Salaris Nikolaos, Haigh Paul, Papakonstantinou Ioannis, Tiwari Manish K
Nanoengineered Systems Laboratory, UCL Mechanical Engineering, University College London, London WC1E 7JE, United Kingdom.
Wellcome/EPSRC, Centre for Interventional and Surgical Sciences (WEISS), University College London, London W1W 7TS, United Kingdom.
Sens Actuators B Chem. 2023 Jan 1;374:132794. doi: 10.1016/j.snb.2022.132794.
Absolute oxygen sensors based on quenching of phosphorescence have been the subject of numerous studies for the monitoring of biological environments. Here, we used simple fabrication techniques with readily available polymers to obtain high performance phosphorescent films. Specifically, evaporation-based phase separation and the breath figure technique were used to induce porosity. The pore sizes ranged from 37 nm to 141 m while the maximum average porosity achieved was 74%. The oxygen sensing properties were evaluated via a standarised calibration procedure with an optoelectronic setup in both transmission and reflection based configurations. When comparing non-porous and porous films, the highest improvements achieved were a factor of 7.9 in dynamic range and 7.3 in maximum sensitivity, followed by an improved linearity with a half-sensitivity point at 43% O V/V. Also, the recovery time was reduced by an order of magnitude in the high porosity film and all samples prepared were not affected by variations in the humidity of the surrounding environment. Despite the use of common polymers, the fabrication techniques employed led to the significant enhancement of oxygen sensing properties and elucidated the relation between porous film morphologies and sensing performance.
基于磷光猝灭的绝对氧传感器一直是众多用于监测生物环境研究的主题。在此，我们使用简单的制备技术和易于获得的聚合物来获得高性能的磷光薄膜。具体而言，基于蒸发的相分离和呼吸图技术被用于诱导孔隙率。孔径范围从37纳米到141微米，而实现的最大平均孔隙率为74%。通过在透射和反射配置下使用光电装置的标准化校准程序来评估氧传感特性。当比较无孔和多孔薄膜时，实现的最高改进是动态范围提高了7.9倍，最大灵敏度提高了7.3倍，随后线性度得到改善，半灵敏度点在43% O₂V/V。此外，高孔隙率薄膜的恢复时间减少了一个数量级，并且制备的所有样品不受周围环境湿度变化的影响。尽管使用了常见的聚合物，但所采用的制备技术导致氧传感特性显著增强，并阐明了多孔薄膜形态与传感性能之间的关系。
