Simulation of Suture Production by Microfluidic Spinning to Optimise Flow Rates and Channel Length

Sutures are still important aids in surgery especially where mechanical support and strength is needed to hold the wound edges together and microfluidic spinning is one of the newest and most efficient methods to produce sutures. In this work, using software simulation with COMSOL along with some experimental data, a quantitative criterion for designing microfluidic channel and flow rates is proposed for solvent extraction technique. Results obtained can be generalized for all polymer-solvent-nonsolvent systems. We have found that if at the end of the channel, the nonsolvent diffuses into the polymer solution in a way that it occupies 40% of its width in a concentration higher than the critical concentration for precipitation, the fiber will be formed without clogging the microchannel. Also we have found that flow rates have significant effect on suture diameter. The application of the proposed criterion is in designing the length and width of microfluidic channels especially after the junction.