Near-field communication (NFC) labeling technology has been recently used to endow smartphones with nonline-of-sight sensing functions to improve the environment, human health, and quality of life. For applications in detecting food spoilage, the development of a sensor with high enough sensitivity to act as a switch for an NFC tag remains a challenge. In this Letter, we developed a nanostructured conductive polymer-based gas sensor with high sensitivity of ΔR/R₀ = 225% toward 5 ppm ammonia NH₃ and unprecedented sensitivities of 46% and 17% toward 5 ppm putrescine and cadaverine, respectively. The gas sensor plays a critical role as a sensitive switch in the circuit of the NFC tag and enables a smartphone to readout meat spoilage when the concentration of biogenic amines is over a preset threshold. We envision the broad potential use of such intelligent sensing for food status monitoring applications in daily life, storage and supply chains.

中文翻译：

---

用于食物腐败检测的高灵敏度，可打印的纳米结构导电聚合物无线传感器

近来，近场通信（NFC）标签技术已被用于赋予智能手机非视距传感功能，以改善环境，人类健康和生活质量。对于用于检测食物变质的应用，开发具有足够高的灵敏度以用作NFC标签的开关的传感器仍然是一个挑战。在这封信中，我们开发了一种基于纳米结构的导电聚合物基气体传感器，对5 ppm氨NH ₃具有高灵敏度ΔR / R ₀ = 225％对5 ppm的腐胺和尸胺分别具有46％和17％的前所未有的灵敏度。气体传感器在NFC标签电路中作为敏感开关起着至关重要的作用，并且当生物胺的浓度超过预设阈值时，智能手机就能读取肉类变质。我们预想将这种智能传感技术广泛应用于日常生活，存储和供应链中的食品状态监控应用中。