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1.
Food Chem ; 399: 133918, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35994858

RESUMO

A core-shell magnetic sulfonatocalix[6]arene covalently cross-linked polymer was proposed as a magnetic adsorbent, combined with ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) for the enrichment and determination of epoxy derivatives in canned foods. The adsorbent has high density of host-guest recognition functional groups, abundant binding sites and suitable cavity size, showing good extraction performance for epoxy derivatives. Quantum chemical simulation calculations provedmultiple interaction forces in the adsorption process. Theextractionparameterswere investigated. Under optimized experimental conditions, 13 kinds of target analytes showed low detection limits (0.0072-0.023 ng/g) and good precisions (RSDs of 0.8 %-9.4 %). This method has been successfully applied to the simultaneous determination of 13 kinds of epoxy derivatives in different food samples including canned beverage, fish, meat, and milk powder. Satisfactory recoveries (74.9 %-118 %) were obtained. The results showed the potential application prospects in the enrichment and detection of hazardous substances in food.


Assuntos
Éter , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão/métodos , Alimentos em Conserva/análise , Glicerol , Éteres de Glicerila , Indicadores e Reagentes , Fenômenos Magnéticos , Polímeros/análise , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
2.
J. Health Biol. Sci. (Online) ; 10(1): 1-8, 01/jan./2022. tab, graf, ilus
Artigo em Português | LILACS | ID: biblio-1378478

RESUMO

Objetivos: descrever os aspectos epidemiológicos, espaciais e temporais da leishmaniose visceral humana, no município de Sobral, no período de 2007 a 2019. Métodos: foi realizado um estudo epidemiológico descritivo e ecológico de análise espacial e temporal, com uso dos programas Quantum-Gis e Joinpoint. Resultados: foram confirmados 316 casos novos, predominantemente, no sexo masculino, nas faixas etárias de 1 a 4 anos (26,3%) e de 20 a 39 anos (24,0%), na zona urbana. Febre (95,9%), fraqueza (85,1%), emagrecimento (80,1%), palidez (73,7%), esplenomegalia (75,6%) e hepatomegalia (69,3%) foram os sinais clínicos mais frequentes. A doença se concentrou em quatro bairros: Terrenos Novos, Centro, Expectativa e Sinhá Saboia, expressando áreas mais densas (quentes). A incidência e a letalidade foram crescentes no início do período e decrescentes no final, com uma inversão destes indicadores no ano de 2014. Conclusão: em Sobral, a leishmaniose visceral humana é um agravo considerado relevante para o serviço de vigilância em saúde com necessidade de intensificação das ações de controle entomológico, zoonótico e de manejo ambiental, principalmente nas áreas mais densas.


Objectives: the objective was to describe the epidemiological, spatial, and temporal aspects of human visceral leishmaniasis, in the municipality of Sobral, from 2007 to 2019. Methods: A descriptive, spatial and temporal ecological study was carried out using Quantum-Gis and Joinpoint programs. Results: 316 new cases were confirmed, predominantly in males, in the age groups of 1 to 4 years (26.3%) and 20 to 39 years (24.0%), mainly in the urban area. Fever (95.9%), weakness (85.1%), weight loss (80.1%), pallor (73.7%), splenomegaly (75.6%), and hepatomegaly (69.3%) were the most frequent clinical signs. The disease was concentrated in four neighborhoods (Terrenos Novos, Centro, Expectativa, and Sinhá Saboia), hot spots. The incidence and case-fatality increased at the beginning of the period but decreased at the end, with an inversion in these in the year 2014. Conclusion: In Sobral, human visceral leishmaniasis is a disease considered relevant to the health surveillance service, with the need to intensify entomological, zoonotic, and environmental management actions, especially in denser areas.


