Polydiacetylene-Based Sensors To Detect Volatile Organic Compounds

Abstract

Recently, volatile organic compound (VOC) detection has broadened from conventional environmental safety and air quality monitoring to food quality control and disease diagnosis. Current VOC detection technologies are expensive, bulky, and nonintuitive. Polydiacetylenes (PDAs) as colorimetric sensors have been extensively studied owing to their unique structural and optical properties. PDA’s color changes from blue (nonfluorescent) to red (fluorescent) upon exposure to stimuli. This blue-to-red transition is visible to the naked eye, making it highly suitable for independent and rapid detection. PDA is versatile and can be fabricated in various forms including paper, thin film, and 3D scaffold. In this Perspective, we provide an overview of PDA-based systems for VOC detection. We focus not only on the performance but also on the sensor VOC testing methods (calculation and experimental setup). We then identify several aspects to improve in future research to enable cross-comparison and validation between studies. Furthermore, we also outline the key considerations for device fabrication to facilitate better translation of research to commercialization.

Materials Design Strategies for Solvent-Resistant Organic Electronics

“…We synthesized isoindigo-based oligomers with side chains containing 1,3-butadiyne end-groups to trigger a topochemical photopolymerization in the solid-state, resulting in materials covalently cross-linked through polydiacetylene, a conjugated ene-yne polymer without formation of bypoducts. − We found that, by incorporating amide groups into the side chain design, the resulting intermolecular hydrogen bonding led to favorable orientation of the butadiyne moieties for cross-linking through a 1,4-addition reaction upon exposure to UV light (Figure a). This topochemical reaction led to the formation polydiacetylene cross-links, a conjugated polymer with unique optical features that are widely used for chemical and physical sensing. − While the direct impact of the PDA cross-links on the electronic properties (charge transport) has not been demonstrated in this work, the cross-linked moieties were shown to have little effect on thin-film morphological and photophysical properties while significantly altering the solubility of the material. The distinct change in solubility of the cross-linked material was demonstrated by photopatterning with a shadow mask and subsequent washing with organic solvents.…”

Polydiacetylene-based sensors for food applications

“…This can be used to improve mechanical properties, assist in binding to the substrate, and functionalize the film to analytes like volatile organic compounds (VOCs) that interact with the matrix polymer. 8…”

“…4,5 Polydiacetylenes (PDAs) are a class of conjugated polymers with unique optical properties that can be used to build colorimetric and fluorescent sensors. [6][7][8][9] They exhibit a strong blue to red color change and a ''turn on'' fluorescence signal in response to stimuli such as heat, pressure, light, chemical and biological recognition events. 9,10 The color change can be read by the naked eye, and the sensors are versatile, low in cost, and biocompatible.…”

Recent development of the fluorescence-based detection of volatile organic compounds: a mechanistic overview

“…Moreover, both conjugated/nonconjugated polymers have been employed to develop nanoparticle systems for real-world applications including drug delivery, catalysis, sensing, and wastewater treatment. 55 Along with toxic, carcinogenic, and explosive properties, some VOCs including both saturated alkanes and benzene derivatives are the key signal molecules for lung cancer, food mildew, and rotting. [56][57][58] The detection of saturated alkanes is more challenging as they do not possess a significant tendency to extract or donate electrons, which is the commonly observed sensing mechanism.…”

“…Moreover, both conjugated/nonconjugated polymers have been employed to develop nanoparticle systems for real-world applications including drug delivery, catalysis, sensing, and wastewater treatment. 55…”