Green Electrospining of Hydroxypropyl Cellulose Nanofibres for Drug Delivery Applications

Electrospun nanofibers mats are green synthesized using hydroxypropyl cellulose (HPC) individually or in conjugation with either poly(vinyl alcohol) (PVA) or Polyvinylpyrrolidone (PVP) to enhance the mechanical properties of the nanofibers mats. Desirable attributes of the as-obtained nanofibers mats are manifested via using SEM, FT-IR, TGA and conventional tools for mechanical and physical properties. The obtained data from SEM images demonstrated that the diclofenac sodium (DS) loaded nanofibers mats did not provide significant change of the morphological structure to the mats. In addition the thermal stability and the visual and mechanical properties of PVA or PVP was dramatically enhanced with the addition of HPC. The in vitro sustained release of DS drug was controlled when loaded into electrospun nanofibers of HPC with either PVA or PVP.

Synthesis of new morpholine-connected pyrazolidine derivatives and their antimicrobial, antioxidant, and cytotoxic activities

A simple and convenient one-pot four-component synthesis of morpholine-connected pyrazolidine derivatives 2a-f and 4a-f was developed using direct metal-free catalysis, with the identities of the synthesized compounds confirmed by IR, NMR (¹H and ¹³C), mass spectrometry, and elemental analysis. The prepared compounds were inspected for antimicrobial, antioxidant, and cytotoxic activities. Antimicrobial and antifungal activities against five bacterial and four fungal pathogens, respectively, were investigated using the disc diffusion technique. In antibacterial activity, compounds 2d and 2f (MIC=2μg/mL) exhibited significantly higher activity than the standard ciprofloxacin. The results of antifungal assay showed that the activity of compound 4a (MIC=0.5μg/mL) was significantly higher than the standard clotrimazole. Antioxidant activity was screened based on ABTS⁺ radical scavenging and linoleic acid peroxidation performance. Compound 4a showed substantial antioxidant (91.3%) activities, as compared with the Trolox standard. Cytotoxicity was evaluated using HepG2 (liver), HeLa (cervical), and MCF-7 (breast) cancer cell lines, with high toxicities observed for 2b (GI₅₀=12.2μm) and 4a (GI₅₀=07.8μm).

Synthesis and antibacterial of carboxymethyl starch-grafted poly(vinyl imidazole) against some plant pathogens

Poly(N-vinyl imidazole) (PVI) has been grafted onto carboxymethyl starch (CMS) in aqueous solution using potassium persulfate (KPS) as initiator. Reaction parameters that affect grafting efficiency and percentage grafting such as monomer and initiator concentration, the reaction temperature and time were investigated. The grafted products were characterized by FTIR, thermal analysis, SEM photograph and elemental analysis. The antibacterial effects of the carboxymethyl starch-grafted-poly(N-vinylimidazole) (CMS-g-PVI) was examined against two plant pathogens Gram negative bacteria: Xanthomonas perforanss and Xanthomonas oryzae. Generally, upon application of the CMS-g-PVI to the bacterial cells; the mortality rate increased from 45.71 to 59.37% for Xanthomonas perforans and X. oryzae, respectively. While the MIC for most of both bacterial strains were recorded at concentration of 60 μg/mL. The results indicate that CMS-g-PVI has bactericidal properties and can be used for seed treatment to control xanthomonads associated with bacterial leaf spot (BLS).