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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.
Anal Chim Acta ; 1296: 342343, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38401934

RESUMO

Mushroom poisoning occurs frequently after the ingestion of toxic wild mushrooms misidentified as edible species. The goal of this study is to develop a mass spectrometric platform to bypass the need for morphological recognition of poisonous mushrooms by experts and rapidly identify the toxins in the mushrooms for emergency care. Trace mushroom toxins were collected by penetrating and removing the mushrooms surface for 3 mm with a direct electrospray probe (DEP). The analytes on the DEP were then dissolved in the solution (70% isopropanol containing 0.1% acetic acid) flowing out of a solvent reservoir on the DEP. Electrospray ionization was induced from the sample solution as a high electric field was generated between the DEP and MS inlet. The obtaining mass spectrometric results were further analyzed with principal component analysis (PCA) to classify mushroom toxins. The mass spectrometric platform for detecting mushroom toxins was assessed for its sensitivity, precision, and efficiency by determining its limit-of-detection (LOD), repeatability, and turnaround time, respectively. As a result, the LODs of the mushroom toxins in pure methanol and spiked in human vomitus by DEP/MS were within 0.001-0.5 ng/µL and 0.01-1 ng/µL, respectively. Linear responses of the mushroom toxins in pure methanol with concentrations between 0.01 and 5 ng/µL (R2 between 0.9922 and 0.998) were obtained. The repeatability of the approach (n = 10) was shown in the low relative standard deviation value (<15%) from ten repeat analysis of mushroom toxins standard solution. The corresponding toxic compounds were identified through matching of the obtained mass spectrometric data with those provided by its companion database library of mushroom toxins. Since no time-consuming pretreatment of the samples is required, identification of mushroom toxins with DEP/MS was complete within 1 min. This will be helpful for the emergency physicians to make correct clinical judgment and prescribe appropriate medical treatment in a timely manner.


Assuntos
Agaricales , Serviços Médicos de Emergência , Micotoxinas , Humanos , Metanol , Espectrometria de Massas
3.
J Food Sci Technol ; 60(7): 1992-2000, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37206414

RESUMO

Identifying the risk of ochratoxin A in our daily food has become fundamental because of its toxicity. In this work, we report a novel semi-automated in-syringe-based fast mycotoxin extraction (IS-FaMEx) technique coupled with direct-injection electrospray-ionization tandem mass spectrometer (ESI-MS/MS) detection for the quantification of ochratoxin A in coffee and tea samples. Under the optimized conditions, the results reveal that the developed method's linearity was more remarkable, with a correlation coefficient of > 0.999 and > 92% extraction recovery with a precision of 6%. The detection and quantification limits for ochratoxin A were 0.2 and 0.8 ng g-1 for the developed method, respectively, which is lower than the European Union regulatory limit of toxicity for ochratoxin-A (5 ng g-1) in coffee. Furthermore, the newly developed modified IS-FaMEx-ESI-MS/MS exhibited lower signal suppression of 8% with a good green metric score of 0.64. In addition, the IS-FaMEx-ESI-MS/MS showed good extraction recovery, matrix elimination, good detection, and quantification limits with high accuracy and precision due to the fewer extraction steps with semi-automation. Therefore, the presented method can be applied as a potential methodology for the detection of mycotoxins in food products for food safety and quality control purposes. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05733-z.

4.
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
5.
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
6.
Environ Res ; 217: 114787, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36410459

