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1

Analysis of neurotransmitter catecholamines and related amines in human urine and serum by chromatography and capillary electrophoresis with 1, 3, 5, 7-tetramethyl-8-(N-hydroxysuccinimidyl propionic ester)-difluoro-boradiaza-s-indacene

Cao Liwei, Wu Lizhen, Zhong Hailan, Wu Hao, Zhang Siyun, Meng Jianxin, Li Fengyu

Acta Chromatographica

|

2022

|

Vol. 34, no. 3

276--286

EN

Two sensitive and effective methods were developed for the detection of catecholamines and related biogenic amines (dopamine, epinephrine, norepinephrine, serotonin, levodopa and tyramine) using high performance liquid chromatography with fluorescence detection and capillary electrophoresis with laser-induced fluorescence detection. A BODIPY fluorescent dye, 1, 3, 5, 70-tetramethyl-8-(N-hydroxysuccinimidyl propionic ester)-difluoroboradiaza-s-indacene was used as pre-column derivatization reagent. The separation and derivatization conditions were optimized in detail. In high performance liquid chromatography with fluorescence detection method, the derivatization reaction was completed at 35 °C for 20 min. At the wavelength of λex/λem = 493 nm/513 nm, dopamine, epinephrine, norepinephrine, and levodopa derivatives achieved baseline separation within 15 min. The limits of detection (S/N = 3) were 1.0, 2.0, 5.0, and 0.5 nmol/L, respectively. In capillary electrophoresis with laser-induced fluorescence detection method, the derivatization reaction was completed at 25 °C for 20 min. Serotonin, tyramine and dopamine derivatives reached baseline separation within 10 min at the wavelength of λex = 473 nm. The limits of detection (S/N = 3) for serotonin, tyramine, and dopamine were 0.3, 0.02, and 0.2 nmol/L, respectively. The amino compounds in human serum and urine samples were detected successfully, and the recoveries were 93.3%–106.7% and 91.0%–103.1%, respectively.

2

Derywatyzacja w chromatografii gazowej. Przegląd metod i reagentów

Haliński Łukasz

Laboratorium - Przegląd Ogólnopolski

|

2020

|

nr 3

14--21

PL

Synteza pochodnych (derywatyzacja) to kluczowy etap wielu metod analitycznych wykorzystujących chromatografię gazową. Pozwala na zwiększenie lotności oraz stabilności termicznej analitów, a także ułatwia identyfikację substancji. W artykule przedstawione są najważniejsze metody syntezy pochodnych oraz przegląd powszechnie stosowanych reagentów. Wskazane są także możliwe drogi rozwoju analityki w tym obszarze.

EN

Derivatization is a key stage of many analytical procedures that utilize gas chromatography as an analytical technique. lt enables increasing the volatility and thermal stability of analytes, and sometimes facilitates their identification. The most important methods of derivatization and widely used reagents are described in this short review. Perspectives of the further progress in this field are also briefly discussed.

3

Liquid phase microextraction techniques combined with chromatography analysis: a review

Dugheri Stefano, Mucci Nicola, Bonari Alessandro, Campagna Marcello, Montalti Manfredi, Arcangeli Giulio, Ubiali Daniela, Marrubini Giorgio, Cappelli Giovanni

Acta Chromatographica

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2020

|

Vol. 32, no. 2

69--79

EN

Sample pretreatment is the first and the most important step of an analytical procedure. In routine analysis, liquid–liquid microextraction (LLE) is the most widely used sample pre-treatment technique, whose goal is to isolate the target analytes, provide enrichment, with cleanup to lower the chemical noise, and enhance the signal. The use of extensive volumes of hazardous organic solvents and production of large amounts of waste make LLE procedures unsuitable for modern, highly automated laboratories, expensive, and environmentally unfriendly. In the past two decades, liquid-phase microextraction (LPME) was introduced to overcome these drawbacks. Thanks to the need of only a few microliters of extraction solvent, LPME techniques have been widely adopted by the scientific community. The aim of this review is to report on the state-of-the-art LPME techniques used in gas and liquid chromatography. Attention was paid to the classification of the LPME operating modes, to the historical contextualization of LPME applications, and to the advantages of microextraction in methods respecting the value of green analytical chemistry. Technical aspects such as description of methodology selected in method development for routine use, specific variants of LPME developed for complex matrices, derivatization, and enrichment techniques are also discussed.

