# tech: it repels everything with some beneficial exceptions

<< Researchers at McMaster University have solved a vexing problem by engineering surface coatings that can repel everything, such as bacteria, viruses and living cells, but can be modified to permit beneficial exceptions. >>

Researchers design "smart" surfaces to repel everything but targeted beneficial exceptions. McMaster University. Oct 24, 2018

https://phys.org/news/2018-10-smart-surfaces-repel-beneficial-exceptions.html

Tohid Didar. Researchers design "smart" surfaces, creating promise for safer implants and more accurate diagnostic tests. Oct 24, 2018.

https://www.eng.mcmaster.ca/news/researchers-design-smart-surfaces-creating-promise-safer-implants-and-more-accurate-diagnostic