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Derivatization Reagent (derivatization + reagent)
Kinds of Derivatization Reagent Selected AbstractsRapid capillary electrophoresis time-of-flight mass spectrometry separations of peptides and proteins using a monoquaternarized piperazine compound (M7C4I) for capillary coatingsELECTROPHORESIS, Issue 8 2008Anisa Elhamili Abstract A monoquaternarized piperazine, 1-(4-iodobutyl) 4-aza-1-azoniabicyclo[2,2,2] octane iodide (M7C4I), has been evaluated as a surface derivatization reagent for CE in combination with TOF MS for the analysis of proteins, peptides, and protein digests. The M7C4I piperazine, at alkaline pH, forms a covalent bond via alkylation of the ionized silanols producing a cationic surface with a highly stable and reversed EOF. The obtained surface yields rapid separations (less than 5,min) of peptides and proteins at acidic pH with high separation efficiencies (up to 1.1×106 plates/m for peptides and up to 1.8×106 plates/m for proteins) and no observed bleeding of the coating reagent into the mass spectrometer. The simplicity of the coating procedure also enables fast (2,min) regeneration of the surface, if necessary. This is useful in the analysis of complex samples in order to prevent possible memory effects. The potential of using M7C4I-coated capillaries for MS analysis of complex samples is demonstrated by the separation of peptides, proteins, and protein digests. Even more, the spectacular thing in which large intact proteins with molecular masses over 0.5,MDa could be separated. The coating showed good ability to handle these large proteins with high efficiency and retained peak shape as demonstrated by separation of IgG1 (150,kDa) and thyroglobulin (669,kDa). [source] Analysis of sub-ppb levels of Fe(II), Co(II), and Ni(II) by electrokinetic supercharging preconcentration, CZE separation, and in-capillary derivatizationELECTROPHORESIS, Issue 20 2007Marek Urbanek Abstract The analysis of sub-ppb levels of Fe(II), Co(II), and Ni(II) in heat exchanger fluids of nuclear power plants is needed to monitor corrosion. A method involving preconcentration with electrokinetic supercharging (electrokinetic injection with transient ITP), CZE separation, and in-capillary derivatization with ortho -phenanthroline (o -Phe) for direct UV detection was thus developed. First, a multizone BGE was loaded into the capillary by successive hydrodynamic introduction of zones of (i) o -Phe-containing BGE, (ii) BGE for the zonal separation, and (iii) ammonium-based leading electrolyte. Metal cations were electrokinetically injected and stacked at the capillary inlet behind this last leading zone. Finally, a terminating electrolyte zone was hydrodynamically introduced. When a constant voltage was applied, metal ions kept on concentrating isotachophoretically, then separated in CZE mode, were complexed by migrating through an o -Phe zone, and finally detected by direct absorbance. To detect extremely thin peaks, it was attempted for the first time to focus the derivatization reagent by inducing a second transient ITP, before labeling analytes, already separated in CZE mode. With this arrangement, LODs were about 30,ppt in pure water. In heat exchanger fluid matrices containing 1000,ppm bore and 2,ppm lithium, only Fe(II) cation was detected among the three cations of interest at the 1,ppb level using the present method, and its LOD was about ten times higher, due to the lower loading rate during electrokinetic injection. [source] Determination of thiol compounds by automated headspace solid-phase microextraction with in-fiber derivatizationFLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2006Qing Wang Abstract In this article, headspace solid-phase microextraction (HS-SPME) analysis of thiol compounds with both solid and aqueous samples was investigated using N -phenylmaleimide as an in-fiber derivatization reagent. The derivatives were analyzed using GC-MS. The HS-SPME method was executed on an automatic sampler and optimized by studying a variety of factors such as the selection of the fiber, extraction