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EN
Due to the wide applicability of separation techniques that rely on the property of differential migration in pharmaceutical formulations analysis, different analytical strategies have been proposed to resolve mixtures of multi-components pharmaceuticals. Three separation methods were developed and validated for the simultaneous determination of Paracetamol (PAR), Pseudoephedrine HCl (PSE) and Chlorpheniramine maleate (CHP). The first method is a thin-layer chromatographic (TLC) separation, followed by densitometric measurement. The separation was carried out on aluminium sheet of silica gel 60 F254 using ethanol:chloroform:ammonia (1:7:0.4, by volume) as the mobile phase. Determination of PAR, PSE and CHP was successfully applied over the concentration ranges of 3–25 µg/band, 0.5–10 µg/band and 0.1–6 µg/band, respectively. The second method is HPLC separation that was achieved on C18 column using the mobile phase acetonitrile:phosphate buffer pH 5 (10:90, v/v) at a flow rate 1 mL min⁻¹. PAR, PSE and CHP were determined by HPLC in concentration ranges of 5–400 μg mL⁻¹, 2–40 μg mL⁻¹ and 0.5–16 μg mL⁻¹, respectively. The third method is a capillary electrophoresis (CE) separation. The electrophoretic separation was achieved using 20 mM phosphate buffer (pH 6.5) at 20 kV. The linearity was reached over concentration ranges of 30–250 μg mL⁻¹, 5–50 μg mL⁻¹ and 0.8–20 μg mL⁻¹ for PAR, PSE and CHP, respectively. The developed methods were validated with respect to linearity, precision, accuracy and system suitability. The proposed methods were successfully applied for bulk powder and dosage form analysis with RSD of precision <2%. Moreover, statistical comparison with the official methods confirms the methods' validity.
EN
The analysis of milk and dairy products is essential during production, quality control, and understanding the factors that cause food allergies. Milk is one of many examples of biocolloids. Numerous studies show that capillary electrophoresis and capillary isoelectric focusing is an excellent tool for this type of analysis. In addition, the coupling of these techniques with other analytical methods such as MALDI-TOF MS or ESI-MS enables the improvement of the quality of analyzes, allows the separation of proteins close to the isoelectric point values. This short overview summarizes the possibilities of using electromigration techniques in the proteomic and microbiological analysis of milk and milk products.
EN
A simple capillary electrophoresis (CE) method with ultraviolet (UV) detection was developed for the determination of hexachlorophene (HCP) in cosmetics. Separation conditions were obtained in 20 mM Na2B4O7, 10% MeOH (pH 9.20), with 25 kV applied voltage and UV detection at 208 nm. Under the selected conditions, electrophoretic analysis was completed in about 4 min, with limit of detection (LOD) of 0.06 mg$mL1 for HCP. The method was successfully applied to determine HCP in three kinds of cosmetics with relative standard deviations (RSD) of 0.52–3.02% and recoveries from 90.0 to 96.4% for the spiked samples. The results indicated that the proposed method was reliable. Comparative experiments were also carried out with high-performance liquid chromatography (HPLC)-UV method described in National Standards of People’s Republic of China. The validation results of the two methods are comparable, but the proposed CE method is simple, rapid, which makes separation and analyte quantification in shorter time with much less reagent consumption.
EN
Surface active agents, also known as surfactants, are a group of chemical compounds that are used in various products of the chemical industry. These compounds are components of medicines, detergents, motor oils and many others. The multitude of uses of surfactants makes it important to know their aggregation behaviour in solution. There are many methods used to analyse surfactants behaviour in liquid phase. The choice of a particular technique usually depends on the chemical structure of the surfactant. An example of a method that is used in studies of ionic surfactants is conductometry. This technique allows to study the dependence of specific conductivity on surfactant concentration, enabling determination of critical micellar concentration (CMC). Capillary electrophoresis is another example of the method used to determine the critical micellar concentration. It allows to make measurements in conditions where other methods fail, including conductometric method. Surfactant solutions differ in viscosity, which changes with the appearance of micelles in solution. Measurement of marker compound migration time through surfactant solutions of various concentrations allow to determine critical micellar concentration. Isothermal titration calorimetry (ITC) allows to study the thermal effects associated with the aggregation of surfactants into micelles. Based on the energy changes that occur during titration, the critical micellar concentration of surfactant can be precisely determined. ITC is very sensitive method, so basically it can be used to examine all types of surfactants. In addition, the ITC method allows to determine the thermodynamic parameters of the undergoing micellization process. The use of several measuring methods gives a more complete picture of the phenomena occurring in solutions. It allows to understand aggregation process more accurately. Therefore, CMC measurement are often made with the use of several complementary methods.
