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1.
J Am Soc Mass Spectrom ; 35(5): 960-971, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38616559

RESUMO

In Asia, some herbal preparations have been found to be adulterated with undeclared synthetic medicines to increase their therapeutic efficiency. Many of these adulterants were found to be toxic when overdosed and have been documented to bring about severe, even life-threatening acute poisoning events. The objective of this study is to develop a rapid and sensitive ambient ionization mass spectrometric platform to characterize the undeclared toxic adulterated ingredients in herbal preparations. Several common adulterants were spiked into different herbal preparations and human sera to simulate the clinical conditions of acute poisoning. They were then sampled with a metallic probe and analyzed by the thermal desorption-electrospray ionization mass spectrometry. The experimental parameters including sensitivity, specificity, accuracy, and turnaround time were prudently optimized in this study. Since tedious and time-consuming pretreatment of the sample is unnecessary, the toxic adulterants could be characterized within 60 s. The results can help emergency physicians to make clinical judgments and prescribe appropriate antidotes or supportive treatment in a time-sensitive manner.


Assuntos
Contaminação de Medicamentos , Preparações de Plantas , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização por Electrospray/métodos , Humanos , Preparações de Plantas/análise , Preparações de Plantas/química , Serviços Médicos de Emergência/métodos
2.
Food Chem ; 417: 135951, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36934712

RESUMO

In this study, we demonstrated a novel semi-automated in-syringe-based coagulant-assisted liquid-liquid microextraction (IS-CGA-LLME) as fast mycotoxin extraction (FaMEx) technique coupled with ultra-high-performance liquid chromatography connected with a tandem-mass spectrometer (UHPLC-MS/MS) for the quantification of mycotoxin (Ochratoxin A, OT-A) in coffee and tea samples. IS-CGA-LLME is a three-step extraction process that includes extraction of OT-A from sample matrix using low-volume solvent extraction, then the extractant was cleaned-up using a coagulation process, and finally, the decolorized/matrix removed sample solution was processed for LLME for target analyte's pre-concentration. The final extractant was analyzed using UHPLC-MS/MS for OT-A quantification. Under the optimized experimental conditions, highly sensitive detection and quantification limits were obtained at 0.001 and 0.003 ng g-1 for OT-A with excellent extraction recovery (93-111%) and precision <10%. These results proved that the developed method is a simple, highly sensitive, semi-automated, low-matrix effect and efficient procedure for the determination of mycotoxins in food samples.


Assuntos
Micotoxinas , Micotoxinas/análise , Cromatografia Líquida de Alta Pressão/métodos , Café/química , Espectrometria de Massas em Tandem/métodos , Seringas , Chá
3.
Molecules ; 28(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36771116

RESUMO

In this work, a fast mycotoxin extraction (FaMEx) technique was developed for the rapid identification and quantification of carcinogenic ochratoxin-A (OTA) in food (coffee and tea) and agricultural soil samples using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) detection. The FaMEx technique advancement is based on two plastic syringes integrated setup for rapid extraction and its subsequent controlled clean-up process. In the extraction process, a 0.25-g sample and extraction solvent were added to the first syringe barrel for the vortex-based extraction. Then, the extraction syringe was connected to a clean-up syringe (pre-packed with C18, activated carbon, and MgSO4) with a syringe filter. Afterward, the whole set-up was placed in an automated programmable mechanical set-up for controlled elution. To enhance FaMEx technology performance, the various influencing sample pretreatment parameters were optimized. Furthermore, the developed FaMEx method indicated excellent linearity (0.9998 and 0.9996 for coffee/tea and soil) with highly sensitive detection (0.30 and 0.29 ng/mL for coffee/tea and soil) and quantification limits (1.0 and 0.96 for coffee/tea and soil), which is lower than the toxicity limit compliant with the European Union regulation for OTA (5 ng/g). The method showed acceptable relative recovery (84.48 to 100.59%) with <7.34% of relative standard deviation for evaluated real samples, and the matrix effects were calculated as <-13.77% for coffee/tea and -9.7 for soil samples. The obtained results revealed that the developed semi-automated FaMEx/UHPLC-MS/MS technique is easy, fast, low-cost, sensitive, and precise for mycotoxin detection in food and environmental samples.