time, temperature, agitation speed, etc. Method validation was carried out by spiking known amounts of thiol compounds into the sample and calculating the concentration by standard addition. The relative standard deviations (RSD) for the majority of the thiols were less than 10%. The developed method resulted in a limit of detection (LOD) in the low microgram per liter for most of the thiols analyzed, which was about one order of magnitude lower than the HS-SPME without derivatization. Finally, the overall method was successfully applied for the determination of thiols in yellow onion, green onion and garlic. Copyright © 2006 John Wiley & Sons, Ltd. [source] Synthesis of 4-(7-diethylaminocoumarin-3-yl)benzeneisocyanate (DACB-NCO): A highly sensitive fluorescent derivatization reagent for alcohols in high-performance liquid chromatography,JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 2 2001Haruko Takechi 4-(7-Diethylaminocoumarin-3-yl)benzeneisocyanate (DACB-NCO) was synthesized as a new fluorescent derivatization reagent for alcohols for use in high-performance liquid chromatography (hplc). Saturated alcohols (C6 -C22) were derivatized in good yields into the corresponding fluorescent DACB-carbamic esters by treating with DACB-NCO. The DACB-carbamic esters of these alcohols were clearly separated on a reversed-phase hplc column (Inertsil ODS-2, mobile phase: methanol-water, excitation wavelength 402 nm; emission wavelength 488 nm). The detection limit (S/N = 3) of cetyl alcohol, as a test compound, was 5 fmol/10 ,l. [source] GC separation of amino acid enantiomers via derivatization with heptafluorobutyl chloroformate and Chirasil- L -Val columnJOURNAL OF SEPARATION SCIENCE, JSS, Issue 22 2009Helena Zahradní Abstract Heptafluorobutyl chloroformate (HFBCF), a recently introduced derivatization reagent, was examined in enantioseparation of amino acids (AAs) by GC. Twenty proteinogenic AAs, plus ornithine, cystine and 4-fluorophenylalanine (internal standard) were treated with the reagent and separation properties of the derivatives were assessed on a Chirasil-Val capillary column. Nineteen AA enantiomers were efficiently separated in 43,min except proline, arginine and cystine. The HFBCF derivatives of the studied DL -AAs show improved separation over other chloroformate-based derivatives hitherto reported. A combination of the improved and faster separation with a simple derivatization protocol, involving an immediate one-step reaction,extraction in two-phase aqueous-organic medium, and low elution temperatures extend application of HFBCF to chiral AA analysis. [source] Detection of carbonyl groups in triterpenoids by hydroxylamine hydrochloride derivatization using electrospray ionization mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 12 2008Xin Liu A rapid, simple electrospray ionization mass spectrometry (ESI-MS) sensitivity enhancement method for detecting carbonyl groups in triterpenoids has been developed by using hydroxylamine hydrochloride (NH2OH,·,HCl) as a derivatization reagent. We use the oxime formed during the derivatization reactions and its Beckmann rearrangement intermediates as a means of detecting the carbonyl groups originally present in these triterpenoids. In comparison with other derivatization methods reported in the literature, this method is simple, specific and can be used to detect carbonyl groups in triterpenoids which have low polarity and are poorly or non-ionizable. Moreover, it can also be used to detect hydroxyl groups by using the Dess-Martin periodinane (DMP) to convert primary and secondary hydroxyls into carbonyl groups. Copyright © 2008 John Wiley & Sons, Ltd. [source] Development of a fluorimetric detection method for cinnabarinic acid using ortho -tolyl hydrazine as the derivatization reagentBIOMEDICAL CHROMATOGRAPHY, Issue 3 2010Hideaki Iizuka Abstract A fluorimetric detection method for one of the tryptophan metabolites, cinnabarinic acid (CA), which has recently been reported to have the ability to induce apoptosis in thymocytes, was developed using o -tolyl hydrazine (TH) as the derivatization