PL
Zastosowano metodę elektroforezy kapilarnej (CE) do oznaczenia jakościowego i ilościowego jonów: ClO3-, ClO4-, NO3-, NH4+,K+ w pozostałościach po przemianie wybuchowej materiałów pirotechnicznych.Po wybuchu petardy hukowej FP3 i petardy wojskowej pobrano próbki gleby z miejsca wybuchu i poddano je ekstrakcji, a następnie analizie metodą CE. Wyznaczone granice oznaczalności wynosiły od 0,78 mg/l dla K+ do 3,12 dla NO-. Metoda CE pozwoliła na rozróżnienie materiałów pirotechnicznych na podstawie oznaczenia wybranych jonów w pozostałościach po wybuchu.
EN
Capillary electrophoresis (CE) method was applied for qualitative and quantitative determination ClO3-, ClO4-, NO3-, NH4+,K+ , in pyrotechnic materials after explosive transformation. After ex- plosion of fire-cracker with black powder and military fire-cracker, soil samples from explosion area were collected, extracted and analyzed by CE method. Determined limits of quantifications were from 0.78 mg/L for K+ to 3.12 for NO-. The CE method allowed to distinguish pyrotechnic materials on the basis of selected ions determination in pyrotechnic materials residues.
6
Content available Metody oznaczania barwników spożywczych
EN
Food dyes are chemical substances that were developed to enhance the appearance of food by giving it artificial color. People have added colorings to food for centuries, but the first artificial food colorings were created in 1856 from coal tar. Over the years, hundreds of artificial food dyes have been developed, but a majority of them have since been found to be toxic. There is only a handful of artificial dyes that are still used in food. Food manufacturers often prefer artificial food dyes over natural food colorings, such as beta carotene and beet extract, because they produce a more vibrant color [1]. However, there is quite a bit of controversy regarding the safety of artificial food dyes. All of the artificial dyes that are currently used in food have gone through testing for toxicity in animal studies. Regulatory agencies, like the US Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA), have concluded that the dyes do not pose significant health risks. Not everyone agrees with that conclusion. Interestingly, some food dyes are deemed safe in one country, but banned from human consumption in another, making it extremely confusing to assess their safety [2]. Undesirable effects of azo dyes used for coloring food products led to the development of very sensitive and selective analytical methods successfully used for their determination in various food matrices. Many different methods have been employed for the determination of synthetic dyes in food and beverages including thin layer chromatography and capillary electrophoresis [3]. However, these methods can be time consuming and may not be applicable for the simultaneous analysis of many dyes. Conventional HPLC methods have been employed for the analysis of synthetic colorants and while useful, these methods require long analysis times and large amounts of expensive solvents [4, 5]. Preparation of the test sample involves the use of various techniques such as membrane filtration due to the complexity of food products. Therefore, the development of simple, selective extraction methods together with the combination of chromatographic and spectrophotometric techniques are of great importance [6]. One of the most difficult stages of the analysis is the appropriate selection of the method for the determination of food colors. In the case of spectrophotometric methods, the main advantage is the low cost of the determination, however, the lack of specificity of the absorption spectrum usually makes it difficult to apply this method in the case of a mixture of different absorbing dyes due to the overlap of the spectra. The CE (Capillary Electrophoresis) analysis is faster and more economical compared to conventional electrophoresis and chromatography. The production of cheap capillaries and the development of on-line detection systems contributed to the development of modern capillary electrophoresis. Capillary electrophoresis has a number of types of separation. Ultimately, it is impossible to determine the one particular appropriate specific method for the determination of food dyes due to their diverse structure and chemical composition [4, 7].
