doi:10.1038/nindia.2014.93 Published online 7 July 2014
Researchers have developed biocompatible and biodegradable polyurethane films based on castor oil or polypropylene glycols that have various carbohydrates as crosslinkers1. These films could potentially be used in adhesive skin patches for delivering drugs through the skin as dressings for wounds.
Polyurethanes are excellent polymers for synthesizing biocompatible drug-delivery systems, except that existing polyurethane-based drug carriers are thermally unstable and show poor mechanical strength.
To develop polyurethane-based drug carriers with better mechanical strength, the researchers made them using castor oil or polypropylene glycols and four different carbohydrates as crosslinkers: glucose, sucrose, cellulose and starch. They then prepared films from these polyurethanes and tested their mechanical properties.
Films containing glucose and cellulose showed the best elongation properties, whereas films with starch and cellulose exhibited the best tensile properties. The tensile strength and elongation properties of the films reflect their mechanical strength and elasticity, respectively. Films with high values are resistant to wear and tear when used in biomedical applications.
The researchers exposed the films to normal lung cells and buried them in microbe-containing soil to prove that they were biocompatibile, nontoxic and biodegradable. In addition, the films swelled in organic solvents used to dissolve drugs. This suggests that drug molecules can be bound to the films by immersing the films in drug solutions. “Besides their potential applications in drug delivery and wound dressings, these films seem to be promising materials for making artificial organs,” says lead researcher Sonal Thakore.
The authors of this work are from: Department of Chemistry, Faculty of Science, M .S. University of Baroda, Vadodara, and Research and Development Centre, Gujarat Narmada Valley Fertilizers and Chemicals Company Limited, Bharuch, India.
1. Solanki, A. et al. Structure–property relationships and biocompatibility of carbohydrate crosslinked polyurethanes. Carbohydr. Polymer 110, 338–344 (2014)