Porous and sutureless bioelectronic patch with retained electronic properties under cyclic stretching

The effect of introducing pores in bioelectronic patches was investigated. Using laser ablation, pores of different sizes and distances were introduced in a chitosan film. Polyaniline was then polymerised on the surface to produce bioelectronic patches with tailored large surface areas and pore densities varying from ∼4% to 40%. Conductivity measurements confirmed that the polyaniline formed a connected conductive network with values ranging from 0.22 ± 0.04 S cm−1 (lowest porosity) to 0.08 ± 0.01 S cm−1 (highest porosity). Their mechanical properties also varied as function of porosity. As a potential bioelectronic patch for cardiac applications, electronic fatigue was investigated in response to cyclic stretching mimicking the heart contraction cycle. Patches exhibited either a decrease in resistance (low porosity patch) or a minimal increase in resistance (<25% for higher porosities) over 1000 stretches. Incorporated in a chitosan adhesive, porous patches could be photo-adhered to tissue in a minimally invasive technique using LED light. This study demonstrated the fabrication of porous sutureless patches using an optimal fabrication technique that does not compromise their functional properties such as mechanical and electronic characteristics.