The dynamics of capillary flow in an open-channel system featuring trigger valves.

Trigger valves are fundamental features in capillary-driven microfluidic systems that stop fluid at an abrupt geometric expansion and release fluid when there is flow in an orthogonal channel connected to the valve. The concept was originally demonstrated in closed-channel capillary circuits. We show here that trigger valves can be successfully implemented in open channels.

Rapid enzymatic assay for antiretroviral drug monitoring using CRISPR-Cas12a enabled readout.

Maintaining efficacy of human immunodeficiency virus (HIV) medications is challenging among children because of dosing difficulties, the limited number of approved drugs, and low rates of medication adherence. Drug level feedback (DLF) can support dose optimization and timely interventions to prevent treatment failure, but current tests are heavily instrumented and centralized. We developed the REverse-transcriptase ACTivity-crispR (REACTR) assay for rapid measurement of HIV drugs based on the extent of DNA synthesis by HIV reverse transcriptase.

Democratizing Access to Microfluidics: Rapid Prototyping of Open Microchannels with Low-Cost LCD 3D Printers.

Microfluidics offer user-friendly liquid handling for a range of biochemical applications. 3D printing microfluidics is rapid and cost-effective compared to conventional cleanroom fabrication. Typically, microfluidics are 3D printed using digital light projection (DLP) stereolithography (SLA), but many models in use are expensive (≥$10,000 USD), limiting widespread use.

Integration of Group A Streptococcus Rapid Tests with the Open Fluidic CandyCollect Device.

The CandyCollect device is a lollipop-inspired open fluidic oral sampling device designed to provide a comfortable user sampling experience. We demonstrate that the CandyCollect device can be coupled with a rapid antigen detection test (RADT) kit designed for Group A Streptococcus (GAS). Through experiments with pooled saliva spiked with we tested various reagents and elution volumes to optimize the RADT readout from CandyCollect device samples.

PSA, an outdated biomarker for prostate cancer: In search of a more specific biomarker, citrate takes the spotlight.

The prevailing biomarker employed for prostate cancer (PCa) screening and diagnosis is the prostate-specific antigen (PSA). Despite excellent sensitivity, PSA lacks specificity, leading to false positives, unnecessary biopsies and overdiagnosis. Consequently, PSA is increasingly less used by clinicians, thus underscoring the imperative for the identification of new biomarkers.

Sensitive Pathogen Detection and Drug Resistance Characterization Using Pathogen-Derived Enzyme Activity Amplified by LAMP or CRISPR-Cas.

Pathogens encapsulate or encode their own suite of enzymes to facilitate replication in the host. The pathogen-derived enzymes possess specialized activities that are essential for pathogen replication and have naturally been candidates for drug targets. Phenotypic assays detecting the activities of pathogen-derived enzymes and characterizing their inhibition under drugs offer an opportunity for pathogen detection, drug resistance testing for individual patients, and as a research tool for new drug development.

REverSe TRanscrIptase chain termination (RESTRICT) for selective measurement of nucleotide analogs used in HIV care and prevention.

Sufficient drug concentrations are required for efficacy of antiretroviral drugs used in HIV care and prevention. Measurement of nucleotide analogs, included in most HIV medication regimens, enables monitoring of short- and long-term adherence and the risk of treatment failure. The REverSe TRanscrIptase Chain Termination (RESTRICT) assay rapidly infers the concentration of intracellular nucleotide analogs based on the inhibition of DNA synthesis by HIV reverse transcriptase enzyme.

Microfluidic chain reaction of structurally programmed capillary flow events.

Chain reactions, characterized by initiation, propagation and termination, are stochastic at microscopic scales and underlie vital chemical (for example, combustion engines), nuclear and biotechnological (for example, polymerase chain reaction) applications. At macroscopic scales, chain reactions are deterministic and limited to applications for entertainment and art such as falling dominoes and Rube Goldberg machines. On the other hand, the microfluidic lab-on-a-chip (also called a micro-total analysis system) was visualized as an integrated chip, akin to microelectronic integrated circuits, yet in practice remains dependent on cumbersome peripherals, connections and a computer for automation.

Pandemic-Related Instructor Talk: How New Instructors Supported Students at the Onset of the COVID-19 Pandemic.

At the same time that COVID-19 cases in the United States first began to increase, fellows in a mentored teaching apprenticeship for postdoctoral scientists began to teach undergraduate seminars. The fellows suddenly needed to support students emotionally and switch to online instruction. They were encouraged to acknowledge and address the pandemic during each class and decided to do so.

Pilot evaluation of an enzymatic assay for rapid measurement of antiretroviral drug concentrations.

Objective: Maintaining adequate drug adherence is crucial to ensure the HIV prevention benefits of pre-exposure prophylaxis (PrEP). We developed an enzymatic assay for rapidly measuring tenofovir-diphosphate (TFV-DP) concentrations-a metabolite that indicates long-term PrEP adherence.

Setting: The study was conducted at the Madison HIV Clinic at Harborview Medical Center in Seattle.

Point-of-care and Near Real-time Testing for Antiretroviral Adherence Monitoring to HIV Treatment and Prevention.

Purpose Of Review: In this report, we review the need for point-of-care (POC) or near real-time testing for antiretrovirals, progress in the field, evidence for guiding implementation of these tests globally, and future directions in objective antiretroviral therapy (ART) or pre-exposure prophylaxis (PrEP) adherence monitoring.

Recent Findings: Two cornerstones to end the HIV/AIDS pandemic are ART, which provides individual clinical benefits and eliminates forward transmission, and PrEP, which prevents HIV acquisition with high effectiveness. Maximizing the individual and public health benefits of these powerful biomedical tools requires high and sustained antiretroviral adherence.

Capillary microfluidics in microchannels: from microfluidic networks to capillaric circuits.

Microfluidics offer economy of reagents, rapid liquid delivery, and potential for automation of many reactions, but often require peripheral equipment for flow control. Capillary microfluidics can deliver liquids in a pre-programmed manner without peripheral equipment by exploiting surface tension effects encoded by the geometry and surface chemistry of a microchannel. Here, we review the history and progress of microchannel-based capillary microfluidics spanning over three decades.

Microfluidic Capillaric Circuit for Rapid and Facile Bacteria Detection.

Urinary tract infections (UTI) are one of the most common bacterial infections and would greatly benefit from a rapid point-of-care diagnostic test. Although significant progress has been made in developing microfluidic systems for nucleic acid and whole bacteria immunoassay tests, their practical application is limited by complex protocols, bulky peripherals, and slow operation. Here we present a microfluidic capillaric circuit (CC) optimized for rapid and automated detection of bacteria in urine.