Assuntos
Micotoxinas , Ocratoxinas , Cromatografia Líquida de Alta Pressão/métodos , Micotoxinas/análise , Ocratoxinas/análise , Espectrometria de Massas em Tandem/métodos , Café/química , Seringas , Solo , Chá/química
4.
Healthcare (Basel) ; 10(8)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35893212

RESUMO

Shift work disrupts an otherwise normal circadian rhythm, which may result in sleepiness among night-shift workers. Artificial light has been shown to alter the light-dark cycle of shift workers and reset or phase shift the biological clock, improving nighttime alertness in workers. However, the effect of light therapy on improving sleepiness in nighttime workers has not been effectively confirmed in nursing clinical studies, and it is worth using relevant studies to provide the best evidence in any clinical setting. Systematic review and meta-analysis were used. The study was performed using PRISMA. Academic Search Complete, Embase, MEDLINE, the Cochrane Library, and CINAHL were searched, from the inception of each database to 27 December 2021. The Cochrane risk of bias tool was used to assess the methodological quality of each study. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were synthesized using a random-effects model to assess the efficacy of lighting intervention to improve sleepiness in night-shift workers. Sensitivity analysis followed by subgroup analysis was employed to examine heterogeneity. The meta-analysis was performed using Review Manager 5.4.1 software. A total of 14 studies from 7 countries were included. The overall result shows that lighting interventions significantly improved sleepiness. Further, the blue-enriched white light with a color temperature greater than 5000 Kelvin was effective in improving sleepiness of night-shift workers. This study unveils the emergent knowledge that light interventions with blue-enriched white were effective in improving sleepiness for night-shift workers, including nurses. This finding can be applied to ensure patient safety, reduce accidents, and improve work efficiency and job satisfaction. Nurses constitute the largest health professional workforce. We suggest that hospitals can insert blue-enriched white light equipment for night-shift healthcare providers. Several evidence-based suggestions are made for further consideration.

5.
J Food Drug Anal ; 27(2): 415-427, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30987713

RESUMO

The unintentional ingestion of toxic compounds in herbs is not uncommon in many parts of the world. To provide timely and life-saving care in the emergency department, it is essential to develop a point-of-care analytical method that can rapidly identify these toxins in herbs. Since electrospray laser desorption ionization mass spectrometry (ELDI/MS) has been successfully used to characterize non-volatile chemical compounds without sample preparation, it was used to identify toxic herbal compounds in this study. The herbal toxins were collected either by sweeping a metallic probe across the surface of a freshly cut herb section or by directly sampling extracts of ground herbal powder. The analytes on the probe were then desorbed, ionized and detected using ELDI/MS, wherein analysis of the herbal toxins was completed within 30 s. This approach allows for the rapid morphological recognition of herbs and early point-of-care identification of herbal toxins for emergency management and is promising in providing important toxicological information to ensure appropriate medical treatment.


Assuntos
Serviços Médicos de Emergência , Plantas Tóxicas/química , Toxinas Biológicas/análise , Aconitina/análogos & derivados , Aconitina/análise , Flavanonas/análise , Humanos , Piridoxina/análogos & derivados , Piridoxina/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
6.
Anal Chim Acta ; 1049: 1-9, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30612639

RESUMO

A simple and cheap design for interfacing thin layer chromatography (TLC) with electrospray ionization mass spectrometry (ESI/MS) was developed to scan and characterize compounds on TLC plate. The developed TLC plate was rapidly and easily modified into two sawtooth-edged pieces that were positioned on an XYZ stage so that one of the triangular tips was pointed toward the MS inlet. A drop of methanol and high DC voltage was applied at the tip to induce ESI. After the analytes in the first tip were analyzed, the TLC piece was moved so that the second triangular tip was pointed toward the MS inlet for analysis. The process was repeated until all the triangular tips on the piece were analyzed. In this manner, the analytes, no matter visible or non-visible bands, were scanned and characterized. Since a 4.8 cm long TLC track were cut to 32 triangles on two sawtooth pieces for analysis, the spatial resolution of using the sawtooth TLC-ESI/MS for analysis is 1.5 mm/band. A mixture of dye standards and Datura metel flower extract was analyzed to demonstrate the capability of sawtooth TLC-ESI/MS on scanning and characterizing chemical compounds on the TLC plates. The limits of detection of the dye standards were between 0.25 and 2.5 ng/band. TLC bands containing alkaloids such as scopolamine and norscopolamine from the Datura metel flower extract were not visualized on the developed TLC track, but were successfully detected at different triangular tips using sawtooth TLC-ESI/MS. Based on these results, the Rf values of scopolamine and norscopolamine were determined.


