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References

 

 Solid phase colorimetric determination of iodine in food grade salt using polymethacrylate matrix

 

2019 Food Chemistry
280, с. 15-19

 DOI: 10.1016/j.foodchem.2018.12.037

   A novel colorimetric sensor has been proposed for sensitive and accurate detection of iodine forms using polymethacrylate matrix, which also has the outlook for use with samples without pre-treatment and is suitable to fit in a portable instrument for in situ iodine analysis. This determination method is based on interaction of polymethacrylate matrix with iodine forms followed by measurement of absorbance at 370 nm. The principle of this colorimetric sensor is not ordinary colorimetry, but a new colorimetric strategy that combines solid phase extraction and spectrophotometric determination of a target substance following completion of the color change processes. This method ensures determination of 0.05–80.0 µg·g−1 of iodine with the detection limit of 0.02 µg·g−1. The testing results show that this polymethacrylate matrix can be used for determination of iodine in solutions, food grade salt and iodinated mineral water.   

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 Visual determination of malachite green in sea fish samples

 

2019 Food Chemistry
274, с. 242-245

 

DOI: 10.1016/j.foodchem.2018.08.139

   Polymethylmethacrylate matrix has been developed as an analytical device for visual and spectrophotometric determination of malachite green. Based on the studied effects of different pH levels, temperature, contact time and diverse ions, optimum analysis conditions have been established. For malachite green, the calibration graph was linear in the range of 0.5–30 mg·L−1 in the samples with the detection limit of 1 mg·kg−1. The proposed simple method makes it possible to determine malachite green visually in the concentration range 8–30 mg·L−1 using a colour scale. The method has been implemented for determination of malachite green in various sea fish samples.   

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Transparent polymer sensor for visual and photometrical detection of thiocyanate in oilfield water

 

2019 Journal of Petroleum Science and Engineering
172, с. 960-963

DOI: 10.1016/j.petrol.2018.09.002

  A novel colorimetric sensor has been proposed for sensitive and accurate visual and spectrophotometric detection of thiocyanate using polymethacrylate matrix, which also has the potential for use with samples without pretreatment. The determination method is based on shaping of a Fe3+-thiocyanate colored complex into a transparent polymer matrix, followed by measurement of absorbance at 490 nm. The principle of this colorimetric sensor is not ordinary colorimetry, but a new colorimetric strategy that combines solid phase extraction and spectrophotometric determination of thiocyanate following completion of the color change processes. The method ensures determination of 0.8–30.0 mg L−1 of thiocyanate with the detection limit of 0.3 mg L−1. The proposed simple method makes it possible to determine visually in the concentration above 6.0 mg L−1 using a color scale. The test results show that the polymethacrylate matrix can be used for determination of thiocyanate in oilfield water.  

 

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Kinetic Determination of Thiocyanate by the Reaction of Bromate with Crystal Violet Immobilized in a Polymethacrylate Matrix

 

2018 Journal of Analytical Chemistry
73(9), с. 894-899

DOI: 10.1134/S1061934818090034

  A procedure is proposed for the kinetic solid-phase spectrophotometric determination of thiocyanate using a polymethacrylate matrix. The procedure is based on the Landolt reaction between Crystal Violet immobilized in a polymethacrylate matrix and a bromate oxidizer, accompanied by the discoloration of the indicator in the matrix. During some induction period after the introduction of thiocyanate into the test solution, the dye in the matrix is not discolored. The duration of the induction period is proportional to the concentration of thiocyanate in the solution. The change in the color of the polymethacrylate matrix was recorded by measuring its absorbance at 600 nm. The developed procedure ensures the determination of thiocyanate in the concentration range 0.025–12 mg/L, depending on the Crystal Violet concentration in the matrix. The limit of detection calculated according to the 3s-test is 0.02 mg/L with the indicator concentration in the matrix of 0.06 mg/g. A possibility of using the proposed procedure for the determination of thiocyanate in near-wellbore water is shown.  

 

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Colorimetric sensor for determination of thiocyanate in fossil and drill waters

 

2017 Mendeleev Communications
27(5), с. 529-530

 

DOI: 10.1016/j.mencom.2017.09.034

  A colorimetric sensor is proposed for determination of thiocyanate based on the destruction of mercury–diphenyl–carbazone complex immobilized in the optically transparent polymethacrylate matrix in the concentration range 0.8– 50 mg dm–3 with the detection limit of 0.6 mg dm–3 or visual determination with ‘naked eye’ in the concentration above 1 mg dm–3. The possibility of application of such sensors for determining thiocyanate in fossil and drill waters is shown.  

