Mucoadhesive polymer films for tissue retraction in laparoscopic surgery: Ex-vivo study on their mechanical properties
Issue title: Frontiers in Biomedical Engineering and Biotechnology – Proceedings of the 2nd International Conference on Biomedical Engineering and Biotechnology, 11–13 October 2013, Wuhan, China
Affiliations: Institute of Medical Science and Technology (IMSaT), University of Dundee, Wilson House, MediPark, Dundee DD2 1FD, UK | School of Chemistry, University of St Andrews, North Haugh, St Andrews KY16 9ST, UK | School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK
Abstract: Safe and effective manipulation of soft tissue during laparoscopic procedures can be achieved by the use of mucoadhesive polymer films. A series of novel adhesive polymer films were formulated in house based on either Carbopol or Chitosan modified systems. The mechanical properties of the polymers and their adherence to bowel were evaluated using ex-vivo pig bowel immersed in 37°C water bath and connected to an Instron tensiometer. Young's modulus was 300 kPa for the Carbopol-polymer and 5 kPa for the Chitosan-polymer. The Chitosan-polymer exhibited much larger shear adhesion than its tensile adhesion: 3.4 N vs. 1.2. Both tensile and shear adhesions contributed to the large retraction force (2.6 N) obtained during l polymer-bowel retraction testing. Work of adhesion at the polymer/serosa interface, defined as the area under the force curve, was 64 mJ, which is appreciably larger than that reported with existing polymers. In conclusion, adhesive polymers can stick to the serosal side of the bowel with an adhesive force, which is sufficient to lift the bowel, providing a lower retraction stress than that caused by laparoscopic grasping which induces high localized pressures on the tissue.
