John Ogbonna

University of Nigeria | UNN · Department of Pharmaceutics

Designing oral formulations for children is very challenging, especially considering their peculiarities and preferences. The choice of excipients, dosing volume and palatability are key issues of pediatric oral liquid medicines. The purpose of the present study is to develop an oral pediatric solution of a model bitter drug (ranitidine) following...

This chapter X-rayed antimalarial drug resistance (ADR) by plasmodium species with a particular focus on P. falciparum, which is the most deadly species of the malaria parasite responsible for over 90% of the global malaria burden domiciled in Sub-Saharan Africa. The introduction intently looked at malaria therapeutics across the decades and the de...

Quinine (QHCl) as an antimalarial drug has remained very relevant 400 years after its effectiveness was discovered. Unlike other antimalarials, the development of resistance to quinine has been slow. Hence, this drug is till date still used for the treatment of severe and cerebral malaria, for malaria treatment in all trimesters of pregnancy, and i...

Dermal injuries (e. g., trauma, surgical incisions, and burns) are burdensome health care issues in the world. The delayed healing process can be caused by aerobic and anaerobic bacteria infections, including Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus and Enterococcus species, Pseudomonas aeruginosa, Peptostreptococcus, and Co...

The outbreak of the COVID-19 pandemic in 2019 has been one of the greatest challenges modern medicine and science has ever faced. It has affected millions of people around the world and altered human life and activities as we once knew. The high prevalence as well as an extended period of incubations which usually does not present with symptoms hav...

Aim: Anterior eye segment disorders are treated with eye drops and ointments, which have low ocular bioavailability necessitating the need for improved alternatives. Lipid microsuspension of gentamicin sulphate was developed for the treatment of susceptible eye diseases. Materials & methods: Lipid microsuspensions encapsulating gentamicin sulphate...

Purpose: To increase the solubility of artemether (ART) in Transcutol® HP through microencapsulation in sodium alginate polymer to achieve sustained in vivo release.Method: Graded concentrations of ART (0.00, 0.25, 0.50, 0.75, and 1.00 g) microcapsules were produced using Tween® 80 by the cold homogenization method at 24 x 1000 rpm for 15 min. Char...

Malaria, a leading cause of mortality and morbidity in the developing world, with children aged under 5 years, accounts for 61% of all the global malaria deaths. The World Health Organization approved fixed-dose first-line artemisinin-based combination therapy (ACT) – artemether-lumefantrine for effective malaria treatment, is challenged by poor aq...

The use of repellents has shown to be a practical and economical way of preventing mosquito-transmitted diseases. The aim of the study was to design, formulate and characterize Azadirachta indica (neem) oil based solid lipid microparticulate (SLMs) creams and thereafter evaluate its repellent activity against the Aedes aegypti mosquito. The oil was...

A 2³ Factorial design of cissus-gelatin B polymer blends was developed to formulate amodiaquine HCl-artesunate (AQ-AS) microparticles by varying the polymer blend concentration (2 %w/v, 5 %w/v), crosslinking time (0.5 h, 1 h) and glutaraldehye volume (0.5 ml, 1 ml). The formulations were evaluated using drug entrapment efficiency (EE), particle siz...

Purpose: To develop a simple vanadometric spectrophotometric method for the assay of timolol. Methods: The oxidation reactions were performed at optimum conditions of 3 mL 20% v/v H2SO4, 6.5% w/v ammonium metavanadate, 40 - 60 ºC and 5 min for full colour (blue) development. The proposed method was validated in accordance with International Council...

The present study aimed to develop low-dose liquisolid tablets of two antimalarial drugs artemether-lumefantrine (AL) from nanostructured lipid carrier (NLC) of lumefantrine (LUM), and to estimate the potential of AL as oral delivery system in malariogenic Wistar mice. LUM-NLCs were prepared by hot homogenization using Precirol ATO® 5/Transcutol® H...

New perspectives, new frontiers, new horizons

New perspectives, new frontiers, new horizons

The 24th Annual World Forum on Advanced Materials

Context: Poor aqueous solubility of artemether and lumefantrine makes it important to seek better ways of enhancing their oral delivery and bioavailability. Objective: To formulate and carry out in vitro and anti-malarial pharmacodynamic evaluations of solidified reverse micellar solutions (SRMS)-based solid lipid microparticles (SLMs) of arteme...

