Sutures, stent from nanohybrid material
doi:10.1038/nindia.2018.126 Published online 27 September 2018
Researchers have synthesised a candidate nanohybrid material that may be used to make stents to restore and sustain blood flow in a clogged artery1. This hybrid material could also be used to make self-tightening sutures for healing wounds.
Shape-memory materials change from a temporary intermediate shape back to their fixed, permanent shape in response to external stimuli such as temperature. However, biomedical devices such as stents made from conventional shape-memory materials cannot be properly loaded with drugs. After a few years of use, such devices leach materials, unleashing toxic effects.
In search of a better material, scientists from the Indian Institute of Technology (Banaras Hindu University) in Varanasi and the Bhabha Atomic Research Centre in Mumbai, India, prepared the nanohybrid material using polyurethane, a soft polymer and a specific nanoclay.
The researchers, led by Pralay Maiti, found that the nanohybrid deformed above a transition temperature. On cooling, the nanohybrid regained its permanent shape at a suitable temperature.
The shape-recovery temperature of the nanohybrid was close to the physiological temperature observed in most mammals, including humans. Besides, studies with specific mice cells showed that these cells easily adhered to the nanohybrid and remained alive, indicating that the nanohybrid material is biocompatible.
Using its excellent shape-memory property, the nanohybrid can be placed in internal organs of the body through a catheter. Since the nanohybrid contains a soft polymer, it can locally elute drugs, allowing disease control without side effects, says Maiti.
1. Biswas, A. et al. Biodegradable toughened nanohybrid shape memory polymer for smart biomedical applications. Nanoscale. 10, 9917 (2018)