RESUMO

Nicotine is the most prominent psychoactive/addictive chemical substance consumed worldwide among young players in team sports. Moreover, urinary nicotine discharge and nicotine-based products disposal in environmental waters has been unavoidable in recent years. Therefore, sensitive monitoring of nicotine content in environmental waters and human urine samples is essential. In this study, we developed a miniaturized novel green, low-cost, sensitive, in-syringe-based semi-automated fast drug extraction (FaDEx) protocol coupled with gas chromatography-flame ionization detection (GC-FID) for the efficient environmental and bio-monitoring of nicotine in aqueous samples. The FaDEx method consists of two steps; firstly, the target analyte was extracted using dimethyl carbonate (a green solvent) and extraction salts. After that, the extraction solvent was passed automatically through the solid-phase extraction cartridge at a constant flow rate for the cleanup process to achieve the sensitive nicotine analysis by GC-FID. Under optimized experimental conditions, the developed method showed excellent linearity over the concentration ranges between 20-2000 ng mL-1 with a correlation coefficient >0.99. The detection and quantification limits were 4 and 20 ng mL-1, respectively. The presented method was applied to monitor and assess nicotine exposure in sports-persons' urine and environmental water samples. The method accuracy and precision in terms of relative recovery and relative standard deviation (for triplicate analysis) were 85.4-110.2% and ≤8%, respectively. Finally, the impact of our procedure on the environment from a green analytical chemistry view was assessed using a novel metric system called AGREE, and obtained the greenness score of 0.87, indicating its an efficient alternative green analytical protocol for routine environmental and bio-monitoring of nicotine in environmental and biological samples.


Assuntos
Nicotina , Água , Humanos , Nicotina/análise , Monitoramento Biológico , Limite de Detecção , Extração em Fase Sólida/métodos , Solventes , Psicotrópicos/análise
7.
Environ Res ; 217: 114823, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36402184

RESUMO

In this work, we demonstrated a new, environmental-friendly and effective sample preparation strategy named 'in-syringe-assisted fast pesticides extraction (FaPEx)' technique coupled with LC-MS/MS for the rapid identification and monitoring of emerging pollutant fipronil and its metabolite fipronil sulfone in chicken egg and environmental soil samples. FaPEx strategy comprising of two simple steps. Firstly, the sample was placed in the syringe and extracted using low-volume acetonitrile with NaCl and anhydrous MgSO4 salts. Secondly, the extractant was passed through in-syringe-based solid-phase extraction (SPE) kit containing cleanup sorbents and salt combinations (C18, primary secondary amine, and anhydrous MgSO4) for the cleanup process. Then, the obtained clean extractant was injected into LC-MS/MS for the quantification of target analytes. Various important parameters influencing the FaPEx performances, such as solvent type, salt type, salt amount, sorbent type, and amount, were examined and optimized. The method validation results showed excellent linearity with high correlation coefficients were ≥ 0.99. The estimated LODs were between 0.05-0.07 µg/kg, and LOQs ranged between 0.1-0.25 µg/kg for target analytes in both egg and soil sample matrices, and precision values were ≤7.90%. The developed method was applied to commercial chicken egg samples and environmental soil samples analysis. Spiked recoveries ranged between 88.75-110.91% for egg samples with RSDs ≤7.42% and 82.47-107.46% for soil samples with RSDs <7.37%. These results proved that the developed sample preparation method is a simple, fast, green, low-cost, and efficient method for the analysis of fipronil and its metabolites in food and environmental samples. Thus, this method can be applied as an alternative analytical methodology in routine and standard food and environmental testing laboratories.


Assuntos
Poluentes Ambientais , Praguicidas , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida , Cromatografia Líquida de Alta Pressão/métodos , Extração em Fase Sólida/métodos , Solo
8.
Mass Spectrom Rev ; 42(5): 1828-1847, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35603997

RESUMO

In the emergency department, it is important to rapidly identify the toxic substances that have led to acute poisoning because different toxicants or toxins cause poisoning through different mechanisms, requiring disparate therapeutic strategies and precautions against contraindicating actions, and diverse directions of clinical course monitoring and prediction of prognosis. Ambient ionization mass spectrometry, a state-of-the-art technology, has been proved to be a fast, accurate, and user-friendly tool for rapidly identifying toxicants like residual pesticides on fruits and vegetables. In view of this, developing an analytical platform that explores the application of such a cutting-edge technology in a novel direction has been initiated a research program, namely, the rapid identification of toxic substances which might have caused acute poisoning in patients who visit the emergency department and requires an accurate diagnosis for correct clinical decision-making to bring about corresponding data-guided management. This review includes (i) a narrative account of the breakthrough in emergency toxicology brought about by the advent of ambient ionization mass spectrometry and (ii) a thorough discussion about the clinical implications and technical limitations of such a promising innovation for promoting toxicological tests from tier two-level to tier one level.

