title: Solar-thermal complex sample processing for nucleic acid based diagnostics in limited resource settings.
abstract: The use of point-of-care (POC) devices in limited resource settings where access to commonly used infrastructure, such as water and electricity, can be restricted represents simultaneously one of the best application fits for POC systems as well as one of the most challenging places to deploy them. Of the many challenges involved in these systems, the preparation and processing of complex samples like stool, vomit, and biopsies are particularly difficult due to the high number and varied nature of mechanical and chemical interferents present in the sample. Previously we have demonstrated the ability to use solar-thermal energy to perform PCR based nucleic acid amplifications. In this work demonstrate how the technique, using similar infrastructure, can also be used to perform solar-thermal based sample processing system for extracting and isolating Vibrio Cholerae nucleic acids from fecal samples. The use of opto-thermal energy enables the use of sunlight to drive thermal lysing reactions in large volumes without the need for external electrical power. Using the system demonstrate the ability to reach a 95°C threshold in less than 5 minutes and maintain a stable sample temperature of +/- 2°C following the ramp up. The system is demonstrated to provide linear results between 10(4) and 10(8) CFU/mL when the released nucleic acids were quantified via traditional means. Additionally, we couple the sample processing unit with our previously demonstrated solar-thermal PCR and tablet based detection system to demonstrate very low power sample-in-answer-out detection.
authors.affiliation: School of Electrical and Computer Engineering, Cornell University, Ithaca, NY, USA.
authors.forename: Abdurrahman
authors.initials: A
authors.lastname: Gumus
authors.affiliation: Applied and Engineering Physics, Cornell University, Ithaca, NY, USA.
authors.forename: Syed
authors.initials: S
authors.lastname: Ahsan
authors.affiliation: College of Veterinary Medicine, Cornell University, Ithaca, NY, USA.
authors.forename: Belgin
authors.initials: B
authors.lastname: Dogan
authors.affiliation: Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA.
authors.forename: Li
authors.initials: L
authors.lastname: Jiang
authors.affiliation: Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA.
authors.forename: Ryan
authors.initials: R
authors.lastname: Snodgrass
authors.affiliation: Department of Biomedical Engineering, Cornell University, Ithaca, NY, USA.
authors.forename: Andrea
authors.initials: A
authors.lastname: Gardner
authors.affiliation: Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA.
authors.forename: Zhengda
authors.initials: Z
authors.lastname: Lu
authors.affiliation: College of Veterinary Medicine, Cornell University, Ithaca, NY, USA.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Simpson
authors.affiliation: Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA.
authors.forename: David
authors.initials: D
authors.lastname: Erickson
keywords: (170.4580) Optical diagnostics for medicine; (350.6050) Solar energy