Analytical performance of an optical pH sensor for acid-base titration

Moreno, María Cruz Iglesias; Jiménez, Mercedes; Conde, Concepción Pérez; Cámara, Carmen

doi:10.1016/s0003-2670(00)82758-0

Cited by 34 publications

(10 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…HPTS is a widely used pH indicator for fluorescence pH sensors because of its physiological pH range, high quantum yield, large Stokes' shift, and the presence of three negatively charged sulfonate groups available for electrostatic immobilization. 36, [46][47][48] For the purposes of routine analytical use, it might be noted that compared with the measured variation of the acid form of immobilized HPTS at 408 nm, the variation in base form at 460 nm resulted in a larger linear variation region from pH 5.0 to 7.3 (correlation coefficient 0.99). Figure 6 shows the pH behavior of a HPTS-loaded film examined in absorption mode.…”

Section: Resultsmentioning

confidence: 99%

Optically Transparent Polyelectrolyte−Silica Composite Materials: Preparation, Characterization, and Application in Optical Chemical Sensing

Shi

Seliskar

1997

Chem. Mater.

View full text Add to dashboard Cite

A series of polyelectrolyte-containing silica composite materials have been prepared by sol-gel processing. These optically transparent composites have been characterized by scanning electron microscopy and UV-visible spectrophotometry. These materials can be processed into monolithic disks and thin films. The thicknesses of spin-coated films of these materials on glass can be varied from 0.13 to 3.5 µm as determined by an optical interference method. These materials are ion exchangeable and less brittle than the parent silica glass due to the incorporation of the organic polyelectrolyte. These new composites retain the nanoscale porosity and optical transparency into the ultraviolet of the parent silica sol-gel glasses, making them attractive host matrixes for the immobilization of ionizable dye molecules and chemical reagents. An optical pH sensing platform (0.9 × 2.5 cm) based on the electrostatic immobilization of HPTS (8-hydroxy-1,3,6-pyrenetrisulfonic acid trisodium salt) in a PDMDAAC (poly(diallyldimethylammonium chloride))-silica composite film was fabricated and evaluated. The results clearly demonstrate that this platform is easy to construct with high batch reproducibility and can be regenerated by simple solution ion exchange. The platform is usable in both the modes of absorption and fluorescence, making it versatile. Having a fast response time (ca. ∼2 s to more than 2 units of pH change), the platform is also highly resistant to dye leaching and storage degradation over a period of months.

show abstract

Section: Resultsmentioning

confidence: 99%

Optically Transparent Polyelectrolyte−Silica Composite Materials: Preparation, Characterization, and Application in Optical Chemical Sensing

Shi

Seliskar

1997

Chem. Mater.

View full text Add to dashboard Cite

show abstract

“…Because of the negative charge, the sulfonate groups enable strong electrostatic immobilization on ion exchange resins. 265 , 273 , 299 , 300 , 317 , 318 This, however, increases the cross-talk to ionic strength due to high charge of the matrix and may introduce hysteresis and impaired diffusion due to Donnan potential. Leaching of positively or negatively charged indicators can be reduced by replacing the usually inorganic counterion (such as sodium ion or chloride) by an organic counterion.…”

Section: Overview Of Commonly Used Absorptiometric Ph Probesmentioning

confidence: 99%

Optical Sensing and Imaging of pH Values: Spectroscopies, Materials, and Applications

2020

View full text Add to dashboard Cite

This is the first comprehensive review on methods and materials for use in optical sensing of pH values and on applications of such sensors. The Review starts with an introduction that contains subsections on the definition of the pH value, a brief look back on optical methods for sensing of pH, on the effects of ionic strength on pH values and p K a values, on the selectivity, sensitivity, precision, dynamic ranges, and temperature dependence of such sensors. Commonly used optical sensing schemes are covered in a next main chapter, with subsections on methods based on absorptiometry, reflectometry, luminescence, refractive index, surface plasmon resonance, photonic crystals, turbidity, mechanical displacement, interferometry, and solvatochromism. This is followed by sections on absorptiometric and luminescent molecular probes for use pH in sensors. Further large sections cover polymeric hosts and supports, and methods for immobilization of indicator dyes. Further and more specific sections summarize the state of the art in materials with dual functionality (indicator and host), nanomaterials, sensors based on upconversion and 2-photon absorption, multiparameter sensors, imaging, and sensors for extreme pH values. A chapter on the many sensing formats has subsections on planar, fiber optic, evanescent wave, refractive index, surface plasmon resonance and holography based sensor designs, and on distributed sensing. Another section summarizes selected applications in areas, such as medicine, biology, oceanography, bioprocess monitoring, corrosion studies, on the use of pH sensors as transducers in biosensors and chemical sensors, and their integration into flow-injection analyzers, microfluidic devices, and lab-on-a-chip systems. An extra section is devoted to current challenges, with subsections on challenges of general nature and those of specific nature. A concluding section gives an outlook on potential future trends and perspectives.

show abstract

“…Also by using optodes, real time analysis can be performed. Sensing material of an optical sensor can be adsorbed on the surface of support materials chemically and physically 26 ; chemically immobilized in an appropriate support [27][28] or physically entrapped in polymeric matrices [29][30][31] .…”

Section: Introductionmentioning

confidence: 99%

Design and fabrication of a novel optical sensor for determination of trace amounts of lutetium ion

Zare‐Dorabei¹,

Ganjali²,

Rahimi³

et al. 2013

10.5267/j.ccl

View full text Add to dashboard Cite

In this study, for the first time we report a highly selective and sensitive lutetium ions chemical optical sensor based on immobilization of a asymmetrically S-N Schiff's base, namely N-(thien-2-ylmethylene)pyridine-2,6-diamine (TPD) on a triacetylcellulose membrane. This optode exhibits a linear range of 5.0 ×10 -7 -1.0 ×10 -5 M of the Lu(III) ion concentration with a detection limit of 9.3 ×10 -8 M at a wavelength of 336 nm. The influence of responsible factors for improving sensitivity of the sensor was studied and identified. Response time of the newly designed optode was within 20-30 s depending on the Lu(III) ion concentration. Response of the optical sensor is independent of the pH of the solution in the range of 3.0-9.0. It manifests advantages of fast response time, low detection limit and most significantly, very good selectivity with respect to a number of lanthanide ions. The sensor can readily be regenerated with thiourea solutions and its response was reversible and reproducible. This optode was applied to the determination of Lu(III) in aqueous and CRM samples.

show abstract

Analytical performance of an optical pH sensor for acid-base titration

Cited by 34 publications

References 13 publications

Optically Transparent Polyelectrolyte−Silica Composite Materials: Preparation, Characterization, and Application in Optical Chemical Sensing

Optically Transparent Polyelectrolyte−Silica Composite Materials: Preparation, Characterization, and Application in Optical Chemical Sensing

Optical Sensing and Imaging of pH Values: Spectroscopies, Materials, and Applications

Design and fabrication of a novel optical sensor for determination of trace amounts of lutetium ion

Contact Info

Product

Resources

About