Molecular characterization of selected nasal isolates of methicillin-resistant Staphylococcus aureus (MRSA) from healthy students of a tertiary institution

Purpose: To investigate the incidence of methicillin-resistant Staphylococcus aureus (MRSA) and carry out molecular characterization in selected nasal isolates from healthy students in Abraka, Nigeria.Methods: Three hundred (300) samples were obtained from apparently healthy 150 female and 150 male students and were cultured in suitable media for identification. The MRSA were detected by means of oxacillin antibiotic sensitivity disk. Antibiotics susceptibility pattern of MRSA isolates was carried out in accordance with the guidelines of Clinical Laboratory Standard Institute. Tests were carried out to determine the presence of penicillin binding protein2a (PBP2a). Molecular characterization of twenty (20) MRSA representatives was done to establish the existence of the mecA genes among the isolates.Results: The incidence of MRSA colonization amongst apparently healthy students in the community was 68 (22.7 %). The sensitivity pattern was: amoxicillin, 40 (58.8 %); amoxicillin/clavulanate, 15 (22.1 %); chloramphenicol, 15 (22.1 %); ciprofloxacin, 19 (27.9 %); co-trimoxazole, 9 (13.2 %); gentamicin, 9 (13.2 %); ofloxacin, 8 (11.1 %); and streptomycin, 30 (44.1 %). All the twenty (20) isolates subjected to molecular characterization possessed penicillin binding protein2a (PBP2a) while only one possessed the mecA gene.Conclusion: The MRSA is present among healthy individuals in Abraka, Delta State. It is also possible not to detect the existence of the mecA gene even when penicillin binding protein2a is present. Since most of the MRSA isolates are multi-drug resistant, there is a tendency for clinical antibiotic therapy failure in this area

Preliminary spectroscopic characterization of PEGylated mucin, a novel polymeric drug delivery system

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 qualitative properties and solubility profile. Polymeric matrices composed of PEG 4000 and mucin in ratios of 2:0 (A), 1:1 (B), 2:1(C) and 3:1 (D) were prepared by co-precipitation using chilled acetone. The matrices were characterized with respect to compatibility using the Fourier transform infrared (FT-IR) spectroscopy. Results of the qualitative tests performed on the snail mucin showed that carbohydrates, proteins and trace amounts of fats were present; the extracted mucin was light-brownish in colour, with a pleasant meaty odour. Snail mucin, when dispersed in water yielded a slightly viscous dispersion, but is not soluble in ethanol, acetone, 0.1 M sodium hydroxide, ammonium hydroxide and sulphuric acid. The presence of different peaks in the FT-IR spectra of the PEGylated mucin matrices compared with the non-PEGylated mucin (2:0) matrix and non-mucinated PEG 4000 (0:2) matrix indicated the formation of new polymers, which could be employed in drug delivery. This study has shown that PEGylation of mucin gives rise to new polymeric system with principal FT-IR peaks quite different from those of non-PEGylated mucin and nonmucinated PEG, and this may be employed in the delivery of drugs.Key words: PEGylation, drug delivery, mucin, Fourier transform infrared (FT-IR) spectroscopy, Archachatina maginata

Novel Intravaginal Drug Delivery System Based on Molecularly PEGylated Lipid Matrices for Improved Antifungal Activity of Miconazole Nitrate

The aim of this study was to investigate the potential of microparticles based on biocompatible phytolipids [Softisan® 154 (SF) (hydrogenated palm oil) and super-refined sunseed oil (SO)] and polyethylene glycol- (PEG-) 4000 to improve intravaginal delivery of miconazole nitrate (MN) for effective treatment of vulvovaginal candidiasis (VVC). Lipid matrices (LMs) consisting of rational blends of SF and SO with or without PEG-4000 were prepared by fusion and characterized and employed to formulate MN-loaded solid lipid microparticles (SLMs) by melt-homogenization. The SLMs were characterized for physicochemical properties, anticandidal activity, and stability. Spherical discrete microparticles with good physicochemical properties and mean diameters suitable for vaginal drug delivery were obtained. Formulations based on SO:SF (1:9) and containing highest concentrations of PEG-4000 (4 %w/w) and MN (3.0 %w/w) were stable and gave highest encapsulation efficiency (83.05–87.75%) and inhibition zone diameter (25.87±0.94–26.33±0.94 mm) and significantly (p<0.05) faster and more powerful fungicidal activity regarding killing rate constant values (7.10 x 10−3–1.09 x 10−2 min−1) than commercial topical solution of MN (Fungusol®) (8.00 x 10−3 min−1) and pure MN sample (5.160 x 10−3 min−1). This study has shown that MN-loaded SLMs based on molecularly PEGylated lipid matrices could provide a better option to deal with VVC