Highly sensitive and linear calibration optical fiber oxygen sensor based on Pt(II) complex embedded in sol–gel matrix

Portable optical oxygen sensor based on time-resolved fluorescence

“…Table 1 compares the performance characteristics of the proposed Pt(II)-doped oxygen sensors with those of representative quenchometric O 2 sensors presented in other literature comprising PtTFPP dye embedded in various support matrices. Comparing the performance of the various sensors, it is apparent that sensors using a Pt(II) complex embedded in the solgel matrix [8][9][10][11]25] have a significantly higher sensitivity than those using polymer [26][27][28][29][30] as the support matrix. This is because the organically modified silicate (ORMOSIL) matrix improves the response and sensitivity of the platinum-(II)-complex-based oxygen sensors due to their porous structure, which enhances their ability to accommodate and disperse analyte-sensitive dyes.…”

“…Although the lifetimes are extended compared to organic dyes, the fluorescent lifetimes of these complexes are still not long enough for measurement of low oxygen concentrations. Therefore, the third generation of optical oxygen sensing materials with longer lifetimes, e.g., Pt(II) and Pd(II) complexes have been developed [8][9][10][11][12][13]. The typical lifetimes of these optical oxygen sensing materials are in the range of 20-100 μs, or even longer.…”

“…The fluorescent intensity or lifetimes of optical oxygen sensing materials are the two principal signal transductions used in optical fluorescence oxygen sensors. Monitoring the emission intensity of the oxygen sensing materials versus different oxygen concentrations is a straightforward approach [8][9][10][11][12][13]. However, intensity-based oxygen sensors can suffer interference from various factors, such as power drifting of the light source, turbidity of the gas sample, background or auto fluorescence of the samples as well as photobleaching of the fluorescent dye itself.…”

Indicators for optical oxygen sensors

“…The higher photostability of 32 compared to 30 is explained by the electron-withdrawing character of the perfluorophenyl substituents which reduces the electron density on the porphyrin ring thus rendering the PtTFPP less reactive toward oxidation by singlet oxygen [134]. PtTFPP possesses similarly long decay time (60 μs) and acceptable brightness when excited in the visible rage; it has been widely used as oxygen indicator in different types of matrices such as polystyrene [5,134], fluoroacrylic polymer as a component of a pressure-sensitive paint [51,186], in sol-gel [44,45], poly(norobornene)s [213], and many other matrices. PtTFPP was also modified to be able to be polymerized and cross-linked with hydrophilic poly(2-hydroxyethyl methacrylate)-co-polyacrylamide or hydrophobic polystyrene to generate highly photostable and biocompatible sensing films [216].…”

Optical and Electrochemical Combination Sensor with Poly‐Aniline Film Modified Gold Surface and Its Application for Dissolved Oxygen Detection

“…The widely studied method for DO measurement is Clark electrode and its modified forms [3][4][5], including the potentiometric DO sensors based on metal oxides electrodes [6][7][8]. Although electrochemical-based DO sensors can provide accurate measurement results, its drawbacks, such as the slow response time, a "static" reading and the aging of the electrodes, have limited its general application [9].Optical methods such as fiber optic sensors [10] offer attractive alternatives to the electrochemical-based DO sensors due to the fast response time, little oxygen consumption and no interference from exterior electromagnetic fields [9][10][11].Among these optical methods for DO detection, fluorescence-based and luminescencebased DO sensors have received special attention [11,12]. Such sensors exploit a decrease in fluorescence intensity of an excited indicator as a result of the quenching effect induced by the energy-transfer mechanism with oxygen molecule [12].…”