Tetrabromophenolphthalein Ethyl Ester Research Articles

A Microfluidic Paper-based Analytical Device for Simultaneous Measurement of Albumin, Creatinine and Uric Acid in Urine based on Standard Addition Method

This work describes a simple method for the simultaneous measurement of urinary albumin, creatinine and uric acid using a standard addition approach on a microfluidic paper-based analytical device (µPAD). Hydrophobic barrier of the µPAD was created by stamping indelible ink onto a filter paper. The µPAD was designed with a flower-liked configuration. After aliquoting urine to a central sample zone, the sample flowed to ten surrounding channels, namely “the inner channels”, where the blank (water) or standard solutions had been added. The inner channels were connected to circular reagent zones where reagents had been immobilized. Tetrabromophenolphthalein ethyl ester, alkaline picrate, and a mixed solution of ferric chloride and ferric cyanide were used as the chromogenic reagents for the colorimetric detections of albumin, creatinine, and uric acid, respectively. Each reagent zone was linked with a circular detection zone through a second channel, namely “the outer channels”. The blue-, orange- and greenish-blue colored products were observed in the detection zones for the measurement of albumin, creatinine, and uric acid, correspondingly. A digital image of the µPAD was captured with a mobile phone. The color intensities were evaluated by ImageJTM and were employed for the quantitative analyses. The standard addition calibrations were found to be linear (r2 > 0.99) for the spiked analyte concentrations up to 100 mg L-1 albumin, 1000 mg L-1 creatinine, and 50 mg dL-1 uric acid. The paper platform provided high precision (RSD < 5 %) and good analytical recovery (91.8-109.7 %). Under paired t-test, the results obtained by the developed µPAD and the validating methods were not significantly different at 95 % confidence (albumin: tstat = -0.130, tcri = 3.182, creatinine: tstat = -0.133, tcri = 3.182, and uric acid: tstat = 1.119, tcri = 3.182).

A portable tool for colorimetric detection of corrosion inhibitors using paper-based analytical devices

In this work, we report a complete and portable analytical instrumentation dedicated to the colorimetric analysis of corrosion inhibitors. The construction of the analytical tool was planned based on carousel architecture and it involves a simple combination of a 3D-printed holder containing eight circular zones and an Arduino microcontroller photoelectric sensor. In addition, paper-based analytical devices (PAD) were manufactured in the form of microzones using manual cutting and assembled in the 3D printed holder for performing colorimetric measurements of quaternary amines in wastewater samples from the petroleum industry. A blue dye was used as a model color and the obtained pixels responses through the proposed analytical tool and well-known smartphone-based analysis revealed similar colorimetric intensities, thus clearly demonstrating the high performance of the 3D-printed analytical instrumentation. The target colorimetric reaction occurs via the interaction of ammonium quaternary present in corrosion inhibitors composition with the chromogen 3′, 3″, 5′, 5″ – tetrabromophenolphthalein-ethyl-ester (TBPE) in an acidic medium. Detailed optimization of the colorimetric reaction involving the ammonium quaternary was successfully performed, as well as the evaluation of possible physical–chemical interferences (pH, carbonate levels, and temperature) mostly usual in produced water from petroleum pipelines. Recovery studies of ammonium quaternary in real produced water samples exhibited acceptable performance (88 to 121%). Thus, the obtained results successfully demonstrated that the proposed 3D-printed analytical system associated with PADs offers a huge potential to be used for colorimetric detection of corrosion inhibitors in wastewater samples and it can be used in the point-of-need involving the petroleum industry field.

PH-dependent distribution of the indicator dye tetrabromophenolphthalein ethyl ester between aqueous solution and plasticized polymeric phase: Predicting the lifetime of ion-selective optical sensors

The pH-dependent distribution of the indicator dye tetrabromophenolphthalein ethyl ester (TBPE, chromoionophore VIII) between plasticized polymeric phase and aqueous solution is studied. The commonly utilized algorithms for partition properties calculation are evaluated experimentally in terms of their suitability for the ionized species. The physical-chemical characteristics of TBPE that determine its applicability for use in chemical sensors, namely, the lipophilicity and acidity constant are estimated in the hydrophobic polymeric phase for the first time. The distribution coefficients of the neutral (protonated) and ionized (deprotonated) forms of TBPE are determined in plasticized PVC/water biphase system as 7.2 and 3.8, respectively (logk, ionic strength 1 M, 25 °C). The acidity constant of TBPE in plasticized PVC membrane, pKaPVC−DOS, is estimated spectrophotometrically as 6.1 ± 0.2 log units. The results can be used for developing optical chemical sensors based on TBPE (chromoionophore VIII), in particular for predicting the sensor lifetime, optimization of the sensor operating range and measuring conditions.

