PVB-联吡啶钌氧敏感膜荧光光度法对非水溶剂中微量溶解氧的测定

PVB-Bipyridylruthenium(Ⅱ) Oxygen Sensor for the Determination of Trace Amount of Dissolved Oxygen in Non-aqueous Solvents with Spectrofluorimetry

摘要：以聚乙烯醇缩丁醛（PVB）为共聚前驱体，联吡啶钌（[Ru（bpy）3]Cl2·6H：O）为氧荧光指示剂，制备了一种新型氧敏感膜，据此建立了采用流动注射荧光光度法测定非水溶剂中微量溶解氧的新方法。在涂膜液中联吡啶钌浓度为1mmol／L，涂膜液用量为2．5mL，20℃下放置24h，40℃恒温干燥48h时，制备的氧敏感膜（膜厚0．5mm）对氧响应的灵敏度最高。当激发波长为465nm，溶液流速为1．0mL／min时，该敏感膜对氧有较快的响应时问、良好的响应可逆性、较好的稳定性。对1，2-丙二醇和PEG-400中溶解氧的测定结果表明，两者的Stern—Volmer曲线的线性范围分别为0～69．12mg／L和0～109．54mg／L，检出限分别为4．25mg／L和0．56mg／L，RSD（n=6）分别为2．0％和1．8％。

A sensitive flow injection spectrofluorimetric analysis method was developed for the determination of trace amount of dissolved oxygen in non-aqueous solvents. A new prepared oxygen-sensitive film with polyvinyl butyral （PVB） was used as precursor and tris （2, 2＇-bipyridyl）ruthenium （Ⅱ ） dichloride hexahydrate[ Ru（bpy） 3 ] Cl2 · 6H2O] as fluorescence indicator. The oxygen-sensitive film preparation parameters and the oxygen determination conditions were thoroughly studied. The results indicated that the prepared oxygen-sensitive film with thickness of about 0. 5 mm showed the highest sensitivity to oxygen when it was prepared by 2.5 mL 1 mmol/L [ Ru（bpy） 3 ] Cl2 · 6H2O solution as preeursor at 20 ℃ for 24 h and then dried at 40 ℃ for 48 h. The optimum determination conditions were as follows ： excite wavelength ： 465 nm ; flow rate ： 1.0 mL/min ; temperature ： 25 %. Under the optimal conditions, the response time of the prepared oxygen-sensitive film to oxygen was less than 30 s and the relative standard deviations （RSDs） of fluorescence intensity were 2.4% and 4.4% for nitrogen saturated solution and oxygen saturated solution, respectively. The oxygensensitive film has excellent reversibility to dissolved oxygen, and could keep stable at least 120 d. The proposed method was applied to determine the concentration of dissolved oxygen in propylene glyeol and PEG - 400. The experimental results showed that the linearity of the Stern - Volmer plots were 0 -69.12 rng/L for propylene glycol and 0 - 109.54 mg/L for PEG -400. Their detection limits were 4.25 mg/L and 0.56 mg/L, with RSDs（n =6） of 2.0% and 1.8% , respectively.