PL
Artykuł powstał na podstawie nagrodzonej w 2017 roku przez Komitet Chemii Analitycznej PAN pracy doktorskiej. Nagroda za najlepszą pracę związaną z rozwojem technik rozdzielania sponsorowana jest przez firmę Perlan Technologies. Promotorem pracy doktorskiej był prof. Paweł Kościelniak a promotorem pomocniczym dr Michał Woźniakiewicz.
PL
Artykuł powstał na podstawie nagrodzonej w 2017 roku przez Komitet Chemii Analitycznej PAN pracy doktorskiej. Nagroda za najlepszą pracę związaną z rozwojem technik rozdzielania sponsorowana jest przez firmę Perlan Technologies. Promotorem pracy doktorskiej był prof. Paweł Kościelniak, a promotorem pomocniczym dr Michał Woźniakiewicz.
EN
Unfortunately, despite of work involved in understanding of the mechanism of bacterial virulence, especially Staphylococcus aureus, it has not been developed effective therapy against this bacteria. The first antibiotic used against this bacteria was penicillin, which was discovered by Alexander Fleming in 1928. A new generation of drugs introduced into therapy against Staphylococcus aureus and other Gram-positive bacteria are glycopeptide antibiotics. The most widespread and most commonly used are vancomycin and teicoplanin, discovered respectively in 1956 and 1978. As a result of frequent use of vancomycin VISA (ang. Vancomycin-intermediate Staphylococcus aureus) and VRSA (ang. Vancomycin-resistant Staphylococcus aureus) strains were discovered. The mechanism of action of this antibiotic based on the inhibition of the biosynthesis of bacterial cell wall peptidoglycan fragment. Forming stabilized by hydrogen bonds complex with terminal fragment of peptidoglycan (dipeptide d-Ala-d-Ala) vancomycin prevents its further crosslinking [2] (Fig. 1). However, in recent years other theories of the mechanism of action of glycopeptide antibiotics against Gram-positive bacteria were presented it seems to be crucial to find methods of selection of new antibiotics and for this purpose standard techniques of the analysis, including isothermal titration calorimetry (ITC) [3], nuclear magnetic resonance spectroscopy (NMR) [8–15], high performance liquid chromatography (HPLC) [16], capillary electrophoresis [17] or self-assembled monolayers (SAMs) [22] are used. Discovering new methods for studying of interaction between vancomycin and Gram-positive bacterial cell wall allows use it as a new technique for rapid selection of potential new antibiotics, including glycopeptide derivatives.
PL
Przedstawiono proces immobilizacji syntetycznego inhibitora proteaz serynowych AEBSF, który należy do rodziny związków benzosulfonowych. Zastosowanie techniki elektroforezy kapilarnej do celów analizy ilościowej pozwoliło na przeprowadzenie szybkiego pomiaru, charakteryzującego się wysoką specyficznością i precyzją. Na podstawie uzyskanych wyników stwierdzono, że inhibitor AEBSF, poddawany procesowi kowalencyjnej immobilizacji, jest efektywnie wiązany do porowatego nośnika. Jednocześnie określono, że wiąże się on z matrycą także wiązaniami adsorpcyjnymi i hydrofobowymi.
EN
The paper describes a method of immobilization of AEBSF synthetic protease inhibitor which belongs to the family of benzensulfonyl compounds. The application of capillary electrophoresis for a quantitative analysis allows one to perform high-speed measurement characterized by high specificity and repeatability. The obtained results allowed one to confirm that the AEBSF inhibitor under covalent immobilization process is effectively bound to the porous support. It was also determined that AEBSF inhibitor binds to the matrix by adsorption and hydrophobic bonds.