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Colorimetric sensor for the determination of low-molecular-weight heparin

 

2017 Mendeleev Communications
27(4), с. 419-420

DOI: 10.1016/j.mencom.2017.07.035

 

  A colorimetric sensor was proposed for the visual and solid phase spectrophotometric detection of low-molecular-weight heparin in concentration ranges of 40–120 and 5–40 mg dm–3, respectively, with a detection limit of 2.0 mg dm–3 using a color destruction reaction of toluidine blue immobilized in an optically transparent polymethacrylate matrix  

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Colorimetric scales for chemical analysis on the basis of transparent polymeric sensors

 

 

Journal of Physics: Conference Series 238 (2010) 012051 doi:10.1088/1742-6596/238/1/012051

  Results are presented of implementing a new kind of optical analytical method, in which, as a sensor, membranes are used that are created of reagents immobilized on optically transparent solid polymer matrices. Interacting with a substance under investigation the immobilized reagents change the matrix color. This color change indicates a content of a component determined and persists for a long time. The color difference obtained can be transformed to numerical value that is treated as analytical information. The registration of not reflection and transmission of the light radiation through transparent sensor is promising to reach larger sensitivity up to order of magnitude 102 at low optical absorption.  

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Solid Phase Spectrophotometric Determination of Silver Using Dithizone Immobilized in a Polymethacrylate Matrix

 

Journal of Analytical Chemistry, 2010, Vol. 65, No. 2, pp. 148–152. © Pleiades Publishing, Ltd., 2010.

   Interaction of silver with Dithizone immobilized in a polymethacrylate matrix was studied. A simple procedure was proposed for the solid phase spectrophotometric determination of silver; the detection limit is 0.01 mg/L. The procedure was used for the analysis of mineral waters and the Protargol medication.  

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Solid Phase–Enhanced Photothermal Lensing with Mesoporous Polymethacrylate Matrices for Optical-Sensing Chemical Analysis

 

APPLIED SPECTROSCOPY Volume 67, Number 7, 2013

   Procedures for the photothermal lens determination of metals and organic compounds, on the basis of solid-phase mesoporous optical-sensing materials (polymethacrylate [PMA]) matrices with immobilized reagents, were developed. These procedures combine (i) selective and efficient preconcentration of trace substances to be analyzed in specially designed and synthesized transparent mesoporous PMA plates; (ii) sensitive determination with the reliable and traceable photometric reactions previously developed for classical spectrophotometry; and (iii) the sensitivity enhancement of photothermal lens detection in polymers, which provides at least a ten-fold increase in sensitivity compared with solutions due to polymer thermo-optical properties (solid phase–enhanced thermal lensing). It is shown that the overall sensitivity of photothermal lens measurements in PMA matrices is two orders higher than photometric absorbance measurements for the same excitation source power, which is in good agreement with the expected theoretical sensitivities. Changes in the preparation of transparent PMA plates and analytical procedures for photothermal measurements compared with spectrophotometry are discussed. PMA matrices modified with various analytical reagents were applied to trace determination of mercury(II), Fe(II), Ag(I), Cu(II), and ascorbic acid, with subnanomolar to nanomolar limits of detection.  

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Potentials of Thermal Lens Spectroscopy for Polymethacrylate Optical Sensors

 

Journal of Analytical Chemistry, 2011, Vol. 66, No. 6, pp. 623–628

   The sensitivity of the earlier proposed procedures for the determination of iron(II, III) with 1,10-phenanthroline, silver(I) with dithizone, mercury with copper(II) dithizonate, copper(II) with lead diethyldithiocarbamate, and ascorbic acid with 2,6-dichlorophenolindophenol using polymethacrylate optical sensitive elements for solid phase spectrophotometry is enhanced through the use of thermal lens spectrometry as the most sensitive method of molecular absorption spectroscopy. The limits of detection for all photometric reactions in the polymethacrylate matrix are reduced by an order of magnitude (to 10 nM) with out substantial changes in the experimental conditions.  

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 Redox and Acid–Base Properties of 2,6-Dichlorophenolindophenol
Immobilized on a Polymethacrylate Matrix

 

Journal of Analytical Chemistry, 2010, Vol. 65, No. 1, pp. 17–20.

