Research Publications/Outputs

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Browsing Research Publications/Outputs by browse.metadata.impactarea "Advance Healthcare Materials"

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    Design, In Silico, and In vitro Evaluation of Polymer-Based Drug Conjugates Incorporated with Derivative of Cinnamic Acid, Zidovudine, and 4-Aminosalicylic Acid against Pseudo-HIV-1
    (2024-09) Naki, T; Matshe, William M; Obisesan, O; Balogun, Mohammed O; Oselusi , O; Ray, Suprakas S; Aderibigbe, BA
    Background: The incorporation of anti-HIV drugs into polymer to form polymer-drug conjugates has been reported to result in improved therapeutic activity. Zidovudine, an anti-HIV drug, was explored alone and in combination with known drug molecules using polyamidoaminebased carriers. Objective: Polymer-drug conjugates incorporated with zidovudine, cinnamic acid, and 4-aminosalicylic acid were prepared and evaluated for their potential efficacy in vitro against pseudo- HIV-1. Methods: Aqueous Michael addition polymerization reaction was employed to prepare the conjugates. The conjugates were incorporated with zidovudine, cinnamic acid, and 4-aminosalicylic acid. They were characterized by SEM/EDX, XRD, FTIR, NMR, LC-MS, particle size analysis, in vitro analysis, computational studies, and in silico toxicity predictions. Results: The conjugates displayed spherically shaped morphology. The in vitro findings showed that polymer-drug conjugates, T15 and T16, with a single drug were effective against pseudo- HIV-1 at high concentrations of 111.11 and 333.33 μg/mL, respectively. Molecular docking studies supported the in vitro results. Additionally, SwissADME, ProTox-II, and GUSAR (General Unrestricted Structure-Activity Relationships) analyses revealed that these compounds have promising antiviral potential. Conclusion: The prepared polymer-drug conjugates with a single drug showed promising effects against the Pseudo-HIV-1, and the conjugates displayed features that make them potential anti- HIV therapeutics that require further studies.
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    Dual antimicrobial activity of HTCC and its nanoparticles: A synergistic approach for antibacterial and antiviral applications through combined in silico and In vitro studies
    (2024-10) Dhlamini, Khanyisile S; Selepe, Cyril T; Ramalapa, Bathabile E; Cele, Zamani E; Malatji, Kanyane; Govender, Krishna K; Tshweu, Lesego L; Ray, Suprakas S
    N-(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (HTCC), a quaternized chitosan derivative, has been shown to exhibit a broad spectrum of antimicrobial activity, especially against bacteria and enveloped viruses. Despite this, molecular docking studies showing its atomic-level mechanisms against these microorganisms are scarce. Here, for the first time, we employed molecular docking analyses to investigate the potential antibacterial activity of HTCC against Staphylococcus aureus and its antiviral activity against human immunodeficiency virus 1 (HIV-1). According to the findings, HTCC exhibited promising antibacterial activity with high binding affinities; however, it had limited antiviral activity. To validate these theoretical outcomes, experimental studies were conducted. Different derivatives of HTCC were synthesized and characterized using NMR, XRD, FTIR, and DLS. The in vitro assays validated the potent antibacterial efficacy of HTCC against S. aureus, whereas the antiviral studies did not show good antiviral activity. However, our research also revealed a promising avenue for further exploration of the antimicrobial activity of HTCC nanoparticles (NPs), since, thus far, no studies have been conducted to show the antiviral activity of HTCC NPs against HIV-1. The nanosized HTCC exhibited superior antiviral performance compared to the parent polymers, with complete (100%) inhibition of HIV-1 viral activity at the highest tested concentration (0.33 mg/mL).