Assuntos
Leishmaniose Visceral , Sinais e Sintomas , Vigilância Sanitária , Epidemiologia , Mortalidade , Indicadores e Reagentes , Grupos Etários
3.
Chem Pharm Bull (Tokyo) ; 70(9): 650-661, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36047236

RESUMO

The acetamide moiety is a general functional group present in many natural and pharmaceutical products. Herein, we report two new reagents, p-methoxybenzyl N-acetylcarbamate potassium salt (PM-BENAC-K) and 2,4-dimethoxybenzyl N-acetylcarbamate potassium salt (2,4-DM-BENAC-K), which are refined versions of the benzyl N-acetylcarbamate potassium salt (BENAC-K). These compounds, which we reported as simple equivalents of N-acetamide nucleophiles, are stable and easy-to-handle powders that react with a variety of alkyl halides and sulfonates to afford substituted products in good yields. The products were transformed into N-alkylacetamides after p-methoxybenzyloxycarbonyl (Moz) or 2,4-dimethoxybenzyloxycarbonyl (Dmoz) cleavage under mild acidic conditions. The acetyl groups in the substituted products of PM- and 2,4-DM-BENAC-Ks were removed using K2CO3 in methanol to afford Moz- and Dmoz-protected amines, respectively. Hence, the new BENAC-Ks acted as versatile equivalents of both N-acetamide and Moz/Dmoz-protected nitrogen nucleophiles and can be used in synthetic studies of natural and pharmaceutical products.


Assuntos
Carbamatos , Sais , Acetamidas , Indicadores e Reagentes , Estrutura Molecular , Preparações Farmacêuticas , Potássio
4.
Org Lett ; 24(36): 6686-6691, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36053069

RESUMO

The synthesis of aniline derivatives, common building blocks in many pharmaceuticals, agrochemicals, dyes or polymers, has been limited to reactions based on benzene-toluene-xylene derivatives (BTX) due to their ample availability. Despite the large number of existing methodologies, the synthesis of chiral 4-(sec-alkyl)anilines has not been accomplished so far. In this work, a tandem strategy based on the generation of a reactive aza-p-quinone methide (aza-p-QM) intermediate followed by Cu(I)-catalyzed addition of Grignard reagents has been developed.


Assuntos
Benzeno , Xilenos , Agroquímicos , Compostos de Anilina , Catálise , Corantes , Indicadores e Reagentes , Indolquinonas , Preparações Farmacêuticas , Polímeros , Tolueno
5.
J Chromatogr A ; 1681: 463492, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36116368

RESUMO

Previous studies on stationary phase gradients have inspired a new phase of theoretical work and an expansion of the concept to include multiple retention mechanisms. The theoretical work presented here corroborates previous reports that a stationary phase gradient can produce selectivity in a separation as effectively as careful adjustments to a mobile phase gradient program, especially when such column is operated in mobile phase gradient elution mode. In reality, no column is singularly based on one type of interaction mechanism, and many columns are nowadays designed to solicit multiple solute to stationary phase interactions. These mixed-mode columns inspired us to give more careful consideration to the idea of dual stationary phase gradients. With the theory applied here, it is suggested that the modulation of two unique interaction mechanisms across a chromatographic column has the potential to open up previously unseen selectivities. With the increasing prevalence of mixed-mode columns, we believe there will be ample opportunity to explore these new concepts in experimental work.


Assuntos
Cromatografia Líquida , Cromatografia Líquida/métodos , Indicadores e Reagentes
6.
Org Lett ; 24(36): 6510-6514, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36052998

RESUMO

Aromatic halides constitute a valuable class of building blocks that are commonly used in organic synthesis. In this study, we demonstrate usage of aryl bromides and aryl iodides in C-Br or C-I bond formation. Methyl 2-bromobenzoate and 2-nitrophenyl iodides were developed as mild and effective bromination and iodination reagents for functionalization of arene-tethered diols. This efficient cascaded catalysis can be applied to the total syntheses of natural product Mafaicheenamine A and Claulamine A.


Assuntos
Produtos Biológicos , Halogenação , Brometos/química , Catálise , Indicadores e Reagentes , Iodetos/química
7.
J Org Chem ; 87(18): 12214-12224, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36053202

RESUMO

Practical copper-promoted N-alkylation and bromination of arylamines/indazoles with alkyl bromides are described; the N-alkylation-C-4-bromination and N-dialkylation-C-4-bromination of arylamines, and N-alkylation-C-3-bromination of indazoles, with alkyl bromides have been analyzed. The full use of alkyl bromides as alkylating and brominating building blocks without atom wastage, indicating excellent atom and step economy, has been highlighted. Eco-friendly oxygen and water are the reaction oxidant and byproduct, respectively.


