A smartphone-based point-of-care test for detection of Chlamydia trachomatis

DESCRIPTION provided by applicant Significance The ultimate goal of this project is a CE marked FDA cleared and CLIA waived rapid andlt min smartphone based point of care POC test to aid the diagnosis of Chlamydia trachomatis CT infections CT infections are the most common bacterial STI with almost million new cases in the US each year and associated costs exceeding $ billion Untreated women mostly in the age group are at a high risk of serious sequelae including pelvic inflammatory disease ectopic pregnancy and infertility CT infections are curable with a single pill but the fact that they are asymptomatic in up to out o infected men and women necessitates screening of high risk populations using accurate testing methods Currently used Nucleic Acid Amplification Techniques NAATs are expensive and have a significant delay between specimen collection and result severely limiting their applicability in disproportionately affected resource poor settings Rapid POC tests can prevent sequelae and curb disease transmission by enabling a same day andquot test and treatandquot approach and immediate partner notification Current POC tests for CT based on the lateral flow test LFT and using colloidal gold as reporters are andgt specific but have low clinical sensitivities down to due to their poor high limit of detection LOD In this project Luminosticsandapos proprietary andquot nanophosphorsandquot silica encapsulated persistent luminescence nanoparticles will be used as LFT reporters in an immunoassay for Chlamydial LPS cLPS Upon assay completion andlt min the disposable LFT cartridge will be readout by a smartphone using an inexpensive phone case like attachment and software app making it extremely field deployable and attractive for home testing Hypothesis We hypothesize that the improved LOD of nanophosphor LFTs expected to be to fold lower than colloidal gold LFTs will result in clinical sensitivities approaching NAATs which are andgt sensitive Preliminary results Using the same affinity reagents a fold improvement in analytical sensitivity of nanophosphor LFTs over colloidal gold LFTs has been demonstrated using unoptimized and polydisperse nanophosphors as has the feasibility of highly sensitive luminescence detection using an iPhone Specific Aims The Phase I deliverable of this project will be an analytically and clinicaly validated device prototype In Aim nanophosphor LFT parameters and smartphone components will be optimized for sensitive CT detection In Aim the performance of the optimized device prototype will be evaluated through analytical sensitivity specificity and interference studies and through a small scale retrospective clinical study The success of this Phase I project the odds of which are maximized by collaborations with or the technical services of surface chemistry STI LFT and cLPS experts will set the stage for device integration and prospective clinical testing of the new POC test for CT in Phase II It will also validate nanophosphor LFTs as a platform technology for ultrasensitive analyte detection with potential applications in a variety of critical medical conditions that need more sensitive POC tests PUBLIC HEALTH RELEVANCE The lack of a sensitive inexpensive and field deployable point of care POC test for Chlamydia represents a significant obstacle to managing the public health burden of this Sexually Transmitted Infection STI which if untreated can have disastrous consequences including infertility and an increased risk of HIV transmission The opportunistic screening of high risk populations defined by age race social behavior using highly sensitive POC tests presents the best chance of reducing its prevalence In this Phase I project Luminostics will develop a prototype of a rapid smartphone based POC test for Chlamydia designed to give physicians or minimally trained healthcare workers an unambiguous andquot positiveandquot or andquot negativeandquot result from non invasive samples in less than minutes Upon validation our POC test which by virtue of being smartphone based is more amenable to widespread adoption will enhance screening coverage to currently underserved populations and enable the immediate treatment of positive results