Fieldwork-based determination of design priorities for point-of-use drinking water quality sensors for use in resource-limited environments

Abstract

Improved capabilities in microfluidics, electrochemistry, and portable assays have resulted in the development of a wide range of point-of-use sensors intended for environmental, medical, and agricultural applications in resource-limited environments of developing countries. However, these devices are frequently developed without direct interaction with their often-remote intended user base, creating the potential for a disconnect between users' actual needs and those perceived by sensor developers. As different analytical techniques have inherent strengths and limitations, effective measurement solution development requires determination of desired sensor attributes early in the development process. In this work, we present our findings on design priorities for point-of-use microbial water sensors based on fieldwork in rural India, as well as a guide to fieldwork methodologies for determining desired sensor attributes. We utilized group design workshops for initial identification of design priorities, and then conducted choice-based conjoint analysis interviews for quantification of user preferences among these priorities. We found the highest user preference for integrated reporting of contaminant concentration and recommended actions, as well as significant preferences for mostly reusable sensor architectures, same-day results, and combined ingredients. These findings serve as a framework for future microbial sensor development and a guide for fieldwork-based understanding of user needs. OPEN ACCESSCitation: Bono MS, Jr., Beasley S, Hanhauser E, Hart AJ, Karnik R, Vaishnav C (2020) Fieldworkbased determination of design priorities for pointof-use drinking water quality sensors for use in resource-limited environments. PLoS ONE 15(1): e0228140. https://doi.org/10.

Electrochemical Strategy for Low-Cost Viral Detection

“…We chose an electrochemical 28 − 33 readout to detect Cas12a trans -cleavage activity rather than a fluorescent 27 , 34 − 39 or colorimetric 34 − 37 readout; electrochemical readout is favorable for point-of-care applications in LRS due to its sensitivity, low cost, and direct transduction to easily quantifiable electric signals via portable and easy-to-use electrochemical hardware. 40 , 41 …”

“…We used CRISPR Cas12a, an enzyme that exhibits endonuclease activity upon binding to a specific sequence of DNA, to detect viral DNA from clinical samples or cDNA. We chose an electrochemical − readout to detect Cas12a trans -cleavage activity rather than a fluorescent ,− or colorimetric − readout; electrochemical readout is favorable for point-of-care applications in LRS due to its sensitivity, low cost, and direct transduction to easily quantifiable electric signals via portable and easy-to-use electrochemical hardware. , …”

“…We chose an electrochemical 28−33 readout to detect Cas12a trans-cleavage activity rather than a fluorescent 27,34−39 or colorimetric 34−37 readout; electrochemical readout is favorable for point-of-care applications in LRS due to its sensitivity, low cost, and direct transduction to easily quantifiable electric signals via portable and easy-to-use electrochemical hardware. 40,41 Specific Detection of HIV, HPV 16, and HPV 18 via Electrochemical Detection of Cas12a Endonuclease Activity. Gold leaf electrodes were fabricated (Figure 1), and their surface topography was characterized using optical profilometry (Figure S9a) and cyclic voltammetry (Figure S9b,c).…”

Iron oxide xerogels for improved water quality monitoring of arsenic(iii) in resource-limited environmentsviasolid-phase extraction, preservation, storage, transportation, and analysis of trace contaminants (SEPSTAT)

“…Additional areas for future work include investigation of adsorption and recovery kinetics in order to fully develop protocols for use during water monitoring; 14 investigation of adsorption and recovery for sample matrices incorporating organic matter; 27,[53][54][55] development of compact devices for adsorption, transportation, and recovery; 14 and stakeholder engagement in order to better understand use cases and design priorities for implementation of the SEPSTAT paradigm. 56…”