Assuntos
Brometos , Cobre , Alquilação , Aminas , Halogenação , Indazóis , Indicadores e Reagentes , Oxidantes , Oxigênio , Água
8.
Anal Chem ; 94(37): 12595-12603, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36063091

RESUMO

An absolute quantitative analysis of free radicals by combining the effective magnetic moment method and the quantitative electron paramagnetic resonance [qEPR] method is proposed. This combined method utilizes the advantages of both the analytical methods and compensates for their disadvantages. In the effective magnetic moment method, the magnetic moment under a constant magnetic field is measured accurately using a superconducting quantum interference device. The qEPR method compares a "primary standard sample" and "secondary standard sample". The effective magnetic moment method was used to determine the purity of the primary standard sample. The qEPR method realizes a simple purity analysis of free-radical reagents with traceability to the International System of Units (SI). The purity of the free radicals by the qEPR method for pure 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl benzoate [4HTB], 1-oxyl-2,2,6,6-tetramethyl-4-hydroxypiperidine [TEMPOL], and di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium [DPPH] reagents was obtained with a relative expanded uncertainty of 0.7% for 4HTB to 1.5% for the DPPH. These small uncertainties were almost equal to those of the purity of the primary standard samples and were achieved by adopting in-plane positioning of the measured sample perpendicular to the cylindrical axis of the sample space of the superconducting quantum interference device. Some purity values of the free radicals for these reagents differed from those stated by the manufacturers. This combined method enables short-time quality control of pure radical reagents, instead of quality control by separation analytical methods or titrations.


Assuntos
Benzoatos , Fenômenos Magnéticos , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres , Indicadores e Reagentes
9.
Anal Chem ; 94(37): 12884-12889, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36069050

RESUMO

In this study, we present a fluidic dispensing system that can automate the sequential fluidic delivery of multiple reagents for lateral flow assays. Highly sensitive assays typically require multiple solution-based sequences, including washing steps and signal amplification. However, implementation of these types of sequences on an automated and highly sensitive point-of-care testing (POCT) platform remains challenging. Our platform consists of two disposable cartridges with reagent chambers and a test strip and an instrument that has a mechanical timer to actuate the cam-follower-gear components. The timer rotation sequentially shifts the position of the chambers and loads the reagents to the test paper strip. The dispensing intervals are controlled at a variation of <1% within a total actuation time of 60 min. Unlike other POCT devices, the timing of fluid delivery in our timer-actuated platform is not dependent on the selection of substrates and reagents, and the unique approach to fluidic delivery results in no reagent overlap or carryover, minimal reagent loss, and highly accurate fluidic timing control for highly sensitive solution-based assays. As a model application, the proposed platform applies a gold enhancement solution to amplify the detection signal and detect prostate-specific antigen with a limit of detection of 86 pg/mL within 27 min. This platform provides an opportunity for solution-based POCT applications with high sensitivity, thereby satisfying the requirement for user-friendly operations in resource-limited settings.


Assuntos
Testes Imunológicos , Antígeno Prostático Específico , Ouro , Humanos , Imunoensaio/métodos , Indicadores e Reagentes , Masculino , Testes Imediatos
10.
Int J Mol Sci ; 23(17)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36076941

RESUMO

Oligonucleotides have many important applications, including as primers in polymerase chain reactions and probes for DNA sequencing. They are proposed as a diagnostic and prognostic tool for various diseases and therapeutics in antisense therapy. Accordingly, it is necessary to develop liquid chromatography and solid phase extraction methods to separate oligonucleotides and isolate them from biological samples. Many reviews have been written about the determination of these compounds using the separation technique or sample preparation for their isolation. However, presumably, there are no articles that critically review the adsorbents used in liquid chromatography or solid phase extraction. The present publication reviews the literature from the last twenty years related to supports (silica, polymers, magnetic nanoparticles) and their modifications. The discussed issues concern reversed phase (alkyl, aromatic, cholesterol, mixed ligands), ion-exchange (strong and weak ones), polar (silica, polyhydroxy, amide, zwitterionic), and oligonucleotide-based adsorbents.


