Rivera Laia, Puyol Mar, Miltsov Serguei, Alonso Julian
Sensors and Biosensors Group, Analytical Chemistry Department, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain.
Anal Bioanal Chem. 2007 Mar;387(6):2111-9. doi: 10.1007/s00216-006-1068-z. Epub 2007 Jan 17.
New far-visible absorbing anilino-cyanine dyes have been synthesised for future application as chromoionophores in integrated waveguide absorbance optodes based on bulk optodes. The effect of the heterocycle, of the substitution of the heterocyclic nitrogen and of the type of heptamethine central ring on the pKa values (4.3-8.2 in ethanol-water solutions and 9.5-11.0 in plasticised PVC membranes), on the spectroscopic characteristics of the dye and on photostability is discussed. pH-selective bulk optodes have been formulated as a first approach to develop ion-selective optodes, and sensitivity, repeatability, lifetime and response time have been determined. The dyes show good analytical behaviour for use as chromoionophores for the development of ion-selective optodes. Reversible (80-87%), fast (tr90%=0.94-2.28 min) and pH-sensitive membranes (slopes of 0.09-0.23 DeltaAbs.pHdec-1, absorbance range 0.19-0.53) have been obtained. Moreover, they exhibit good spectroscopic features for employment with integrated optochemical sensors: absorption maxima of the acidic species in plasticised PVC membranes matched those of 650-670-nm LEDs, high molar absorption coefficients (epsilonacidic=3.5x10(4)-9.3x10(4) L mol-1 cm-1 and epsilonbasic=1.9x10(4)-6.7x10(4) L mol-1 cm-1) and fluorescence.
新型远可见吸收性苯胺基菁染料已被合成，以便未来作为基于整体光极的集成波导吸收式光极中的发色离子载体应用。讨论了杂环、杂环氮取代以及七甲川中心环类型对pKa值（乙醇 - 水溶液中为4.3 - 8.2，增塑PVC膜中为9.5 - 11.0）、染料光谱特性和光稳定性的影响。作为开发离子选择性光极的第一步，已配制了pH选择性整体光极，并测定了其灵敏度、重复性、寿命和响应时间。这些染料作为用于开发离子选择性光极的发色离子载体表现出良好的分析性能。已获得可逆性（80 - 87%）、快速（tr90% = 0.94 - 2.28分钟）且对pH敏感的膜（斜率为0.09 - 0.23 ΔAbs.pHdec-1，吸光度范围为0.19 - 0.53）。此外，它们在与集成光化学传感器一起使用时表现出良好的光谱特性：增塑PVC膜中酸性物种的吸收最大值与650 - 670 nm发光二极管的吸收最大值匹配，具有高摩尔吸收系数（ε酸性 = 3.5×10(4) - 9.3×10(4) L mol-1 cm-1和ε碱性 = 1.9×10(4) - 6.7×10(4) L mol-1 cm-1）以及荧光。
