Comparison of the breaking strength of polyglactin mesh in urine, serum, and cell culture media

Objectives. This study was designed to determine the durability of polyglactin woven mesh in various in vitro environments, including urine, since polyglactin 901 mesh has been considered for implementation in urinary tract reconstruction. Methods. Segments of 1 x 1-cm sterile woven and knitted polyglactin 910 mesh with and without collagen coating were exposed to the following conditions: dry (at room temperature and at 37°C, humidified air), in porcine and human serum and urine, in porcine urine over a range of pH levels, in infected urine, in cell culture media (MCDB 105 with 5% fetal bovine serum), and in cell culture media with porcine bladder fibroblasts. The mesh breaking strength was measured at 0, 12, 21, 28, and 36 days. Results. The mean breaking strength for dry, room temperature mesh segments measured 350 g for all time intervals. At day 21, the breaking strength for all mesh types in human and porcine serum, cell culture media, and cell culture media with bladder fibroblasts was less than 10% of the control, but the human and porcine urine maintained 12% to 24% of the control breaking strength (this difference did not reach statistical significance). There was no significant difference in the breaking strength in human and porcine urine or human and porcine serum. By day 38, the breaking strength for all mesh types in all solutions was less than 5% of the control breaking strength. The presence of fibroblasts increased the rate of degradation of the mesh compared with the urine, serum, and cell culture media alone. There was a significant prolongation of degradation with decreasing pH, as well as with infected urine. This prolongation was additive; in fact, all mesh types in low pH (5.0), infected urine showed minimal degradation at 38 days. Conclusions. In acidic infected urine, the durability of polyglactin 910 mesh is significantly prolonged compared with the other conditions tested. Therefore, when used in urinary tract reconstruction, as in other organ systems, the integrity of the polyglactin mesh should diminish rapidly after 3 weeks as long as the urine is kept sterile and a neutral to alkaline pH is maintained.