reagent. The carbonyl group at position 3 in CA was tagged with the hydrazino moiety of TH at 100°C for 30 min, and the generated derivative, CA tagged with TH, fluoresced at 412 nm with a 316 nm excitation wavelength. The CA tagged with TH was separated on a reversed-phase HPLC and detected fluorometrically. The relative standard deviation was in the range of 1.1,8.9% (n = 3), and the detection limit was approximately 12?fmol (signal-to-noise ratio, 3). The proposed HPLC method can be useful for the sensitive detection of CA. Copyright © 2009 John Wiley & Son, Ltd. [source] Novel 6-hydroxy chroman-based derivatization reagent for HPLC-EC: challenges of ,unsuspected' chiralityBIOMEDICAL CHROMATOGRAPHY, Issue 6 2009Nuggehally R. Srinivas No abstract is available for this article. [source] Development of a simultaneous liquid,liquid extraction and chiral derivatization method for stereospecific GC-MS analysis of amphetamine-type stimulants in human urine using fractional factorial designBIOMEDICAL CHROMATOGRAPHY, Issue 9 2008W. R. Wan Aasim Abstract A stereospecific gas chromatography,mass spectrometry analysis method for amphetamine-type stimulants in human urine was recently developed. For maximum efficiency, liquid,liquid extraction and chiral derivatization of the analytes using (R)-(,)- , -methoxy- , -(trifluoromethyl)phenylacetyl chloride were performed simultaneously. The effects of (1) use of saturated sodium chloride in 2.0 m sodium hydroxide, (2) extraction solvent volume, (3) percentage of triethylamine, (4) derivatization reagent volume, (5) sample mixing time, (6) incubation temperature and (7) incubation time on method sensitivity and variability were assessed using a two-level, eight-run Plackett,Burman design followed by a fold-over design. The use of saturated sodium chloride solution and the derivatization reagent volume were significant factors (ANOVA, p < 0.01). The saturated sodium chloride solution decreased sensitivity whereas an increased volume of derivatization reagent increased sensitivity. Calibration curves for all analytes were linear between 5 and 500 µg/L, with correlation coefficients of >0.99. Detection limits were ,2.3 µg/L and quantitation limits ,7.7 µg/L. Reproducibility was good, with relative standard deviation values at <20%. Recovery exceeded 100% for most analytes. The experimental design enabled easy and rapid identification of significant factors using a minimal number of samples. This method has good potential for studies requiring rapid and sensitive stereospecific quantification of amphetamine-type stimulants. Copyright © 2008 John Wiley & Sons, Ltd. [source] Simultaneous liquid chromatographic assay of amantadine and its four related compounds in phosphate-buffered saline using 4-fluoro-7-nitro-2,1,3-benzoxadiazole as a fluorescent derivatization reagentBIOMEDICAL CHROMATOGRAPHY, Issue 5 2006Yasuhiko Higashi Abstract Simultaneous HPLC assay of 1-adamantanamine hydrochloride (amantadine) and its four related compounds [2-adamantanamine hydrochloride (2-ADA), 1-adamantanmethylamine (ADAMA), 1-(1-adamantyl)ethylamine hydrochloride (rimantadine) and 3,5-dimethyl-1-adamantanamine hydrochloride (memantine)] in phosphate-buffered saline (pH 7.4) after pre-column derivatization with 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) was developed. Phosphate-buffered saline samples were mixed with borate buffer and NBD-F solution in acetonitrile at 60°C for 5 min and injected into HPLC. Five derivatives were well separated from each other. The lower limits of detection of amantadine, 2-ADA, ADAMA, rimantadine and memantine were 0.008, 0.001, 0.0008, 0.0015 and 0.01 µg/mL, respectively. The coefficients of variation for intra- and inter-day assay were less than 6.4 and 8.2%, respectively. The method presented was applied to a binding study of these compounds to human ,1 -acid glycoprotein. While affinity constants and capacities for ADAMA, rimantadine and memantine were calculated by means of Scatchard plots, those for the others were not determined. ADAMA, rimantadine and memantine were bound with different