Polycaprolactone (PCL) is a biocompatible polyester explored in forming various medical devices and tissue regeneration. Further, mechanical properties and non-enzymatic degradation (by hydrolysis) of PCL can be altered by regulating its molecular weight. A novel process of dissolving PCL in 94% acetic acid was explored which spontaneously formed membranes upon contact with water. Different molecular weights (80 kDa, 42.5 kDa and 16 kDa MWn) were used individually and after blending. Scanning electron microscopy analysis indicated that all matrices had an increased surface roughness relative to membranes formed after dissolving in Chloroform. However, matrices could not be made from 16 kDa MW alone. DSC analysis showed no change in the melting point of PCL. Blood vessel prototypes were made by coating a ¼ inch Teflon rod in PCL and submerging in water while membranes were created for tissue culture and tensile strength testing by coating Teflon dishes in PCL and spontaneously generating in water. Formed blood vessel prototypes (5 mm diameter and 5 to 6 cm long) were exposed to pressures between 0 to 250 mmHg in closed-loop flow system built in-house, during which dimensional changes were quantified and compliance was calculated using the equation C=(DV/V)/ DP*100 where DV is the change in volume for the corresponding change in pressure. Compliance testing showed that (abbreviation is in the order of 80:42.5:16 kDa and numbers indicate the volume proportions) decreasing the molecular weight increased the compliance. The trend was validated by the linear tensile testing results as the tensile strength decreased with blending of the weights. Elastic modulus decreases with decreased MW, validating the observed trend in compliance measurement. Eight week degradation study indicated that matrices containing low MW PCL degraded without any major changes in weight in high MW PCL containing matrices. In vitro cell cultures were conducted using mouse embryonic fibroblasts and tracked through day 4. Resazurin assay was conducted to measure growth of the cells on the scaffolds. Cytoskeletal staining was done with Alexa 688 Phalloidin to see the attachment of cells to scaffold. Cell culture results showed that formed membranes are not toxic to cells. Further, cells attached and grew on matrixes, though there is no significant difference in the specific growth rate constant (calculated assuming exponential growth phase) between different MWs and their blends. Novel process is not toxic to cells. In summary, PCL membranes and small diameter blood vessels can be generated using the novel technique. Different MW PCL can be blended and matrices can be formed which could help in optimizing degradation rate as low MW PCL degrades significantly faster than high MW PCL.

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