Assuntos
Cromatografia em Camada Fina/métodos , Corantes/análise , Extratos Vegetais/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Cromatografia em Camada Fina/instrumentação , Datura metel/química , Técnicas Eletroquímicas/métodos , Flores/química , Limite de Detecção , Escopolamina/análise , Derivados da Escopolamina/análise
7.
Anal Chem ; 87(3): 1743-8, 2015 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-25562530

RESUMO

A dual ionization source combining electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) was developed to simultaneously ionize both polar and nonpolar compounds. The source was constructed by inserting a fused silica capillary into a stainless steel column enclosed in a glass tube. A high dc voltage was applied to a methanol solution flowing in the fused silica capillary to generate an ESI plume at the capillary tip. A high ac voltage was applied to a ring electrode attached to the glass tube to generate plasma from the nitrogen gas flowing between the glass tube and the stainless steel column. The concentric arrangement of the ESI plume and the APCI plasma in the source ensured that analytes entering the ionization region interacted with both ESI and APCI primary ion species generated in the source. Because the high voltages required for ESI and APCI were independently applied and controlled, the dual ion source could be operated in ESI-only, APCI-only, or ESI+APCI modes. Analytes were introduced into the ESI and/or APCI plumes by irradiating sample surfaces with a continuous-wavelength laser or a pulsed laser beam. Analyte ions could also be produced by directing the dual ESI+APCI source toward sample surfaces for desorption and ionization. The ionization mechanisms involved in the dual ion source include Penning ionization, ion molecule reactions, and fused-droplet electrospray ionization. Standards of polycyclic aromatic hydrocarbons, angiotensin I, lidocaine, ferrocene, diesel, and rosemary oils were used for testing. Protonated analyte ions were detected in ESI-only mode, radical cations were detected in APCI-only mode, and both types of ions were detected in ESI+APCI mode.


Assuntos
Compostos Ferrosos/análise , Fragmentos de Peptídeos/análise , Óleos de Plantas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Pressão Atmosférica , Cromatografia Líquida de Alta Pressão , Humanos , Metalocenos , Espectrometria de Massas por Ionização por Electrospray/instrumentação
8.
Rapid Commun Mass Spectrom ; 21(20): 3311-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17879387

RESUMO

In this study, we discover that hemoglobins (Hb), highly water-soluble globular proteins that are the most predominant proteins detected by matrix-assisted laser desorption ionization/time-of-flight (MALDI-TOF) mass spectrometry in blood, can be used as protein biomarkers for fecal occult blood (FOB). Hemoglobins were extracted from the feces with pure water and separated from the solids in feces through centrifugation. Singly charged molecular ions of Hb-related alpha chains (theoretical MW: 15 126) and beta chains (theoretical MW: 15 867) were detected by MALDI-TOF operated in linear mode using 4-hydroxy-alpha-cyanocinnamic acid (alpha-CHC) as the matrix (with a volumetric ratio of 1:1). The detection limit of FOB using this method is estimated to be lower than 0.1 microg blood per mg of feces, which is approximately 10 to 100 times lower than that of the conventional chemical approaches. The foods and dietary supplements that commonly interfere with the conventional chemical assays of FOB - such as animal blood food products and tablets containing iron and vitamin C - do not interfere with the detection of Hb biomarkers during MALDI-TOF analysis.


Assuntos
Fezes/química , Hemoglobinas/análise , Sangue Oculto , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Biomarcadores/análise , Humanos
9.
Rapid Commun Mass Spectrom ; 21(3): 375-84, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17206740

RESUMO

We describe the use of electrospray-assisted pyrolysis ionization/mass spectrometry (ESA-Py/MS) to selectively ionize trace polar compounds that coexist with large amounts of nonpolar hydrocarbons in crude oil, amber, humic substances, and rubber samples. Samples of different origins are distinguished rapidly by their positive ion ESA-Py mass spectra without prior separation or chemical pretreatment. During ESA-Py analysis, the samples in their solid or liquid states were pyrolyzed at 590, 630 or 940 degrees C using a commercial Curie-point pyrolysis probe. The gaseous pyrolysates were transferred into a glass reaction cell. The polar compounds (M) in the pyrolysates were then ionized by electrospray ionization (ESI), yielding protonated molecules (MH+). Although the major components of the pyrolysates are nonpolar hydrocarbons, their lack of functional groups that can receive a proton in the ESA-Py source results in no hydrocarbon ion signals being produced; thus, the positive ions detected in ESA-Py mass spectra all result from trace polar components in the pyrolysates.


Assuntos
Âmbar/química , Temperatura Alta , Substâncias Húmicas/análise , Petróleo/análise , Polímeros/análise , Borracha/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Âmbar/análise , Sistemas Computacionais , Microquímica/instrumentação , Microquímica/métodos , Reprodutibilidade dos Testes , Borracha/análise , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray/instrumentação
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