affinities and capacities. These results indicate that NBD-F is a good candidate as a fluorescent reagent to simultaneously determine amantadine and its four related compounds by HPLC after pre-column derivatization. Our method can be applied to binding studies for protein. Copyright © 2005 John Wiley & Sons, Ltd. [source] A fully automated amino acid analyzer using NBD-F as a ,uorescent derivatization reagentBIOMEDICAL CHROMATOGRAPHY, Issue 9 2004Chiaki Aoyama Abstract A fully automated amino acid analyzer using NBD-F (4-,uoro-7-nitro-2,1,3-benzoxadiazole) as a ,uorescent derivatization reagent was developed. The whole analytical process was fully automated from derivatization, injection to HPLC separation and quantitation. The derivatization reaction conditions were re-evaluated and optimized. Amino acids were derivatized by NBD-F for 40 min at room temperature in the borate buffer (pH 9.5). The derivatives were separated within 100 min and ,uorometrically detected at 540 nm with excitation at 470 nm. The detection limits for amino acids were in the range of 2.8,20 fmol. The calibration curves were linear over the range of 20 fmol to 20 pmol on column with the correlation coef,cients of 0.999. The coef,cients of variation were less than 5% at 3 pmol injection for all amino acids. Amino acids in rat plasma were determined by the proposed HPLC method. Copyright © 2004 John Wiley & Sons, Ltd. [source] HPLC purification and re-evaluation of chemical identity of two circular bacteriocins, gassericin A and reutericin 6LETTERS IN APPLIED MICROBIOLOGY, Issue 4 2010K. Arakawa Abstract Aim:, The study aimed for the complete purification and recharacterization of the highly hydrophobic circular bacteriocins, gassericin A and reutericin 6. Methods and Results:, Gassericin A and reutericin 6 were purified to homogeneity using previously described method and reverse-phase HPLC with an octyl column and eluents of aqueous acetonitrile and 2-propanol. Mass analysis, N-terminal sequencing and bacteriocin assay of the HPLC-purified bacteriocins showed the two bacteriocins had identical seamless circular structures with the same m/z value (5651) of [M + H]+ and both had the same specific activity. d/l- amino acid composition analysis using two distinct methods with the chiral fluorescent derivatization reagents (+)-1-(9-fluorenyl)ethyl chloroformate and o -phthalaldehyde/N -acetyl- l -cystein revealed neither gassericin A nor reutericin 6 contained d -alanine residues contrary to our previous results. Conclusion:, Purified gassericin A and reutericin 6 are chemically identical circular molecules containing no d -alanine residues. Significance and Impact of the Study:, The HPLC conditions developed in this study will facilitate advanced purification and correct characterization of other highly hydrophobic bacteriocins. [source] Synthesis of benzofurazan derivatization reagents for short chain carboxylic acids in liquid chromatography/electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS)BIOMEDICAL CHROMATOGRAPHY, Issue 4 2009Tomofumi Santa Abstract Benzofurazan derivatization reagents, 4-[2-(N,N -dimethylamino)ethylaminosulfonyl]-7-(2-aminopentylamino)-2,1,3-benzoxadiazole (DAABD-AP) and 4-[2-(N,N -dimethylamino) ethylaminosulfonyl]-7-(2-aminobutylamino)-2,1,3-benzoxadiazole (DAABD-AB), for short-chain carboxylic acids in liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) were synthesized. These reagents reacted with short chain carboxylic acids in the presence of the condensation reagents at 60°C for 60 min. The generated derivatives were separated on the reversed-phase column and detected by ESI-MS/MS with the detection limits of 0.1,0.12 pmol on column. Upon collision-induced dissociation, a single and intense product ion at m/z 151 was observed. These results indicated that DAABD-AP and DAABD-AB are suitable as the derivatization reagents in LC/ESI-MS/MS analysis. Copyright © 2008 John Wiley & Sons, Ltd. [source] New thinking in the development of novel derivatization reagents for liquid chromatography,mass spectrometric detectionBIOMEDICAL CHROMATOGRAPHY, Issue 