Bacterial pathogen detection using laser-structured paper-based diagnostic sensors

Antimicrobial resistance has been recently identified by the World Health Organisation as a global threat and the need for novel diagnostic tools has been stressed. Current routine empirical antibiotic therapy protocol involves laboratory-based bacterial culture testing which can take up to 2-3 days. However, if the specific microbe species causing an infection can be quickly identified earlier on, it will allow doctors to prescribe a specific targeted antimicrobial instead of using a broad spectrum antimicrobial. In this work, we will present our preliminary results on the use of a laser-based fabrication technique of paper-based diagnostic tests via photo-polymerisation. The technique allows the creation of hydrophobic barriers through the whole thickness of the paper, and therefore the creation of fluidic channels and test zones in many different shapes, sizes and patterns. The laser-based direct-write procedure is non-contact, non-lithographic and mask-less and uses a low-power 405nm diode laser. The laser-structured paper can then be infused with chromogenic agars that allow the growth and detection of different bacteria. These devices are analogues of the commonly available agar plates and will allow the timely detection of multiple pathogens at the point-of-care. These paper-based diagnostic sensors fabricated via our laser-based technology are cheap, easy-to-use and allow rapid testing of either pathogens or their antimicrobial resistance to antibiotics.