EN
Quinolinium and pyridinium salts belong to the group of onium compounds and are widely used in organic, structural and analytical chemistry. Their synthesis is mainly based on quaternization of the nitrogen atom in a heterocyclic ring [4, 13, 23]. In analytical chemistry quinolinium and pyridinium salts such as 2-chloro-1-methylquinolinium tetrafluoroborate (CMQT) or 1-benzyl-2-chloropyridinium bromide (BCPB) perform very well as thiol specific derivatization reagents in terms of derivatization reaction velocity, stability, chromatographic properties of the derivatives, and thus, amenability to automatization [18–22, 32–42]. Analytical procedures for thiol determination usually involve reduction of disulfide bonds with tris(2-carboxyethyl)phosphine, tri-n-butylphosphine or mercaptoethanol, chemical derivatization of the sulfur compound with the use of 2-halopyridinium or 2-haloquinolinium salts and then deproteinization, followed by ion-pair reversed-phase HPLC or CE separation and spectrophotometric detection. Derivatization reaction takes advantage of great susceptibility of quinolinium or pyridinium molecules at 2-position to nucleophilic displacement, and a high nucleophilicity of the thiol group. Derivatization reaction mixture is usually ready to be analyzed just after mixing of the substrates. CMQT and BCPB exhibit very high reactivity toward thiols [44, 45], sulfides [63] as well as thiosulfates [40, 54]. 2-S-quinolinium and 2-S-pyridinium derivatives possess advantageous spectrophotometric and chromatographic properties. They are stable and more hydrophobic than thiols themselves, possessing a well-defined absorption maximum in the UV region. The reaction is accompanied by an analytically advantageous bathochromic shift from reagent maximum to the maximum of the derivative. Thanks to this phenomenon it is possible to use a large excess of derivatization reagent in order to drive the reaction to completion and avoid a huge signal of unreacted compound on the chromatogram [26]. Elaborated with the use of onium salts methods have proven to be useful in quantitative HPLC and CE analysis of endogenous and exogenous low-molecular-weight biological thiols in human body fluids, plant extracts and some groceries [44, 45].
PL
Ciecze jonowe (ang. Ionic Liquids, ILs) z uwagi na swoje unikalne właściwości fizyko – chemiczne oraz możliwość prostej modyfikacji budowy, w znacznym stopniu przyczyniły się do rozwoju technik rozdzielania. W chromatografii gazowej fazy stacjonarne w postaci cieczy jonowych stanowią istotne uzupełnienie istniejących faz stacjonarnych na bazie polisiloksanów i glikolu polietylenowego. Ze względu na wysoką stabilność termiczną oraz wysoką polarność umożliwiają selektywne rozdzielenie szerokiej gamy związków. W chromatografii cieczowej, wykorzystywane są do modyfikacji faz ruchomych w celu tłumienia szkodliwych oddziaływań silanolowych, jak również do pokrywania krzemionkowych faz stacjonarnych dla zapewnienia wysokiej rozdzielczości badanych związków. W technikach elektroforetycznych ciecze jonowe stosuje się głównie jako dodatki do buforu podstawowego dla zwiększenia selektywności związków hydrofobowych.
EN
Ionic liquids (ILs) due to their unique physical and chemical properties and the possibility of a simple modification of their composition, have significantly contributed to the development of separation techniques. In gas chromatography the ionic liquids as stationary phases are an important supplement to the existing stationary phases based on polysiloxanes and polyethylene glycol. Due to its high thermal stability and high polarity they allow selective separation of a wide variety of compounds. In liquid chromatography Ils are used to modify the mobile phase to suppress the harmful silanol effects, as well as the coating of the silica stationary phase for high-resolution of test compounds. In electrophoretic techniques, ionic liquids are used mainly as additives in the buffer to increase the selectivity of the basic hydrophobic compounds.