Possible use of tetrabromophenolphthalein ethyl ester as a liquid dosimeter

Abstract Aqueous solution of pH indicator dye tetrabromophenolphthalein ethyl ester containing chloral hydrate was studied for its possibility to be used as a liquid dosimeter. The useful measuring range was found to be (0.5–2 kGy) depending on the concentration of both dye and chloral hydrate added. The system has good stability before and after irradiation under different storage conditions. A comparison study between direct irradiation of the dye containing chloral hydrate and indirect method that executed through avoiding exposure of the dye to irradiation and irradiate the chloral hydrate only followed by outputs for interaction with dye was investigated seeking to extend the dose range up to 5 kGy.

Determination of Sulfate Ion with 2-Aminoperimidine Hydrobromide Using an Optode Based on Tetrabromophenolphthalein Ethyl Ester Membrane.

An optode method for the determination of sulfate ion was developed. The optode membrane is 2-nitrophenyl octyl ether-plasticized poly(vinyl chloride) membrane containing tetrabromophenolphthalein ethyl ester. The method is based on formation of an ion associate between the excess of 2-aminoperimidine hydrobromide (Ap) and sulfate ion in the sample solution, and detection of the concentration of the remaining Ap ion by the optode. Under the optimal conditions, a good linear relationship was found to exist between the absorbance of the optode membrane, and concentrations of sulfate ion in a concentration range from 20 to 400 μM. The developed optode method was applied to the determination of sulfate ion in environmental water samples.

Application of a Lithium-ion Selective Metallacrown to Extraction-Spectrophotometric Determination of Lithium in Saline Water.

The solvent-extraction behavior of Li+ and Na+ with a Li+ selective metallacrown, [{Ru(η6-3,5-dimethylanisole)(2,3-pyridinediolate)}3], was investigated in the presence of organic dye anions, 3',3″,5',5″-tetrabromophenolphthalein ethyl ester ([TBPE]-), 2,6-dichloroindophenolate, and picrate ([pic]-). Each alkali metal ion was extracted as a 1:1:1 ternary complex of the metal ion, metallacrown, and anion. The Li+/Na+ extraction selectivity is anion dependent and highest with [pic]-. Therefore, we devised an extraction-spectrophotometric determination method for Li+ in saline water based on the extraction of Li+ using the metallacrown and [pic]- for high selectivity and subsequent replacement of [pic]- in the extracted species with [TBPE]- for high sensitivity. When applying this to artificial seawater samples containing known concentrations of Li+, a linear relationship was observed between the absorbance at 571 nm of the organic phase and the Li+ concentration in the samples. By this method, the determination of Li+ at the sub-ppm level in natural seawater is possible.

A New Microfluidic Polymer Chip with an Embedded Cationic Surfactant Ion-selective Optode as a Detector for the Determination of Cationic Surfactants.

A new microfluidic polymer chip with an embedded cationic surfactant (CS) ion-selective optode (CS-optode) as a detector of flow-injection analysis (FIA) for the determination of CSs was developed. The optode sensing membrane is based on a poly(vinyl chloride) membrane plasticized with 2-nitrophenyl octyl ether containing tetrabromophenolphthalein ethyl ester. Under the optimal flow conditions of the FIA system, the CS-optode showed a good linear relationship between the peak heights in the absorbance, and the concentrations of CS in a concentration range from 50 to 400 μmol dm-3. The sample throughput of the present system for the determination of a CS ion (300 μmol dm-3 zephiramine) was ca. 11 samples h-1. The proposed FIA system was applied to determine the level of CS in dental rinses.