4

Derywatyzacja in situ w połączeniu z techniką DLLME - oznaczanie amin biogennych w winach owocowych

Płotka-Wasylka J., Kłodzińska E., Namieśnik J.

Analityka : nauka i praktyka

|

2018

|

nr 2

54--59

PL

Pomimo braku oficjalnych dokumentów wprowadzających obligatoryjność oznaczania AB w wyrobach winiarskich istnieje szereg wymagań dla importerów w UE, które wyznaczają limity stężeń poszczególnych AB w winie

5

Derywatyzacja chemiczna w wysokosprawnej chromatografii cieczowej

Kamińska A., Krawczyk M. J., Chwatko G.

Wiadomości Chemiczne

|

2016

|

[Z] 70, 11-12

771--802

EN

High performance liquid chromatography (HPLC) is a method used to determine inorganic and organic substances in biological samples. Nevertheless, many analytes cannot be detected using HPLC method, because they do not contain a necessary chromophoric or fluophoric groups. Derivatization is the solution of this problem. This process can be defined as a conversion of analyte to corresponding derivative which possesses in its structure a moiety compatible with suitable detector [1, 2]. Reagent responsible for conversion of analyte to a derivative needs to meet a lot of requirements. It needs to be selective e.g. to react only with analysed substances and it should not generate by-products. The derivatization reagent should react rapidly, quantitatively, at lowest possible temperature and weakly pH, and the excess of reagent should be easily removable from reaction medium [1, 3, 5]. The derivatization can be carried out in pre-column, post-column and on-column mode. In the pre-column derivatization, analytes are derivatized before injection on HPLC system, and the reaction products are separated and detected. In the post-column derivatization, the reaction is performed automatically by adding the derivatization reagent after separation but before detection. The third method is based on reaction, which simultaneously proceeds with column separation [2, 3, 5, 6]. The derivatization processes in gas and liquid chromatography are subject matter among researcher from all over the world. The Polish literature has only few review articles on derivatization process in liquid chromatography [2, 4, 55]. The present article reviews derivatization techniques used in HPLC. Derivatization techniques used in gas chromatography are classified due to the chemical nature of derivatization reagent [3, 56]. Our attention is focused on the analyte and derivatization reagent, which can be react with various functional groups such as amino, sulfhydryl, hydroxyl or carboxyl groups, occurring in the examined molecules. By chemically modification compounds into derivatives, they obtain necessary properties for chromatographic separation and accurate analysis.

6

Derywatyzacja analitów - sposób na poprawę skuteczności procesu rozdzielania chromatograficznego

Płotka J., Morrison C., Biziuk M., Namieśnik J.

Analityka : nauka i praktyka

|

2015

|

nr 3

4--13

PL

Wiele badanych związków nie wykazuje takich właściwości, aby możliwe było ich oznaczanie przy użyciu technik chromatograficznych sprzężonych z danym typem detekcji, dlatego też konieczne staje się przeprowadzenie analitów w odpowiednie pochodne o pożądanych właściwościach umożliwiających ich oznaczenie, czyli przeprowadzenie tak zwanego procesu derywatyzacji.

7

Determination of Aldehydes in Wet Deposition

Czaplicka M., Jaworek K., Wochnik A.

