The characterization of volatile organic compounds (VOCs) plays a crucial role in environmental diagnostics, biomedical and food science. For example, microbial reactions between microorganisms and food can produce various VOC biomarkers, paving the way for promising methods to quantify food freshness. Triethylamine (TEA) is one of the most representative biomarkers, and its concentration increases as protein degradation progresses during meat spoilage. However, achieving high-sensitivity real-time monitoring of TEA remains a huge challenge, limiting personalized food freshness recognition.

Although various technologies such as gas chromatography-mass spectrometry (GC-MS) and optical equipment can provide accurate VOC detection, they are considered expensive, non portable, time-consuming, and require specialized operational skills, limiting their use as personalized measurement tools. In order to achieve portable VOC detection, various detection technologies have been developed, such as acoustic type, chemical resistance type, and colorimetric type. Especially, chemical resistance sensor devices have the advantages of high sensitivity, low cost, simple operation, simple structure and manufacturing process, which have aroused great interest among researchers. The most widely studied chemical resistance TEA sensor is based on metal oxides, which detect TEA through resistance changes through the oxidation-reduction reaction

between chemical analytes and active oxygen species in metal oxides. However, in order to improve sensitivity, metal oxide based sensors require a heating process (>240 ° C) to enhance the adsorption charge transfer kinetics. This strategy may be affected by increased configuration complexity, additional energy consumption, unpleasant selectivity, and significant baseline drift. In addition, the heating process also leads to grain growth of the sensing material, reducing the stability and lifespan of the device. Therefore, these drawbacks make it difficult to integrate metal oxide based chemical resistance sensors into portable systems. Despite the emergence of room temperature (RT) VOC sensors, their sensitivity and response/recovery characteristics are often limited due to weak reaction energy and low conductivity modulation between analytes and sensing materials. The detection limit of the RT TEA sensor previously reported was higher than 2 parts per million (ppm). Therefore, rapid detection of volatile organic compounds at one billionth (ppb) levels at room temperature is still not feasible.

Recently, LC (Inductive Capacitive) wireless sensors have shown great potential in real-time sensing in the fields of healthcare and environmental governance. This type of sensor can simultaneously perform multiple functions including signal processing and transduction, thereby achieving efficient real-time chemical sensing. However, due to the inherent principles and high noise of LC sensors, the sensing signals of low concentration chemical analytes are difficult to detect, which limits their practical applications. The traditional adsorption charge transfer kinetics engineering of gas sensitive materials for chemical analytes faces a trade-off between sensitivity and recovery time, which has been common in previous research on gas sensitive materials. It is worth noting that LC wireless sensors have multiple transmission characteristics, such as resistance and capacitance, which can simultaneously affect the device's return loss (S11). Therefore, this may imply a promising approach to enhance the response to VOC

analytes by combining the response of multiple sensing parameters of LC wireless sensors. At the same time, this also represents a new strategy that can simultaneously perform multiple conversion processes without sacrificing recovery kinetics, thereby solving the trade-off between sensitivity and recovery, which is completely different from traditional sensitization strategies such as heterojunction synergy. However, this concept has never been validated and its implementation is influenced by two factors: (1) the effective adsorption charge transfer kinetics between the sensing material and TEA at room temperature; (2) The multiple transmission characteristics of sensing materials. Fundamentally, designing fast and highly sensitive LC sensors for VOC sensing at RT requires collaborative advancements in materials, equipment, and sensing mechanisms.