Acrylate pressure-sensitive adhesives tape as cover membrane for preventing ultrasound probes from cross-infections

Abstract Ultrasonic diagnosis is convenient and effective. However, insufficient and improper cleaning or disinfection will not only cause cross-infection, but also damage the outermost acoustic lens which is the most critical acoustic part of the medical ultrasonic imaging system. Herein, acrylate pressure-sensitive adhesive (PSA) tapes, intended as coverings for protecting ultrasound probes to prevent cross-infections, were prepared by the transfer coating method using acrylate copolymer as the adhesive and polyethylene film as the substrate. Ultrasound testing using PSA tape as a barrier for the probe was carried out on a skin-like silicone puncture phantom and the distal forearm of a volunteer. The clarity of ultrasonic images analyzed by Image J Software based on gray value and judged by the clinician was compared. Effect of acrylate copolymers with different molecular weights synthesized through free radical polymerization by adjusting the amount of solvent (ethyl acetate) and crosslinker (aluminum acetylacetonate) on adhesive properties and clarity of ultrasonic images were investigated in detail. Results showed that the shear strength of PSA tapes improved with increasing molecular weight of acrylate copolymer, however, tack and 180° peel strength showed a downward trend. The formation of a cross-linked network among polymer chains also greatly improved the shear strength of PSA tapes to meet the requirements of ultrasound probe covers, such as ‘easy to adhere and peel from the ultrasound probe’, ‘without adhesive residue on the surface of the ultrasound probe’ and ‘less impact on the clarity of ultrasonic images’. Viscoelastic adhesive layer of tape replaces the coupling gel between ultrasound probe and PSA tape. The ease of preparation, convenience of use, and effectiveness of acrylate PSA tapes indicate that they have broad application prospects for sonographic examinations.