This paper presents the anomalous release kinetics of a cancer drug (prodigiosin) frompoly-n-isopropyl-acrylamide ( P(NIPA))-based gels. The release exponents, n, which correspond to the drug release mechanisms, were found to be between 0.41 and 1.40. This is within a range that include Fickian case I (n = 0.45) and non-Fickian diffusion (case II) (n > 0.45) for cylindrical drug-loaded structures. The results, however, suggest that the release exponents, n, correspond mostly to anomalous case II and super case II transport mechanics with sigmoidal characteristics. The drug release kinetics of the P(NIPA)-based hydrogels are well described by bi-dose functions. The observed drug release behavour is related to the porosity of the hydrogels, which can be controlled by cross-linking and copolymerization with acrylamide, which also improves the hydrophilicity of the gels. The paper also presents the effects of cancer drug release on cell survival (%), as well as the cell metabolic activities of treated cells and non-treated cells. The implications of the results are discussed for the development of implantable thermosensitive gels for the controlled release of drugs for localized cancer treatment.

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This paper presents in vitro studies of the sustained release of Annona muricata leaf extracts (AME) from hybrid electrospun fibers for breast cancer treatment.Electrospun hybrid scaffolds were fabricated from crude AME extracts, poly(lacticco-glycolic acid)/gelatin (PLGA/Ge) and pluronic F127. The physicochemical properties of the AME extract and scaffolds were studied. The antiproliferative effects of the scaffolds were also assessed on breast cancer (MCF-7 and MDA-MB-231) and non-tumorigenic breast (MCF10A) cell lines. Scanning electron microscope micrographs revealed a random network of micro-and submicron fibers. In vitro drug release profiles, governed by quasi-Fickian diffusion at pH 7.

Electrospinning technique has emerged as a widespread technology used to produce scaffolds (a synthetic nanofibrous structures) with morphologies and diameters in a range akin to those found in the Extra Cellular matrices (ECMs) of human tissues. Nanofibres were produced from a blend of two optical isomers of poly(Lactic acid): the Crystalline poly(D, lactic acid) (PDLA) and the hemicrystalline poly(L, lactic acid) (PLLA), at different electrospinning parameters. This was carried out in quick succession by sandwiching PLLA between PDLA. The resultant scaffold with fibre diameter 770 nm was successfully obtained at voltages of 15 kV and 18 kV for the PDLA and PLLA respectively, on a rotating mandrel collector. The SEM images show good fibres alignment and the average tensile modulus of the scaffold was approximately 176 MPa. This result reveals that the sandwiched scaffold is tough and ductile and would successfully enhance neogenesis. The scaffold, therefore, would support the mechanical strength of tissues with high mechanical demand, such as heart valves, tendon or ligament. Thus, the scaffold could be suitable for application in various tissue engineering and implants technology.