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    In vitro antiplasmodium and antitrypanosomal activities, β-haematin formation inhibition, molecular docking and DFT computational studies of quinoline-urea-benzothiazole hybrids
    (2024-10) Oyeneyin, OE; Moodley, R; Mashaba, C; Garnie, LF; Omoboyowa, DA; Rakodi, GH; Maphoru, MV; Balogun, Mohammed O; Hoppe, H; Egan, TJ; Tukulula, M
    Quinoline-urea-benzothiazole hybrids exhibited low to sub-micromolar in vitro activities against the Plasmodium falciparum (P. falciparum) 3D7 chloroquine (CQ)-sensitive strain, with compounds 5a, 5b and 5f showing activities ranging from 0.33 to 0.97 μM. Against the formation of β-haematin, the majority of the tested compounds were comparable to the reference drug, chloroquine (CQ), with compounds 5c (IC50 = 9.55 ± 0.62 μM) and 5h (IC50 = 9.73 ± 1.38 μM), exhibiting slightly better in vitro efficacy than CQ. The hybrids also exhibited low micromolar to submicromolar activities against Trypanosoma brucei brucei, with 5j-5k being comparable to the reference drug, pentamidine. Compound 5b displayed higher in silico binding energy than CQ when docked against P. falciparum dihydroorotate dehydrogenase enzyme. Compounds 5j and 5k showed higher binding energies than pentamidine within the trypanothione reductase enzyme binding pocket. The root means square deviations of the hit compounds 5b, 5j and 5k were stable throughout the 100 ns simulation period. Post-molecular dynamics MMGBSA binding free energies showed that the selected hybrids bind spontaneously to the respective enzymes. The DFT investigation revealed that the compounds have regions that can bind to the electropositive and electronegative sites of the proteins.
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    Removal of Tobacco Specific Carcinogenic Nitrosamines in Mainstream Cigarette Smoke and Aqueous Solution─A Review
    (2025-05) Setshedi, Katlego Z; Maity, Arjun A; Nyakale, Atlegang K; Ramahlare, Sebasa T; Chauke, Vongani P; Nkomzwayo, Thulisile N; Mandiwana, Vusani; Ray, Suprakas S; Hlekelele, Lerato
    Tobacco-specific N-nitrosamines (TSNAs), which are associated with several cancers, are formed during the processing of tobacco alkaloids. Since tobacco smoking poses serious health risks, scientists, governments, and health regulators globally have denounced it and categorized its constituents according to their carcinogenicity. Tobacco smoke investigations are guided by standardized methods (ISO). With the help of standardized smoke-generating machines, precise quantification of TSNAs and other smoke constituents is now possible thanks to advancements in analytical techniques. This information supports initiatives to reduce the amount of TSNAs that smoking exposes people to. This review covers the occurrence, formation pathways, precursors, and control strategies through removal technologies, providing thorough analysis of the state of science today regarding TSNAs. The adsorption characteristics of different materials as possible filter additives or modifiers are critically discussed, emphasizing important elements like porosity, layering, acidity/alkalinity, and surface area that affect their performance for capturing TSNAs from smoke. While scientific understanding of these areas is still evolving, this review intends to provide for the first time research progress on the adsorption properties of various materials, including zeolites, silica, few-layer black phosphorus, metal–organic frameworks, and molecularly imprinted polymers, among others, for reducing TSNAs present in both cigarette smoke and aqueous solutions.
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    Synthesis, characterization and antiviral efficacy of valacyclovir loaded polymeric nanoparticles against wild-type herpes simplex virus type 2
    (2025-06) Obisesan, OS; Tshweu, Lesego L; Nkabinde-Thete, Lindiwe; Ramalapa, Bathabile , OS Tshweu; Ngoepe, MP; Saartjie, R; Mufhandu, HT
    Herpes simplex virus type 2 (HSV-2) remains a significant public health concern due to its high rates of mortality and morbidity. While various chemotherapeutic options exist for treating HSV-2, they are often inadequate as none provide a definitive cure, and there is a growing issue of drug-resistant strains. The introduction of nanomedicine for antiviral drug delivery offers a promising avenue to enhance the effectiveness of these treatments. This study explored an innovative approach to treating HSV-2 by encapsulating valacyclovir in biodegradable polycaprolactone (PCL) using a double emulsion technique. The formulated valacyclovir-loaded polymeric nanoparticles were characterized, revealing monodispersed particles with an average hydrodynamic size ranging from 154.9 ± 2.1 to 232.8 ± 6.2 nm, along with an encapsulation efficiency of 50%–66% and a drug loading capacity of 11.6%–13.9%. Additionally, there is no significant cytotoxicity of the test compounds to Vero cells at 0.3 mg ml−1 concentration with a cell viability within the range of 85 ± 13.6%−100 ± 4.8%. The antiviral activity of both the free drug (valacyclovir) and the valacyclovir-loaded polymeric nanoparticles was assessed in HSV-2 infected Vero cells. The results demonstrated that the valacyclovir-loaded nanoparticles exhibited a 1.2–1.3fold (p < 0.005) increase in antiviral efficacy compared to the free drug. This study thus presents a novel nanotechnology-based treatment approach for HSV-2, offering enhanced antiviral effectiveness over traditional treatments.