1 2009Nuggehally R Srinivas No abstract is available for this article. [source] Recent progress in the development of derivatization reagents having a benzofurazan structureBIOMEDICAL CHROMATOGRAPHY, Issue 4 2008Tomofumi Santa Abstract Chemical derivatization is often used to enhance the detectability of the target compounds and to improve the separation efficiency in high-performance liquid chromatography (HPLC). In this review, we describe the recent progress in the development of derivatization reagents having a benzofurazan structure, namely, the fluorogenic reagents, water-soluble reagents, reagents for the analysis of peptides and proteins, and reagents for mass spectrometric detection. The application of these reagents to bio-samples is also briefly described. Copyright © 2007 John Wiley & Sons, Ltd. [source] Synthesis of benzofurazan derivatization reagents for carboxylic acids in liquid chromatography/electrospray ionization,tandem mass spectrometryBIOMEDICAL CHROMATOGRAPHY, Issue 11 2007Tomofumi Santa Abstract The applicability of benzofurazan derivatization regents to carboxylic acids analysis in LC/ESI-MS/MS (high-performance liquid chromatography/electrospray ionization tandem mass spectrometry) was examined. The product ion spectra of DAABD-AE {4-[2-(N,N -dimethylamino)ethylaminosulfonyl]-7-(2-aminoethylamino)-2,1,3-benzoxadiazole}, DAABD-PZ {4-[2-(N,N -dimethylamino)ethylaminosulfonyl]-7- N -piperazino-2,1,3-benzoxadiazole}, DAABD-PiCZ {4-[4-carbazoylpiperidin-1-yl]-7-[2-(N,N -dimethylamino)ethylaminosulfonyl]-2,1,3-benzoxadiazole}, DAABD-ProCZ {4-[2-carbazoylpyrrolidin-1-yl]-7-[2-(N,N -dimethylamino) ethylaminosulfonyl]-2,1,3-benzoxadiazole} and DAABD-Apy {4-[2-(N,N -dimethylamino)ethylaminosulfonyl]-7-(3-aminopyrrolidin-1-yl)-2,1,3-benzoxadiazole}, and their acetylated compounds were obtained. An intense fragment ion at m/z 151 corresponding to (dimethylamino)ethylaminosulfonyl moiety was observed in each spectra, suggesting that these reagents were suitable for ESI-MS/MS analysis. DAABD-AE, DAABD-APy and DAABD-PZ were applied to the analysis of octanoic acid and it was found that DAABD-AE and DAABD-APy gave high signal intensity suitable for LC/ESI-MS/MS. Copyright © 2007 John Wiley & Sons, Ltd. [source] Synthesis of benzofurazan derivatization reagents for carboxylic acids and its application to analysis of fatty acids in rat plasma by high-performance liquid chromatography,electrospray ionization mass spectrometryBIOMEDICAL CHROMATOGRAPHY, Issue 10 2005Yuhki Tsukamoto Abstract The derivatization regents for carboxylic acids, DAABD-AE {4-[2-(N,N -dimethylamino)ethylaminosulfonyl]7-(2-aminoethylamino)-2,1,3-benzoxadiazole}, MePZBD-AE {[4-(4- N -methyl)piperazinosulfonyl]-7-(2-aminoethylamino)-2,1,3-benzoxadiazole} and APZBD-NHMe {[4-(4- N -aminoethyl)piperazinosulfonyl]-7-methylamino-2,1,3-benzoxadiazole} were developed for electrospray ionization,mass spectrometry (ESI-MS). The derivatization reaction with fatty acids was completed at 60°C within 30 min. The derivatives of fatty acids were separated on a reversed-phase column and detected with ESI-MS. The detection limits attained for fatty acids were femtomol range and the calibration curves were linear over the range from 0.1 to 100 pmol (r2 > 0.992) for DAABD-AE and MePZBD-AE. DAABD-NHMe was applied to the analysis of fatty acids in rat plasma samples. Copyright © 2005 John Wiley & Sons, Ltd. [source] Chemiluminescence detection in HPLC and CE for pharmaceutical and biomedical analysisBIOMEDICAL CHROMATOGRAPHY, Issue 2-3 2003Famei Li Abstract The present paper reviews the developments and applications of chemiluminescence detection with HPLC and CE in pharmaceutical and biomedical analysis. The chemiluminescence systems, chemiluminogenic reagents and derivatization reagents, improvements in instrumental design as well as their contributions to the practical applications, are all presented. The advantages and limitations of current detection methodology and future prospects for improvement are briefly discussed. Copyright © 2003 John Wiley & Sons, Ltd. [source] | |||||||||||||