Separation of sperm based on rheotaxis mechanism using microfluidic device

Abstract Background Assisted reproductive technologies (ARTs) face a significant hurdle in efficiently selecting the most capable sperm population from a semen sample. In this study, we have developed an innovative microfluidic device designed to utilize rheotaxis for highly efficient sperm sorting. This novel approach allows for the effective selection of high-quality sperm populations compared to other conventional methods. Method 30 normal samples from couples undergoing ICSI cycle were included in the study. The samples were analyzed and examined in the andrology unit of the Infertility Center at Fatemieh Hospital in Hamedan. Each sample were split into three distinct groups: Group 1: initial sample (Control), Group 2: Direct Swim-Up sperm selection (DSU), and Group 3: Sperm selection with rheotaxis. We used a syringe pump connected to the microfluidic device to create optimal flow in the device. The spermatozoa underwent evaluation for concentration, motility, and morphology, mitochondrial membrane potential (MMP), and sperm DNA fragmentation index (DFI). A one-way ANOVA followed by a Student's t-test was conducted to ascertain the statistical significance of observed differences. Results Concentration (7.46 ± 2.84 vs. 56.67 ± 18.27; p < 0.0001) and DNA fragmentation (2.93 ± 2.70 vs. 21.13 ± 5.27; p < 0.0001) after selection in the rheotaxis microfluidic device were significantly lower than control group. The progressive motility (98.10 ± 2.41% vs. 44.13 ± 7.06%, p < 0.0001), normal morphology (8.36 ± 1.47% vs. 5.20 ± 1.15, p < 0.0001), MMP (99.63 ± 0.71% vs. 81.13 ± 9.19%, p < 0.0001), in the rheotaxis microfluidic device experienced a noteworthy rise in comparison to the control group. Conclusion our study demonstrates the effectiveness of the rheotaxis-based microfluidic device in selecting a high-quality sperm population, showcasing improved motility, morphology, mitochondrial membrane potential, and reduced DNA fragmentation. This advancement holds promise for enhancing assisted reproductive technologies.