Enwuru C.A; Tolani O.The aim of this study was to evaluate antibacterial activity, acute toxicity in mice and phytochemical profiles of hydroethanolic extract of Stachytarpheta angustifolia plant. The plant S. angustifolia has attracted the attention of the researchers because of its use as an anti-infection agent. The aqueous ethanol (80%) extract of the powdered dried whole plant was obtained by maceration. The bacteria organisms tested include Shigella dysentriae (ATCC 32412), Salmonella typhi (ATCC 213415), and the following clinical isolates: coagulase-negative Staphylococcus, Staphylococcus aureus, Proteus mirabilis, Klebsiella species and Escherichia coli. Susceptibility test, acute toxicity test and phytochemical screening of the plant extract were performed using standard procedures. The results showed that the extract had a good antibacterial activity against S. aureus, S. dysentriae, coagulasenegative Staphylococcus and Proteus mirabilis. The minimum inhibitory concentration (MIC) was found to be between 11.6 and 14.0 mg/ml for the susceptible organisms. The extract exhibited minimum bactericidal concentration (MBC) of 150 mg/ml against S. dysentriae only while other susceptible tested bacteria strains required higher concentrations. The median acute toxicity value (LD50) of the extract was determined to be 8.721 g/kg body weight indicating the extract as being slightly toxic. The extract contained triterpenoid saponins as the major bioactive constituent.
- ItemOpen AccessScreening of Some Medicinal Plants Used in South-West Nigerian Traditional Medicine for Anti-Salmonella typhi Activity(Taylor & Francis Online(Journal of Herbal Pharmacotherapy), 2009-08-20) Akinyemi, K.O.; Mendie, U.E.; Smith, S.T.; Oyefolu, A.O.; Coker, A.O.Ten Nigerian medicinal plants used traditionally for the treatment of several ailments of both microbial and non-microbial origins were tested on multi-drug resistant S. typhi(MDR) strains of which six of them were active. The results revealed that both the aqueous and ethanol extracts of Terminalia avicennioides, Momordica balsamina, Combretum paniculatum and Trema guineensis were effective on the MDR-S. typhi strains with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values ranging from 9.60 to 14 mcg/ml and 24 to 33 mcg/ml, respectively. Whereas, only the aqueous extracts of Morinda Ocimum gratissimum were found to be active against this pathogen with MIC and MBC values of 9.60 and 24 mcg/ml for M. lucida, 40 and 55 mcg/ml for O. gratissimum, respectively. There was no statistical significant difference (P > 0.05) between the activity of each plant extract and the decoctions prepared from them. All the six active plants showed positive reactions to alkaloids, tannins, flavonoids and anthraquinones but in variable degrees. All but M. balsamina, indicated the presence of saponin.