9.
Rapid Commun Mass Spectrom ; 36(24): e9409, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36194496

RESUMO

Flame-induced atmospheric pressure chemical ionization (FAPCI) has been used to directly characterize chemical compounds on a glass rod and drug tablet surfaces. In this study, FAPCI was further applied to interface thin layer chromatography (TLC) and mass spectrometry (MS) for mixture analysis. METHODS: A micro-sized oxyacetylene flame was generated using a small concentric tube system. Hot gas flow and primary reactive species from the micro-flame were directed toward a developed TLC gel plate to thermally desorb and ionize analytes on the gel surface. The resulting analyte ions subsequently entered the MS inlet for detection. RESULTS: A 1-1.5-mm-wide light-brown line was observed on the TLC plate after the desorption FAPCI/MS (DFAPCI/MS) analysis, revealing that the gel surface withstood a high temperature from the impact of the micro-flame. Volatile and semi-volatile chemical compounds, including amine and amide standards, drugs, and aromatherapy oils, were successfully desorbed, ionized, and detected using this TLC/DFAPCI/MS. The limit of detection of TLC-DFAPCI/MS was determined to be 5 ng/spot for dibenzylamine and ethenzamide. CONCLUSIONS: TLC/DFAPCI/MS is one of the simplest TLC-MS interfaces showing the advantages such as low costs and an easy set up. The technique is useful for characterizing thermally stable volatile and semi-volatile compounds in a mixture.


Assuntos
Pressão Atmosférica , Cromatografia em Camada Fina/métodos , Espectrometria de Massas/métodos , Comprimidos
10.
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.

12.
Rapid Commun Mass Spectrom ; 36(18): e9351, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-35802517

RESUMO

RATIONALE: Thermogravimetry (TG) combined with electrospray and atmospheric chemical ionization (ESI+APCI) mass spectrometry (MS) was developed to rapidly characterize thermal decomposition products of synthetic polymers and plastic products. The ESI-based TG-MS method is useful for characterizing thermally labile, nonvolatile, and polar compounds over an extensive mass range; and the APCI-based TG-MS counterpart is useful for characterizing volatile and nonpolar compounds. Both polar and nonpolar compounds can be simultaneously detected by ESI+APCI-based TG-MS. METHODS: Analytes with different volatility were produced from TG operated at different temperatures, which were delivered through a heated stainless-steel tube to the ESI+APCI source where they reacted with the primary charged species generated from electrospray and atmospheric pressure chemical ionization (ESI+APCI) of solvent and nitrogen. The analyte ions were then detected by an ion trap mass spectrometer. RESULTS: A semi-volatile PEG 600 standard was used as the sample and protonated and sodiated molecular ions together with adduct ions including [(PEG)n + 15]+ , [(PEG)n + 18]+ , and [(PEG)n + 29]+ were detected by TG-ESI+APCI-MS. The technique was further utilized to characterize thermal decomposition products of nonvolatile polypropylene glycol (PPG) and polystyrene (PS) standards, as well as a PS-made water cup and coffee cup lid. The characteristic fragments of PPG and PS with mass differences of 58 and 104 between respective ion peaks were detected at the maximum decomposition temperature (Tmax ). CONCLUSIONS: The information obtained from the TG-ESI+APCI-MS analysis is useful in rapidly distinguishing different types of polymers and their products. In addition, the signals of the additives in the polymer products, including antioxidants and plasticizers, were also detected before the TG temperature reached Tmax .


