University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Bromothymol blue

  • IUPAC Name: 2-bromo-4-[3-(3-bromo-4-hydroxy-2-methyl-5-propan-2-ylphenyl)-1,1-dioxo-2,1$l^{6}-benzoxathiol-3-yl]-3-methyl-6-propan-2-ylphenol
  • Molecular Formula: C27H28Br2O5S
  • CAS Registry Number: 76-59-5
  • InChI: InChI=1S/C27H28Br2O5S/c1-13(2)17-11-20(15(5)23(28)25(17)30)27(19-9-7-8-10-22(19)35(32,33)34-27)21-12-18(14(3)4)26(31)24(29)16(21)6/h7-14,30-31H,1-6H3
  • InChI Key: NUHCTOLBWMJMLX-UHFFFAOYSA-N

@ ChemSpider@ NIST@ PubChem

Citations 9

"Initial Studies Of Large-bore Flow Injection Systems"
Anal. Chim. Acta 1988 Volume 214, Issue 1-2 Pages 391-396
K. A. McGowan and G. E. Pacey

Abstract: The effects were studied of increasing the i.d. of coiled tubing for flow injection analysis; two systems were investigated as examples, viz, bromothymol blue dye with Na2B4O7 buffer (used to evaluate the physical dispersion coefficient of flow injection manifolds) and the determination of NO3- with sulfanilamide and N-(1-naphthyl)ethylenediamine. Results indicated that the essential characteristics of dispersion were maintained with tubing diameter up to 1.3 mm when the chemical reaction was slow or if stopped-flow conditions were used.
Spectrophotometry Turbidimetry Apparatus Dispersion Large bore tubing Stopped-flow Theory

"Dual-wavelength Photometry With Light Emitting Diodes. Compensation Of Refractive Index And Turbidity Effects In Flow Injection Analysis"
Anal. Chim. Acta 1994 Volume 289, Issue 3 Pages 347-353
Hanghui Liu and Purnendu K. Dasgupta*

Abstract: A mathematical method to compensate for both refractive index and turbidity effects in a dual-wavelength, double beam, dual-flow-cell photometric detection system is described (equations given). The method was demonstrated by determining µM concentrations (8-144 µM) of bromthymol blue in samples containing up to 1.5% whole milk and 60% ethanol with detection at 605 nm. The maximum absolute error was 3.75.
Milk Whole Spectrophotometry Dual detection Refractive index Turbidity

"Generalized Standard Addition In Flow Injection Analysis With UV-visible Photodiode Array Detection"
Anal. Chim. Acta 1995 Volume 304, Issue 2 Pages 229-236
Iben Ellegaard Bechmann*, Lars Nørgaard and Carsten Ridder

Abstract: A FIA system with spectrophotometric diode-array detection was constructed to perform generalized standard addition calibrations. The two line system allowed an undiluted sample stream to be merged with a carrier stream into which the standards were injected. The flow the passed through a knitted coil to the detector cell. The method measured the concentration of the analyte by a single injection and also provided multivariate calibration and outlier detection. The method was demonstrated by determining methyl orange and bromothymol blue in buffered solutions. Samples containing one and two analytes were analyzed as well as samples containing direct interferences. The relative errors were up to 4% for samples containing one analyte and 2-7% for samples containing two analytes. A flow injection analysis system which implements the generalized standard addition method is constructed. The FIA system, which is a model system, is furnished with a photodiode-array spectrophotometer as a detector and is a two-line system one line transports the undiluted sample, which is merged with the second line, into which the standard is injected and dispersed to obtain different amounts of added standard. The performance of the constructed flow system and the partial least-squares solution to the generalized standard addition model is investigated with indicator samples, and an outlier detection technique capable of detecting direct interferences is implemented. By introducing two chasing zones in the standard stream a two analyte calibration space will be spanned, and a generalized standard addition can be performed. Samples containing one analyte and two analytes as well as samples containing direct interferences are analyzed to test the FIA system and the outlier detection method
Spectrophotometry Multivariate calibration Standard additions calibration Interferences Knotted reactor Partial least squares

"High Performance Optical Absorbance Detectors Based On Low Noise Switched Integrators"
Talanta 1993 Volume 40, Issue 9 Pages 1331-1338
Hanghui Liu, Purnendu K. Dasgupta* and Hong J. Zheng,

Abstract: Circuitry based on switched integrator integrated circuit packages was used to construct optical absorbance detectors with improved peak-to-peak noise levels in liquid phase analysis. The electronics are described and the performance data with light emitting diodes as the light source is given. The noise levels varied from 2-3 µAU at 660 nm to 100 µAU at 605 nm. With a rectangular sample cell (50 µm x 1 mm), a 1 mm path length and a slit width of 50 µm the noise level at 660 nm was 10 µAU and the corresponding limit of detection for bromothymol blue was 10 nM.
Spectrophotometry Electronics Light emitting diode

