Preparation of well-defined calcium cross-linked alginate films for the prevention of surgical adhesions.

Abstract

Abdominal adhesions are one of the major problems associated with abdominal surgeries or abdominal trauma. There are many different therapeutic options to prevent these adhesions, for example, the application of barrier films made of biodegradable polymers like alginate. For many application relevant parameters (mechanical stability, elasticity, erosion, and mucoadhesivity of the films), the extent of cross-linking with divalent cations, such as calcium, is essential to obtain alginate films with clinically ideal properties. All these properties can eventually be strongly influenced by the composition of the films. For this reason, the manufacture of thin films (≈20 µm) was improved to accurately control the calcium content and distribution as well as the time and process of cross-linking. The aim of this work was to find the best suited method to evenly distribute the calcium ions in the alginate films and to obtain films with controlled erosion times as well as sufficient flexibility and stability. Furthermore, the influence of plasticizers on the mechanical stability and elasticity was tested to find the amount and type of plasticizers that have to be added to produce the best suited films.