A rapid sample-to-answer analytical detection of genetically modified papaya using loop-mediated isothermal amplification assay on lab-on-a-disc for field use. (15th February 2019)

• Record Type: Journal Article
• Authors: Loo, Jacky Fong-Chuen; But, Grace Wing-Chiu; Kwok, Ho-Chin; Lau, Pui-Man; Kong, Siu-Kai; Ho, Ho-Pui; Shaw, Pang-Chui
• Is Part Of: Food chemistry. Volume 274(2019)
• Page Start: 822
• Page End: 830
• Publication Date: 2019-02-15
• Subjects: GM genetically modified -- GMO genetically modified organism -- LAMP loop-mediated isothermal amplification -- LOAD lab-on-a-disc -- PCB printed circuit board -- PCR polymerase chain reaction -- PDMS polydimethylsiloxane -- P-35S cauliflower mosaic virus 35S promoter -- PRSV Papaya Ringspot Virus -- RT-LAMP real­time loop­mediated isothermal amplification; Lab-on-a-disc -- Loop­mediated isothermal amplification -- Sample-to-answer -- Transgenic food screening -- On-site detection; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2018.09.049
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Using a lab-on-a-disc (LOAD) approach, sample-to-answer detection of genetically modified (GM) papaya was designed. A detectable signal was achieved in 20 min, which is faster than the traditional benchtop setup. The fluorescent signal from the LOAD platform could be observed by eye and quantified by smartphone app. Detection limit for GM screening was 10 pg/µL DNA and 0.02 µL papaya juice. On-site testing of transgenic food in our portable LOAD platform was achieved. Abstract: With genetically modified (GM) food circulating on the market, a rapid transgenic food screening method is needed to protect consumer rights. The on-site screening efficiency of GM food testing is low. We report rapid sample-to-answer detection of GM papayas with loop-mediated isothermal amplification (LAMP) and a compact, portable, integrated microfluidic platform using microfluidic lab-on-a-disc (LOAD). GM samples were differentiated from non-GM papaya, based on the detection of a specific GM (P-35S (Cauliflower mosaic virus 35S promoter)) and non-GM DNA marker (papain) in 15 min. The detection limits for DNA and juice from papaya were 10 pg/µL and 0.02 µL, respectively. Our LOAD platform is a simple and robust solution for GM screening, which is anticipated to be a foundation for on-site testing of transgenic food.