). Approximately 10 mg of the samples were heated from room temperature to 600��C at a heating rate of 10��C/min then in a N2 atmosphere. Mechanical properties testing Tensile tests were conducted according to ISO 527�C2:1993(E) on an Instron Mechanical tester (Series IX Automated Materials Testing System, INSTRON Corp.) equipped with 100 N load cell. Dumb bell specimens were cut using type 5B die and pulled at a rate of 100 mm/min. Tensile strength (MPa) and elongation at break (%), Youngs modulus (MPa), % strain at break and modulus of toughness (KPa) were calculated, and the stress vs. % strain plotted. Contact angle measurement The hydrophobicity or hydrophilicity is usually characterized by the water contact angle technique.30,31 The samples used for this analysis was thoroughly washed and cleaned.
Deionized water was used for the study. The water in air contact angles of the polyester films were measured at room temperature (approx. 23��C) using the sessile drop method by a video-based contact angle measuring device (DataPhysics OCA15 plus) and imaging software (SCA20 software) within 10 sec after introduction of water droplet. The contact angle formed between a sessile drop and the film is directly related to the forces at the liquid-solid interface, indicating the hydrophilic or hydrophobic characteristics of the surface. Four independent measurements at different sites were averaged. The contact angle changes over time were also monitored. Five individual experiments were performed for the contact angle study. The results were presented as means �� standard deviation.
In vitro degradation Phosphate Buffered Saline (PBS, pH 7.4, 0.1 M) was prepared by dissolving 17.97 g of disodium hydrogen phosphate, 5.73 g of monosodium hydrogen phosphate and 9 g of sodium chloride in 1 L of distilled water. The Polyester sample (10 x 10 x 1.5 mm) was placed in a container containing 10 ml phosphate buffer saline and incubated at 37��C for one week. The samples were removed and dried under vacuum. The mass loss was calculated by comparing the initial mass (Wo) with that at the given point (Wt), as shown in Equation (1). Six individual experiments for a period of four weeks were performed for the degradation test. The results were presented as means �� standard deviation. Mass loss (%) = Preparation of porous films Preparation of porous scaffolds was done by salt leaching method.
32,33 The prepolymer formed was dissolved in acetone, followed by addition of sieved salt (70%), which serves as the porogen. The resulting slurry was put in an oven for post polymerization (70��C for 5 d). The salt in the resultant slurry was leached out by successive washing with double distilled water for 3 d. The film was then freeze-dried for 24 h and stored in a dessicator. The range of pore Drug_discovery sizes was determined by gold coating the sample and observing by scanning electron microscopy (HITACHI model, S-2400).