[Optical oxygen sensor based on a sol-gel encapsulation method].
OBJECTIVE: To develop oxygen sensor by use of sol-gel encapsulation method and optical fiber technology. Method Organically modified sol-gel film was prepared by hydrolyzing tetraethoxysilane (TEOS) and methyltriethoxysilane (MTEOS) together, and film-processing conditions were optimized. Overall validation of the method was carried out by building Stern-Volmer plots and determining the concentration of oxygen in samples. RESULTS: The optical fiber oxygen sensor was linear in a wide range (oxygen gas: 0%-100% and dissolved oxygen: 0.55 mg/L-33.1 mg/L 29 degrees C, r > 0.9990) and had a fast response time (T95 < 20 second). Signals were steady and not easily interfered. The results of measuring oxygen in samples by using the oxygen sensor and iodimetry respectively were compared and no significant difference was found. CONCLUSION: The sensor system is applicable to continuous measurement of gas phase oxygen and dissolved oxygen on line in a complex rigorous conditions.