   The effect of the immobilization of 2,6-dichlorophenolindophenol (DCIP) on a polymethacrylate matrix on its redox and acid–base properties was studied. The ionization constant and formal redox
potentials of the immobilized DCIP were determined by solidphase spectrophotometry. It was shown that the acidity constant and the formal potentials of DCIP decreased upon the immobilization in the polymethacrylate matrix. The results of studying the interaction of ascorbic acid with immobilized DCIP are presented.
 

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Trace Determination of Rhodamine and Eosine in Oil-water Reservoir Using Solid-phase Extraction 

 

Advanced Materials Research, Volume 880, 2014, Pages 276-281

 

   A method for the trace analysis of rhodamine and eosine with colorimetric measurements based on solid-phase extraction (SPE) by transparent polymethacrylate matrix (PMM) is described. Solid-phase extraction on PMM allowed a 380-fold enrichment of the dyes if 10 mL sample volume is used with extraction efficiencies 98%. The method enables the determination of rhodamine to 0.06 mg/L and eosine to 1.2 mg/L combined with a fast and easy sample-preparation (pH-adjusting prior to SPE). Simultaneous extraction and determination of rhodamine and eosine in reservoir samples with high salinity confirmed the applicability and reproducibility of the method. Batch adsorption results indicated that Langmuir isotherm described the adsorption isotherms better.   

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Colorimetric Polymethacrylate Sensor

 

Advanced Materials Research, Volume 880, 2014, Pages 19-24

   The paper describes a new colorimetric sensor. The colorimetric sensors were made of optically transparent polymethacrylate matrix with physically immobilized analytical reagent which is responsible for the extraction of the analyte into the sensing material and changing its color. The developed colorimetric sensor can be used in determination of various analytes using both solid-phase spectrophotometer and naked eye.   

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Polymethacrylate optodes: A potential for chemical digital color analysis

 

Measurement: Journal of the International Measurement Confederation
Volume 51, Issue 1, May 2014, Pages 464-469

  The paper describes results of implementing a new kind of optical analytical method, digital color analysis (DCA), in which colorimetric polymethacrylate sensors (optodes) are used. The optodes are made of optically transparent polymethacrylate matrix with physically immobilized analytical reagent which is responsible for the extraction of the analyte into the sensing material and changing its color. The developed optodes can be used in determination of various analytes using both solid-phase spectrophotometer and naked eye. In order to improve accuracy and sensitivity of the naked-eye determination, it is possible to measure visible color changes using digital imaging of the polymethacrylate optode. The digital images then can be represented as basic color (e.g. RGB) data. The DCA determinations of Cu (II), Ag (I) and Co (II) have indicated that the developed optodes are linear in concentration ranges 0.02-0.30; 0.02-0.20 and 0.05-0.25 mg L-1 appropriately with corresponding practical detection limits of 0.01; 0.02 and 0.07 mg L-1  

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Polymethacrylate Colorimetric Sensor for Evaluation of Total Antioxidant Capacity


Procedia Chemistry, Volume 10, 2014, Pages 97-102

  A new colorimetric sensor using an immobilized chromogenic redox reagent was devised for measuring the total antioxidant level in a liquid sample without requiring sample pretreatment. The reagent, Fe(III) – 1,10-phenanthroline (Fe(III)-phen), was immobilized into a polymethacrylate matrix (PMM), and the absorbance changes associated with the formation of the highly colored Fe(II)-phen chelate as a result of reaction with antioxidants was measured at 510 nm. The developed optical sensor was used to screen total antioxidant capacity of some black and green teas, red and white wines.  

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Solid Phase Sorption of Phenols on Metals Acetylacetonates


Procedia Chemistry, Volume 10, 2014, Pages 103-107

  The solid phase extraction properties of surface layers of Eu(III), Al(III), Fe(III), Cr(III) acetylacetonates are compared for sorption some phenols and chlorophenols. The effects of the energies of adsorption and complexation on the retention of various sorbates were calculated. GC methods with preconcentration are proposed to evaluate phenols by means of solid-phase extraction on a sorbent with a surface layer of Eu acetylacetonate with extraction effectiveness of 85%.  

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 Solid-phase extraction of fluorinated benzoic acids for the chromatographic analysis of oil tracer agents

 Mendeleev Communications

Volume 25, Issue 2, March–April 2015, Pages 159–160

   The extraction of fluorinated benzoic acids from aqueous solutions and water–oil emulsions with preconcentration on a sorbent with a surface layer of Zn, Cu, Co and Ni phthalocyanines is proposed.  

