A comparison of the effect of pH on the biodegradation of two synthetic absorbable sutures

The differences in hydrolytic degradation of two size 2-0 synthetic absorbable sutures, Polyglycolic acid (Dexon) and Poly(glycolide-lactide) (Vicryl), in the buffer media of three different pH levels ranging from 5.25 to 10.09, were compared in terms of the percentage retention of tensile strength. It was found that Vicryl sutures, in general, exhibited better retention of tensile strength than Dexon sutures within the studied pH range and extent of hydrolysis. When comparing Vicryl with Dexon sutures, the former was only slightly better than Dexon sutures, in the case of an acid environment. The former, however, retained better strength than the latter in a physiological pH (7.44) and under high-alkaline conditions (10.09). Among the three pH levels tested, Vicryl sutures retained the highest tensile strength in a physiological pH and showed a faster loss of tensile strength in both acidic and high-alkaline conditions. Dexon sutures, however, exhibited better retention of tensile strength in the acidic medium than in an alkaline medium. This pH dependent hydrolysis of Dexon and Vicryl sutures should command surgeons' attention in their selection of synthetic absorbable suture materials for particular needs.