Archives of Environmental Protection

|

2014

|

Vol. 40, no. 2

21--31

EN

The paper presents two sample preparation procedures for the determination of aldehydes in wet deposition. In both cases the 2,4-dinitrophenylhydrazine derivatization and solid phase extraction were applied. The derivatization in method A was applied before the extraction, the extraction in method B was carried out with simultaneous derivatisation. Accuracy of both methods was evaluated on the basis of the analysis of aqueous solutions of selected carbonyl compounds. Both methods were characterized by good recovery, however, due to the precision of the method expressed as RSD for testing of environmental samples the method B was used. The analysis of environmental samples showed significant differences in the concentrations of aldehydes in wet deposition, depending on the location of the sampling point. In the case of samples taken from agricultural areas the predominant aldehydes were formaldehyde and acetaldehyde. Formaldehyde was from 31% to 47% of the determined compounds. While in samples collected near a traffic source, in the deposition acrolein was determined at the levels from 62% to 64% of the identified compounds.

PL

W pracy przedstawiono dwie procedury przygotowania próbek mokrej depozycji do oznaczeń aldehydów. W obydwóch przypadkach zastosowano derywatyzację 2,4-dinitrofenylohydrazyną oraz ekstrakcję do fazy stałej. W metodzie A derywatyzacja poprzedzała ekstrakcję, w metodzie B ekstrakcję prowadzono z równoczesną derywatyzacją. Na podstawie analiz wodnych roztworów wybranych związków karbonylowych oceniono precyzję obydwóch metod. Ze względu na odzysk oraz wartość względnego odchylenia do analiz próbek środowiskowych pobranych z obszarów silnie uprzemysłowionych i rolniczych wybrano metodę B. Analiza próbek środowiskowych wykazała znaczne zróżnicowanie stężeń aldehydów w mokrej depozycji w zależności od lokalizacji punktu pobierania próbek. W przypadku próbek pobranych z obszarów rolniczych dominującymi aldehydami były formaldehyd i acetaldehyd. Formaldehyd stanowił od 31% do 47% oznaczonych związków. Podczas gdy w próbkach pobranych w pobliżu źródeł komunikacyjnych w depozycji stwierdzono udział akroleiny w oznaczonych aldehydach na poziomie od 62% do 64% oznaczonych związków.

8

Analityka hormonów płciowych - problemy i wyzwania

Kozłowska-Tylingo K., Namieśnik J.

Analityka : nauka i praktyka

|

2014

|

nr 1

50--55

PL

W pracy przedstawiono informacje o przebiegu poszczególnych etapów procedur analitycznych oznaczania związków endokrynnych z grupy hormonów płciowych wraz z opisem trudności, które mogą się pojawić.

9

The derivatization and analysis of anticancer pharmaceuticals in the presence of tricyclic antidepressants by gas chromatography

Haliński Ł., Śmigiel D., Czerwicka M., Paszkiewicz M., Kumirska J., Stepnowski P.

Acta Chromatographica

|

2014

|

Vol. 26, no. 3

473--484

EN

The evaluation of several derivatization procedures for the gas chromatographic analysis of selected anticancer pharmaceuticals (cyclophosphamide, iphosphamide, flutamide, chlorambucil, and melphalan) in the presence of tricyclic antidepressants was carried out. Among the methods, concerning trimethylsilylation, tert-butyldimethylsilylation, and methylation, the most useful was methylation using (trimethylsilyl)diazomethane (TMSD), which is a safe alternative for the common reaction with diazomethane. Most of the anticancer drugs were unstable during derivatization using silylating agents, while antidepressants were stable in all tested conditions. Melphalan was the only compound, for which the results of all tested procedures were not satisfying. The TMSD-based procedure was validated, giving the results possibly suitable for the screening purposes in contaminated environmental samples.

10

Derywatyzacja postkolumnowa w detekcji z absorpcją UV/VIS

Kleimann J., Ruth K. M., Krienbühl H., Wiklak M.