Low-dose film dosimeter based on mixture of AY and TBPE dyed poly(vinyl alcohol)

A new advanced combined Dyed poly(vinyl alcohol) (PVA) film exhibit a new promise dosimeter. It could be established with the aid of casting aqueous solutions of PVA containing mixture of Tetrabromo phenolphthalein ethyl ester dye (TBPE), Acid yellow (AY) and chloral hydrate (CCl3CH(OH)2, (CH) on a horizontal glass plate. It may be considered to be used as recurring low–dose label dosimeters. This bendy thin plastic movie trade its shade undergoes two steps; first from green to yellow, then to red on exposure to γ-ray photons because of the ensuing reducing of pH because of HCl generated from the radiolysis of chloral hydrate. The results indicate that the beneficial dose range from 0.1 to 5 kGy. Effect of various chloral hydrate concentrations on response of the movie became investigated. Dosimetric studies of the film are studied, which shows wonderful stability before and after irradiation (at dark and mild) beside the impact of relative humidity.

A mobile phone-based analyzer for quantitative determination of urinary albumin using self-calibration approach

This work demonstrates use of a smart mobile phone installed with an Android application, termed ‘Albumin smart test’, as an analyzer for quantitative determination of urinary albumin. The reaction between albumin and tetrabromophenolphthalein ethyl ester (TBPE) in the presence of Triton X-100 was employed for detection principle.The mobile phone was exploited with the sample cassette and the test paper. One sample cassette composes of two holders for accommodation of control and test samples. The test paper was designed in order to contain standard colorimetric strip and space for situating the sample cassette. Optical images of the strip and the samples were simultaneously captured in a single shot by a digital camera of the mobile phone and were digitally processed by the developed application for quantification of the albumin concentration based on self-calibration approach. With the advantage of self-calibration, the albumin test by our mobile phone can be performed in ambient light without using any extra module integrated with lighting control device. The other advantages are portability, ease of implementation and rapid analysis (3min) with high precision (RSD≤2.5%) and high accuracy (Recovery=98.7%±1.6). The mobile device was successfully applied to diagnosis of microalbuminuria.

High Dose Film Dosimeter Based on a Mixture of m-cresol Purple and Tetrabromo phenolphthalein Ethyl Ester Dyed Poly (vinyl alcohol)

Gathering two pH indicator dyes m-cresol purple (MCP), tetrabromophenolphthalein ethyl ester (TBPE), previously studied as individual dosimeter each at low dose application in the same polymer matrix (PVA) extends the application dose response to 60 kGy. This flexible plastic film changes its colour from green to red passing through yellow colour on exposure to

Determination of Acid Dissociation Constant of Degradable Tetrabromophenolphthalein Ethyl Ester by Capillary Zone Electrophoresis

An acid dissociation constant of tetrabromophenolphthalein ethyl ester (TBPE) was determined through the measurement of electrophoretic mobility by capillary zone electrophoresis (CZE). Although TBPE is degradable in acidic pH region and it gradually degraded at pH conditions around and below its pKa values in the time scale of the CZE measurement, equilibrium species of interest were detected as a peak-shaped signal with tailing of the degraded species. Changes in electrophoretic mobility of the equilibrium species of TBPE were analyzed at its detectable pH range in the presence of phenol red as a mobility standard. An acid dissociation constant of 3.47 ± 0.06 (pK(a), I = 0.01, 25°C, standard error) was determined for TBPE.

Application of Ion-Association Titration for the Assay of Cyproheptadine Hydrochloride in Pharmaceuticals

Two simple and rapid titrimetric methods are described for the determination of cyproheptadine hydrochloride (CPH) in pharmaceuticals. The proposed methods are based on the solvent extraction-titration of CPH with two ion association reagents, sodium lauryl sulphate (SLS), (method A), and tetraphenylborate (TPB), (method B). In method A, SLS was used as titrant and the titration was carried out in the presence of dilute sulphuric acid and chloroform using dimethyl yellow as indicator, whereas, in method B, the titrant was TPB and the titration was done in Walpole buffer of pH 4.5 and 1, 2-dichloroethane using tetrabromophenolphthalein ethyl ester as indicator. The proposed procedures give sharp end points as the color of the organic phase changes from yellow to pink in method A, and from red-violet to yellow in method B. The methods are applicable over the ranges of 1.0–20.0 and 2.0–9.0 mg of CPH for method A and method B, respectively. The accuracy and precision of the methods are good. The methods were applied successfully to the determination of CPH in tablets, and the results were in agreement with the label claim and those of the reference method.

