Role of Paper-Based Sensors in Fight against Cancer for the Developing World

Abstract

Cancer is one of the major killers across the globe. According to the WHO, more than 10 million people succumbed to cancer in the year 2020 alone. The early detection of cancer is key to reducing the mortality rate. In low- and medium-income countries, the screening facilities are limited due to a scarcity of resources and equipment. Paper-based microfluidics provide a platform for a low-cost, biodegradable micro-total analysis system (µTAS) that can be used for the detection of critical biomarkers for cancer screening. This work aims to review and provide a perspective on various available paper-based methods for cancer screening. The work includes an overview of paper-based sensors, the analytes that can be detected and the detection, and readout methods used.

Paper-based colorimetric sensors for point-of-care testing

“…Paper-based colorimetric sensors utilize paper as a substrate, leveraging its unique properties to facilitate colorimetric reactions and visual readouts. The choice of paper material is a critical factor in the fabrication of paperbased colorimetric sensors, as different types of paper offer distinct characteristics that can signicantly impact the sensor's performance, 26,47 as shown in Table 1.…”

“…Paperbased sensors typically consist of a paper substrate, and functional indicator reagents. [26][27][28] The paper substrate serves as a solid support, providing a matrix for the deposition of reagents and facilitating uid transport through capillary action. Indicator reagents are carefully selected to undergo a color change in the presence of the target analyte.…”

Paper-based point of care diagnostics for cancer biomarkers

“…4 Over the past 5 years, a handful of review articles highlighted the importance of low-cost paper-based diagnostics in cancer detection with individual focus on either type of paper-based diagnostics, microfluidic-based analytical devices, or the role of nanomaterials in cancer detection, however, a systemic and comprehensive review highlighting the advancements at all the fronts of paperbased cancer detection is highly desirable to drive the research in this domain. [6][7][8][9][10][11] This review exhaustively highlights the impactful technological advancements that occurred over the past decade at each step of biomarker detection starting from advancements in paper substrate chemistry, assay type, and detection technique, to advanced signal enhancement strategies exploited in developing extremely sensitive paperbased biosensors specifically for cancer detection. In assay type, this review comprises conventional dipstick assays to advanced 3D μPADs (microfluidic paper-based analytical devices), wherein the detection techniques comprise dot blot, advanced immunochromatography integrated with nucleic acid amplification technique, molecularly imprinted polymers, and conducting papers.…”

“…4 Over the past 5 years, a handful of review articles highlighted the importance of low-cost paper-based diagnostics in cancer detection with individual focus on either type of paper-based diagnostics, microfluidic-based analytical devices, or the role of nanomaterials in cancer detection, however, a systemic and comprehensive review highlighting the advancements at all the fronts of paper-based cancer detection is highly desirable to drive the research in this domain. 6–11…”

Nanotechnology-Based Diagnostics for Diseases Prevalent in Developing Countries: Current Advances in Point-of-Care Tests

“…In 2022, Dukle et al reported advances on the development of paper-based sensors that can be applicable in cancer screening, especially in low-income countries. The review highlighted the types of paper-based sensors, the analytes that can be detected, and the detection and readout methods, with an emphasis on the need for low-cost, portable devices that should not require any special training [ 3 ]. During the same year, Yang et al detailed microfluidic POC equipment and its applications in detecting infectious diseases, cardiovascular diseases, cancer, and chronic diseases.…”