The Past, Present and Future in Tube- and Paper-Based Colorimetric Gas Detectors

Abstract

Colorimetric gas detectors have been widely applied in many fields such as environmental sciences, industrial hygiene, process control, forensic science and indoor air quality monitoring. They have a history of about 100 years and include devices such as gas detector tubes and paper-based gas detectors. The sensitivity and selectivity of the colorimetric gas detector are relatively high compared to other types of gas detectors such as semiconductor, catalytic combustion and electrochemical gas detectors. Detection of gas concentration can be performed by the naked eye in some colorimetric gas detectors. These methods do not require an electrical power source and are simple, so they are suitable for field operations. This review introduces the history and provides a general overview of the development in the research of colorimetric gas detectors. Recently, the sensitivity and selectivity of colorimetric gas detectors have improved. New materials such as enzymes or particles with a large surface area have been utilized to improve selectivity and sensitivity. Moreover, new gas detectors without toxic materials have been developed to reduce the environmental load. At present, there is a rapid development of IoT sensors in many industrial fields, which might extend the applications of colorimetric gas detectors in the near future.

Detection of alkali and alkaline earth metal ions using birefringence of hyperswollen lamellar phase

“…11 As the detection methods without electric supplies, pH-test papers and gas detector tubes have been used. [12][13][14] In these methods, we can visually observe the color change of the detector in response to the small number of targets because the probe molecules are immobilized to the substrates like lter papers and silica gels. The two-dimensional immobilization of the probe molecules can prevent signal attenuation caused by diffusion.…”

Development of a detector tube for screening tadalafil and its analogues in adulterated sexual enhancement products

“…To address these problems, a detector tube for Tds which contain silica gel powder impregnated with sulfuric acid has been previously introduced 19 . A detector tube is mainly used to detect the concentration of hazardous gases and vapors; they are portable, easy to operate, and rapid 20,21 . Furthermore, the tube developed here is both compact and portable and stands to improve safety by preventing leakage of the detecting agent via utilization of the powdered form.…”

“…19 A detector tube is mainly used to detect the concentration of hazardous gases and vapors; they are portable, easy to operate, and rapid. 20,21 Furthermore, the tube developed here is both compact and portable and stands to improve safety by preventing leakage of the detecting agent via utilization of the powdered form. In the present study, the detector tube was further validated in detail, presenting the qualitative and semiquantitative test results, as well as detector tube stability.…”

Threshold-Responsive Colorimetric Sensing System for the Continuous Monitoring of Gases

“…A plethora of colorimetric sensors have been applied to detect environmental pollutants [ 7 , 8 ], toxic agents [ 9 , 10 , 11 ], biomarkers, and pharmaceutical- and food-relevant molecules [ 12 , 13 , 14 ]. Along this line, several reviews have been published [ 15 , 16 , 17 , 18 , 19 ]. Various detection systems can provide the readout of colorimetric sensors, including simple visual color interpretations, hand-held reading devices [ 20 , 21 ], commercial spectrometers [ 22 , 23 ], custom embedded systems [ 24 , 25 ], and complementary metal-oxide semiconductor (CMOS) chips embedded in commercial cameras and smartphones [ 15 , 26 , 27 , 28 , 29 , 30 ].…”