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1.
Molecules ; 29(10)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38792113

RESUMO

The features for assessing the authenticity of wines by region of origin are studied, based on the relationship between the mineral composition of the wine, the grapes, and the soil profile (0 to 160 cm) from the place of growth of Cabernet Sauvignon grapes. Soil, grape, and wine samples were taken from the territories of six vineyards in the Anapa district of Krasnodar Territory, Russia. Using the methods of ICP-OES, thermal, and X-ray phase analysis, the soils were differentiated into three groups, differing in mineralogical and mineral compositions. The soil samples of the first group contained up to 31% quartz, the second group up to 25% quartz and 19% mixed calcite, and the third group up to 32% calcite and 15% quartz. The formation of the elemental image of the grapes was studied, taking into account the total content and mobile forms of metals in the soil. The territorial proximity of the vineyards did not affect the extraction of elements from the soil into the grape berry, and the migration of metals for each territory was selective. According to the values of the biological absorption coefficient, the degree of transition of metals from the soil to a berry was estimated. For K, Ti, Zn, Rb, Cu, and Fe in all berries, the coefficient was higher than 1.00, which means that the berry extracts contained not only mobile-form, but also difficult-to-dissolve metal compounds. The migration of macro-components from the soil to the berry was low, and amounted to 6-7% for Ca, 0.8-3.0% for Na, and 25-70% for Mg of the concentration of their mobile forms. For all territories, the maximum correlation between metal concentrations in grapes and soil was observed for samples from a depth of 0-40 cm. The discriminant model based on concentrations of Rb, Al, K, Sr, Co, Na, Pb, Ca, and Ni showed the formation of clusters in the territories of vineyard cultivation. The developed model allow the problems of identifying wines by region to be solved with high accuracy, using their elemental image.

2.
Sensors (Basel) ; 23(2)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36679417

RESUMO

A new version of a sensor for temperature measurements in the case of strong laser intensity fluctuation was developed. It was based on tunable diode laser absorption spectroscopy (TDLAS) with wavelength modulation, logarithmic conversion of the absorption signal, and detection of the first harmonic of the modulation frequency. The efficiency of the technique was demonstrated under experimental conditions with excess multiplicative noise. Temperature was evaluated from the ratio of integrated absorbance of two lines of the water molecule with different lower energy levels. Two algorithms of data processing were tested, simultaneous fitting of two spectral ranges with selected absorption lines and independent fitting of two absorption lines profiles. The correctness of the gas temperature evaluation was verified by simultaneous measurements with a commercial thermocouple. An error in temperature evaluation of less than 40 at 1000 K was achieved even when processing a single scan of the diode lasers.


Assuntos
Algoritmos , Lasers Semicondutores , Temperatura , Análise Espectral , Água
3.
Molecules ; 28(16)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37630219

RESUMO

This paper considers the features of determining the total tin content in waters with different salinity. Direct ICP-spectrometric analysis of sea waters with a salinity of more than 6‱ significantly reduced the analytical signal of tin by 70% (ICP-MS) and 30% (ICP-OES). The matrix effect of macrocomponents was eliminated by generating hydrides using 0.50 M sodium borohydride and 0.10 M hydrochloric acid. The effect of transition metals on the formation of tin hydrides was eliminated by applying L-cysteine at a concentration of 0.75 g/L. The total analyte concentrations, considering the content of organotin compounds, were determined after microwave digestion of sample with oxidizing mixtures based on nitric acid. The generation of hydrides with the ICP-spectrometric determination of tin leveled the influence of the sea water matrix and reduced its detection limit from 0.50 up to 0.05 µg/L for all digestion schemes. The developed analysis scheme made it possible to determine the total content of inorganic and organic forms of tin in sea waters. The total content of tin was determined in the waters of the Azov and Black seas at the levels of 0.17 and 0.24 µg/L, respectively.

