Development Of A Wearable Device For Nucleic Acid Detection

The global HIV/AIDS pandemic has resulted in 39 million deaths to date,and there are currently more than 35 million people living with HIV worldwide.Currently available diagnostic assays,which include polymerase chain reaction(PCR),enzyme-linked immunosorbent assay(ELISA),and western blot(WB),are time consuming,technologically complex and inappropriate for decentralized laboratories.These diagnostic technologies are ill-suited for use in low-and middle-income countries,where the challenge of the HIV/AIDS pandemic is most severe.Compared to nucleic acid detection,routine antibody-based screening tests are not applicable to the diagnosis of infants born to HIV-infected mothers.The gold standard for early infant diagnosis,DNA PCR,requires resources that are unavailable in poor settings,and no point-of-care HIV-1 DNA test is currently available.Here,we developed a wearable microfluidic device combined recombinase polymerase amplification(RPA)for simple and rapid amplification of HIV-1 DNA using human body heat.The human body temperature at the human wrist varied from 33 to 34℃ in the ambient environment,which is sufficient to perform RPA reactions.With the aid of a cellphone-based fluorescence detection system,this device detected HIV-1 DNA quantitatively ranging from 102 to 105 copies/mL with a linearity of 0.98 in 24 minutes.These results demonstrate that this wearable point-of-care(POC)nucleic acid testing method is advantageous over traditional PCR and other isothermal nucleic acid amplification methods in terms of time and portability.This wearable microfluidic device in conjunction with a cellphone-based fluorescence detection system can potentially be used for detection HIV-1 and adapted for POC detection of a broad range of infectious pathogens in resource-limited settings.