Metal oxide‐based gas sensors for the detection of exhaled breath markers

Abstract

Exhaled breath test is a typical disease monitoring method for replacing of blood and urine samples that may create discomfort for patients. To monitor exhaled breath markers, gas biomedical sensors have undergone rapid progresses for non‐invasive and point‐of‐care diagnostic devices. Among gas sensors, metal oxide‐based biomedical gas sensors have received remarkable attentions owing to their unique properties, such as high sensitivity, simple fabrication, miniaturization, portability, and real‐time monitoring. Herein, we reviewed the recent advances in chemoresistive metal oxide‐based gas sensors with ZnO, SnO 2 , and In 2 O 3 as sensing materials for monitoring a range of exhaled breath markers (i.e., NO, H 2 , H 2 S, acetone, isoprene, and formaldehyde). We focused on the strategies that improve the sensitivity and selectivity of metal oxide‐based gas sensors. The challenges to fabricate a functional gas sensor with high sensing performance along with suggestions are outlined.

Emerging roles of cystathionine β-synthase in various forms of cancer

“…In fact, there are several studies showing that cancer patients exhale higher levels of H 2 S than healthy controls [ 394 , 401 ]. Detection methods based on this principle (“artificial noses” [ [402] , [403] , [404] ]) are in various stages of development. The exhaled breath-based approach, however, could not distinguish between H 2 S produced in the airways vs. systemically produced H 2 S which is upregulated during various inflammatory conditions [ 405 , 406 ] vs. H 2 S generated by the tumor tissue.…”

Effect of Ag Addition on the Gas-Sensing Properties of Nanostructured Resistive-Based Gas Sensors: An Overview

“…Therefore, the early detection of toxic gases using reliable electronic gas sensors is extremely important. In this respect, chemiresistive gas sensors are potentially attractive due to their easy manufacturing, simple operating principle, and low cost [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 ]. In the area of resistive-based gas sensors, different semiconducting materials can be used for the realization of gas sensors.…”

“…On the other hand, semiconducting metal oxides (SMO)-based gas sensors have advantages such as high response, high stability, relatively fast dynamics, simple fabrication, and low costs. So, they are very popular for the detection of various gases [4][5][6][7][8][9][10][11][12][13][14]. However, they work at high temperatures and show poor selectivity.…”

Approaches to Formaldehyde Measurement: From Liquid Biological Samples to Cells and Organisms

“…The third group includes genetically-encoded sensors that were developed for living cells and organisms. However, the variety of methods for FA assessment is not limited to those mentioned above: there are numerous other approaches for analysis of air samples using graphene- and metal oxide-based nanomaterial gas sensors [ 37 , 38 , 39 , 40 , 41 ], optical FA-sensors [ 42 ] and others that are out of the scope of this review.…”