4.
Molecules ; 28(18)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37764390

RESUMO

In this study, determination of the inorganic and organic forms of tin in waters of different salinities is considered. The possibility of the separation of speciations of tin using liquid-liquid extraction (LLE); precipitation with fluorides, iodides, ammonia, and iron (III) chloride; and sorption of organotin compounds (OTCs) was studied. The LLE and analyte precipitation methods proved to be ineffective. Inorganic and organic forms of tin were separated by the sorption of OTCs using silica gel sorbent Diapak C18. Under optimized conditions, a technique for the separate determination of the forms of tin in natural waters was developed. The technique combines hydride generation and microwave mineralization of solutions followed by ICP spectrometry. The inorganic forms of tin were determined after their solid-phase separation from organotin compounds. The lower limits of analyte quantification were 0.03 µg/L (ICP-MS) and 0.05 µg/L (ICP-OES), which provide separate determinations of inorganic and organic forms of tin in waters with different salinities. The content of OTCs in water was determined by subtracting the inorganic concentration from the total concentration of tin. The technique will allow a comprehensive assessment of the toxicological impact of tin speciations on the aquatic ecosystem.

5.
Molecules ; 28(11)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37298795

RESUMO

The possibility of establishing the varietal and territorial affiliation of wines by the content of rare earth elements (REE) in them was studied. ICP-OES and ICP-MS with subsequent chemometric processing of the results were applied to determine the elemental image of soils containing negligible REE amounts, grapes grown on these soils, and wine materials of Cabernet Sauvignon, Merlot, and Moldova varieties produced from these grapes. To stabilize and clarify wine materials, the traditional processing of wine materials with various types of bentonite clays (BT) was used, which turned out to be a source of REE in the wine material. Discriminant analysis revealed that the processed wine materials were homogeneous within one denomination and that those of different denominations were heterogeneous with respect to the content of REE. It was found that REE in wine materials were transferred from BT during the processing, and thus they can poorly characterize the geographical origin and varietal affiliation of wines. Analysis of these wine materials according to the intrinsic concentrations of macro- and microelements showed that they formed clusters according to their varietal affiliation. In terms of their influence on the varietal image of wine materials, REE are significantly inferior to macro- and microelements, but they enhance their influence to a certain extent when used together.


Assuntos
Metais Terras Raras , Vitis , Vinho , Vinho/análise , Análise Discriminante , Metais Terras Raras/análise , Geografia
6.
Molecules ; 27(22)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36431854

RESUMO

We discuss the features involved in determining the titanium dioxide nanoparticle (TiO2NP) sizes in cosmetic samples via single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) in the millisecond-time resolution mode, and methods for considering the background signal. In the SP-ICP-MS determination of TiO2NPs in cosmetics, the background signal was recorded in each dwell time interval due to the signal of the Ti dissolved form in deionized water, and the background signal of the cosmetic matrix was compensated by dilution. A correction procedure for the frequency and intensity of the background signal is proposed, which differs from the known procedures due to its correction by the standard deviation above the background signal. Background signals were removed from the sample signal distribution using the deionized water signal distribution. Data processing was carried out using Microsoft Office Excel and SPCal software. The distributions of NP signals in cosmetic product samples were studied in the dwell time range of 4-20 ms. The limit of detection of the NP size (LODsize) with the proposed background signal correction procedure was 71 nm. For the studied samples, the LODsize did not depend on the threshold of the background signal and was determined by the sensitivity of the mass spectrometer.


Assuntos
Cosméticos , Nanopartículas , Titânio/química , Nanopartículas/química , Cosméticos/análise , Água
7.
Molecules ; 27(19)2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36235280

RESUMO

In this paper, we propose the combined procedure of noble metal (NM) determination, including fire assay, acid digestion, and reversible dynamic sorptive preconcentration, followed by flow-injection ICP-MS. Reversible preconcentration of all NMs was carried out using micro-column packed new PVBC-VP sorbent and elution with a mixture of thiourea, potassium thiocyanate, and HCl, which recovers Pd, Ir, Pt, and Au by 95% and Ru, and Rh by 90%. The proposed procedure was approved using certified reference materials.


Assuntos
Metais , Tioureia , Análise Espectral
8.
Int J Mol Sci ; 22(22)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34830136

