Admire Dube

University of the Western Cape | uwc · School of Pharmacy

Globally a significant burden of tuberculosis (TB) is faced, which is difficult to eradicate due to patients' non‐adherence, and drug‐resistant strains that are spreading at an alarming rate. Novel approaches are required to improve diagnosis and treatment. Metallic nanoparticles (MNPs) have demonstrated potential as sensor probes and in combinatio...

Despite multiple treatments for tuberculosis (TB), there are ≈10 million new cases and 1.5 million deaths annually, warranting the need for new therapeutics. Major clinical treatment issues include the length of treatment which is associated with patient non‐compliance; and poor cellular drug penetration leading to the generation of drug‐resistant...

Having a robust, integrated regulatory system is important for ensuring the availability of safe and efficacious medical products of good quality and for protecting public health. However, less than 30% of countries globally have reached the required regulatory maturity level three, with low- and middle-income countries facing challenges in attract...

The disruption of periodontal biofilms and prevailing antimicrobial resistance issues continue to pose a great challenge to the treatment of periodontitis. Here, we report on selenium nanoparticles (SeNPs) as a treatment alternative for periodontitis by determining their antibiofilm activity against S. mutans biofilms and the potential role of part...

The vision of the African Medicines Agency (AMA) is to ensure that all Africans have access to affordable medical products that meet internationally recognised standards of quality, safety and efficacy for priority diseases/conditions. The AMA is being established by a treaty which had to be ratified by a minimum of 15 African countries. Although t...

This study reports the effects of a computationally informed and avocado-seed mediated Phyto engineered CuS nanoparticles as fertilizing agent on the ionome and amino acid metabolome of Pinto bean seeds using both bench top and ion beam analytical techniques. Physico-chemical analysis of the Phyto engineered nanoparticles with scanning-electron mic...

Phytochemicals are promising therapeutics for various neurodegenerative disorders, including Parkinson’s disease (PD). However, their efficacy, pharmacokinetic properties, and penetration across the blood–brain barrier can be improved using delivery systems such as nanoparticles. We reviewed recently published work in which nanoparticles were used...

The aim was to assess the suitability of three nano-based transdermal drug delivery systems containing ibuprofen: a nano-emulsion, a nano-emulgel, and a colloidal suspension with ibuprofen-loaded nanoparticles. Understanding the transdermal delivery of ibuprofen using nano-based drug delivery systems can lead to more effective pain relief and impro...

The application of nanotechnology in antimicrobial and cytotoxicity studies has recently been receiving increased interest. This paper report on the use of Persea americana Mill. (avocado) seed husk to synthesize hydronium jarosite nanoparticles in a facile, economical, and eco-friendly manner. We describe firstly the synthesis of hydronium jarosit...

Waterborne disease is a global health threat contributing to a high burden of diarrhoeal disease, and growing evidence indicates a prospective increase in incidence coinciding with the profound effects of climate change. A major causative agent of gastrointestinal disease is Cryptosporidium, a protozoan waterborne parasite identified in over 70 cou...

Background Medical products incorporating nanoparticle drug delivery systems (nanomedicines) are therapeutic or imaging agents, which comprise a delivery system within the nanometer size range (1 – 1000 nm). As medical products, nanomedicines meet definitions of medicines according to various national legislations for regulation of medicines. Howev...

In the present study, a chitosan (CS)-coated liposome (LipCsP-Chitosan) nanocarrier was fabricated for the delivery of Carissa spinarum (CsP) polyphenols to improve bioavailability and anti-pneumococcal potential against Klebsiella pneumoniae. LipCsP-Chitosan was synthesized by the ion gelation method and characterized by using a Malvern zetasizer...

IntroductionIn 2016, the African Union (AU) Model Law on Medical Products Regulation was endorsed by AU Heads of State and Government. The aims of the legislation include harmonisation of regulatory systems, increasing collaboration across countries, and providing a conducive regulatory environment for medical product/health technology development...

Transdermal delivery of active pharmaceutical ingredients (APIs) can be challenging, since the skin possesses a rate-limiting barrier, which may be overcome when APIs possess certain ideal physicochemical properties. The lack thereof would require that APIs be included in drug delivery vehicles to enhance skin permeation. Hence, diclofenac was inco...