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Solid-phase spectrophotometric iodometric determination of nitrite and selenium(IV) using a polymethacrylate matrix

 

 

2017 Journal of Analytical Chemistry
72(5), с. 546-550

 

DOI: 10.1134/S1061934817030054

 

 

   Procedures for the iodometric solid-phase spectrophotometric determination of nitrite and selenium(IV) using a polymethacrylate matrix are proposed. The procedures are based on the reaction of nitrite and selenium(IV) with iodine in an acidic medium with the release of free iodine in amounts equivalent to those of the substances to be determined, extraction of the iodine formed with a polymethacrylate matrix, and measurement of absorbance of the matrix at 370 nm. The developed procedures ensure the determination of 0.01–0.12 mg/L of nitrite and 0.05–0.40 mg/L of selenium(IV) with limits of detection of 0.005 and 0.03 mg/L, respectively. It was shown that the proposed procedures can be applied to the determination of selenium(IV) in mineral water and nitrites in vegetables and soil.  

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Determination Of Antioxidant Composition In Berry Juices Using Solid Phase Extraction With Copper Phthalocyanine

Key Engineering Materials Vol. 670 (2016) pp 213-217 © (2016) Trans Tech Publications, 
doi:10.4028/www.scientific.net/KEM.670.213

 

   

The paper studies selective extraction of organic fractions with antioxidant activity from plant raw materials on the new sorbent with surface layer of phthalocyanine metal complexes and further HPLC determination. The possibility of sorption concentration of the antioxidant substances amount, which include mostly vitamin B groups, on the layer of copper phthalocyanine on polymer sorbent Polysorb-2. We determined antioxidant composition of honeysuckle, huckleberry and cowberry juice, namely, gallus, gentisinic, chlorogenic, caffeic, cumaric and p-methoxybenzoic acids; epicatechin and quercetine. Detection limit of this technique is 5 mg/l using copper phthalocyanine in the concentrator.

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Sensor Based on Metals Acetylacetonates for Determination of Organic Substances Vapour in the Atmosphere

Key Engineering Materials Vol. 670 (2016) pp 241-245 
© (2016) Trans Tech Publications, 
doi:10.4028/www.scientific.net/KEM.670.241

   

There has been designed a sensor with detectors based on adsorption layers of metals acetylacetonates to measure air pollution components concentration. The electrical conductivity of
the obtained sensor was studied under various synthesis conditions, temperature and detected substances kinds. The sensor was tested on model gaseous mixture and applied to detect organic substances in the environment.

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 A Colorimetric Sensor Based on a Polymethacrylate Matrix with Immobilized 1-(2-Pyridylazo)-2-Naphthol for the Determination of Cobalt

Journal of Analytical Chemistry, 2015, Vol. 70, No. 12, pp. 1475–1479. © Pleiades Publishing, Ltd., 2015 

DOI: 10.1134/S1061934815120060

 

   

A colorimetric sensor is proposed for the determination of cobalt. It is prepared by immobilizing 1-(2-pyridylazo)-2-naphthol (PAN) in an optically transparent polymethacrylate matrix. The conditions for determining cobalt by the proposed colorimetric sensor are found in the study of the complexation of cobalt with a PAN modified polymethacrylate matrix. The determination is based on the interaction of the sensor with a cobalt solution at pH 4 for 5 min, followed by the measurement of absorbance at 620 nm. The sensor ensures the determination of 0.05–0.50 mg/L of cobalt with the detection limit 0.03 mg/L. It is demonstrated that the sensor can be used for the determination of cobalt in the Cyanocobalamin medical preparation and potable water.

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Effect of Polyethylene Glycol Immobilized into a Polymethacrylate Matrix on the Sorption of Rhodamine

1876-6196 © 2015 The Authors. Published by Elsevier B.V. 

Procedia Chemistry 15 ( 2015 ) 21 – 26
doi: 10.1016/j.proche.2015.10.004

 

 

   

Combined matrix PMMA and PEG, having a polymethacrylate backbone and hydrophilic PEG chains, has been synthesized and
applied for the design of transparent colour sensors. Introduction of the hydrophilic PEG chains in the PMMA bulk overcomes the limitations caused by the hydrophobicity of PMMA, and exhibits good wettability, stable and specific adsorption. We suppose that the adsorption of rhodamine on such networks depends on the chemical composition of the system and describes the interaction of the xanthene dye with the polymers.

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