Laboratorium - Przegląd Ogólnopolski

|

2012

|

nr 3-4

74--75

PL

Detekcja UV/VIS jest jedną z najbardziej czułych technik detekcji stosowanych w chromatografii przy oznaczaniu śladowych ilości substancji. Zdarza się, że bezpośrednia detekcja spektrofotometryczna nie spełnia wymagań odnośnie do czułości, selektywności oraz powtarzalności i wówczas pomocna staje się derywatyzacja. W artykule przedstawiono elastyczność pracy reaktora dla czterech typów reakcji postkolumnowych: stosowano reakcję ninhydryny z aminokwasami i szybkich reakcji derywatyzacji do oznaczania bromianów i chromu (VI).

EN

UV/VIS detection is one of the most sensitive detection techniques in trace-level chromatography. Sometimes, however, spectrophotometric detection lacks sensitivity, selectivity or reproducibility and chemical derivatizations are required. The flexibility of the reactor is demonstrated by optimizing four widespread post-column techniques: the relatively slow ninhydrin reaction with amino acids and the fast derivatizations of bromate and chromate (VI).

11

Determination of acidic pharmaceuticals in municipal wastewater by using solid-phase extraction followed by gas chromatography-mass spectrometry

Nosek K., Styszko K., Gołaś J.

Geomatics and Environmental Engineering

|

2012

|

Vol. 6, no. 3

45--60

EN

The appearance of pharmaceutical compounds and the need of their determination in an aquatic environment has become a subject of growing concern over recent years. This paper describes an application of a quantitative analytical method for the determination of selected nonsteroidal anti-inflammatory drugs: ketoprofen, naproxen, diclofenac and other newly emerging contaminants - triclosan and bisphenol A in influent and effluent from a wastewater treatment plant located in Kraków (Poland). Samples were isolated and preconcentrated by using the solid - phase extraction (SPE) technique, then eluat was derivatized with N-methy-N-(trimethylsilyl)-trifluoroacetamide (MSTFA) and analyzed by gas chromatography coupled with mass spectrometry. All of tested pharmaceuticals were present in the wastewater treatment plant effluent and influent at concentration ppt to ppb.

12

Gas chromatographic determination of parabens after in-situ derivatization and dispersive liquid-liquid microextraction

Prichodko A, Janenaite E, Smitiene V, Vickackaite V.

Acta Chromatographica

|

2012

|

Vol. 24, no. 4

589--601

EN

Dispersive liquid-liquid microextraction in combination with an in situ derivatization is suggested for parabens sampling and preconcentration. The derivatization was carried out with acetic anhydride under alkaline conditions maintained using di-potassium hydrogen phosphate. The effects of an extraction solvent type, extraction and disperser solvents volume, extraction time, and ionic strength of the solution on the extraction efficiency were investigated. Chlorobenzene containing n-hexadecane as internal standard was used as an extracting solvent and acetone was used as a disperser solvent. The calibration graphs were linear up to 10 mg mL-1, correlation coefficients were 0.997–0.999, enrichment factors were from 70 for methylparaben to 210 for butylparaben, and detection limits were 22, 4.2, 3.3, and 2.5 µg L−1 for methylparaben, ethylparaben, propylparaben, and butylparaben, respectively. Repeatabilities of the results were acceptable with relative standard deviations up to 11%. A possibility to apply the proposed method for parabens determination in water samples was demonstrated.

13

Quantification of triazine herbicides using chloroplasts in conjunction with thin-layer chromatography

Broszat M., Ernst H., Spangenberg B.

