Improvement of the Hemocompatibility of PET Surfaces Using Different Sulphated Polysaccharides as Coating Materials

Abstract

In this study, sulphated polysaccharides were investigated in respect to their blood compatibility properties (hemocompatibility). Pure chitosan was treated with sulphating agents such as SO(3)/pyridine complex and chlorosulfonic acid (HClSO(3)) to obtain 3,6-O-sulfochitosan with low and high concentration of sulfur. These synthetically derived materials and the commercially available sulphated polysaccharides heparin and dextran sulfate, both with high concentrations of sulfur, were coated onto PET foils to act as surfaces with strong antithrombotic activity. This treatment should lead to better blood compatibility properties of PET materials for medical applications. To examine this, the optimized free hemoglobin method was applied to determine the antithrombotic activity of these surfaces. Glass as the standard thrombotic surface and a heparin-coated PET surface as a surface well-known for its strong antithrombotic activity were used as internal references. The experiments showed that dextran sulfate and sulphated chitosan with high concentrations of sulfur demonstrated the same antithrombotic activity as heparin over the whole period of measurement time. In addition, a relationship between the sulfur concentration in these sulphated polysaccharides and their blood compatibility properties can be demonstrated in this article.

Semi‐Synthetic Polysaccharide Sulfates as Anticoagulant Coatings for PET, 1 – Cellulose Sulfate

“…The same has been reported for PET-Ch. [4] This finding is in accordance to the fact that PS-NH 2 had also no effect on APTT within the tested concentration range (data not shown). BAEA-C-coated PET foils were not included in the clotting time determination studies because QCM-D studies demonstrated that both 6-deoxy-6-aminocelluloses are equally capable to act as anchor layer for CS adsorption.…”

“…[4,15] In a previous work, the important measure- ment parameters were optimized toward studying the blood coagulation on polysaccharide-coated PET foils. [16] The samples were incubated with fresh human blood, which resulted in the formation of a blood clot on the surface.…”

“…The anticoagulant activity achieved by CS 3 adsorption is, within the error of the clotting time determination method, equal to the effects obtainable by using heparin (see Figure 5), dextran sulfate, or chitosan sulfate (see ref. [4]) with high degrees of sulfation.…”

“…[1,2] However, PET shows only moderate biocompatibility regarding anticoagulant and antithrombotic properties and thus requires surface modification, e.g., by plasma treatment or binding of anticoagulants. [2][3][4] Heparin, a sulfated glucosaminoglycan, is widely used for the later. [5,6] However, it also possesses several drawbacks.…”

Synthesis of a polyurea from a glucose- or mannose-containingN-alkyl urea peptoid oligomer

“…24 High and low sulfated chitosan can be obtained by using different sulfur-based reagents, where SO 3 /pyridine gave high sulfated chitosan and low sulfated chitosan can be generated with chlorosulfuric acid. 25 Polyurethanes have been used as blood-contacting biomaterials, including catheters, blood filters, blood tubing, due to their excellent mechanical properties, such as strength and elasticity. 26 Several commercial polyurethanes are marketed including Biomer, Pellethane, Mitrathane, and Tecoflex.…”