A portable device for nucleic acid quantification powered by sunlight, a flame or electricity


A decentralized approach to diagnostics can decrease the time to treatment of infectious diseases in resource-limited settings, yet most modern diagnostic tools require stable electricity and are not portable. Here, we describe a portable device for isothermal nucleic acid quantification that can operate with power from electricity, sunlight or a flame, and that can store heat from intermittent energy sources for operation when electrical power is not available or reliable. We deployed the device in two Ugandan health clinics, where it successfully operated through multiple power outages, with equivalent performance when powered via sunlight or electricity. A direct comparison between the portable device and commercial quantitative polymerase chain reaction machines for samples from 71 Ugandan patients (29 of which were tested in Uganda) for the presence of Kaposi’s sarcoma-associated herpesvirus DNA showed 94% agreement, with the four discordant samples having the lowest concentration of the herpesvirus DNA. The device’s flexibility in power supply provides a needed solution for on-field diagnostics.

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Fig. 1: TINY system overview.
Fig. 2: Construction and design of TINY.
Fig. 3: TINY heating characterization.
Fig. 4: LAMP assay performed using multiple heating methods.
Fig. 5: Standard curves for qPCR and LAMP.
Fig. 6: Analysis of 42 human skin samples for KSHV DNA.
Fig. 7: Analysis of human samples by TINY in Uganda.

Data availability

All data supporting the findings in this study are available within the Article and its Supplementary Information. Additional data are available from the corresponding authors upon request.


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We would like to thank P. Namaganda, M. Laker-Oketta, H. Byakwaga, P. Kyomuhangi, E. Mande and O. Mbabazi for their work at the Infectious Diseases Institute. We also thank O. Imsdahl, J. Gutierrez and J. Sullivan (Cornell University) for assistance in fabrication of the TINY prototypes. Special thanks to M. Kirya for assisting during visits of rural Ugandan health clinics in July 2016. This work was performed in part at the Cornell NanoScale Facility, a member of the National Nanotechnology Coordinated Infrastructure (NNCI), which is supported by the National Science Foundation (grant ECCS-1542081). The authors acknowledge support for this research from the US National Cancer Institute under grant UH2 CA202723. This study is based upon work supported by the National Science Foundation Graduate Research Fellowship under grant no. 1144153.

Author information

R.S. and A.G. wrote the manuscript with review from all other authors. R.S., V.K., J.D., E.C. and D.E. developed the TINY device. All authors were responsible for design of experiments. R.S., A.G. and J.D. conducted experiments. A.S. and J.M. coordinated collection of human samples. R.S. and A.G. analysed the data. R.S. generated the figures and tables.

Correspondence to Jeffrey Martin or Ethel Cesarman or David Erickson.

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The authors have submitted a patent for the TINY system.

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Snodgrass, R., Gardner, A., Semeere, A. et al. A portable device for nucleic acid quantification powered by sunlight, a flame or electricity. Nat Biomed Eng 2, 657–665 (2018). https://doi.org/10.1038/s41551-018-0286-y

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