Environmental Biotechnology

|

2011

|

Vol. 7, No. 2

47-52

EN

We present a video-densitometric quantification method for the triazine herbicides atraton, terbumeton, simazine, atrazine and terbutylazine. Triazine herbicides were separated on silica gel using methyl-t-butyl ether, cyclohexane (1+1, v/v) as mobile phase. The quantification was based on a bioeffective-linked analysis using chloroplast and 2,6-dichlorophenolindophenol. Within 1-2 minutes HILL-reaction inhibitor substances show blue-grey zones on a pale yellowgreen background. To increase the contrast, the moist plate can be dipped into a solution of PEG-600 (10% PEG-600 in methanol) for 2s. Measurements were carried out using a 16 bit ST-1603ME CCD camera with 1.56 megapixels (from Santa Barbara Instrument Group, Inc., Santa Barbara, USA). A white LED was used for illumination purposes. The range of linearity covers more than one magnitude using the (1/R) - 1 expression data transformation. The method can be used for herbicide screenings in environmental samples, because not spectral sensitivity but herbicide activity is measured. The separation method is cheap, fast and reliable.

14

GC-MS determination of halogen derivatives of acetic acid

Kowalska M., Dudziak M.

Architecture Civil Engineering Environment

|

2011

|

Vol. 4, no. 3

117-120

EN

The number of haloacetic acids exhibit carcinogenic properties so their occurrence in drinking water makes them hazardous to human health. Both Polish and international regulations impose certain limitations on their levels in water. This study addresses determination of haloacetic acids by liquid-liquid extraction, derivatization and GC-MS. The inclusion of GC-MS is a modification of standard techniques for assaying haloacetic acids. The procedure used herein enabled the separation of a 5-component mixture of haloacetic acids and their quantitative analysis in water at a concentration range of 15-30 ?g/dm3, depending on a compound. The repeatability of the technique did not exceed 16%.

PL

Szereg kwasów halogenooctowych jest rakotwórcza, co sprawia, że ich obecność w wodzie do picia stanowi zagrożenie dla zdrowia. Przepisy krajowe jak i międzynarodowe ograniczają zawartość wybranych kwasów w wodzie. Niniejsza praca opisuje metodę oznaczania kwasów halogenooctowych przy pomocy ekstrakcji ciecz-ciecz, upochodnienia oraz GC-MS. Włączenie analizy GC-MS w szlak oznaczania kwasów halogenooctowych stanowi modyfikację standardowo wykorzystywanych metod. Przedstawiona procedura umożliwia rozdział 5 składnikowej mieszaniny kwasów halogenooctowych i ich oznaczenie ilościowe w wodach na poziomie stężeń od 15 do 30 ?g/dm3 w zależności od związku. Powtarzalność metody nie przekraczała 16%

15

Derywatyzacja w oznaczaniu lotnych alifatycznych kwasów monokarboksylowych (LAKM)

Wasielewska M., Banel A., Zygmunt B.

Analityka : nauka i praktyka

|

2010

|

nr 2

21-26

PL

Lotne alifatyczne małocząsteczkowe kwasy monokarboksylowe oznaczane są zazwyczaj za pomocą chromatografii gazowej sprzężonej z odpowiednio dobraną techniką detekcji.

16

Wykorzystanie derywatyzacji w analizie próbek biologicznych na zawartość aminotioli techniką wysokosprawnej chromatografii cieczowej z detekcją UV-Vis

Głowacki R.

