The sensor (IMAGE) Johns Hopkins University Caption The sensor material can be placed on any type of surface, from doorknobs and building entrances to masks and textiles. Credit Kam Sang Kwok and Aishwarya Pantula/Johns Hopkins University Usage Restrictions None License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.