Micro-Solvent Extraction with Sequential Injection Lab-at-Valve for Successive Determination of Cationic and Nonionic Surfactants

A successive determination of cationic and nonionic surfactants using sequential injection lab-at-valve (SI-LAV) micro solvent extraction has been developed. The method is based on ion association formation between cationic and/or K-nonionic surfactant with tetrabromophenolphthalein ethyl ester (TBPE•H). The blue associate is extracted quickly into 1,2-dichloroethane (DCE) in an extraction coil which is set in a SI-LAV manifold. The segments are dispensed to a pipette tip (like a miniature separation funnel) fitted onto a port of a multi-position valve. This leads to the separation of the aqueous and organic phases. Absorbance of the DCE phase (the bottom part in the pipette tip) can be measured at 610 nm via optic fibers. Without the addition of KCl, absorbance of cationic surfactant can be obtained, while with adding KCl, absorbance of nonionic surfactants can be obtained. The proposed method provides an automated, novel, simple and economical strategy for simultaneous determination of cationic and nonionic surfactants without a membrane separator.

Removal of Nonionic Surfactants from Wastewater Using a Constructed Wetland

Removal of nonionic surfactants from municipal wastewater using a constructed wetland with a horizontal subsurface flow was studied in 2009 and 2010. Extraction spectrophotometry with 3',3″,5',5″-tetrabromophenolphthalein ethyl ester and KCl served to determine the analyte concentrations. Triton(®) X-100 was used as a standard to express the nonionic-surfactant concentrations. Anionic and cationic surfactants were shown not to interfere during the determination. Nonionic surfactants were degraded (to products undeterminable by the method) with a high average efficiency that reached 98.1% in 2009 and 99.1% in 2010, respectively. The average concentration of nonionic surfactants at the inflow was 0.978 mg/l, while it was close to the limit of quantification at the outflow (0.014 mg/l). A significant fraction of nonionic surfactants (38.7%) was already degraded during the pretreatment, and only 14.0% of the nonionic surfactants remained in the interstitial H(2) O taken in the vegetation bed at a distance of 1 m from the inflow zone at a 50-cm depth. Nonionic surfactants were degraded both under aerobic and anaerobic conditions.

Application of ion-association titration for the assay of bupropion hydrochloride in pharmaceuticals

Two simple and rapid titrimetric methods are described for the determination of bupropion hydrochloride (BUPH) in pharmaceuticals. The proposed methods are based on the solvent extraction-titration of BUPH with two ion-association reagents, i.e. sodium lauryl sulphate (SLS) and tetraphenylborate (TPB). In method A, SLS was used as titrant and the titration was carried out in the presence of dilute sulphuric acid and chloroform using dimethyl yellow as indicator whereas in method B, the titrant was TPB and the titration was done in borate-phosphate buffer of pH 6.0 and 1,2-dichloroethane with tetrabromophenolphthalein ethyl ester (TBPE) as indicator. In the two-phase titrations, the proposed procedures give sharp end points as the color of the organic phase changes from yellow to pink in method A and from red-violet to yellow in method B. The methods are applicable over the ranges of 1.0-20.0 and 3.0-10.0 mg of BUPH for method A and method B, respectively. The accuracy and precision of the methods are good. The methods were applied successfully to the determination of BUPH in tablets and the results were in agreement with the label claim and those of the comparison method.

Successive determination of urinary protein and glucose using spectrophotometric sequential injection method

A new sequential injection (SI) system with spectrophotometric detections has been developed for successive determination of protein and glucose. The protein assay is based on ion-association of protein with tetrabromophenolphthalein ethyl ester (TBPE) in the presence of Triton X-100 at pH 3.2. The blue product is monitored for absorbance at 607 nm. For glucose, hydrogen peroxide, generated by the oxidation of glucose in the presence of glucose oxidase immobilized on glass beads packed in a minicolumn, is monitored using iron-catalyzed oxidation reaction of p-anisidine to form a red colored product (520 nm). The SI procedure takes advantage in performing the protein assay during the incubation period for glucose oxidation. Linear ranges were up to 10 mg dL −1 human serum albumin (HSA) with a limit of detection (LOD) (3 σ) of 0.3 mg dL −1, and up to 12.5 mg dL −1 glucose with LOD of 0.08 mg dL −1. R.S.D.s ( n = 11) were 2.7% and 2.5% (for 1 mg dL −1 and 5 mg dL −1 HSA) and 1.4% (9 mg dL −1 glucose). Sample throughput for the whole assay of both protein and glucose is 6 h −1. The automated system has been demonstrated for the successive assay of protein and glucose in urine samples taken from diabetic disease patients, with good agreement with the other methods. This developed SI system is an alternative automation for screening for diabetic diagnosis.

