Naked-Eye Detection of Ethylene Using Thiol-Functionalized Polydiacetylene-Based Flexible Sensors

Abstract

Ethylene is a hormone that plays a critical role in many phases of plant growth and fruit ripening. Currently, detection of ethylene heavily relies on sophisticated and timeconsuming conventional assays such as chromatography, spectroscopy, and electrochemical methods. Herein, we develop a polydiacetylene-based sensor for the detection of ethylene via color change. The sensors are prepared through the reaction between polydiacetylene and Lawesson's reagent that results in decorating polydiacetylene with terminal thiol groups. Upon exposure to ethylene, the sensor changes color from blue to red which is visible to the naked eye. Our device shows a limit of detection for ethylene at 600 ppm in air and can be applied for monitoring ethylene released during the fruit-ripening process. Such easy-to-use ethylene sensors may find applications in plant biology, agriculture, and food industry.

Large‐Scale Sub‐1‐nm Random Gaps Approaching the Quantum Upper Limit for Quantitative Chemical Sensing

“…As shown in Figure S10, Supporting Information, we performed the mapping using the excitation laser of 785 nm over a 180 µm × 180 µm area and obtained the RSD of 3.3% for the BPE sample, better than the R6G sample (i.e., 4.4%), validating the prediction of the chemical binding. On the other hand, it has been reported that introducing thiol groups to existing molecules or using thiol molecules as a bridge to connect molecules with sensing chips [ 82–84 ] can improve the sensing performance of non‐thiol‐based molecules. These emerging strategies are promising to expand the impact of the proposed nanogap sensing architectures.…”

Food Sensors: Challenges and Opportunities

“…Drawing inspiration from biological olfactory systems, many food sensors have been designed for inclusion into packaging and processing to indicate food quality by monitoring gas composition. Common markers for gas‐targeting food sensors include carbon dioxide, [ 31,43 ] oxygen, [ 44–48 ] volatile organic compounds (VOCs), [ 49–52 ] and biogenic amines (BAs). [ 21,53–56 ]…”

“…Recently, we presented an adaption of our meat sensing technology to monitor fruit ripening. [ 51 ] PDA vesicles were functionalized to detect ethylene (LOD = 600 ppm) by substituting the carboxylic acid head group of PDA with a thiol functional group. Ethylene reacts with the thiol head group of the PDA and forms thiolene, which changes the degree of conjugation in the PDA membrane and results in a blue to red color change.…”

An Electrochemical Amperometric Ethylene Sensor with Solid Polymer Electrolyte Based on Ionic Liquid

“…Ethylene sensors based on chemoresistive [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18], optical (NDIR) [19][20][21][22], colorimetric [23][24][25], luminescence [26], fluorescence [27], piezoelectric [28][29][30], and electrochemical [31][32][33][34] principles have been developed. Each such principle has its own advantages and limitations, the comparison of which can be found in several review articles [35][36][37][38].…”