Assuntos
Oligonucleotídeos , Extração em Fase Sólida , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Indicadores e Reagentes , Oligonucleotídeos/química , Dióxido de Silício/química
11.
Phys Chem Chem Phys ; 24(35): 20901-20912, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36047252

RESUMO

Herein, a series of compact anthracene carboxyimide (ACI) based donor-acceptor dyads were prepared by substituting bulky aryl moieties with various electron-donating ability to study the triplet-excited state properties. The ISC mechanism and triplet yield of the dyads were successfully tuned via structural manipulation. Efficient ISC (ΦΔ ≈ 99%) and long-lived triplet state (τT ≈ 122 µs) was observed for the orthogonal anthracene-labeled ACI derivative compared to the Ph-ACI and NP-ACI dyads, which showed fast triplet state decay (τT ≈ 7.7 µs). Femtosecond transient absorption study demonstrated the ultrafast charge separation (CS) and efficient charge recombination (CR) in the orthogonal dyads and ISC occurring via spin-orbit charge transfer (SOCT) mechanism (AN-ACI: τCS = 355 fs, τCR = 2.41 ns; PY-ACI: τCS = 321 fs, τCR = 1.61 ns), while in Ph-ACI and NP-ACI dyads triplet populate following the normal ISC channel (nπ* → ππ* transition), no CS was observed. We found that the attachment of suitable aryl donor moiety (AN- or PY-) to the ACI core can ensure the insertion of the intermediate triplet state, resulting in a small energy gap among charge separated state (CSS) and triplet state, which leads to efficient ISC in these derivatives. The SOCT-ISC-based AN-ACI dyad was confirmed to be a potent photodynamic therapeutic reagent; an ultra-low IC50 value (0.27 nM) that was nearly 214 times lower than that of the commercial Rose Bengal photosensitizer (57.8 nM) was observed.


Assuntos
Elétrons , Fármacos Fotossensibilizantes , Antracenos , Indicadores e Reagentes , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia
12.
J Am Chem Soc ; 144(36): 16316-16324, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36047787

RESUMO

We report here an efficient and highly diastereoselective intermolecular anti-Markovnikov hydroamination of unactivated alkenes with aliphatic azides in the presence of silane. The system tolerates a wide range of azides and alkenes and operates with alkene as limiting reagent. Mechanistic studies suggest a radical chain pathway that involves aminium radical formation, radical addition to alkenes and HAT from silane to ß-aminium alkyl radical. The use of sterically bulky silane is proposed to contribute to the excellent diastereoselectivity for HAT. Computational analysis uncovers the reaction pathway of aliphatic azide activation with silyl radical for aminyl radical formation.


Assuntos
Alcenos , Azidas , Indicadores e Reagentes , Silanos
13.
Molecules ; 27(17)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36080169

RESUMO

Herein, we present the application of fluorinated carbohydrate-derived building blocks for α-hydroxy ß-fluoro/ß-trifluoromethyl and unsaturated phosphonates synthesis. Pudovik and Horner-Wadsworth-Emmons reactions were applied to achieve this goal. The proposed pathway of the key reactions is supported by the experimental results, as well as quantum chemical calculations. The structure of the products was established by spectroscopic (1D, 2D NMR) and spectrometric (MS) techniques. Based on our data received, we claim that the progress of the Pudovik and HWE reactions is significantly influenced by the acidic protons present in the molecules as assessed by pKa values of the reagent.


