Using a Paper-Based Analytical Device Designed for Remote Learning Environments to Achieve Simple Quantitative Colorimetry without Micropipettes

Abstract

The majority of chemical experiments conducted during educational programs are carried out in laboratories because they require instructors with special skills, in addition to large, expensive instruments. Recently, there has been an increasing demand for chemical experiments that can be carried out anywhere. Herein, we propose a novel type of paper-based analytical device (PAD) for enabling quantitative analysis without the requirement for a micropipette, since the PAD features a large sample loading zone and a waste zone, enabling accurate volume control of a liquid sample. We initially employed a micropipette to evaluate the PAD and demonstrate the quantitative analysis of ascorbic acid (AA) and pH using different loading volumes. Finally, we determined the AA concentrations and pH values of commercially available beverages using disposable plastic droppers, and the obtained results were in good agreement with those obtained through conventional methods. This PAD format can therefore be used as a novel educational tool for conducting certain chemical analyses in remote learning environments.

Paper based microfluidic devices: a review of fabrication techniques and applications

“…Antibody screening tool that shows whether a patient has a contagious disease infection and an immune reaction to it [196] Medical diagnosis Devices used to identify uropathogenic E. coli rely on the ability to detect nitrite, which is produced when E. coli reduces nitrate. [197] Food quality control Pesticide detection sensor made of paper for crop samples [198] Food quality control 3D PAD for identifying the milk allergen casein [199] Food quality control Colorimetric PAD to detect Salmonella [200] Medical diagnosis A pop-up, DNA-based, label-free ePAD for HBV (a biomarker of liver disorders) detection [201] Medical diagnosis A vertical flow-based paper sandwich-type immunosensor for sensing of influenza H1N1 viruses [202] Food quality control Instrument to measure aluminium in water without pre-treatment or pre-concentration of the sample [203] Medical diagnosis PAD for detection of malaria [204] Medical diagnosis Device for medical diagnosis and sweat analysis that simultaneously measures glucose, lactate, pH, chloride, and volume [205] Medical diagnosis Platform for electrochemical immunosensing for pmol/L Ebola virus detection [206] Medical diagnosis Human chorionic gonadotropin (a pregnancy indicator) detection via a PAD [207] Medical diagnosis PAD to immobilize different antibodies or anti-immunoglobulin E onto screen-printed carbon electrodes [208] Medical diagnosis PAD for COVID-19 diagnosis [209][210][211] Medical diagnosis Biosensor for POC sensing of dengue virus [212] Food quality control PAD to track total ammonia in fish pond water [213] Medical Diagnosis Electrochemical and self-powered paper-based device for glucose sensing [214,215] Medical diagnosis PAD for eliminating the necessity for a micropipette in quantitative analysis [216] Medical diagnosis PAD to extract blood plasma from a whole blood sample [138] Medical diagnosis A disposable ePAD for quantification of albumin in a urine sample [217] Food quality control 3D PAD to simultaneously detect multiple chemical adulterants in milk [195,218] Medical diagnosis An intelligent paper-based UV monitor that can detect the solar UV intensity in real time for human health and safety…”

At-Home Microscale Paper-Based Quantitative Analysis Activity with External Standards

“…In addition to consuming smaller quantities of reagents, microscale experiments also generate less waste and are inherently safer than their conventional-scale counterparts . While microscale experiments typically require specialized equipment that would not be suitable for an at-home kit (e.g., micropipettes), microfluidic paper-based analytical devices (microPADs) provide a platform for simple and inexpensive microscale analysis. , MicroPADs originated as low-cost alternatives to conventional microfluidic devices for the development of point-of-care diagnostics. , More recently, microPADs have found applications in the classroom, and several experiments involving microPADs have been described. − Since microPADs are small and lightweight and can be distributed easily, they are also ideal for at-home activities.…”

Students’ Attitudes on Remote-Flexible Instrumental Analysis Laboratory Experiments During COVID-19

“…Fortunately, many instructors rose to the occasion. As a result, there are now several reports of quality, low-resource remote analytical laboratory experiments, including the use of analytical laboratory kits, 1,2 paper-based microanalytical devices, 3,4 and spectroscopic experiments with smartphone cameras. 5−8 Now, looking ahead to postpandemic times, it is necessary to evaluate the role of these remote experiments to learn how they can be used in future analytical chemistry laboratory courses.…”

“…Fortunately, many instructors rose to the occasion. As a result, there are now several reports of quality, low-resource remote analytical laboratory experiments, including the use of analytical laboratory kits, , paper-based microanalytical devices, , and spectroscopic experiments with smartphone cameras. − Now, looking ahead to postpandemic times, it is necessary to evaluate the role of these remote experiments to learn how they can be used in future analytical chemistry laboratory courses. Toward that end, here we describe the implementation and assessment of two remote-flexible learning experiments designed for Instrumental Analysis Laboratory at Creighton University in Fall 2020 and Fall 2021 and their potential for inclusion in a postpandemic curriculum.…”