Introduction The presence of N-nitrosamine impurities in medicines raised concerns globally as they are genotoxic and probable human carcinogens. A review of N-nitrosamine impurities in medicines provides an opportunity for National Regulatory Authorities (NRAs) to ensure that corrective and preventive actions are applied so that safe and good qual...

Along with the increasing requirement for efficient organic conversions using green chemistry, there is a need to develop highly efficient and eco-friendly catalytic reaction systems. Gold nanoparticles (AuNPs)-based nanocatalysts are promising candidates for the reduction of environmental pollutants, such as nitroaromatics and dyes. This study rep...

Diclofenac (2-[(2,6-dichlorophenyl)amino]phenyl]acetic acid) was incorporated into different drug delivery vehicles to investigate the transdermal delivery thereof. These drug delivery vehicles included nano-emulsions, nano-emulgels and a colloidal suspension containing drug-loaded nanoparticles. The formulation of nano-emulsions and nano-emulgels...

Since the discovery of Mycobacterium tuberculosis (Mtb), the bacteria that causes tuberculosis (TB), in the 1880s, TB has been a global pandemic; and it is one of the deadliest infectious diseases after covid-19. To date, TB has claimed the lives of over 1 billion people. With an estimated 10.4 million new cases and 1.7 million fatalities each year...

Tuberculosis (TB) and human immunodeficiency virus (HIV) represent a significant burden of disease on a global scale. Despite improvements in the global epidemic status, largely facilitated by increased access to pharmacotherapeutic interventions, slow progress in the development of new clinical interventions coupled with growing antimicrobial resi...

The medicines regulatory landscape in Africa is undergoing transformation with at least two countries having National Medicines Regulatory Authorities (NRAs) that operate at World Health Organization (WHO) maturity level 3. However, this represents the exception as over 90% of African NRAs have limited capacity to perform core medicine regulatory f...

Insufficient access to quality, safe, efficacious and affordable medical products in Africa has posed a significant challenge to public health for decades. In part, this is attributed to weak or absent policies and regulatory systems, a lack of competent regulatory professionals in National Medicines Regulatory Authorities (NMRAs) and ineffective r...

Advances in nanotechnology have enabled the development of a new generation of vaccines, which are playing a critical role in the global control of the COVID-19 pandemic and the return to normalcy. Vaccine development has been conducted, by and large, by countries in the global north. South Africa, as a major emerging economy, has made extensive in...

The anatomical structure of the brain at the blood–brain barrier (BBB) creates a limitation for the movement of drugs into the central nervous system (CNS). Drug delivery facilitated by magneto-electric nanoparticles (MENs) is a relatively new non-invasive approach for the delivery of drugs into the CNS. These nanoparticles (NPs) can create localiz...

Nanoparticles (NPs) that can activate macrophages infected with the tuberculosis causative pathogen Mycobacterium tuberculosis, could be an effective host directed therapy for the disease. In this study, curdlan was conjugated to poly(lactic-co-glycolic acid) (PLGA) to produce immunotherapeutic NPs. Various physicochemical characterizations were us...

The risk of secondary bacterial infections resulting from dental procedures has driven the design of antimicrobial and antifouling dental materials to curb pathogenic microbial growth, biofilm formation and subsequent oral and dental diseases. Studies have investigated approaches based primarily on contact-killing or release-killing materials. Thes...

Polysaccharides have received a lot of attention in biomedical research for their high potential as scaffolds owing to their unique biological properties. Fibrillar scaffolds made of chitosan demonstrated high promise in tissue engineering, especially for skin. As far as bone regeneration is concerned, curdlan (1,3-β-glucan) is particularly interes...

The major causative agent of tuberculosis (TB), i.e., Mycobacterium tuberculosis (Mtb), has developed mechanisms to evade host defense responses and persist within host cells for prolonged periods of time. Mtb is also increasingly resistant to existing anti-TB drugs. There is therefore an urgent need to develop new therapeutics for TB and host dire...