Wiadomości Chemiczne

|

2009

|

[Z] 63, 11-12

1049-1071

EN

Thiols are chemically and biochemically very active components of the sulfur cycle of the natural environment. Low molecular-mass thiols, such as homocysteine, cysteine, cysteinylglycine and glutathione are critical cellular components that play numerous roles in metabolism and homeostasis, and are important in a variety of physiological and pathological processes [1, 2]. Plasma thiols are being investigated as potential indicators of health status and disease risk [3.8]. Because of high affinity to oxidation low-molecular-mass thiols exist in biological samples mostly as symmetrical, unsymmetrical and protein-bound disulfides. Thus, determination of total thiol content must comprise disulfide bond disruption step. A reducing agent is necessary both for the reduction of the sulfide bonds and to keep the thiol in a reduced form until start of derivatization. Most of thiols lack the structural properties necessary for the production of signals compatible with common HPLC detectors, such as UV absorbance and fluorescence. Therefore, an analyst must resort to derivatization for signal enhancement and labile sulfhydryl group blocking if fluorescence or UV-Vis detection methods are employed. Ultraviolet detection is less specific and less sensitive than fluorescence one, nevertheless, its sensitivity is sufficient for detection and quantitation of endogenous and exogenous thiols in biological samples in physiological and pathological conditions. Moreover, equipment for HPLC-UV analysis is often a part of an existing, standard instrumentation in hospital laboratories and staff is usually well experienced in its use. All methods, except those based on electrochemical and tandem-mass spectrometry detection, depend on pre- or post-column derivatization of thiols. Useful reagents must form thiol derivatives with sufficient absorption and/or fluorescent yield to measure thiols at trace concentrations. Furthermore, the ideal reagent should show no absorption and should react rapidly and specifically with thiols to form stable products. Numerous reagents are available for the thiol derivatization. A majority of the reagents can be classified by type of the reactive moiety into three categories: activated halogen compounds, disulfides, and compounds possessing maleimide moiety, and are reviewed with some experimental details in excellent works [36.41].

17

Easy and accurate determination of urea in milk, blood plasma, urine and selected diets of mammals by high-performance liquid chromatography with photodiode array detection preceded by pre-column derivatization

Czauderna M., Kowalczyk J.

Chemia Analityczna

|

2009

|

Vol. 54, No. 5

919-937

EN

An HPLC method with photodiode array detection for simple and rapid determination of urea in physiological fluids of domestic animals has been described. A physiological fluid (blood plasma, urine, or milk) was treated with 20% trichloroacetic acid and then the mixture was centrifuged. 200 &muL of the supernatant were derivatized using 50 uL of p-dime-thylaminobenzaldehyde (DMAB) dissolved in HC1 (1.3 g DMAB in 10 mL of 20% HC1). ' The derivatized samples were ready for HPLC analysis. Derivatized urea in standards and biological samples was analyzed using a Nova-Pak C18 column (4 &mum, 300 * 3.9 mm, Waters, USA). A ternary gradient elution program and UV detection at 255 and 414 nm were applied for urea analyses. Clear separation of urea from endogenous species present in biological materials was achieved in less than 20 min. Elution of derivatized urea was confirmed by an unsymmetrical chromatographic peak at 9.67 š0.11 min, which was a combination of two poorly resolved urea peaks eluted at 8.54 š 0.07 and 9.84 š 0.08 min. ; -' Average recoveries of urea standards added to the assayed biological materials were satisfactory, especially when detection at 414 nm (101.2%) was applied. Precision of the method with detection at 255 nm was inferior (CV 2.65%) to that performed at 414 nm (CV 1.98%). The proposed method with UV monitoring at 255 and 414 nm offers low detection limits (5.62 and 43 ng, respectively) and quantification limits (18.7 and 142 ng, respectively). It provides satisfactory accuracy, precision, and sensitivity of determination of urea. Liquid chromatography with UV monitoring at 255 nm revealed that the presence of endogenous substances in the assayed biological materials affect accurate and precise integration of the