RESUMO

The selection of technological parameters for nanoparticle formulation represents a complicated development phase. Therefore, the statistical analysis based on Box-Behnken methodology is widely used to optimize technological processes, including poly(lactic-co-glycolic acid) nanoparticle formulation. In this study, we applied a two-level three-factor design to optimize the preparation of nanoparticles loaded with cobalt (CoTPP), manganese (MnClTPP), and nickel (NiTPP) metalloporphyrins (MeP). The resulting nanoparticles were examined by dynamic light scattering, X-ray diffraction, Fourier transform infrared spectroscopy, MTT test, and hemolytic activity assay. The optimized model of nanoparticle formulation was validated, and the obtained nanoparticles possessed a spherical shape and physicochemical characteristics enabling them to deliver MeP in cancer cells. In vitro hemolysis assay revealed high safety of the formulated MeP-loaded nanoparticles. The MeP release demonstrated a biphasic profile and release mechanism via Fick diffusion, according to release exponent values. Formulated MeP-loaded nanoparticles revealed significant antitumor activity and ability to generate reactive oxygen species. MnClTPP- and CoTPP-nanoparticles specifically accumulated in tissues, preventing wide tissue distribution caused by long-term circulation of the hydrophobic drug. Our results suggest that MnClTPP- and CoTPP-nanoparticles represent the greatest potential for utilization in in anticancer therapy due to their effectiveness and safety.


Assuntos
Complexos de Coordenação/farmacocinética , Metaloporfirinas/farmacocinética , Metais/química , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Porfirinas/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Liberação Controlada de Fármacos , Feminino , Células HeLa , Hemólise/efeitos dos fármacos , Humanos , Células MCF-7 , Metaloporfirinas/química , Metaloporfirinas/farmacologia , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Distribuição Tecidual , Difração de Raios X
9.
Sensors (Basel) ; 20(21)2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33158251

RESUMO

A new scheme for a calibration-free diode laser absorption spectroscopy (DLAS) sensor for measuring the parameters of harsh zones is proposed. The key element of the scheme is a micro-prism retroreflector (MPRR). The MPRR facilitates an increase in the mechanical stability of the sensor and a decrease in the background thermal radiation in the hot areas of a tested zone. Reduction in the broadband thermal emission allowed the application of a differential logarithmic conversion (LC) technique for elimination of the residual amplitude modulation and other sources of non-selective attenuation of the probing laser beam. LC allows the use of a 1f-wavelength modulation spectroscopy (WMS) detection scheme. Combination of LC and a 1f-WMS algorithm provided a new modification of calibration-free DLAS, which could be particularly useful for probing harsh zones with pronounced strong turbulence and high levels of acoustic and electrical noise. The influence of the experimental parameters and characteristics of the main electronic components of the recording and processing system on the accuracy of the integral line intensity determination is investigated theoretically and experimentally. The proposed optical scheme of a DLAS sensor and algorithm for the data processing allowed the integral intensity of an absorption line to be obtained. The potential for the scheme was exemplified with a single water vapor absorption line at 7185.6 cm-1. Simultaneous detection of several absorption lines and data processing using the developed algorithm provides the final goal of a DLAS sensor-determination of temperature and partial pressure of a test molecule in a probed gas volume. The developed scheme allows the spatial multiplexing of the radiation of different diode lasers (DLs), which can be used if various test molecules are to be detected, or absorption lines of a test molecule are detected over different wavelength intervals.

10.
Sensors (Basel) ; 18(5)2018 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-29772830

RESUMO

A new algorithm for the estimation of the maximum temperature in a non-uniform hot zone by a sensor based on absorption spectrometry with a diode laser is developed. The algorithm is based on the fitting of the absorption spectrum with a test molecule in a non-uniform zone by linear combination of two single temperature spectra simulated using spectroscopic databases. The proposed algorithm allows one to better estimate the maximum temperature of a non-uniform zone and can be useful if only the maximum temperature rather than a precise temperature profile is of primary interest. The efficiency and specificity of the algorithm are demonstrated in numerical experiments and experimentally proven using an optical cell with two sections. Temperatures and water vapor concentrations could be independently regulated in both sections. The best fitting was found using a correlation technique. A distributed feedback (DFB) diode laser in the spectral range around 1.343 µm was used in the experiments. Because of the significant differences between the temperature dependences of the experimental and theoretical absorption spectra in the temperature range 300⁻1200 K, a database was constructed using experimentally detected single temperature spectra. Using the developed algorithm the maximum temperature in the two-section cell was estimated with accuracy better than 30 K.

