• He, Peijun
• Keevil, Charles
• Katis, Ioannis
• Sherwin, Susanna
• Eason, Robert W.
• Sones, Collin

Abstract

Drug resistant bacteria are a major health problem and the growing resistance to antibiotics in organisms such as Escherichia Coli and Staphylococcus aureus, poses a clinically significant challenge in hospital medicine. Early diagnosis and prompt antibiotic treatment of any such infection is important for clinical recovery and prevention of serious antimicrobial resistance (AMR) - a key objective of the World Health Organization. Current routine empirical antibiotic therapy protocol for diagnosis of such pathogens involves a preliminary laboratory-based bacterial culture testing using agar-plates 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. <br/>We present here the use of paper devices patterned via a proprietary laser-based polymerisation technique for detection and susceptibility testing of bacterial pathogens. The technique allows the creation of hydrophobic barriers inside and on the surface 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 405nm diode laser. The laser-structured paper can then be infused with chromogenic agars that allow the growth and detection of different bacteria. As shown in Fig. 1a, antibiotics can be added to the individual test zones therefore allowing for testing of the susceptibility/resistance of the bacteria such as MRSA and MSSA to those antibiotics. Using more complex designs and combinations of the growth media (Fig. 1b), multiplexed detection of different bacteria such as Staphylococcus and E.Coli can also be achieved in a single device. We envisage that these cheap and easy-to-use devices will serve as point-of-care analogues to the agar plates used routinely in pathological labs for detection of bacterial infections.

Topics

• impedance spectroscopy
• surface
• laser emission spectroscopy
• susceptibility