EN
Comparison of classical densitometry, video-scanning, and capillary electrophoresis was performed for determination of angiotensin II receptor antagonist, valsartan, and calcium channels blocker, amlodipine, in a combined dosage form. Thin layer chromatography was performed on RP8F254 TLC plates with a mobile phase consisting of acetonitrile-phosphate buffer at pH 9.0 (5:5, v/v) and temperature 20 °C. Densitometry was done in the reflectance mode at 217 nm for valsartan and in the absorbance mode at 370 nm for amlodipine. Video-scanning was elaborated at 254 and 366 nm for valsartan and amlodipine, respectively. For chromatographic analysis, calibration plots were constructed in the range of 0.4–2.8 μg per spot for valsartan and 0.02–0.14 μg per spot for amlodipine. Capillary electrophoresis (CE) was performed using a 75 μm × 94 cm fused silica capillary (72 cm effective length), 0.01 mol L-1 borate buffer at pH 8.0, 20 kV voltage, 30 °C temperature, hydrodynamic injection (10 mbar, 6 s) and UV detection at 237 nm. Calibration plots were constructed in the range of 0.1–0.6 mg mL-1 for valsartan and 0.005–0.03 mg mL-1 for amlodipine. All methods were validated in respect to robustness, specificity, stability, linearity, precision, and accuracy. Generally, statistical comparison between the methods did not show significant differences so all procedures are suitable for pharmaceutical analysis.
14
Content available remote Wysokosprawne rozdzielenia elektroforetyczne w analizie farmaceutycznej
PL
Przedstawiono nowe rozwiązania analityczne dostępne dzięki zastosowaniu elektroforezy kapilarnej, pozwalające zarówno na analizę jakościową, jak i ilościową substancji aktywnych leków oraz badanie ich zanieczyszczeń chiralnych, a także nieorganicznych. Wysokie możliwości rozdzielcze, krótki czas analiz oraz znaczna elastyczność pomiarów sprawia, że elektroforeza kapilarna staje się techniką stosowaną w przemyśle farmaceutycznym równie powszechnie, jak wysokosprawna chromatografia cieczowa (HPLC). Omówione przykłady pokazują możliwości użycia unikatowych mechanizmów rozdzielania elektroforetycznego w analizie substancji aktywnych.
EN
A review, with 63 refs., of anal. methods based on capillary electrophoresis used for qual. and quant. detn. of active pharmaceutical substances, inorg. impurities and chiral species.
PL
Elektroforeza kapilarna (CE) to metoda analityczna o bogatej historii. Jest popularna w laboratoriach ze względu na swój ekologiczny charakter, niezawodność, wygodę, możliwość zastosowania w skali mikro. Jest systemem badawczym komplementarnym i alternatywnym w stosunku do wysokosprawnej chromatografi i cieczowej (HPLC).
EN
Capillary electrophoresis (CE) is an analytical method with a rich history. It is popular in laboratories due to its ecological character, reliability, convenience and possibility of micro-scale use. This is a technique that is complementary alternative to high performance liquid chromatography (HPLC).
PL
Wykonano analizę wybranych lotnych związków organicznych w czterech napojach orzeźwiających metodą chromatografii gazowej ze spektrometrią mas. Dodatkowo zbadano zawartość wybranych anionów nieorganicznych oraz organicznych we wspomnianych napojach metodą elektroforezy kapilarnej. Lotne związki organiczne wyizolowano z fazy nadpowierzchniowej napojów techniką mikroekstrakcji do fazy stacjonarnej. We wszystkich próbkach wykryto D-limonen, odpowiedzialny za aromat cytrynowy.
EN
Gas chromatography-mass spectrometry method was applied for selected volatile organic compounds analysis of four similar refreshing drinks. The presence of selected inorganic and organic anions in mentioned drinks were additionally determined by capillary electrophoresis method. Solid phase microextraction was applied to isolate volatile organic compounds from drinks head space. D-limonene, responsible of lemon flavour, was determined in all samples.
