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The recent developments in nanotechnology have driven researchers towards the application of latex extracts for the green synthesis of silver nanoparticles (AgNPs). In this study, AgNPs were biologically synthesized using latex extracts from Tabernaemontana ventricosa, characterized, and their respective biological activities were assessed. Our results showed prominent silver (Ag) peaks at 410 nm confirmed by UV-vis while the elemental percentage composition (3.89 ± 0.16%) of the AgNPs was verified by EDX. The SEM and HRTEM analysis revealed spherical, ovate, and triangular AgNPs, with diameters ranging from 5.00 nm–17.50 nm; however, larger hydrodynamic diameters were revealed by NTA analysis. The FTIR spectra results displayed several peaks of bending and stretching associated with various functional groups such as alcohols, alkanes, amines, proteins, enzymes, and other biomolecules possibly responsible for the capping, reduction, and functionalization of AgNPs. In addition, the AgNPs showed strong antibacterial activity (diameter of the zone of inhibition) against Escherichia coli (12.67 ± 1.15 mm), Staphylococcus aureus (11.67 ± 0.58 mm), and Pseudomonas aeruginosa (11.33 ± 0.58 mm), with significant cytotoxic activity noted in the HeLa cells (10.52 µg/mL). The study confirmed the successful production of AgNPs and recommends T. ventricosa latex extracts as effective capping agents of nanoparticles (NPs). [ABSTRACT FROM AUTHOR]

Species of Combretum are highly valued in Africa due to the plethora of traditional medicinal uses they may offer and the medicinally important phytometabolites they are known to contain. Traditionally, C. erythrophyllum is used to treat bacterial infections, venereal diseases, abdominal pain, sores, infertility, and labour pains, while displaying, anti-viral, anti-parasitic, cytotoxic, and mutagenic activities. There are numerous published works available on the bioactivity of phytometabolites of the leaf extracts of C. erythrophyllum; however there have been limited or no studies published on the bioactivity of the stembark. Hence, this study aimed to provide a comparative analysis of the biological activity of the leaf and stembark extracts of C. erythrophyllum. The following characters were evaluated through the emanating study: total flavonoid and phenolic content, as well as the antioxidant, cytotoxic, and apoptosis activities of the leaf and stembark extract. Methanolic extracts appeared to have the highest possible antioxidant potential among all of the tested extracts and displayed the lowest IC50 values (leaf 5.29 and stembark 4.29 µg/mL) when evaluated using the DPPH assay, the methanolic extracts appeared to quantify the largest amount of compositional phenolic content (1341.05 ± 4.4 mg/GAE/g). Methanolic extracts were the best performing, with the overall lowest IC50 values when tested against HeLa and HEK293 cells (leaf 54.53 µg/mL and stembark 18.30 µg/mL). A positive correlation between % inhibition and extract concentrations was noted for all of the assays. The extent/level of antioxidant activity was seen to be directly proportional to the flavonoid and phenolic content. Extracts with the highest total phenolic content appeared to display the strongest cytotoxic activity. This study integrated the use of fluorescence microscopy with acridine orange staining in order to accurately determine the viability of cells. A direct correlation was observed between the results obtained from the cytotoxicity and apoptosis assay. It may be concluded that the antioxidant properties, total phenolic, and total flavonoid content were directly proportional to the apoptotic and cytotoxic activity expressed by the tested extracts. Focus should now be placed on isolating phytocompounds of importance from the best performing extracts. The transformation of an isolate into a drug of pharmacological importance has yet to be appraised on a large scale. Therefore, further evaluation of this species and particularly the transformation of the isolates needs to be explored as this species has shown immense medicinal potential. [ABSTRACT FROM AUTHOR]

