ABSTRACT
Mechanical ventilators and high-flow machines are medical devices with important measuring instruments for monitoring patients with respiratory failure. The most common monitoring parameters are lung proximal pressure, inspiratory flow, expiratory flow, inspiratory oxygen fraction, etc. The present work delves into the design, fabrication, and experimental measurement of a proximal flow sensor based on the theory of capillary tubes and stereolithography. The design was carried out in Inventor Professional 2020 software and then the computational study by CFD ANSYS to compare the dynamic pressure states of the geometric measurement points. The manufacturing was carried out using SLA 3D printing technology on an ANYCUBIC FHOTON MONO X.The fabricated FM SLA prototype has radially positioned latex tubing lines to achieve differential pressure measurement at two points separated by capillary tubes. These hoses are connected to a developmental embedded system based on a HONEYWELL 001PG7A5 differential pressure sensor and Arduino Uno Microcontroller. Finally, experimental tests of the Flow Meter Stereolithography (FM SLA) protype measurements were performed with flow rates from 0 to 44.5 lpm in 1 lpm increments. From the collected data we have an R2: 0.9983 in quadratic polynomial approximation with the actual measurement data. © 2022 IEEE.
ABSTRACT
As the COVID-19 pandemic continues, there remains a need for fast, accurate and low-cost diagnostic tests to prevent outbreaks. We have developed an electrochemical capillary-flow driven immunoassay (eCaDI) capable of detecting SARS-CoV-2 nucleocapsid (N) protein in self-administered nasal samples at the point of care (POC). The low-cost device is made of polyester and adhesive films and provides sequential delivery of sample and reagents to a detection zone integrating a screen-printed carbon electrode (SPCE) modified with anti-N protein antibodies from a single addition of sample, automating the steps of an ELISA. The modified electrodes are highly sensitive and selective for COVID-19 N protein and were successfully applied to test clinical samples. The novelty of this work resides in the integration of sensitive electrochemical detection with pump-free capillary-flow assay, providing accuracy at the POC. Previously reported systems are slow and/or require multiple user steps reducing the utility for POC applications relative to the system reported here. © 2021 MicroTAS 2021 - 25th International Conference on Miniaturized Systems for Chemistry and Life Sciences. All rights reserved.