PL

Opisano metodę HPLC pozwalającą na proste i szybkie oznaczanie mocznika w płynach fizjologicznych pozyskiwanych od zwierząt gospodarskich. W metodzie tej do detekcji wykorzystano detektor z matrycą diodową. Do płynów fizjologicznych (osocze krwi, mocz i mleko) dodawano 20%kwas trichlorooctowy; następnie uzyskanąmieszaninę wirowano. Do 200 μL supernatantu dodawano 50 &muL p-dimetyloaminobenzaldehydu (DMAB) w HC1 (l .3 g DMAB w l0 mL 20%HC1). Pochodna mocznika w badanych próbkach była gotowa do analizy. Pochodną mocznika analizowano przy użyciu kolumny Nova Pak Cl18 (4 μm, 300 x 3.9 mm, Waters). Zastosowano elucję gradientową! wykrywanie przy długości fali 255 i 414 nm. Zadowalające rozdzielenie mocznika od endogennych składników próbek uzyskano w czasie krótszym niż 20 min. Pochodna mocznika, jako niesymetryczny pik, pojawiła się w 9,67 š0,11 min; pik ten był kombinacją dwóch pików pojawiających się w 8,54 š 0,07 oraz 9,84 š 0,08 min. Średni odzysk wzorców mocznika dodanych do badanych próbek był zadowalający (101,2%), szczególnie przy detekcji UV przy długości fali 414 nm. Precyzja oznaczania mocznika przy długości fali 255 nm jest gorsza (CV = 2,65%) od precyzji oznaczania przy długości fali 414 nm (CV = 1,98%). Przy długości fali 255 i 414 nm otrzymano wykrywalność i oznaczalność wynoszące odpowiednio 5.62 oraz 43 ng oraz 18,7 i 142 ng. Opracowana metoda pozwala na oznaczenie mocznika z zadowalającą dokładnością, precyzjąoraz czułością. Chromatografia cieczowa z detekcjąprzy długości fali 255 nm ujawnia obecność endogennych substancji, które utrudniaj ą dokładne i precyzyjne oznaczanie mocznika w badanych próbkach biologicznych. Opracowana metoda z detekcją przy długości fali 414 nm analitycznąpozwalającąna proste i szybkie oznaczanie mocznika w płynach fizjologicznych oraz wybranych paszach.

18

Determination of fluoxetine in blood samples by high-performance liquid chromatography using derivatization reagent

Woźniakiewicz M., Kuczara J., Kościelniak P.

Chemia Analityczna

|

2009

|

Vol. 54, No. 4

667-677

EN

A rapid and selective chromatographic method for determination of fluoxetine in blood samples has been developed. The method is based on a selective reaction between 7,7,8,8-tetracyanoquinodimethane (TCNQ) and molecules with a secondary amine moiety, resulting in a purple solution. Blood samples were spiked with fluoxetine and nortriptyline as an internal standard; then, both compounds were extracted applying a microwave--assisted extraction - a novel technique for isolation of an analyte from biological matrix. After extraction, dried residues were dissolved in acetonitrilic solution of TCNQ and heated for 30 minutes at 80°C. The obtained intense purple-blue colored solutions were then analyzed by high performance liquid chromatography with diode-array detection. Chromato-grams were recorded at 567 nm. Limits of detection and quantification of fluoxetine in blood were 0.03 and 0.10 μgmL-1, respectively. It was concluded therefore that fluoxetine can be determined in blood in the therapeutic concentration range. The developed method has been applied to the analysis of whole blood samples collected from a female patient treated with Seronil® 20 (20 mg of fluoxetine).

PL

Opracowano szybką i selektywną chromatograficzną metodę oznaczania fluoksetyny w próbkach krwi. Podstawą metody jest selektywna reakcja miedzy 7,7,8,8-tetracyjano-chinodimetanem (TCNQ), a związkami zawierającymi drugorzędowe aminy, w wyniku której otrzymywany jest roztwór barwy fioletowej. Do próbek krwi dodawano fluoksetynę oraz nortryptylinę jako standard wewnętrzny, a następnie oba związki wyosabniano na drodze ekstrakcji ciecz-ciecz wspomaganej promieniowaniem mikrofalowym-nowoczesnej techniki izolowania analitu z materiału biologicznego. Suchą pozostałość rekonstytuowano w acetonitrylowym roztworze TCNQ, po czym ogrzewano w 80°C przez 30 min. Otrzymane roztwory barwy fioletowej analizowano za pomocą wysokosprawnej chromatografii cieczowej z detekcją spektrofotometryczną DAD. Chromatogramy rejestrowano przy długości fali 567 nm. Granice wykrywalności i oznaczalności fluoksetyny we krwi wynosiły odpowiednio 0,03 i O, l O μ g mL-1, co pozwala na oznaczenie fluoksetyny we krwi w stężeniach terapeutycznych. Opracowaną metodę zastosowano do analizy próbki krwi pełnej pochodzącej od pacjentki leczonej Seronilem® 20 (o zawartości 20 mg fluoksetyny).

