Development of a Smartphone-Integrated Reflective Scatterometer for Bacterial Identification

Abstract

We present a smartphone-based bacterial colony phenotyping instrument using a reflective elastic light scattering (ELS) pattern and the resolving power of the new instrument. The reflectance-type device can acquire ELS patterns of colonies on highly opaque media as well as optically dense colonies. The novel instrument was built using a smartphone interface and a 532 nm diode laser, and these essential optical components made it a cost-effective and portable device. When a coherent and collimated light source illuminated a bacterial colony, a reflective ELS pattern was created on the screen and captured by the smartphone camera. The collected patterns whose shapes were determined by the colony morphology were then processed and analyzed to extract distinctive features for bacterial identification. For validation purposes, the reflective ELS patterns of five bacteria grown on opaque growth media were measured with the proposed instrument and utilized for the classification. Cross-validation was performed to evaluate the classification, and the result showed an accuracy above 94% for differentiating colonies of E. coli, K. pneumoniae, L. innocua, S. enteritidis, and S. aureus.

Detection and confirmation of Salmonella Typhimurium by smartphone-enabled optomechanical platform

“…Recent research focuses on enhancing biosensor sensitivity, often employing nanomaterials and novel techniques for signal amplification [13,14]. Furthermore, smartphone-based biosensors, leveraging optical features, have emerged as cost-effective and portable solutions for pathogen detection, promising advances in food safety [15][16][17][18].…”

Design of a portable fluorescence imaging platform for on-site detection target analyte by loop-medicated isothermal amplification

“…Many portable instruments were proposed to reduce time-to-detection period and provide rapid detection results [6][7][8][9][10]. In particular, smartphone has been used as a main controller and detection device in many applications [11,12]. Here we are presenting an on-site detection platform that incorporates the loop-medicated isothermal amplification (LAMP) into a portable battery-operated fluorescence detection system.…”

Design of real-time pathogen monitoring device for sampled food products during shipment

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