Assuntos
Organofosfonatos , Carboidratos , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Organofosfonatos/química , Estereoisomerismo
14.
Molecules ; 27(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36080474

RESUMO

Conventional Staudinger reductions of organic azides are sluggish with aryl or bulky aliphatic azides. In addition, Staudinger reduction usually requires a large excess of water to promote the decomposition of the aza-ylide intermediate into phosphine oxide and amine products. To overcome the challenges above, we designed a novel triaryl phosphine reagent 2c with an ortho-SO2NH2 substituent. Herein, we report that such phosphine reagents are able to mediate the Staudinger reduction of both aryl and alkyl azides in either anhydrous or wet solvents. Good to excellent yields were obtained in all cases (even at a diluted concentration of 0.01 M). The formation of B-TAP, a cyclic aza-ylide, instead of phosphine oxide, eliminates the requirement of water in the Staudinger reduction. In addition, computational studies disclose that the intramolecular protonation of the aza-ylide by the ortho-SO2NH2 group is kinetically favorable and responsible for the acceleration of Staudinger reduction of the aryl azides.


Assuntos
Aminas , Azidas , Indicadores e Reagentes , Óxidos , Água
15.
Molecules ; 27(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36080484

RESUMO

Fatty acids (FAs) play pleiotropic roles in living organisms, acting as signaling molecules and gene regulators. They are present in plants and foods and may affect human health by food ingestion. As a consequence, analytical methods for their determination in biological fluids, plants and foods have attracted high interest. Undoubtedly, mass spectrometry (MS) has become an indispensable technique for the analysis of FAs. Due to the inherent poor ionization efficiency of FAs, their chemical derivatization prior to analysis is often employed. Usually, the derivatization of the FA carboxyl group aims to charge reversal, allowing detection and quantification in positive ion mode, thus, resulting in an increase in sensitivity in determination. Another approach is the derivatization of the double bond of unsaturated FAs, which aims to identify the double bond location. The present review summarizes the various classes of reagents developed for FA derivatization and discusses their applications in the liquid chromatography-MS (LC-MS) analysis of FAs in various matrices, including plasma and feces. In addition, applications for the determination of eicosanoids and fatty acid esters of hydroxy fatty acids (FAHFAs) are discussed.


Assuntos
Ácidos Graxos , Espectrometria de Massas em Tandem , Cromatografia Líquida/métodos , Ácidos Graxos/análise , Ácidos Graxos Insaturados , Humanos , Indicadores e Reagentes , Espectrometria de Massas em Tandem/métodos
16.
J Nat Prod ; 85(8): 2122-2125, 2022 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-35976728

RESUMO

Echinosulfonic acid D, a sponge metabolite whose structure was recently reassigned, was synthesized for the first time. The key step is the double indolization of dimethylbarbituric acid using the umpolung indole reagent, followed by a hydrolysis/decarboxylation/esterification sequence.


Assuntos
Alcaloides Indólicos , Ácidos Sulfônicos , Hidrólise , Indicadores e Reagentes
17.
Chem Commun (Camb) ; 58(72): 9991-10003, 2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-35993918

RESUMO

Electrophilic aminating reagents have seen a renaissance in recent years as effective nitrogen sources for the synthesis of unprotected amino functionalities. Based on their reactivity, several noble and non-noble transition metal catalysed amination reactions have been developed. These include the aziridination and difunctionalisation of alkenes, the amination of arenes as well as the synthesis of aminated sulfur compounds. In particular, the use of hydroxylamine-derived (N-O) reagents, such as PONT (PivONH3OTf), has enabled the introduction of unprotected amino groups on various different feedstock compounds, such as alkenes, arenes and thiols. This strategy obviates undesired protecting-group manipulations and thus improves step efficiency and atom economy. Overall, this feature article gives a recent update on several reactions that have been unlocked by employing versatile hydroxylamine-derived aminating reagents, which facilitate the generation of unprotected primary, secondary and tertiary amino groups.


