Point-of-care (POC) tests need to be rapid, inexpensive and portable for field testing, as well as be able to provide reliable results, comparable to those obtained by laboratory-based methods. The ability to upload and share data wirelessly would be key to expanding its use in controlling disease outbreaks and for epidemiological reporting.
A recent publication in Analytical Chemistry reports the design, construction, and characterization of a disposable, mobile microfluidic chip sensing platform that is integrated with a smartphone for multiplexed analysis of disease-specific DNA sequences. The approach utilizes on-chip loop-mediated isothermal amplification (LAMP) with EvaGreen® as the reporter dye. Capable of simultaneously performing 10 parallel assays, the system can detect target nucleic acid sequences from a 15 uL droplet of test sample in ~ 30 minutes. Fluorescent products are visualized by the smartphone camera, data automatically analyzed by the smartphone software, and results wirelessly uploaded to a cloud-based storage and reporting service.
In an accompanying publication, the same researchers have extended this smartphone-based POC approach for the detection of Zika, Dengue and Chikungunya viruses directly from whole blood. Their platform couples on-chip sample processing with EvaGreen®-based real-time reverse-transcription LAMP (RT-LAMP) achieving high specificity and clinically relevant sensitivity for pathogen detection.
A picture of the smartphone microfluidic chip based detection system with a QR barcode system for identification (left); Image taken by the smartphone camera showing EvaGreen® fluorescent products for the four types of equine pathogen-specific DNA sequences at the endpoint of the assay (right). Image reprinted with permission from Chen W, Yu H, et al. Mobile Platform for Multiplexed Detection and Differentiation of Disease-Specific Nucleic Acid Sequences, Using Microfluidic Loop-Mediated Isothermal Amplification and Smartphone Detection.Analytical Chemistry doi: 10.1021/acs.analchem.7b02478. Copyright 2017 American Chemical Society.
To read the original articles, click the links below.
Chen W, Yu H, et al. Mobile Platform for Multiplexed Detection and Differentiation of Disease-Specific Nucleic Acid Sequences, Using Microfluidic Loop-Mediated Isothermal Amplification and Smartphone Detection. Anal Chem. 2017 Nov 7;89(21):11219-11226. doi: 10.1021/acs.analchem.7b02478.
Ganguli A, Ornob A, et al. Hands-free smartphone-based diagnostics for simultaneous detection of Zika, Chikungunya, and Dengue at point-of-care. Biomed Microdevices. 2017 Aug 22;19(4):73. doi: 10.1007/s10544-017-0209-9.