A nanoformulation composed of curdlan, a linear polysaccharide of 1,3‐β‐linked d‐glucose units, hydrogen bonded to poly(γ ‐glutamic acid) (PGA), was developed to stimulate macrophage. Curdlan/PGA nanoparticles (C‐NP) are formulated by physically blending curdlan (0.2 mg mL⁻¹ in 0.4 m NaOH) with PGA (0.8 mg mL⁻¹). Forster resonance energy transfer (...

Antibiotic resistance is increasing at such an alarming rate that it is now one of the greatest global health challenges. Undesirable toxic side-effects of the drugs lead to high rates of non-completion of treatment regimens which in turn leads to the development of drug resistance. We report on the development of delivery systems that enable antib...

The use of natural products as chemotherapeutic agents is well established; however, many of these are associated with undesirable side effects, including high toxicity and instability. Furthermore, the development of drug resistant cancers makes the search for new anticancer lead compounds a priority. In this study, the extraction of an Ircinia sp...

Abstract Obesity through its association with type 2 diabetes (T2D), cancer and cardiovascular diseases (CVDs), poses a serious health threat, as these diseases contribute to high mortality rates. Pharmacotherapy alone or in combination with either lifestyle modification or surgery, is reliable in maintaining a healthy body weight, and preventing p...

Objective: To evaluate the impact of PEG content on poly(lactic-co-glycolic acid) (PLGA) NP physicochemical properties, hydrophobic drug release (rifampicin as a model drug) and human serum protein binding. Methods: Rifampicin loaded and unloaded nanoparticles with PEG content of 0-17% (w/w) were prepared by an emulsification-evaporation techniq...

Nanoparticles (NPs) have gained importance in addressing drug delivery challenges across biological barriers. Here, we reformulated pentamidine, a drug used to treat Human African Trypanosomiasis (HAT) in polymer based nanoparticles and liposomes and compared their capability to enhance pentamidine penetration across blood brain barrier (BBB). Size...

Purpose Salinomycin (SAL) is a polyether compound that exhibits strong antimicrobial as well as anticancer activity. Nanomedicine has been at the forefront of drug delivery research with the aim of increasing the efficacy, specificity and reduce toxicity of drugs. There is an intersection between infection and cancer, and cancer patients are prone...

South Africa has the world's largest antiretroviral (ARV) program and despite having stringent upstream medicine's regulatory oversight, the post-market reassessment of ARV quality is prohibitively resource intensive. The aim of this study was to evaluate and compare the post-market quality of four fixed-dose combination (FDC) generics containing e...

Low-and-middle-income countries (LMICs) have high disease burdens, necessitating increased research. However, LMIC research output constitutes only 2% of global total. To increase output, researchers must be capacitated. The University of Zimbabwe (UZ) and the University at Buffalo (UB), developed and implemented the AIDS International Research Tra...

Tuberculosis (TB) caused by Mycobacterium tuberculosis remains a deadly infectious disease. The thin pipeline of new drugs for TB, the ineffectiveness in adults of the only vaccine available, i.e. the Bacillus Calmette-Guerin vaccine, and increasing global antimicrobial resistance, has reinvigorated interest in immunotherapies. Nanoparticles (NPs)...

Background : The development of appropriate dosage forms for paediatric antiretroviral therapy is key for improved therapeutic outcomes in children. The focus of this study was to improve solubility, dissolution rate, drug release and maintain high drug permeability. Methodology : A nanoemulsion was prepared using emulsion inversion point and evalu...

Purpose: Mycobacterium tuberculosis which causes tuberculosis, is primarily resident within macrophages. 1,3-β-glucan has been proposed as a ligand to target drug loaded nanoparticles (NPs) to macrophages. In this study we characterized the intracellular pharmacokinetics of the anti-tubercular drug rifampicin delivered by 1,3-β-glucan functionaliz...

Nanomedicine is one of the most exciting applications of nanotechnology and promises to address several of mankind’s healthcare needs. South Africa is one of the countries engaged in nanomedicine research and product development on the African continent. In this article, we provide a top-level description of the policy, infrastructure, and human ca...