19

Analysis of major urinary aminothiols by high-performance liquid chromatography with ultraviolet detection

Kuśmierek K, Bald E.

Acta Chromatographica

|

2009

|

Vol. 21, no. 3

411--420

EN

High-performance liquid chromatography has been used for measurement of the concentrations of total cysteine and cysteinylglycine in human urine. The method involved conversion of disulfides to their reduced counterparts by use of tris(2-carboxyethyl)phosphine hydrochloride, derivatization with 1-benzyl-2-chloropyridinium bromide, and ion-pairing reversed-phase high-performance liquid chromatographic separation with ultraviolet detection at 315 nm. The linearity of the method was validated in the ranges 50–300 and 5–50 µmol L -1 urine for cysteine and cysteinylglycine, respectively; regression coefficients were better than 0.999. The detection and quantitation limits were 0.2 and 0.5 µmol L -1, respectively, for both analytes. Intra-assay and inter-assay imprecision were below 6.0%, and accuracy was 98.95–100.80%. The method was applied to urine samples donated by apparently healthy volunteers.

20

HS-SPME-CGC-PID determination of aldehydes in rectified spirits and vodkas after derivatisation with 2,4,6-trichlorophenylhydrazine (TCPH)

Curyło J., Wardencki W.

Chemia Analityczna

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2005

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Vol. 50, No. 4

735-748

EN

A novel method for the determination of aldehydes in spirits and unfavoured alcoholic beverages using 2,4,6-trichlorophenylhydrazine (TCPH) derivatising agent has been developed. The proposed approach is at least 100-fold less expensive than the headspace solid phase microextraction (HS-SPME) and gas chromatography (GC) involving another derivatising reagent - frequently recommended o-2,374,5.6- pentafluorobenzylohydroxylo-amine (PFBHA). Conditions of derivatisation, extraction and final chromatographic analysis have been determined. The application of photoionisation detector (PID), instead of the commonly used electron capture detector (BCD), allowed one to obtain simple chromato-grams of the formed hydrazones. For the most of investigated aldehydes limits of detection (LODs) were in the range 0.002-0.070 mg dm-3. Relative standard deviations (RSDs) did not exceed 10% (except for formaldehyde and acrolein). The total analysis time was ca 1.5 h.

PL

W pracy przedstawiono nową metodę oznaczania aldehydów w spirytusach i wyrobach spirytusowych czystych z zastosowaniem 2,4,6-trichlorofenylohydrazyny (TCPH) jako odczynnika dery watyzującego. Zaproponowana metoda jest co najmniej 100-krotnie tańsza od mikroekstrakcji do fazy stacjonarnej z fazy nadpowierzchniowej (HS-SPME) i chromatografii gazowej z zastosowaniem często zalecanej o-2,3.4,5.6-pentafluorobenzylohydroxy-loaminy (PFBHA). W pracy eksperymentalnie zoptymalizowano warunki derywatyzacji, ekstrakcji i końcowej analizy chromatograficznej. Dzięki zastosowaniu detektora fotojoni-zacyjnego (PID) uzyskano czytelne chromało gramy hydrazonów-pochodnych związków karbonylowych. W przypadku większości aldehydów granica wykrywalności znajdowała się w przedziale stężeń 0.002-0.070 mg dmsup-3. Względne odchylenie standardowe nie przekraczało 10% (z wyjątkiem formaldehydu i akroleiny). Całkowity czas analizy wynosił ok. 1.5 h.