The aim of the study was to formulate and evaluate in vitro-in vivo Chloroquine (CQ)-loaded Solid Lipid Microparticles (SLMs). CQ-loaded SLMs were prepared by hot homogenization, lyophilized and characterized using particle size, pH stability, Loading Capacity (LC) and Encapsulation Efficiency (EE). In vitro release of CQ was performed in SIF and S...

The objective of this work was to develop direct compression matrix sustained-release tablets of diphenhydramine HCl and theophylline hydrate using Colocasia antiquorum gum (CAG) extracted by cold maceration as binder. Phytochemical characteristics of the gum were evaluated and different ratios of CAG were applied in the formulations. The physical...

Treatments of bacterial infections have become a difficult task in the medical practice due to high level of resistance to the existing marketed antibiotics. This problem evoked us to search for new antimicrobial agent for better management of bacterial infections. The present study was carried out to evaluate antimicrobial properties of epidermal...

Abstract Context: Formulation, characterization, in vitro and in vivo evaluation of halofantrine-loaded solid lipid microparticles (SLMs). Objective: The objective of the study was to formulate and evaluate halofantrine-loaded SLMs. Materials and methods: Formulations of halofantrine-loaded SLMs were prepared by hot homogenization and thereafter ly...

Objectives: To formulate and evaluate artesunate-loaded lipospheres and study the in vitro-in vivo correlations (IV-IVC). Materials and methods: Lipospheres were formulated by melt homogenisation using structured lipid matrices consisting of (1:3 and 1:6) soybean oil and dika wax and were characterised in vitro and in vivo. Results: The small...

The objective of this study was to evaluate, spectrophotometrically, the compatibility of non-mucinated polyethylene glycol (PEG) 4000 and non-PEGylated mucin in a PEGylated mucin matrices for drug delivery application. Mucin was extracted from the giant African land snails (Archachatina maginata) using chilled acetone and characterized in terms of...

Abstract To develop a novel PEGylated ibuprofen tablet formulations and evaluate its anti-inflammatory activity and pharmacokinetics profile in an animal model. Six batches of PEGylated ibuprofen tablets were prepared by direct compression using Avicel® and lactose as the binder diluents. In vivo anti-inflammatory activity of the tablets was carrie...

The aim of the research was to study the stability, release profile, pharmacokinetic and biodistribution properties of zidovudine (AZT)-solidified reverse micellar microparticulate. Lipid matrices formulated with Phospholipon® 90H and goat fat at ratios of 1:1, 2:1, 3:1 and 2:3 were used to prepare AZT-loaded SLM by melt dispersion followed by lyop...

Abstract Topical administration of gentamicin, a hydrophilic aminoglycoside antibiotic, is limited by membrane impermeability and toxicity concerns. The purpose of this study was to develop and evaluate the antimicrobial activities of an alternative non-invasive, convenient and cost-effective transdermal drug delivery system (TDDS) containing gent...

Various morphological parts of the tropical plant, Clausena anisata (Wild) Hook [family: Rutaceae], have ethnomedical claim for use in the management of epilepsy. This study examined the antiepileptic activity of Clausena anisata root bark, stem bark and leaf ethanolic extracts (i.e. CARE, CASE and CALE respectively) against pentylenetetrazole (PTZ...

Solidified reverse micellar solution (SRMS) were prepared by fusion using 1:1, 2:1 and 1:2 %w/w of Phospholipon ® 90H and Softisan ® 154. Indomethacin (1 %, 3 % and 5 %w/w) were incorporated into the SRMS. SLMs were formulated using the SRMS by melt homogenization techniques using Ultra-Turrax homogenizer; the SLMs were lyophilized to obtain a wate...

To formulate and evaluate solid-reversed-micellar-solution (SRMS)-based solid lipid microparticles (SLMs) for intramuscular administration of gentamicin. SRMS formulated with Phospholipon® 90G and Softisan® 154 were used to prepare gentamicin-loaded SLMs. Characterizations based on size and morphology, stability and encapsulation efficiency (EE%) w...

The objectives of this research were to formulate and evaluate solidified reverse micellar solution (SRMS)-based tablets for oral administration of gentamicin. SRMS matrices formulated with Phospholipon® 90G and Softisan® 154 at ratios 1:1, 1:2 and 2:1 were used to prepare gentamicin tablets by meltsolidification. Characterization based on surface...

The use of traditional medicines and phytopharmaceuticals for treating various ailments dates back several centuries. The aim of the present review is based on relevant data on the different approaches to formulation of various natural compounds from ethnomedicinal plants. Attempts are also being made to enumerate the possible leads from traditiona...