Assuntos
Aminas , Hidroxilaminas , Alcenos , Hidroxilamina , Indicadores e Reagentes , Estrutura Molecular
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 283: 121713, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35952592

RESUMO

Inorganic arsenic especially As(III) is considered a carcinogenic substance and its measurement is important in water samples. In this work, an inexpensive flow injection analysis system was designed for the photometric determination of As(III) at low concentrations. For this purpose, a light-emitting diode (LED) based photometer with a miniaturized detector, was fabricated and used as a determination apparatus and methyl orange was used as a detecting reagent. The fabricated photometer employed the LEDs, as a light source and the light detector. The λmax of emission for emitter and detector LEDs were 525 and 625 nm, respectively. Determination of As (III) was based on its inhibition effect on the redox reaction between methyl orange and X2 (Cl2 or Br2). The decolorization of the reaction products in the FIA system was monitored using the homemade flow cell detector. Analytical figures of merit including linear responses ranging from 0.03 to 3.0 mg/l of As(III) (r = 0.994), detection limits of 0.007 mg/l As(III), RSD% of 1.5% (n = 7), low reagent consumption per determination, and sampling throughput of 50 determinations per hour were achieved.


Assuntos
Análise de Injeção de Fluxo , Fotometria , Compostos Azo , Indicadores e Reagentes
19.
Anal Biochem ; 655: 114833, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35961398

RESUMO

This manuscript describes the formation of an artifact shoulder peak with a slightly larger retention time than the main peak under the standard non-reduced capillary electrophoresis with sodium dodecyl sulfate (nrCE-SDS) analysis of a therapeutic recombinant protein X, and clarifies the formation mechanism of the artifact caused by N-ethylmaleimide (NEM) during the sample preparation procedure. A design of experiment (DoE) approach was used to investigate the impact of the factors on the formation of the impurity. Additionally, orthogonal analytical experiments were performed to study the root cause of this phenomenon. The results consistently suggested that the Michael addition reaction between NEM and lysine residues in protein X, and decreased electrophoretic mobility due to increased molecular weight, was the root cause for the artifact, which could be partially inhibited by modifications of incubation conditions. Thus, before performing the nrCE-SDS method, the effects of alkylation reagents and sample preparation procedure on analytical results need to be considered seriously.


Assuntos
Artefatos , Eletroforese Capilar , Alquilação , Eletroforese Capilar/métodos , Eletroforese em Gel de Poliacrilamida , Etilmaleimida , Indicadores e Reagentes , Dodecilsulfato de Sódio/química
20.
J Chromatogr A ; 1680: 463409, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-35998551

RESUMO

Glycosylation is one of the most ubiquitous post-translational modifications (PTM) of proteins. Although the ionization efficiency of native glycans is fairly low, with the assistance of chemical derivation strategies, mass spectrometry (MS) has been extensively used in glycomics because of its high sensitivity, accuracy, and speed. In this study, a novel glycan labelling reagent, (4-hydrazidebutyl) triphenylphosphonium bromide (P4HZD), with a permanent positive charge was developed. The comprehensive capabilities of P4HZD for MS analysis of oligosaccharides were evaluated in detail using maltodextrin as a standard. This labelling reagent can be used in common biological MS techniques such as matrix-assisted laser desorption ionization (MALDI) and electrospray ionization (ESI) mass spectrometry. The MS signal intensity of maltodextrin species could be enhanced up to 96-fold in MALDI-MS by labelling with P4HZD, making P4HZD favorable for MALDI-MS-based high-throughput screening of oligosaccharides. Moreover, P4HZD-labelled oligosaccharides with a degree of polymerization (DP) from 1 to 18 could be separated and analysed by capillary electrophoresis (CE) combined with positive ion mode ESI-MS. In comparison with a commercialized oligosaccharide tag, Girard's reagent P (GirP), P4HZD was more effective for enhancing the signal of oligosaccharides in the middle or higher mass range using both ESI and MALDI ion sources. Two biologics, immunoglobulin G 2 (IgG 2) and fusion protein (FP), were chosen as model complex biological samples to test the efficacy of detection and separation of oligosaccharides by MALDI-MS and CE-ESI-MS analysis with P4HZD labelling. The results indicated that P4HZD is a promising labelling reagent for the detection of oligosaccharides in complex biological samples. The tandem workflow combines the strengths of MALDI-MS and CE-ESI-MS to fulfil the analytical demands of high-throughput screening, while affording good separation.


Assuntos
Hidrazinas , Espectrometria de Massas por Ionização por Electrospray , Eletroforese Capilar , Imunoglobulina G/química , Indicadores e Reagentes , Oligossacarídeos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
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