11.
Mol Pharm ; 13(11): 3712-3723, 2016 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-27654150

RESUMO

Targeted delivery of anticancer drugs to brain tumors, especially glioblastoma multiforme, which is the most frequent and aggressive type, is one of the important objectives in nanomedicine. Vascular endothelial growth factor (VEGF) and its receptor type II (VEGFR2) are promising targets because they are overexpressed by not only core tumor cells but also by migrated glioma cells, which are responsible for resistance and rapid progression of brain tumors. The purpose of the present study was to develop the liposomal drug delivery system combining enhanced loading capacity of cisplatin and high binding affinity to glioma cells. This was achieved by using of highly soluble cisplatin analogue, cis-diamminedinitratoplatinum(II), and antibodies against the native form of VEGF or VEGFR2 conjugated to liposome surface. The developed drug delivery system revealed sustained drug release profile, high affinity to antigens, and increased uptake by glioma C6 and U-87 MG cells. Pharmacokinetic study on glioma C6-bearing rats revealed prolonged blood circulation time of the liposomal formulation. The above features enabled the present drug delivery system to overcome both poor pharmacokinetics typical for platinum formulations and low loading capacity typical for conventional liposomal cisplatin formulations.


Assuntos
Cisplatino/metabolismo , Glioma/metabolismo , Lipossomos/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Linhagem Celular Tumoral , Cisplatino/química , Citometria de Fluxo , Células HEK293 , Humanos , Lipossomos/química , Microscopia Confocal , Ratos , Fator A de Crescimento do Endotélio Vascular/imunologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/imunologia
12.
Heliyon ; 10(8): e29607, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38681543

RESUMO

An important aspect of assessing the authenticity of wines is its geographical origin. The aim of the work is to authenticate by geographical origin according to the data of the ICP-spectrometric and chemometric analysis of elemental "images" of wines produced from white grape varieties Chardonnay, Riesling and Muscat grown in four regions of the Krasnodar Territory, Russia. The difference in the contents of Al, Ba, Ca and Rb in wines was found depending on the variety, and Al, Ba, Rb, Fe, Li, Sr - depending on the region of grape growth. Different models of the experimental data processing were used for attribution of the produced varieties of wine to the area of the grape's growth. The criterion for the quality of the constructed models was the accuracy of the attribution of a wine variety to the area of the grape's growth (%). Analysis of the elemental analysis data of 153 wine samples showed that in terms of attribution accuracy, automated neural networks (100 %) are preferred among machine learning methods, followed by support vector machines (98.69 %) and general discriminant analysis (94.77 %). The applied mathematical models enabled the revealing of the cluster structure of the analyzed wine varieties and their attribution to the area of a grape growth with high accuracy. Sr, Li and Fe concentrations in wines were found as the dominating predictors in the constructed models for definition of the geographical origin of wines. The combination of ICP-spectrometric analysis data with the capabilities of statistical modeling of machine learning methods focused on large-dimensional data made it possible to successfully solve small-dimensional problems of the definition of the geographical origin of wines by their elemental composition and variety.

13.
Appl Spectrosc ; : 37028241263567, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38881037

RESUMO

The almost-two-centuries history of spectrochemical analysis has generated a body of literature so vast that it has become nearly intractable for experts, much less for those wishing to enter the field. Authoritative, focused reviews help to address this problem but become so granular that the overall directions of the field are lost. This broader perspective can be provided partially by general overviews but then the thinking, experimental details, theoretical underpinnings and instrumental innovations of the original work must be sacrificed. In the present compilation, this dilemma is overcome by assembling the most impactful publications in the area of analytical atomic spectrometry. Each entry was proposed by at least one current expert in the field and supported by a narrative that justifies its inclusion. The entries were then assembled into a coherent sequence and returned to contributors for a round-robin review.

14.
Data Brief ; 42: 108163, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35496491

RESUMO

The research data on the effect of bentonite clays (BT) in the process of clarification and stabilization on the elemental composition determining the varietal affiliation of wines are analyzed in the article. The initial objects were three untreated wine samples produced from Cabernet Sauvignon, Merlot and Moldova grape varieties in the Krasnodar Territory. Clarification and stabilization of untreated wine samples was carried out with 32 samples of BT of various degrees of dispersion and trademarks. The concentrations of metals, i.e., macro- and microelements, in bentonite clays, untreated and treated wine samples were determined by ICP-OES and ICP-MS methods. The results of the influence of stabilization and clarification of various wines with 32 BT on their elemental composition based on the concentrations of 16 micro- and macroelements isolated chemometrically from 39 elements are shown in the article. The elemental composition of the initial wine varieties as well as wine samples obtained after their clarification and stabilization (32 samples per each variety) was established based on the results of three parallel measurements. The aim of the study was to assess the contribution of macro- and microelements to the formation of the elemental image of wines determining their varietal affiliation. Using discriminant analysis and principal component analysis, the presence of cluster structures in treated and untreated wine samples was established in accordance with their varieties with respect to the concentrations of isolated macro- and microelements. The role of microelements was shown to be higher than that of macroelements in the formation of varietal image of wines. The combination of the most informative macro- and microelements in determining the cluster structure of wine samples increases the possibilities of assessing the intravarietal similarity and intervarietal differences of wines.