We report the synthesis, spectroscopic characterization and in vitro cytotoxic evaluation of five ruthenium(III) dithiocarbamate complexes. Spectroscopic data indicated that the Ru(III) complexes were isolated as six-coordinate octahedral complexes in which each ruthenium(III) is coordinated to three molecules of dithiocarbamato anions as bidentate chelating ligands. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was used to evaluate the cytotoxic activity of the ruthenium(III) dithiocarbamate complexes against human embryonic kidney (HEK293) and cervical cancer (HeLa). The Ru(III) complexes showed moderate cytotoxic activity towards HEK293 and HeLa cells, but the activity was a bit higher in HEK293 cells compared with HeLa cells. Tris(piperidinedithiocarbamato)ruthenium(III) (1) showed the highest activity in both cell lines with IC50 values of 6.4 and 30.29 µM for both HEK293 and HeLa cells, respectively. Four of the compounds consist of a phenyl ring and they all show IC50 values above 50 µM. These results proved that the cytotoxic activity of the compounds is influenced by the nature of the ligand coordinated to the ruthenium(III) ion. [ABSTRACT FROM AUTHOR]

Nanotechnology is a favorable avenue for improving therapeutic strategies, especially in cancer therapy. The harmful side effects of traditional cancer therapy impact dramatically on the patient's quality of life. Cisplatin, a commonly used anticancer drug, is implicated in side effects such as neurotoxicity, nephrotoxicity and reduced blood cell count. Silver nanoparticles (AgNPs) have been investigated for their antibacterial effects and their anticancer activities to a lesser extent. Their capability as drug delivery vehicles has not been fully exploited, primarily due to their inconclusive cytotoxicity observed in healthy tissues. This study aimed to synthesize and characterize nanoparticles (NPs), consisting of Ag, chitosan (Cs) and folic acid (FA) (CsAg and FACsAg), loading them with cisplatin (C) (C-CsAg and C-FACsAg) and comparing their anticancer activities in the human embryonic kidney (HEK293), breast adenocarcinoma (MCF-7) and cervical carcinoma (HeLa) cells. All NPs and drug nanocomplexes were morphologically and physicochemically characterized, revealing NPs and nanocomplexes of favorable sizes (< 1 1 0 nm), polydispersity and stability. The drug encapsulation efficiencies for C-CsAg and C-FACsAg were 50% and 72%, respectively, while drug release studies indicated that cisplatin release was pH dependent. The C-FACsAg nanocomplexes produced greater anticancer activity than C-CsAg. Folate receptor-mediated uptake was confirmed for the C-FACsAg nanocomplexes in the receptor-rich HeLa cells boding well for future in vivo research. [ABSTRACT FROM AUTHOR]

Chloro, fluoro, and nitro derivatives of 7‐amino‐5‐aryl‐6‐cyano‐5H‐pyrano pyrimidin‐2,4‐diones were produced by reacting malononitrile, barbituric acid, and aromatic aldehydes together with a DABCO catalyst in an aqueous one‐pot reaction. This is the first report of these compounds being synthesized with DABCO as a catalyst, which produced the compounds in yields in excess of 90%. The 2,4‐difluoro derivative (11) was novel. The structures of the synthesized compounds were elucidated by means of 1H, 13C, and 2D NMR spectroscopy. Compound 2 (2‐Cl derivative) had MBC values of <200μM against both Staphylococcus aureus and MRSA, and the 2‐nitro derivative 5 had an MBC of 191μM against the Gram–ve Escherichia coli. The synthesized compounds were also tested for their anticancer activity against a HeLa cell line, where all the compounds showed better activity (IC50 values between 129μM and 340μM) than 5‐fluorouracil, a commonly known anticancer drug. [ABSTRACT FROM AUTHOR]

Delivery of small interfering RNAs (siRNAs) remains a major challenge in their development for therapeutic applications, and cationic liposomes are being actively investigated for this purpose. Six liposome formulations containing the cytofectins 3β[N-(N ′,N ′-dimethylaminopropane)-carbamoyl] cholesterol (Chol-T) or 3β[N-(N ′,N ′,-dimethylaminopropylsuccinamidohydrazido)-carbamoyl] cholesterol (MS09) and varying amounts of distearoylphosphatidylethanolamine poly(ethylene glycol)2000, were prepared. Lipoplexes formed with siRNA were characterized by gel retardation analysis and cryo-electron microscopy. All lipoplexes exhibited low cytotoxicity in the HeLa tat luc cell line while Chol-T lipoplexes, containing anti-luciferase siRNA, achieved 93.4% knockdown of the luciferase transcript at 30 nM siRNA. Poly(ethylene glycol)2000incorporation only marginally reduced knockdown efficiency. [ABSTRACT FROM AUTHOR]

