ABILITY OF CATIONIC AND NEUTRAL HYDROGELS BASED ON N-ISOPROPYLACRYLAMIDE TO BIND EQUINE SPERMATOZOA

EBEL, FRANCISCA; LIAUDAT, ANA C.; CAPELLA, VIRGINIA; RIVAROLA, CLAUDIA R.; BOSCH, PABLO

Congreso; Reunión Sociedades Biociencias 2019 - SAIC -SAFE - SAB - SAP; 2019

PNIPAm (poli(N-isopropylacrylamide) based hydrogels are biocompatible materials extensively used in biomedicine. The aim of this study was to evaluate the ability of PNIPAm hydrogels to attach stallion spermatozoa. PNIPAm was co-polymerized with cationic 3-(acrylamido propyl) trimethylammonium chloride (APTA) or neutral N-[Tris (hydroxymethyl) methyl] acrylamide (HMA) monomers. Studied copolymers contained 5%APTA, 10%APTA, 15%APTA, 20%HMA and 20%HMA semi-interpenetrated with hyaluronic acid (20%HMA-HA, 1mg/mL). Each hydrogel was placed in a culture dish containing TALP medium and fresh stallion sperm suspension was added. The percentage of sperm attached to the surfaces was determined from the difference between the number of sperm initially added into the culture dish and the recovered non-bound cells after incubation (30 min at 37°C in 5% CO2). Sperm that were exposed to -20°C for 60 min to render them non-viable were added to hydrogel-containing dishes, which served as negative controls. Higher percentage of spermatozoa was attached to the surface APTA compared to that on the HMA hydrogels (P0.05). The semi-interpenetration of 20%HMA hydrogels with HA did not increase the percentage of spermatozoa bound to the surface (20%HMA: 43.4±7.9%; 20%HMA-HA: 50.5±4.9%, P>0.05). Few non-viable spermatozoa were observed attached to hydrogels. In conclusion, cationic PNIPAm hydrogels could be an efficient support and binding substrate to adhere viable equine sperm, since stallion spermatozoa attaches more efficiently on them. It is expected that this strategy will allow the development of a technique for sperm selection, which isolates the cell subpopulation with high structural and functional quality characteristics, improving the efficiency of assisted reproduction techniques in horses.This work was supported by grants from UNRC and MinCyT, Córdoba