15.
Anal Bioanal Chem ; 400(3): 709-14, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21359996

RESUMO

Urine analysis gives an insight into the excretion of the administered drug which is related to its reactivity and toxicity. In this work, the capability of inductively coupled plasma mass spectrometry (ICP-MS) to measure ultratrace metal levels was utilized for rapid assaying of gallium originating from the novel gallium anticancer drug, tris(8-quinolinolato)gallium(III) (GaQ(3)), in human urine. Sample dilution with 1% (v/v) HNO(3) as the only required pre-treatment was shown to prevent contamination of the sample introduction system and to reduce polyatomic interferences from sample components. The origin of the blank signal at masses of gallium isotopes, 71 and 69, was investigated using high-resolution ICP-MS and attributed, respectively, to the formation of (36)Ar(35)Cl(+) and (40)Ar(31)P(+) ions and, tentatively, to a triplet of doubly charged ions of Ba, La, and Ce. The accuracy and precision performance was tested by evaluating a set of parameters for analytical method validation. The developed assay has been applied for the determination of gallium in urine samples spiked with GaQ(3). The achieved recoveries (95-102%) and quantification limit of 0.2 µg L(-1) emphasize the practical applicability of the presented analytical approach to monitor renal elimination of GaQ(3) at all dose levels in clinical trials that are currently in progress.


Assuntos
Antineoplásicos/metabolismo , Gálio/urina , Espectrometria de Massas/métodos , Compostos Organometálicos/metabolismo , Oxiquinolina/análogos & derivados , Gálio/metabolismo , Humanos , Limite de Detecção , Oxiquinolina/metabolismo
16.
Appl Spectrosc ; 72(2): 199-208, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28862021

RESUMO

A new algorithm for the evaluation of the integral line intensity for inferring the correct value for the temperature of a hot zone in the diagnostic of combustion by absorption spectroscopy with diode lasers is proposed. The algorithm is based not on the fitting of the baseline (BL) but on the expansion of the experimental and simulated spectra in a series of orthogonal polynomials, subtracting of the first three components of the expansion from both the experimental and simulated spectra, and fitting the spectra thus modified. The algorithm is tested in the numerical experiment by the simulation of the absorption spectra using a spectroscopic database, the addition of white noise, and the parabolic BL. Such constructed absorption spectra are treated as experimental in further calculations. The theoretical absorption spectra were simulated with the parameters (temperature, total pressure, concentration of water vapor) close to the parameters used for simulation of the experimental data. Then, spectra were expanded in the series of orthogonal polynomials and first components were subtracted from both spectra. The value of the correct integral line intensities and hence the correct temperature evaluation were obtained by fitting of the thus modified experimental and simulated spectra. The dependence of the mean and standard deviation of the evaluation of the integral line intensity on the linewidth and the number of subtracted components (first two or three) were examined. The proposed algorithm provides a correct estimation of temperature with standard deviation better than 60 K (for T = 1000 K) for the line half-width up to 0.6 cm-1. The proposed algorithm allows for obtaining the parameters of a hot zone without the fitting of usually unknown BL.

17.
Talanta ; 187: 370-378, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29853061

RESUMO

A scheme of determination of As, Bi, Hg, Sb, Se and Te with photochemical generation of their volatile derivatives and inductively coupled plasma mass spectrometry (ICP-MS) detection was developed. The volatile compounds were produced using a novel photochemical reactor with direct contact of a sample with an ultraviolet (UV) lamp. Essential experimental parameters such as the concentrations of the reagents and the flow rates of the carrier gas and the sample were optimized. For each element, individual optimum values of these parameters were obtained. The detection limits in the optimal single element modes for As, Bi, Hg, Sb, Se and Te were 0.5, 13, 0.6, 0.3, 0.4 and 0.7 ng L-1 respectively. Compromise conditions were determined for simultaneous multielement analysis. The increase of the detection limit for each element in the multielement mode was experimentally estimated. The applicability of the proposed scheme was demonstrated by analysis of certified reference samples of water and fish muscle. Acceptable accuracy of determination of As, Se, Sb, Te and Hg in samples of local lake water was proved by spike recovery test. Possible matrix effects were screened using Placket-Berman design and further examined in detail.