Optical Sensing Membrane Based on Tetrabromophenolphthalein Ethyl Ester for the Determination of Cationic Surfactants

An optical sensing membrane for detection of cationic surfactants was developed. The optical sensing membrane is 2‐nitrophenyl octyl ether‐plasticized poly(vinyl chloride) membrane incorporating tetrabromophenolphthalein ethyl ester (TBPE). The response of the optical membrane to cationic surfactants was a result of extraction of cationic surfactant into the PVC membrane. The protonated TBPE deprotonates forming an ion associate with the extracted cationic surfactant; simultaneously, the deprotonation of the TBPE is accompanied by a spectral change. Namely, the extracted cationic surfactant changes color of the membrane from yellowish green to blue (absorption maximum: 622 nm). The optical membrane responds to cationic surfactants such as Zephiramine and cetyltrimethylammonium bromide in the concentration range from 1 µM to 100 µM.

Test Strips for Lead(II) Based on a Unique Color Change of PVC-film Containing O-Donor Macrocycles and an Anionic Dye

Glassy test strips partially coated with PVC-film including O-donor macrocyclic receptors (L), tetrabromophenolphthalein ethyl ester (TBPE(-)), and a plasticizer sensed Pb(2+) in aqueous solutions by a unique color change. Yellow films successively changed color to green, dark-blue and purple with increases of the Pb(2+) concentration. In contrast with the ordinary "optode", a characteristic absorption band at 525 nm was newly appeared independently of the protonation and deprotonation of HTBPE (yellow to blue). The unique color change occurred only when asymmetric receptors with respect to the basal plane were coupled with Pb(2+). This optical-structural correlation is likely to be induced by the H aggregate of two sets of TBPE(-) in the 1:2 ion-pair, [Pb-L](2+).(TBPE(-))(2). The color change, based on metachromasy, was exclusive for Pb(2+) among common metal cations (Ca(2+), Al(3+), Cd(2+), Zn(2+), Fe(3+), Co(2+), Hg(2+)) and anions (Cl(-), SO(4)(2-), PO(4)(3-), S(2)O(3)(2-)).

Spectrophotometric Flow Injection Analysis of Protein in Urine Using Tetrabromophenolphthalein Ethyl Ester and Triton X-100

A sensitive, rapid and accurate determination of protein in patient urine was carried out by flow injection analysis (FIA) using tetrabromophenolphthalein ethyl ester (TBPE·H) and Triton X-100 at pH 3.0. The detection system was based on the ion association formation between human serum albumin (HSA) and TBPE·H in the micelle formed by Triton X-100. The calibration graph was linear in the range of 0.15 – 12 mg/dL HSA with R 2 = 0.998. The 3σ limit of detection of the proposed FIA method was 0.05 mg/dL at 610 nm. The relative standard deviation (n = 10) of 3.0 mg/dL HSA was 1.2% and the sample throughput was 30 h –1 .

Spectrophotometric Determination of Iron(II) by Using Chitosan Coprecipitation with 1,10-phenanthroline and Tetrabromophenolphthalein Ethyl Ester

A spectrophotometric method utilizing chitosan coprecipitation for the determination of trace iron(II) was examined with 1,10-phenanthroline (phen) and tetrabromophenolphthalein ethyl ester (TBPE). Iron(II) reacted with phen to a stable cheleting complex, [Fe(phen)3]2+. [Fe(phen)3]2+ associated with TBPE− buffered at about pH 6.5 to form the ion associate [Fe(phen)3]2+·(TBPE−)2. A chitosan solution dissolved with acetic acid was added to this solution and chitosan precipitated from the solution immediately. The ion associate [Fe(phen)3]2+·(TBPE−)2 was adsorbed onto the chitosan precipitate. After centrifugation, the supernatant solution was discarded. The chitosan precipitate was dissolved with acetic acid and sodium acetate, and iron(II) could be determined by measuring the absorbance of the solution at 606 nm, that is, the maximum absorption wavelength of TBPE without any pretreatment. The detection limit (S/N = 3) was about 8 ppb. The relative standard deviations (n = 3) for 60 ppb iron(II) was 3.9%. This method is simple for the determination of iron(II) at less than 60 ppb, and there is no use of toxic organic solvents.