Development of a Microfluidic Point-of-Care HCV Viral Load Assay

DESCRIPTION provided by applicant The Daktari diagnostic platform based on microfluidic sample processing and electrochemical detection is designed for use by a nurse or primary health care worker with minimal training total hands on time is seconds The initial Daktari CD Assay has been developed for performing CD cell counts from a L fingerstick blood sample in less than ten minutes at low cost Under this project we will develop an HCV Viral Load Assay on the Daktari platform The HCV Viral Load Assay will incorporate blood collection sample processing HCV capture and electrical detection in an integrated disposable plastic cartridge In Phase I we will establish the feasibility of whole HCV virus magnetic capture and lysis and electrical detection of released viral protein First the binding specificity and sensiivity of a selected panel of HCV capture agents will be evaluated in both plasma and whole blood In parallel we will optimize and evaluate the threshold of detection of an electrical detection method based on a sandwich immunoassay to detect released HCV core antigen using a gold nanoparticle silver deposition signal amplification cascade The electrical detection method will make use of Daktariandapos s novel electrode design Should the data from these two studies determine technical feasibility Phase II of the project will integrate blood collection HCV capture and lyss and electrical detection into a Daktari microfluidic cartridge yielding a complete HCV Viral Load Assay ready for commercial scale up for use in Daktariandapos s handheld instrument First the HCV capture protocol consisting of magnetic mixing and concentration using microparticles functionalized with the anti HCV capture agent identified in Phase I will be optimized and adapted to the Daktari cartridge production format Second the electrical detection module identified in Phase I will be integrated and the layout of the fluidic paths including reagent storage and handling will be designed and tested ultimately leading to a complete HCV Viral Load Assay cartridge Finally the current Daktari instrument will be modified to incorporate the permanent magnets required for magnetic capture of HCV virions and an additional mechanical actuator for reagent transport The final deliverable will be a simple low cost instrument capable of being used at the primary care level to quantify circulating HCV and identify patients with active HCV infection in need of treatment PUBLIC HEALTH RELEVANCE Hepatitis C is a public health crisis with as many as million people infected worldwide many of them undiagnosed Recently treatment options for hepatitis C virus HCV infection have greatly improved catalyzing interest in a global effort to control HCV Rapid tests to confirm exposure to HCV are widely available However the lack of an affordable simple to use diagnostic test that determines treatment eligibility is currently a bottleneck in this effort In this application we will develop an HCV Viral Load test to run in Daktariandapos s point of care diagnostic platform ultimately enabling roll out of HCV care to million Americans and million people worldwide