Current chemotherapeutic drugs, although effective, lack cell-specific targeting, instigate adverse side effects in healthy tissue, exhibit unfavourable bio-circulation and can generate drug-resistant cancers. The synergistic use of nanotechnology and gene therapy, using nanoparticles (NPs) for therapeutic gene delivery to cancer cells is hereby proposed. This includes the benefit of cell-specific targeting and exploitation of receptors overexpressed in specific cancer types. The aim of this study was to formulate dendrimer-functionalized selenium nanoparticles (PAMAM-SeNPs) containing the targeting moiety, folic acid (FA), for delivery of pCMV-Luc-DNA (pDNA) in vitro. These NPs and their gene-loaded nanocomplexes were physicochemically and morphologically characterized. Nucleic acid-binding, compaction and pDNA protection were assessed, followed by cell-based in vitro cytotoxicity, transgene expression and apoptotic assays. Nanocomplexes possessed favourable sizes (<150 nm) and ζ-potentials (>25 mV), crucial for cellular interaction, and protected the pDNA from degradation in an in vivo simulation. PAMAM-SeNP nanocomplexes exhibited higher cell viability (>85%) compared to selenium-free nanocomplexes (approximately 75%), confirming the important role of selenium in these nanocomplexes. FA-conjugated PAMAM-SeNPs displayed higher overall transgene expression (HeLa cells) compared to their non-targeting counterparts, suggesting enhanced receptor-mediated cellular uptake. Overall, our results bode well for the use of these nano-delivery vehicles in future in vivo studies. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles (MNPs) have been widely investigated as a strategy to improve the delivery efficiency of therapeutic and diagnostic agents. Substituted iron oxides or ferrite nanoparticles (NPs) such as CoFe2O4 represent an interesting and novel class of MNPs, although they are under-researched in the field of biomedicine. In this study, chitosan-functionalized Mg0.5Co0.5Fe2O4 NPs were loaded with the anti-cancer 5-fluorouracil (5-FU) drug to yield CS-Mg0.5Co0.5Fe2O4-5FU. Transmission electron microscopy (TEM), Fourier Transform infra-red (FTIR) spectroscopy and nanoparticle tracking analysis (NTA) were employed to determine the physiochemical properties of the NPs. Physico-chemical characterizations confirmed spherical NPs with particle sizes of approximately 20.39 nm. Improved colloidal stability was observed, as determined by a zeta potential of approximately −20 mV for the drug-loaded CS-Mg0.5Co0.5Fe2O4 NPs. Drug encapsulation efficiencies of >60% were attained, showing a pH-dependent release of 5-FU. Cell viabilities investigated using the 3-[(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] (MTT) and sulforodhamine B (SRB) assays in human embryonic kidney (HEK293), human breast adenocarcinoma (MCF-7) and human cervical cancer (HeLa) cells showed that these drug-loaded NPs exhibited more targeted tumor-specific cytotoxicities compared to free drugs. CS-Mg0.5Co0.5Fe2O4-5-FU NPs displayed significant targeted delivery potential to the investigated cancer cell lines. Conclusively, these results suggest that the CS-Mg0.5Co0.5Fe2O4-5-FU NPs are promising therapeutic delivery systems in anti-cancer treatment. [ABSTRACT FROM AUTHOR]

