Analysis Of The Synthesis Of Terpolymer PLG)

Synthesis of terpolymer PLGC:
The terpolymer PLGC was synthesized using a reported procedure with a starting monomer ratio of 70:20:10 of L-LA, GL and Ɛ-CL respectively using the catalyst tin(II)2-ethyl hexanoate. The chemical reaction is given in the figure1. The yield % of the synthesized polymer was calculated by the equation:
Yield %= (Weight of synthesized polymer)/(Weight of the monomers taken) ×100
Characterization of synthesized polymer:
Chemical analysis using Fourier transform infrared Spectroscopy:
Fourier transform infrared (FTIR) spectrum of monomers and synthesized PLGC was obtained in the range of 4000-400 cm-1 using at least 40 scans at a resolution of 4 cm-1. The monomer L-lactide and glycolide spectrum was recorded using
The fresh amniotic membranes are procured from placenta of mothers who have been antenatally screened for the possibility of blood-borne diseases such as HIV, HBsAg, HCV, syphilis, gonorrhoea, toxoplasmosis and cytomegalovirus. Membranes from placenta with trapartum complications are discarded. Processing of amnion involves washing the membrane in sterile water or normal saline, removing the chorionic surface using a sterile gauze, shaking the amniotic membrane in a conical flask with normal saline (0.9%) for 30 min, loading the membrane in rings, drying in laminar air flow for 60 min, freezing in vacuum deep freezer at -30⁰ C for 30 min, packing and sterilization by gamma irradiation at 9.5 kilogray (Kerala agricultural university, Mannuthy,Thrissur). Figure 2 shows lyophilized amniotic
Initially, SNP-PLGC scaffold and amniotic membrane were cut in exact dimensions and the SNP-PLGC scaffold surfaces were saturated with thrombin solution (30 IU/ml) in sterile water for 10 minutes. Then the scaffold were taken out of thrombin and dipped in the fibrinogen (20 mg/ml) solution for ~2 s and kept over the amniotic membrane, then this bi-layered scaffold is allowed to clot for 30 minutes at 37℃ and later deep freezed in -80℃ and lyophilized. Figure 3 illustrates the scheme for designing bilayered scaffold.
Characterization of bilayered scaffold:
Chemical analysis using Fourier transform infrared Spectroscopy:
The bilayered scaffolds was analyzed by ATR method. The samples of 7cm length and 1.5cm width was placed on to the zinc selenide (ZnSe) horizontal flat plate sample holder ATR assembly of a FTIR spectrometer. Background measurements were done without the sample. The spectra were measured between 400 – 4000 cm-1 range with 40 scans per sample at a resolution of 4 cm-1.
Surface topography analysis:
The surface topography of the bilayered scaffolds was analyzed using environmental scanning electron microscope (ESEM, FEI Quanta 200, Netherlands). The scaffolds were fixed on aluminium stubs and the images were acquired at different magnifications. The fiber diameter distribution was quantitatively analyzed from scanning electron micrographs using Image J