Assuntos
Pressão Atmosférica , Espectrometria de Massas por Ionização por Electrospray , Polímeros , Solventes , Espectrometria de Massas por Ionização por Electrospray/métodos , Termogravimetria
13.
J Food Drug Anal ; 30(1): 26-37, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35647718

RESUMO

Despite the fact that carbamates and organophosphates cause acute poisoning via different mechanisms and require disparate management, they are indistinguishable by current clinical assays. Herein, direct immersion solid-phase microextraction (DI-SPME) plus thermal desorption-electrospray ionization tandem mass spectrometry (TD-ESI/MS/MS) was developed to discern them. Both pesticides spiked in human serum were extracted by SPME and analyzed by TD-ESI/MS/MS. This is a promising emergency care platform as rapid analyses could be done in tiny sample volumes with satisfactory recovery (89.46%-116.32%), precision (covariance <20%), sensitivity (LOD <0.1 µg/mL), turnaround time (<5 minutes), and linearity (R2 = 0.9827-0.9992) within 0.1-100 µg/mL.


Assuntos
Praguicidas , Microextração em Fase Sólida , Humanos , Imersão , Praguicidas/análise , Microextração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
14.
Front Psychiatry ; 13: 577857, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35509884

RESUMO

Objectives: Isobaric tags for relative and absolute quantitation (iTRAQ) is a proteomic investigation that could be utilized for rapid identification and quantification of proteins, which we would use to identify differentially expressed proteins in treatment responsive patients with major depressive disorder (MDD). Methods: Six treatment responsive patients of MDD were recruited, and their peripheral blood mononuclear cell (PBMC) were collected before and after 4 weeks of paroxetine treatment. iTRAQ and Mascot search engine were used to detect differentially expressed proteins, which were then validated by Western blot. Results: Two thousand one hundred and fifty three proteins were screened, and seven proteins showed differences of more than two-fold and 62 proteins with a differences of less than two-fold. Six proteins with commercially available antibodies were identified, and were validated by Western blot in 10 paroxetine responsive MDD patients. Putative hydroxypyruvate isomerase (HYI), eukaryotic translation initiation factor 4H (eIF4H), and RNA binding motif 8A (RBM8A) had statistically significant differences before and after treatment in the validation. Data are available via ProteomeXchange with identifier PXD028947. Conclusions: By using iTRAQ and Western blot, we were able to identify HYI, eIF4H, and RAM8a to be the potential predictors of paroxetine treatment response in patients with MDD. This finding could help establish future individualized medicine.

15.
Molecules ; 27(9)2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35566120

RESUMO

Ambient ionization mass spectrometry (AIMS) is both labor and time saving and has been proven to be useful for the rapid delineation of trace organic and biological compounds with minimal sample pretreatment. Herein, an analytical platform of probe sampling combined with a thermal desorption-electrospray ionization/mass spectrometry (TD-ESI/MS) and multivariate statistical analysis was developed to rapidly differentiate bacterial species based on the differences in their lipid profiles. For comparison, protein fingerprinting was also performed with matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) to distinguish these bacterial species. Ten bacterial species, including five Gram-negative and five Gram-positive bacteria, were cultured, and the lipids in the colonies were characterized with TD-ESI/MS. As sample pretreatment was unnecessary, the analysis of the lipids in a bacterial colony growing on a Petri dish was completed within 1 min. The TD-ESI/MS results were further performed by principal component analysis (PCA) and hierarchical cluster analysis (HCA) to assist the classification of the bacteria, and a low relative standard deviation (5.2%) of the total ion current was obtained from repeated analyses of the lipids in a single bacterial colony. The PCA and HCA results indicated that different bacterial species were successfully distinguished by the differences in their lipid profiles as validated by the differences in their protein profiles recorded from the MALDI-TOF analysis. In addition, real-time monitoring of the changes in the specific lipids of a colony with growth time was also achieved with probe sampling and TD-ESI/MS. The developed analytical platform is promising as a useful diagnostic tool by which to rapidly distinguish bacterial species in clinical practice.


