A team of researchers from the Indian Institute of Science, Bangalore, has developed a novel polymer that can accelerate healing of bone fractures. Dr. Kaushik Chatterjee, Assistant Professor in the Department of Materials Engineering in collaboration with Professor Giridhar Madras from Chemical Engineering at IISc are working on developing polymers that can serve as templates to facilitate bone growth. The team is working on developing maltitol-based biodegradable polyesters for accelerated healing.
Bones are one of the most important structures in our body providing the much needed support and protecting our organs. They undergo wear and tear and can break as a result of an injury or diseases like osteoporosis, leading to a fracture. Our body can heal fractured bones on its own, but this needs support. Often, healing can be very slow owing to old age. Moreover, some fractures like hip fractures, take an enormous time to heal making the patient bed-ridden for a better part of their lives.
According to a report from the World Health Organization, around 9 million hip fractures occurred during the year 2000 worldwide and this number is expected to increase steadily. Currently, treatment involves using grafts, either from the patient’s own body (autograft) or from a cadaver (allograft). However, the success rates of these transplants are not high, prompting the development of newer strategies to heal bone fractures rapidly.
Tissue engineering has immense potential to solve this issue and has become a hot area of research. Scientists are looking for the perfect material that is biodegradable and provides a biocompatible scaffold with mechanical properties that mimic the hierarchical structure of bone. “As the bone tissue starts to regenerate, the plastic must be resorbed and excreted by the body in a safe manner. Thus, we worked with maltitol, a sugar substitute/sweetener to prepare such plastics with other compounds that are used to prepare tablets/drugs. The advantage is that as the plastic degrades over time, maltitol and the other constituents that are released are not toxic and can be safely removed from the body,” says Prof. Chatterjee.
The researchers have shown that the properties of the new polymer synthesized using maltitol can be tuned to match clinical needs. Synthetic biodegradable polymers are preferred over natural polymers, metals and ceramics, because of their flexibility in tailoring the physical properties, tissue response, biodegradability and biocompatibility. "The choice of the precursors used to prepare the polymers of different stiffness can be made to tailor the needs of the different bone tissues in the human body, which can vary significantly from limbs to skull" says Janeni Natarajan, the PhD student who worked on this project .
Sugar-based alcohols have been widely used in biodegradable polyesters and are endogenous to human metabolism. So is it toxic? As a part of the study, the researchers have tested if the use of maltitol-based polymers were toxic to cells of the human body and found that these polymers were cytocompatible with no signs of cell death.
This is a great step in the field of materials engineering and biomedicine. Prof. Giridhar believes that that there have been significant breakthroughs in engineering such materials in recent years and with the rapid advancements in this field many new treatment options will become available to surgeons in future.
Janeni Natarajan is a Ph.D. student in the Centre for Nano Science and Engineering, IISc.
Dr. Giridhar Madras is a Professor in the Dept. of Chemical Engineering, IISc.
Dr. Kaushik Chatterjee is an Assistant Professor in the Dept. of Materials Engineering, IISc.
About the paper:
The report has been published in RSC Advances and can be accessed online at http://pubs.rsc.org/en/content/articlepdf/2016/ra/c6ra02058e