Unilamellar cationic liposomes containing phosphatidylcholine, L-α-phosphat-idyl-DL-glycerol, cholesterol and N,N-dimethylaminopropylaminyl succinyl cholesterol in lipoplexes with plasmid ptkNEO transfected HeLa cells efficiently in the presence of G418. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles (MNPs) are attractive for biomedical applications, as contrast agents for magnetic resonance imaging, hyperthermia treatments, cell labelling, magneto-targeted therapy and drug delivery. Spinel ferrites represent a class of MNPs with unique optical, electrical and magnetic properties. In this study, we synthesized, characterized and evaluated the cytotoxicity of polymer-coated Mg 0.5 Co 0.5 Fe 2 O 4 MNPs in human embryonic kidney (HEK293) and cervical carcinoma (HeLa) cells, to determine their future potential in drug/gene delivery. Mg 0.5 Co 0.5 Fe 2 O 4 ferrites were synthesized via a glycol-thermal method, and functionalized with chitosan (CS), polyethylene glycol (PEG) and polyvinyl alcohol (PVA). The morphology and structure of all MNPs were characterized using transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), X-ray diffraction (XRD) and Fourier transform infra-red (FTIR) spectroscopy. Magnetic measurements at 14 kOe, confirmed the superparamagnetic nature of all MNPs, while XRD patterns confirmed typical single-phase cubic spinel structures with average crystallite size < 12 nm, which decreased upon coating. TEM and NTA displayed small, spherical particles, with some agglomeration, and improved colloidal stability (zeta potential > − 30 mV). In vitro cytotoxicity using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and sulforhodamine B (SRB) assays, confirmed moderate to low cytotoxicity in the HEK293 cells, with lower cell viability observed in the HeLa cells, supporting their use in biomedical applications. Unlabelled Image • MNPs were successfully functionalized with chitosan, polyethylene glycol and polyvinyl alcohol,respectively. • All MNPs dislayed desirable physico-chemical properties, nano-sizes and good colloidal stabilities. • The MNPs were well tolerated by the cells with cell survival greater than 60%, except for PEG-MNPs in the HeLa cells. [ABSTRACT FROM AUTHOR]

The synthesis of nanoparticles by green methods, utilizing the extracts from plants has become viable alternative routes for nanomaterial synthesis. The method avoids the expensive and toxic materials used during chemical syntheses. The incorporation of plant extracts with favourable biological properties into nanoparticles has beneficial relevance in the biomedical field. In this study, CuO and Au-CuO nanoparticles were synthesized using the aqueous extract of the Stigmaphyllon ovatum plant and characterised. Optical studies produced peaks around 290 and 670 nm in both nanomaterials, and can be attributed to electron transition and the surface plasmon bands of Cu. The spectra of the Au-CuO nanohybrid showed a broad band around 564 nm due to Au doping. Band gap energies of 3.25 and 3.17 eV were obtained for the CuO and Au-CuO nanohybrids, respectively. The photoluminescence spectra at an excitation wavelength of 200 nm gave different peaks with the near band edge at 300 nm. The synthesized nanoparticles were further evaluated as potential anticancer agents in HeLa cells, and exhibited good anticancer potency with Au-CuO having the greatest activity. The IC 50 values for CuO, Au-CuO nanomaterials and the control drug (5-fluorouracil) were 12.3, 112 and 40 μM respectively. Unlabelled Image • Stigmaphyllon ovatum leaf extract is used for the first time to synthesize Au-CuO nanocomposites • The Tauc plots gave direct band gap energies of 3.25 and 3.17 eV for CuO and Au-CuO respectively • An average particle sizes for CuO NPs and Au-CuO NPs are 4.42nm and 6.40 nm respectively. • The Au-CuO nanohybrids produced better anticancer properties than the CuO NPs. [ABSTRACT FROM AUTHOR]

• Synthesis, photocatalytic and cytotoxic activities of ZnS nanoparticles are reported. • XRD patterns shows hexagonal wurtzite phase of ZnS nanoparticles. • The ZnS nanoparticles sizes are in the range 3.23–4.48 nm. • The photocatalytic degradation efficiency of methylene blue varied from 55 to 71% after 3 h. • The ZnS nanoparticles are very potent against MCF-7 and HeLa cancer cells. We report the synthesis, photocatalytic and cytotoxic studies of hexadecylamine capped zinc sulphide (ZnS) nanoparticles. XRD patterns confirmed hexagonal wurtzite phase of ZnS nanoparticles and HRTEM micrograph revealed spherically shaped particles with sizes in the range 2.81–4.48 nm. Energy band gaps of 4.67, 4.68 and 4.71 eV for ZnS 1 , ZnS 2 and ZnS 3 obtained at 30 min, 1 h and 2 h. The photocatalytic degradation of methylene blue by the as-synthesized ZnS nanoparticles showed degradation efficiency of 55.16% for ZnS 1 , 53.58% for ZnS 2 and 71.17% ZnS 3 after 3 h. Anticancer studies of the ZnS nanoparticles showed they exhibited very potent cytotoxicity activity against breast adenocarcinoma and human cervical carcinoma cancer cell lines. [ABSTRACT FROM AUTHOR]