Test films for test-determinations on the base of reagents, immobilized in gelatinous gel

Loginova, Lidia P.; Konovalova, O. Yu.

doi:10.1016/j.talanta.2008.07.051

Cited by 12 publications

(3 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…6 Gelatin layers of photographic films were used as a medium for carrying out reactions of different types. 16,[21][22][23][24][25][26] Gelatin is actually a polydisperse mixture of low-molecular polypeptides; 22 the molecules are pronouncedly anisotropic and asymmetric. In fact, the polymer contains a voluminous net of charges and some amount of free ions.…”

Section: Introductionmentioning

confidence: 99%

Protolytic properties of dyes embedded in gelatin films

Никитина¹,

Reshetnyak²,

Svetlova³

et al. 2011

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

O filme de gelatina endurecida fixo em uma base transparente de triacetilcelulose pode ser utilizado como um suporte conveniente para indicadores ácido-base. Azul de bromofenol, verde de bromocresol, eosina, etil-eosina, n-decil-eosina, n-decil-fluoresceína, vermelho neutro e verde de malaquita foram incorporados nos filmes de gelatina por extração em meio aquoso sob condições apropriadas. A absorção de luz dos filmes dopados com corante exibe uma resposta ao pH de soluções tampão aquosas nas quais foram imersos. Valores reprodutíveis das constantes aparentes de dissociação dos indicadores, pK a app , foram calculados pelo tratamento convencional dos valores de pH do tampão aquoso e também para a água absorvida nos filmes de gelatina. Os experimentos com pH abaixo e acima do ponto isoelétrico da gelatina (em torno de pH 5) resultaram em valores de pK a app semelhantes àqueles em meios micelares de tensoativos catiônicos e aniônicos, respectivamente. Os filmes de gelatina modificados por corantes podem ser recomendados para uso em sensores óticos e dispositivos similares.The hardened gelatin film fixed on the transparent triacetylcellulose support can be utilized as a convenient carrier for acid-base indicator dyes. Bromophenol blue, bromocresol green, eosin, ethyleosin, n-decyleosin, n-decylfluorescein, neutral red, and malachite green were embedded into the gelatin films by extracting from aqueous media under appropriate conditions. The light absorption of dye-doped films exhibits a response to the pH values of aqueous buffer solutions, where they were soaked in. The well-reproducible indices of the apparent ionization constants, pK a app , of the indicators were calculated by conventional equating the pH values of the bulk aqueous buffer and those of the 'internal' water into the gelatin films. The experiments with pH below and above the isoelectric point of gelatin (around pH 5) result in pK a app values, which resemble those in micellar media of cationic and anionic surfactants, respectively. The dye-modified gelatin films can be recommended for use in optical sensors and related devices. Keywords: dye-modified gelatin film, indicators, apparent ionization constants, medium effects IntroductionThis paper is devoted to the influence of hardened gelatin media on the spectral and acid-base properties of immobilized xanthene, sulfonephthalein, and some other dyes.The immobilization of reagents in solid matrix (cellulose, ion-exchangers, polymers, silica, xerogels, etc.) 1-7 or using organized solutions, e.g., surfactant-based ones, [8][9][10][11][12] modifies the properties of guest molecules owing to the change of the microenvironment.Such modifications, or medium effects, are most studied and well documented for acid-base indicators. 8,9 In this case, the influence of the microenvironment results in the shift of the indicator equilibrium as compared to that in aqueous media. The main reasons are the local polarity and the local electrical charge. The latter often (but not always) manifests itself in the decre...

show abstract

Section: Introductionmentioning

confidence: 99%

Protolytic properties of dyes embedded in gelatin films

Никитина¹,

Reshetnyak²,

Svetlova³

et al. 2011

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

show abstract

“…There exist inventions of test kits for analysis of compounds with PAAG based on gelatine films modified with vanillin and n-dimethylbenzaldehyde pharmacopoeia reagents [11]. Analysis of these analytical tools application shows acceptable results, but the usage of test kits based on the gelatin films for QC of compounded preparations in pharmacies is not feasible because of the high cost of the test system and the complicated procedure for its manufacturing.…”

Section: Analysis Of Recent Studies and Publications In Which A Solutmentioning

confidence: 99%

Development and standardization of test systems based on filter paper and modified with vanillin reagent

Prokopets

Zdoryk

Georgiyants

2017

ScienceRise: Pharmaceutical Science

View full text Add to dashboard Cite

“…6,7 MTM is, structurally, a pyrazolone derivative with a metassulfonic group. 12 It is, in the organism, hydrolyzed to its pharmacologically active metabolite, the 4-methylamino-antipyrine (MAA), then it is enzymatically metabolized in the liver to 4-formylamino-antipyrine (FAA), a terminal metabolite, and 4-amino-antipyrine (AA). The AA is acetylated to 4-acetyl-amino-antipyrine (AAA) by the enzyme N-acetyltransferase.…”

Section: Introductionmentioning

confidence: 99%

Mechanism of Electro-Oxidation of Metamizole Using Ciclic Voltammetry at a Glassy Carbon Electrode

et al. 2012

View full text Add to dashboard Cite

Cyclic Voltammetry at glassy carbon electrode was applied to study the electro-oxidation of Metamizole, a pro-drug largely used in many countries as analgesic which the therapeutic properties are attributed to its hydrolyzed form. Metamizole presents three oxidation processes in aqueous (Britton Robinson Buffer) and DMF media. The first process was characterized as reversible in the last medium. The differentiation between the process associated with the Metamizole and its respective hydrolyzed form the MAA, was investigated and allowed the proposition of a mechanism for the Metamizole electro-oxidation.

show abstract

Test films for test-determinations on the base of reagents, immobilized in gelatinous gel

Cited by 12 publications

References 22 publications

Protolytic properties of dyes embedded in gelatin films

Protolytic properties of dyes embedded in gelatin films

Development and standardization of test systems based on filter paper and modified with vanillin reagent

Mechanism of Electro-Oxidation of Metamizole Using Ciclic Voltammetry at a Glassy Carbon Electrode

Contact Info

Product

Resources

About