Assuntos
Bactérias , Espectrometria de Massas por Ionização por Electrospray , Lipídeos , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
16.
Chemosphere ; 303(Pt 1): 134896, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35561770

RESUMO

Ambient mass spectrometry thermal desorption-electrospray ionization/mass spectrometry (TD-ESI/MS) can rapidly identify chemicals without pretreatment of biological samples. This study used a rapid semi-quantitative TD-ESI/MS screening technique for the probe skin sampling of melamine workers occupationally exposed to different ambient melamine concentrations to create avatar-like body images, which were then used to study temporal and dynamic changes in nephrotoxic melamine exposure. We enrolled four voluntary melamine workers from one factory, each from one of four worksites. Melamine exposure was highest in manufacturing and molding, followed by grinding and polishing, packing, and administration, the lowest. Skin samples were collected Friday (end-of-shift) and Monday (pre-shift). Early morning one-spot urine samples were also collected right after skin sampling. 2198 probe skin samples were collected and subjected to semi-quantitative TD-ESI/MS analyses of melamine chemical within 40 h. After normalization, converted body image scores revealed exposure to be highest in the manufacturing worker on Friday and lowest in the administrative worker on Monday. The absolute differences (Friday minus Monday) of normalized body image scores were all significantly positive in each individual worker and across all four workers (permutation test, all p-values < 0.002). The slope estimates of the linear regression line between body image scores and urinary melamine levels were 0.81 (p-value = 0.008). We concluded that this fast and non-invasive technique can potentially be used to study temporal and dynamic changes in exposure to occupational hazards. A future study of developing an automatic and reproducible TD-ESI/MS sampling platform is needed.


Assuntos
Espectrometria de Massas por Ionização por Electrospray , Triazinas , Humanos , Modelos Lineares , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
17.
Anal Chim Acta ; 1200: 339611, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35256141

RESUMO

A simple flame-induced atmospheric pressure chemical ionization (FAPCI) source was developed to couple a gas chromatograph (GC) with a mass spectrometer (MS). The interface consisted of a heated transfer line and a high voltage-free ambient FAPCI source. Nitrogen gas flowing through the heated transfer line was utilized to deliver the analytes eluted from a GC column to the ionization region. A micro oxyacetylene flame was positioned under the exit of heated transfer line, which generated primary charged species in the ionization region. Since the temperature at the ionization region was below 200 °C, the analytes were not thermally decomposed. Protonated analytes were formed by reacting the analytes with flame-induced charged species through ion-molecule reactions (IMRs). The simple GC-FAPCI/MS was used to characterize a series of fatty acid methyl esters (FAMEs) and long-chain normal alkanes, which showed protonated FAME and oxidized n-alkane ions on the mass spectra. The limits of detection (LODs) for C15:0 to C25:0 FAMEs were 1-2.5 pg. A calibration curve ranging from 2.5 to 500 pg, with a R2 value of 0.9821, was obtained.


Assuntos
Pressão Atmosférica , Ácidos Graxos , Ésteres/análise , Ácidos Graxos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos , Espectrometria de Massas
18.
Anal Chem ; 93(49): 16608-16617, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34860507

RESUMO

Squalene (SQ), a highly unsaturated sebaceous lipid, plays an important role in protecting human skin. To better understand the role of SQ in clinical medicine, an efficient analytical approach is needed to comprehensively study the distribution of SQ on different parts of the skin. In this study, sebaceous lipids were collected from different epidermal areas of a volunteer with sampling probes. Thermal desorption-electrospray ionization/mass spectrometry (TD-ESI/MS) was then used to characterize the lipid species on the probes, and each TD-ESI/MS analysis was completed within a few seconds without any sample pretreatment. The molecular mapping of epidermal squalene on whole-body skin was rendered by scaling the peak area of the extracted ion current (EIC) of SQ based on a temperature color gradient, where colors were assigned to the 1357 sampling locations on a 3D map of the volunteer. The image showed a higher SQ distribution on the face than any other area of the body, indicating the role of SQ in protecting facial skin. The results were in agreement with previous studies using SQ as a marker to explore sebaceous activity. The novelty and significance of this work are concluded as two points: (1) direct and rapid detection of all major classes of sebaceous lipids, including the unsaturated hydrocarbons (SQ) and nonpolar lipids (e.g., cholesterol). The results are unique compared to other conventional and ambient ionization mass spectrometry methods and (2) this is the first study to analyze SQ distribution on the whole-body skin by a high-throughput approach.