Infectious diseases including HIV/AIDS and tuberculosis (TB) are a major cause of deaths worldwide. These intracellular pathogens regulate the innate immune response allowing for pathogen survival, persistence and further transmission. Nanoparticles provide an opportunity for the targeted delivery of immune modulating signals to host cells, harness...

Objective: To reduce the amount of the antiretroviral (ARV) nevirapine necessary to achieve therapeutic concentrations using macrophage targeted nanoparticles. Methods: Core-shell nanoparticles were prepared from FDA approved, biodegradable and biocompatible polymers, with poly(lactic-co-glycolic) acid (PLGA) as the core and chitosan (CS) as the...

Nanomedicine is an emerging and rapidly evolving field and includes the use of nanoparticles for diagnosis and therapy of a variety of diseases, as well as in regenerative medicine. In this mini-review, leaders in the field from around the globe provide a personal perspective on the development of nanomedicine. The focus lies on the translation fro...

Pralidoxime is an organophosphate antidote with poor central nervous system distribution due to a high polarity. In the present study, pralidoxime-loaded poly(lactic-co-glycolic acid) nanoparticles were prepared and evaluated as a potential delivery system of the drug into the central nervous system. The nanoparticles were prepared using double emu...

Tafenoquine (TQ), a new synthetic analog of primaquine, has relatively poor bioavailability and associated toxicity in glucose-6-phosphate dehydrogenase (G6PD)-deficient individuals. A microemulsion formulation of TQ (MTQ) with sizes <20 nm improved the solubility of TQ and enhanced the oral bioavailability from 55% to 99% in healthy mice (area und...

There is significant interest in the application of nanoparticles to deliver immunostimulatory signals to cells. We hypothesized that curdlan (immune stimulating polymer) could be conjugated to PLGA and nanoparticles from this copolymer would possess immunostimulatory activity, be non-cytotoxic and function as an effective sustained drug release sy...

Background: Tuberculosis remains one of the greatest health challenges worldwide, hence the need for development of better diagnostic tools and effective treatments. Nanotechnology and particulate drug delivery systems are examples of systems which can enhance drug delivery. Isoniazid is a key pharmaceutical agent in fixed dose combination therapy...

Introduction: Tuberculosis (TB) ranks the second leading cause of death from an infectious disease worldwide. However, treatment of TB is affected by poor patient compliance due to the requirement for daily drug administration, for lengthy periods of time, often with severe drug-induced side effects. Nanomedicines have the potential to improve tre...

The green tea catechin (-)-epigallocatechin gallate (EGCG) has attracted significant research interest due to its beneficial therapeutic effects, which include anti-oxidant, neuro-protective and anti-cancer effects. However, the therapeutic potential of EGCG following oral consumption is limited by its poor absorption. To address this issue, EGCG h...

The plasma exposure of (−)-epigallocatechin gallate (EGCg) is typically assessed following administration of EGCg at doses equivalent to the consumption of at least 10 cups of green tea in one sitting. This study determines the plasma concentrations of EGCg in mice following administration of a dose reflecting typical consumption of one standard gr...

Catechins found in green tea have received considerable attention due to their favourable biological properties which include cardioprotective, neuroprotective and anti-cancer effects. However, their therapeutic potential is limited by their low oral bioavailability, attributed to poor stability and intestinal absorption. We encapsulated (+)-catech...

a b s t r a c t Catechins are an important class of dietary flavonoids with promising use as therapeutic agents due to their potent antioxidant activity and diverse biological properties. However, catechins are highly unstable in alkaline solutions, such as those present in some biological fluids and experimental protocols. In this study, we optimi...

Herbal materials are known to present significant challenges with regard to designing credible placebos. This study intended to demonstrate the possibility of designing placebo material for crude herbals and used Artemisia afra, a popular traditional herbal medicine in South Africa, as a model. To produce the placebo, step-wise solvent extractions...

Artemisia Afra, a popular South African traditional herbal medicine is commonly administered as a tea infusion of the leaves. However, clinical trials proving it safety and efficacy are lacking mainly due to the absence of good quality dosage forms and credible placebos for the plant. The objectives of this study were to prepare a standardized prep...