18.
J Inorg Biochem ; 137: 40-5, 2014 08.
Artigo em Inglês | MEDLINE | ID: mdl-24803025

RESUMO

Binding to plasma proteins is one of the major metabolic pathways of metallodrugs. In the case of platinum-based anticancer drugs, it is the interaction with serum albumin that affects most strongly their in vivo behavior. Since both the configuration, i.e. cis-trans-isomerism, and the nature of leaving groups have an effect on the reactivity of Pt(II) coordination compounds toward biomolecules, a set of cis- and trans-configured complexes with halide leaving groups (Cl(-), Br(-), and I(-)) and 2-propanone oxime as carrier ligands was chosen for this study. Binding experiments were performed both with albumin and human serum and the Pt content in ultrafiltrates was quantified using inductively coupled plasma mass spectrometry. In order to shed light on the binding mechanism, the albumin binding constant (KHSA) and the octanol-water partition coefficient (P) were experimentally determined and relationships between log KHSA and log P were explored. The correlation was found significant only for cis-configured platinum complexes (R(2)=0.997 and standard deviation=0.02), indicating a certain contribution of the nonspecific binding which is largely dominated by the lipophilicity of compounds. In contrast, for trans-complexes a specific molecular recognition element plays a significant role. The participation of albumin in drug distribution in blood serum was assessed using an equilibrium distribution model and by comparing the percentage binding in the albumin and serum-protein fractions. Irrespective of the compound polarity, albumin contributes from 85 to 100% to the overall binding in serum.


Assuntos
Antineoplásicos/química , Proteínas Sanguíneas/química , Compostos de Platina/química , Albumina Sérica/química , Antineoplásicos/administração & dosagem , Proteínas Sanguíneas/metabolismo , Desenho de Fármacos , Humanos , Isomerismo , Ligantes , Espectrometria de Massas , Platina/sangue , Platina/química , Compostos de Platina/sangue , Compostos de Platina/metabolismo , Ligação Proteica , Albumina Sérica/metabolismo
19.
Anal Chim Acta ; 785: 22-6, 2013 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-23764439

RESUMO

The application of an inductively coupled plasma mass spectrometry (ICP-MS) assay for quantifying in vitro binding of a gallium-based anticancer drug, tris(8-quinolinolato)gallium(III), to serum albumin and transferrin and in human serum is described. The distribution of the drug between the protein-rich and protein-free fractions was assessed via ICP-MS measurement of total gallium in ultrafiltrates. Comparative kinetic studies revealed that the drug exhibits a different reactivity toward individual proteins. While the maximum possible binding to albumin (~10%) occurs practically immediately, interaction with transferrin has a step-like character and the equilibrium state (with more than 50% binding) is reached for about 48 h. Drug transformation into the bound form in serum, also very fast, results in almost quantitative binding (~95%). The relative affinity of protein-drug binding was characterized in terms of the association constants ranging from 10(3) to 10(4)M(-1). In order to further promote clinical testing of the gallium drug, the ICP-MS method was applied for direct quantification of gallium in human serum spiked with the drug. The detection limit for gallium was found to be as low as 20 ng L(-1). The repeatability was better than 8% (as RSD) and the achieved recoveries were in the range 99-103%.


Assuntos
Antineoplásicos/metabolismo , Proteínas Sanguíneas/metabolismo , Espectrometria de Massas , Compostos Organometálicos/metabolismo , Oxiquinolina/análogos & derivados , Antineoplásicos/química , Proteínas Sanguíneas/química , Humanos , Cinética , Compostos Organometálicos/química , Oxiquinolina/química , Oxiquinolina/metabolismo , Ligação Proteica , Albumina Sérica/química , Albumina Sérica/metabolismo , Transferrina/química , Transferrina/metabolismo
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