Assuntos
Epiderme , Esqualeno , Humanos , Lipídeos , Espectrometria de Massas , Pele
19.
Molecules ; 26(15)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34361610

RESUMO

Matrix-assisted laser desorption ionization/time-of-flight (MALDI-TOF) mass spectrometry is a sensitive analytical tool for characterizing various biomolecules in biofluids. In this study, MALDI-TOF was used to characterize potential plasma biomarkers for distinguishing patients with major depressive disorder (MDD) from patients with schizophrenia and healthy controls. To avoid interference from albumin-the predominant protein in plasma-the plasma samples were pretreated using acid hydrolysis. The results obtained by MALDI-TOF were also validated by electrospray ionization-quadrupole time-of-flight (ESI-QTOF) mass spectrometry. The analytical results were further treated with principal component analysis (PCA), hierarchical clustering analysis (HCA), and receiver operating characteristic (ROC) curve analysis. The statistical analyses showed that MDD patients could be distinguished from schizophrenia patients and healthy controls by the lack of apolipoprotein C1 (Apo C1), which, in fact, was detected in healthy controls and schizophrenia patients. This protein is suggested to be a potential plasma biomarker for distinguishing MDD patients from healthy controls and schizophrenia patients. Since sample preparation for MALDI-TOF is very simple, high-throughput plasma apolipoprotein analysis for clinical purposes is feasible.


Assuntos
Apolipoproteína C-I/sangue , Biomarcadores/sangue , Transtorno Depressivo Maior/sangue , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
20.
Environ Sci Pollut Res Int ; 28(21): 27333-27344, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33511527

RESUMO

Phthalates can leach into indoor and outdoor airborne particulate matter and dust, which can then be ingested or absorbed and induce lung injury. Dermal phthalate levels can be used as a matrix for exposure direct absorption from air, particle deposition, and contact with contaminated products. However, the association between dermal phthalate levels in skin wipes and lung function tests remains unknown. A total of 397 participants were included. Spirometry measurements of forced expiratory volume in 1 s (FEV1, L) and forced vital capacity (FVC, L) were calculated. Dermal phthalate levels of diethyl phthalate (DMP), diethyl phthalate (DEP), di(n-butyl) phthalate (DnBP), butyl benzyl phthalate (BBzP), di(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DiNP), and diisodecyl phthalate (DiDP) on forehead skin wipes were detected. The one-unit increases in logarithm (log) dermal DnBP (ß = - 0.08; 95% CI - 0.16, - 0.003, p = 0.041), BBzP (ß = - 0.09; 95% CI - 0.16, - 0.02, p = 0.009), DEHP (ß = - 0.07; 95% CI - 0.14, - 0.003, p = 0.042), and DiNP (ß = - 0.08; 95% CI - 0.15, - 0.02, p = 0.017) were significantly associated with decreases in FVC. For elderly participants, one-unit increases in log dermal DnBP (ß = - 0.25; 95% CI - 0.46, - 0.04, p = 0.021), BBzP (ß = - 0.17; 95% CI - 0.33, - 0.01, p = 0.042), and DiDP (ß = - 0.19; 95% CI - 0.39, < 0.01, p = 0.052) were associated with decreases in FEV1. In conclusion, dermal phthalate levels were significantly associated with decreases in lung function tests.


Assuntos
Poluentes Ambientais , Ácidos Ftálicos , Idoso , Poeira , Exposição Ambiental , Humanos , Ácidos Ftálicos/análise , Testes de Função Respiratória
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