Visually observable material for medical treatment

#The present invention generally pertains to a visually observable material. More specifically, the invention involves a visually observable material for medical treatment which is preferable as an adhesion preventive material, a hemostatic material and the like for biological organisms.

#When invasion occurs in a biological tissue through an operative procedure during surgery, adhesion arises via the occurrence of inflammation in the course of tissue curing at the site, so that normal functions of the tissue or organ are blocked by the adhesion, sometimes causing an undesirable post-operative complication. In the region of abdominal cavity, for example, ileus caused post-operatively by adhesion between intestine and peritoneum is a severe complication. That is, it is possible following surgery that body organs and/or tissue in the living body will tend to adhere to one another and not remain separate.

#For the purpose of preventing such post-operative adhesion, a biologically absorbable, adhesion preventive material is sometimes used to form a barrier of sorts between tissues or organs so that the organs/tissue remain separated from each other.

#FIGS. 1(A) and (B) are digital pictures showing the results of a test for visual observation in Test Example 1.

#The crosslinking polysaccharide derivative disclosed here by way of example contains at least one active ester group reactive with active hydrogen in the co-presence of an alkali, where the active ester group is preliminarily introduced in a side chain of a polysaccharide, and therefore induces a crosslinking reaction through the active hydrogen-containing group in the co-presence of an alkali.

#The polysaccharide as a raw material into which the active ester group is preliminarily introduced is described below. Because a polysaccharide molecule essentially has hydroxyl group, namely active hydrogen-containing group in itself, the polysaccharide with an active ester group introduced therein is now provided with both active ester group and active hydrogen-containing group within one molecular chain, so that the polysaccharide molecule exerts self-crosslinking ability under the reaction conditions. The self-crosslinking ability means that the active ester group and the active hydrogen-containing group react together intra-molecularly within one molecule of the polysaccharide derivative or inter-molecularly in the molecules thereof, to form covalent bonds. In case that an active hydrogen-containing group on the biological surface is used for the reaction, additionally, the crosslinking polysaccharide derivative exerts adhesiveness to the biological surface. Herein, the term molecule in the term “one molecular chain” or “intra-molecularly” means a single molecule within a covalently bound continuous zone.

#In the description below, the crosslinking polysaccharide derivative is sometimes referred to as actively esterified polysaccharide. Therefore, the crosslinking polysaccharide derivative may sometimes be referred to as polysaccharide derivative in a simple fashion.