"From Flow Injection To Sequential Injection: Comparison Of Methodologies And Selection Of Liquid Drives"
Analyst 1993 Volume 118, Issue 7 Pages 885-889
Ari Ivaska and Jaromir Ruzicka

Abstract: In sequential injection, sample and reagent zones are stacked in a tubular conduit, merged by flow reversal of the carrier stream and then transported into the detector. The performance of peristaltic pumps and piston pumps was evaluated by monitoring the repeatability of the volume and delivery rates under conditions of forward, stopped and reversed flow. Repeatability studies were performed by aspirating first 250 µL of 0.01 M Na2B4O7 buffer and then different volumes of 0.26 mM bromothymol blue in 0.01 M Na2B4O7 buffer. The flow was then reversed and the bromothymol blue and buffer segments were flushed through the detector. The absorbance was measured at 620 nm. The repeatability of the piston pump was superior to that of the peristaltic pump, but the use of a peristaltic pump is feasible if an RSD of 1-2% is satisfactory and if the sequential injection system can be regularly serviced.
Spectrophotometry Method comparison Sequential injection Theory

"Adsorption Of Tetrahexylammonium - Bromothymol Blue Ion-pairs At The Chloroform-water Interface"
Can. J. Chem. 1991 Volume 69, Issue 1 Pages 88-93
Lawrence Amankwa and Frederick F. Cantwell

Abstract: Porous membrane phase separators are used to study the adsorption of the cation tetrahexylammonium (Q+) of the anion bromothymol blue (HB-) and of the ion-pair formed between them (QHB) at the liq.-liq. interface in a rapidly stirred mixture of CHCl3 and aqueous buffer. Adsorption isotherms in all 3 cases follow the Langmuir equation. The anion HB- is much more strongly adsorbed than the ion-pair QHB. The porous membrane technique readily permits measurement of simultaneous adsorption of the 2 species HB- and QHB, and thereby allows a study of their competitive adsorption. When WHB is adsorbed in the presence of an excess of HB- both the saturated (monolayer) interfacial concentration. of QHB and the logarithm of the adsorption equilibrium. constant for QHB decrease linearly with an increase in interfacial concentration. of HB-. This shows quant. that coadsorption of QHB and HB- involves a direct competition for space at the interface and also that the presence of adsorbed HB- changes the adsorbent properties of the interface. Anal. implications for solvent extraction are discussed.
Sample preparation Ion pair extraction Kinetic Phase separator Solvent extraction Surfactant

"A Microconduit Flow Injection Analysis Demonstration Using A 35-mm Slide Projector"
J. Chem. Educ. 1990 Volume 67, Issue 3 Pages 262-263
Ian D. McKelvie, Terence J. Cardwell and Robert W. Cattrall

Abstract: A 35-mm projection demonstration of flow injection analysis is described that combines the advantages of a highly magnified view of the sample zone as it undergoes dispersion and the ability to show a 3-line flow injection analysis manifold. The microconduit slide described can be used to illustrate any 3-line flow injection analysis in which the analyte yields a strongly colored product. The benefits of stopped-flow injection analysis can be shown using the described arrangement.
Water Spectrophotometry Microfluidic Education

"An Experiment Using Time-based Detection In Flow Injection Analysis"
J. Chem. Educ. 1993 Volume 70, Issue 8 Pages A210-A216
Mary K. Carroll and Julian F. Tyson

Abstract: A lab. experiment suitable for an undergraduate anal. chemical lab. course is described that demonstrates the utility of time-based measurements with doublet peaks in flow injection analysis The system studied here is a simple acid-base titration and the experiment can be adapted to any number of chemical reactions that result in a product that absorbs light of the LED wavelength.
Spectrophotometry Kinetic Peak width Doublet peaks

"Operational Parameters Affecting Zone Penetration In Sequential Injection Analysis"
Process Control Qual. 1992 Volume 3, Issue 1-4 Pages 251-261
G.D. Marshall and J.F. van Staden

Abstract: An introductory outline to sequential injection analysis (SIA) is presented. Design factors affecting the optimum performance of SIA systems are investigated. Four factors are considered: tube diameter, reaction coil geometry, pump speed and selection order. By using solutions of bromothymol blue dye and sodium tetraborate carrier it was shown that: (i) when a tube diameter of 0.8 mm or 1.5 mm was used, improved precision was attained without an excessive decrease in zone penetration; (ii) straight reaction coils allowed greater zone penetration; (iii) faster pump speeds allowed shorter analysis times; (iv) greater dispersion was observed in the first zone selected.
Spectrophotometry Sequential injection Zone penetrating Theory