Papers by Keyword: PLGA

Abstract: The coaxial electrospun fibers with large specific surface area, high porosity and core-shell structure have been great applied in biomedical field, especially as drug delivery carriers. In this paper, PLGA(polylactic acid/glycolic acid copolymer) was used as the core and the mixture of PLGA and gelatin was used as the shell. PLGA/gelatin fiber was prepared by coaxial electrospinning technology. The effects of different parameters on the surface morphology and the diameter of fibers were investigated.

Abstract: Ischemic stroke is a common disease in neurology, which seriously affects people's normal work and quality of life and brings a heavy social burden. The nanoparticle carrier generally consists of natural polymer material or synthetic polymer material. Among the synthetic polymer materials, PLGA is one of the most popular carrier materials in recent years. This paper introduces the application of PLGA nanomaterials in ischemic stroke, and reviews the application of PLGA nanomaterials in the diagnosis and tissue repair of ischemic stroke, and drug delivery of neuroprotective drugs. It provides a theoretical basis for the research progress of PLGA nanotechnology in the treatment of anti-stroke and the development of anti-stroke drugs.

Abstract: Exploration of natural compound for the treatment of dental-related problems are gaining of interest for enhancing therapeutic efficacy of the drugs delivery system. In this study, we have prepared terpenoid, which have been isolated from Myrmecodia pendens Merr & Perry from Papua Island, Indonesia, to be encapsulated in Polylactic-co-glycolic acid (PLGA), as the most widely used biodegradable polymer for biomedical applications, through one step single-emulsion method followed by subsequent coating by poly (vinyl alcohol) (PVA). The resultant of terpenoid-loaded PLGA microparticles were characterized systematically through scanning electron microscope and Fourier-transform infrared spectroscopy. In vitro drug release test was evaluated through dialysis method. Antibacterial test was conducted against Enterococcus faecalis as a model for persistent bacteria that causes root canal infections. The results showed that terpenoid-loaded PLGA microparticles were developed in spherical morphology with an average particle size of around 1-2μm. Terpenoid released from PLGA compartment at pH 6.5 and temperature of 37°C through a controlled-release profile mechanism with enhanced prolonged release. The bacterial assay result showed that terpenoid-loaded PLGA microparticles could reduce Enterococcus faecalis, effectively. Eventually, these result show that terpenoid-loaded PLGA microparticles as unique natural product-based extract could be developed as a potential naturally-based drug for dental-related diseases applications.

Abstract: The bone remodeling process plays an essential part of the calcium homeostatic system and provides a crucial mechanism for adaptation to physical stress, the repair of damaged bone and the removal of old bone. We reported previously that sustainable release of simvastatin (SIM) from poly (lactic-co-glycolic acid) (PLGA) formulations could induce bone formation. The aim of this study was to develop a simvastatin-releasing PLGA/β-TCP composite microspheres (β-SPMs) sintered scaffolds (β-SPMSS) as a synthetic bone substitute, and investigate the influence of the dissolution medium on the drug release capabilities of these device based on a physicochemical model for bone remodeling. X-ray diffraction analysis (XRD) results showed β-TCP and SIM could be encapsulated into the PLGA microspheres. The β-SPMs and the β-SPMSS were able to produce sustained release of SIM for 1 month in simulated body fluid (SBF), whereas these composites released SIM for 10 days in acetate buffer (AB). The release rate of SIM from β-SPMSS in AB was faster than in SBF, indicating that the β-SPMSS could control drug release with bone cells activity response, and could be used as a scaffold in bone remodeling area. These results suggested that the β-SPMSS could release SIM sustainably, with bone cells activity response, and could be used as a scaffold in bone remodeling area.

Abstract: The prevalence rate of surgical wound infections caused by bacteria is an average of 9% of the 1.4 million patients worldwide. For this reason, a modification of an absorbable surgical suture coated with extract of Jatropha curcas L. leaves to kill and inhibit the growth of microorganisms needs to be made. The forming of multifilament fibers is done by electrospinning method. The test results of the functional groups showed the presence of interaction between PLGA-Collagen with the extract of Jatropha Curcas L. leaves indicated by an absorption band at 2924 cm^-1 which showed the vibrations of C-H. The tensile test results showed that all samples were in the range of 19.5-87.1 MPa values which corresponded with the modulus of elasticity of the suture thread in the forehead and elbows. The MTT Assay results showed that the percentage of living cells of all samples was above 50%. The bacterial activity test showed that the inhibition zone were in the range of 5-10 mm. The optimal sample showed the degradation rate of 82.2% on the 60th day of the soaking period. It can be concluded that PLGA-collagen Jatropha curcas L. extracts is safe composite and has potential as antibacterial absorbable surgical sutures.