PL
Celem niniejszej pracy było określenie, czy krenoterapia (kuracja pitna) za pomocą wód siarczkowo- siarkowodorowych słonych (WSSS) pochodzących z ujęcia "Zuzanna" z okolic Buska-Zdroju ma wpływ na zmianę stężenia glutationu (GSH i GSSG) we krwi pełnej. WSSS zawierają nie mniej niż 1 g związków siarki ogólnej w kilogramie wody leczniczej, a ich działanie zależy nie tylko od zawartości związków siarki, ale także od rodzaju i zawartości innych biopierwiastków. Liczne badania potwierdzają korzystny wpływ H2S na parametry antyoksydacyjne organizmu. W analizie stężenia GSH i GSSG we krwi wykorzystano metodę elektroforezy kapilarnej z detektorem UV. Badaniu poddano grupę 40 ochotników, zarówno kobiet jak i mężczyzn, w różnych przedziałach wiekowych. Kuracja za pomocą WSSS trwała 2 tygodnie. Otrzymane wyniki badań potwierdzają, że H2S występujący w WSSS zwiększa stężenie glutationu we krwi, a także dają uzasadnienie dla wykorzystywania krenoterapii w lecznictwie.
EN
The objective of the study was to agree whether crenotherapy (drinking therapy) with sulfide/hydrogen sulfide (SHS) waters from "Zuzanna" spring located in the area of Busko-Zdrój leads to increasing of glutathione (GSH and GSSG) content in human blood. SHS waters contain at least 1 g of total sulfur per kilogram of water and a treatment effect also depends on other bioelements. A lot of earlier experiments confirmed positive influence of H2S on antioxidative properties of organism. The method employing capillary electrophoresis with UV detector for the analysis of glutathione in human blood was developed. The group of 40 volunteers consisted of both women and men, in different age range. The therapy with SHS waters lasted 2 weeks. We recently demonstrated that the administration of H2S in SHS waters increases GSH concentration in blood, and therefore crenotherapy could be used in therapeutics.
EN
An ultrasensitive and rapid method for the determination of epicatechin, rutin, and quercetin was developed using capillary zone electrophoresis with on-line chemiluminescence detection. Under the optimal conditions, the analytes were baseline separated within 12 min. The limits of detection in turn were 0.60 pg mL-1 for epicatechin, 0.50 pg mL-1 for rutin, and 1.0 pg mL-1 for quercetin. The developed method was an easy and reliable method of determining these analytes concentrations in tea, extract Ginkgo biloba, and rutin tablet, demonstrating the feasibility and reliability of the proposed method.
EN
This study reports the effect of a nonionic perfluorinated surfactant, N-polyoxyethylene-N-propyl perfluorooctane sulfonamide (PFOSA), as additive of background electrolyte on capillary electrophoresis (CE) of common inorganic cations. The association constants (Kass) for PFOSA estimated from the electrophoretic mobility of analyte cations were the order of Mg2+ > Ca2+ > Sr2+ > K+ ≈ NH4+ > Na+ ≈ Li+. The Kass values were larger than those for zwitterionic and nonionic surfactants with hydrocarbon moiety. Use of PFOSA made another essential contribution to the determination of inorganic cations in a protein-containing sample. This was considered because high solubility of PFOSA for proteins functioned as suppressor for protein adsorption to the capillary wall. Four inorganic cations, Na+, K+, Mg2+, and Ca2+, in human saliva sample were successfully determined by sample injection without any pretreatments except for filtration and dilution.
EN
Formaldehyde in aquatic products was determined by micellar electrokinetic capillary chromatography (MEKC) after derivatization with 2,4-dinitrophenylhydrazine. Separation was carried out at 25 °C and 25 kV, using a fused silica capillary (75 µ internal diameter; 50.5 cm effective length) and an ultraviolet detector set at 360 nm. The optimal background electrolyte was 20 mM sodium tetraborate and 20 mM sodium dodecyl sulfate at pH 9.0 with 3 s hydrodynamic injection at 30 mbar. Electrophoretic analysis took approximately 6.5 min. The correlation coefficient of the calibration curve was 0.999 over the concentration range 2.0–100.0 mg L-1 and the LOD and LOQ values were 0.57 and 1.89 µg mL-1, respectively. The recoveries were from 83.7% to 97.2% with steam distillation as the sample pretreatment method.
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