A 3D-Printed Breath Analyzer Incorporating CeO₂ Nanoparticles for Colorimetric Enzyme-Based Ethanol Sensing

Abstract

Breath biosensors are a viable cost-effective platform for ethanol detection providing features such as portability, simplicity, and real-time in situ analysis. Herein, we describe a custom-made 3D-printed device containing a nanoparticle-based enzyme biosensor, designed to allow the user to blow breath on the sensor surface and obtain an immediate measure of the alcohol level in breath. The entire assembly enables sample collection, analysis, and signal generation, which could be visualized by the naked eye or by image capturing with a smart phone for color measurement. The biosensor unit was fabricated onto paper that was modified with alcohol oxidase (ALOx) enzyme and cerium oxide nanoparticles (CeNPs), used as a combined peroxidase-like mimetic and chromogenic reagent. The enzymelike chromogenic behavior of the nanoparticles facilitates production of a robust biosensor with all the reagents integrated within the sensing body. Because the biosensor uses biomimetic nanoparticles in lieu of peroxidase enzymes and soluble redox reagents, the detection system has increased stability and low cost. The biosensor showed a linear range of 0.02−1.2% (0.2−1.2 g/L) and a limit of detection of 0.001% and was able to measure breath ethanol concentrations at levels comparable to electronic breathalyzers, at a low cost and with high sensitivity. The device is sensitive, selective, portable, and simple to operate and can be used broadly for ethanol detection in multiple applications, in law enforcement, forensics, and food and beverage authentication. The method is inexpensive, and the 3D device and the biosensor can be mass-produced, which provides a route to extend this technology for noninvasive monitoring of other volatile compounds in breath for disease diagnostics and other applications.

Glucose and Ethanol Detection with an Affinity-Switchable Lateral Flow Assay

“…To further demonstrate the versatility and applications of Au@H 2 O 2 -ASB in the ASLFA method, we proceeded to use Au@H 2 O 2 -ASB for the detection of ethanol in blood serum by using alcohol oxidase (AO), which can catalyze the oxidation of primary alcohols to generate aldehydes and H 2 O 2 . Although several colorimetric ethanol detection methods have been reported previously, there are no reports of ethanol detection by using the LFA method due to the challenge of producing a high-affinity antibody for the small molecule ethanol. − To demonstrate that ethanol can be analyzed rapidly by our ASLFA method, we incubated Au@H 2 O 2 -ASB with 5 mM ethanol and 10 μg/mL AO in undiluted FBS at 37 °C for 30 min. Then, the SA-immobilized test trips were dipped into the FBS reaction mixture to identify the test line.…”

Sensors in the Detection of Abused Substances in Forensic Contexts: A Comprehensive Review

“…In Mustafa et al [55], colorimetric strips were employed within an optical sensor configuration, utilizing Cerium nanoparticles (CeNPs) as the matrix in conjunction with the enzyme alcohol oxidase (ALOx). This combination served for the collection, analysis, and generation of a signal that can be discerned with the naked eye [55].…”

Noninvasive Colorimetric Detection of Acetic Acid in Human Breath Based on an Alginate/Ni–Al-LDH/Dye Composite Film

“…Colorimetric methods have attracted the attention of researchers as an alternative approach . The main problem of colorimetric methods is the environmental influence on the quality of the results . For example, breath colorimetric sensors may report an incorrect response when affected by humidity.…”

“… 11 The main problem of colorimetric methods is the environmental influence on the quality of the results. 12 For example, breath colorimetric sensors may report an incorrect response when affected by humidity. Therefore, it is necessary to create a structure with the least influence and higher selectivity for important breath markers.…”