Abstract: PLGA, poly (lactic-co-glycolic-acid), is a kind of biodegradable functional macromolecular organic compounds. PLGA, certified by the Food and Drug Administration (FDA), possesses desirable features of biocompatibility, nontoxicity and no immune response, and is being widely applied to human clinical medical research. Because of its biodegradability, simple synthetic methods, controllability of degrading rate and desirable plasticity, PLGA was applied in large quantity into the carrier materials which is to control the release in recent years, gradually propelling PLGA microsphere controlled release system to be the most ideal drug-carrier system at present. As the carrier of drug and genes, PLGA is mainly researched on its features as the carrier, synthetic methods, different surface modification methods, and the applications on different drugs, genetic treatments and genetic vaccines.

Abstract: Heart failure is a serious major health problem with high number of mortality per year. Bypass is one of the solutions that has often been taken. Nowadays, synthetic materials have been fabricated from polymers to solve the disadvantages which are provided by autograft, allograft and xenograft. The aim of this research is to make a synthetic vascular graft with great physical strength, high biocompatibility, and good affordability. The method of this research was mixing PLGA and collagen by magnetic stirrer. This composite were shaped by spinneret with water as coagulant. Then it was coated by chitosan with 3 variations of weight (1 %wt, 2 %wt, and 3 %wt) to increase hemo and cytocompatibility, proliferation, and cell attachment in order for the vascular graft candidates to be more biocompatible. Mechanical strength for each variation was 5,306 MPa (chitosan 1 %wt), 3,433 MPa (chitosan 2 %wt) and 3,745 MPa (chitosan 3 %wt). All the tensile values were higher than human vascular tensile strength. Toxicity test showed that the living cells in all variations were more than 60% in number, thus the vascular graft is not toxic.Hemolytic assay showed that the lowest coagulation was provided by sample with 3 %wt chitosan.

Abstract: The present work focuses on the development of biodegradable PLGA nanoparticles (NPs) for controlled release of a breast cancer drug, letrozole. NPs of different drug-polymer ratio formulations (F1, F2, F3, F4) were fabricated using solvent evaporation technique. Physico-chemical characteristics of these NPs were assessed using dynamic light scattering (DLS) spectrophotometer. In-vitro drug release study was carried out over an extended period of 30 days at 37 °C in simulated physiological fluid. To evaluate the release kinetics, data was fitted to different models. NPs with various sizes and size distributions were obtained by altering the drug-polymer ratio. Zeta potential of PLGA and drug loaded NPs were found to be-29.4± 1.3 mV and-21.0±0.6 mV, respectively. The release kinetics of the drug from NPs was in good agreement with Korsmeyer-Peppas model, ensuring controlled release of the drug from the NPs. In-vitro release studies showed high correlation coefficient (R² = 0.90) for formulation F2 and F3 up to 30 days. It is concluded that NPs with F2 and F3 formulations provide a controlled release of the incorporated drug and, therefore, hold promise to be investigated further in detail.

Abstract: To prolong the bioactivity of eprinomectin (EPM), a batch of EPM-loaded PLGA microspheres were fabricated by a solvent evaporation method. The morphology of resultant microspheres was observed with an S-4800-I scanning electron microscope (SEM). The EPM release behaviors were investigated with a dialysis method and fitted with Zero-order, First-order, and Higuchi dynamical models. The optimum formula, C_PVA 2.0 w/v%, stirring rate 1, 200 r/min, C_PLGA 4.0 wt%, and oil/water ratio 1/250, was obtained from single-factor experiments. SEM images suggested that the resultant microspheres were monodispersed spheres with a few micropores on their surfaces. Furthermore, more pores and hollows were observed in the degraded PLGA matrix. EPM-loaded PLGA microspheres showed the maximum release amount in the mixture of alcohol/PBS (4/6, v/v). The release process lasted for 30 d, which increased the bioactivity and insecticidal efficacy of EPM. Besides, microspheres with the diameter of 50 μm showed a better release behavior than those from 100 μm and 150 μm ones. Therefore, such method had a promising application on sustained release of veterinary medicine.

Abstract: Devices used in the field of medical technology require high biocompatibility. Medical devices that are made from stainless steel have good biocompatible properties, but polymer coatings can radically improve it. One of the most important quality of the coating is adhesion, and this was our rationale for developing a polymer adhesion testing protocol. In our research, two biocompatible polymers were compared, polyurethane (PUR) and poly-(DL-lactic-co-glycolic acid) (PDLG). Surface-treated stainless steel sheets were used as carrier for polymer layers. The adhesive properties of different layers were compared. Adhesion of the coatings was characterised by concentration of coating solution and surface roughness of the carriers, and some phenomena were observed.