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1.
Anal Chem ; 96(2): 821-827, 2024 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-38158586

RESUMEN

Fentanyl and its analogues are potent opioids that pose a significant threat to society. Over the last several years, considerable focus has been on the concerning trend of increasing fentanyl usage among drug users. Fentanyl analogues are mainly synthesized to evade analytical detection or increase their potency; thus, very low concentrations are sufficient to achieve a therapeutic effect. In an effort to help combat the synthetic opioid epidemic, developing targeted mass spectrometric methods for quantifying fentanyl and its analogues at ultralow concentrations is incredibly important. Most methods used to analyze fentanyl and its analogues from whole blood require manual sample preparation protocols (solid-phase extraction or liquid-liquid extraction), followed by chromatographic separation and mass spectrometric detection. The main disadvantages of these methods are the tedious sample preparation workflows, resulting in lengthy analysis times. To mitigate these issues, we present a targeted method capable of analyzing 96 samples containing fentanyl, several fentanyl analogues, and a common fentanyl (analogue) precursor simultaneously in 2.4 min per sample. This is possible by using a high-throughput solid phase microextraction workflow on the Concept96 autosampler followed by manual coupling of solid-phase microextraction fibers to the microfluidic open interface for tandem mass spectrometry analysis. Our quantitative method is capable of extremely sensitive analysis, with limits of quantification ranging from 0.002 to 0.031 ng mL-1 and linearity ranging from 0.010 to 25.0 ng mL-1. The method shows very good reproducibility (1-18%), accuracy (81-100%) of calibration and validation points, and good interday reproducibility (6-15%).


Asunto(s)
Fentanilo , Microextracción en Fase Sólida , Fentanilo/análisis , Microextracción en Fase Sólida/métodos , Microfluídica , Reproducibilidad de los Resultados , Analgésicos Opioides/análisis
2.
Rapid Commun Mass Spectrom ; 36(22): e9388, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36039809

RESUMEN

RATIONALE: We evaluated the effect that the spatial positioning of coated-blade spray (CBS) devices with respect to the mass spectrometry (MS) inlet has when coupling to diverse MS platforms (i.e., triple quadrupole, linear ion trap and time of flight). Furthermore, as a proof of concept, we evaluated CBS-MS as a tool for quantitation of fentanyl and four analogues on said instruments. METHODS: Custom-made MS interfaces were made to accurately position the blade in front of the MS inlet. CBS devices, coated with hydrophilic-lipophilic balanced particles, were used for both the optimization of the CBS position and the quantitation of fentanyl and analogues in urine and plasma samples on all instruments. RESULTS: The SCIEX triple quadrupole instrument was the most sensitive to the position of the blade due to the presence of a curtain gas flowing laminarly out of the MS inlet. After optimization, the analytical capabilities of CBS on each instrument were assessed and the results obtained on both SCIEX and Waters platforms matched the performance obtained using a more advanced instrument by ThermoFisher Scientific. Furthermore, excellent figures of merit were attained for the quantitation of fentanyl and analogues on both triple quadrupole and linear ion trap platforms. CONCLUSIONS: We demonstrated that optimization of MS parameters on different instrument vendors and front ends, such as the position of the CBS tip regarding the MS inlet, is vital to exploit the full quantitative potential of this technology. Application of the technology to screen and quantify fentanyl and analogues showed great potential when considering its coupling with portable mass spectrometers for therapeutic drug monitoring and point-of-care applications.


Asunto(s)
Bahías , Fentanilo , Monitoreo de Drogas , Espectrometría de Masas/métodos
3.
Environ Sci Technol ; 54(24): 15789-15799, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33237731

RESUMEN

A novel magnetic blade spray-tandem mass spectrometry (MBS-MS/MS) assay was developed and optimized, and its performance was characterized for the analysis of 204 pesticides from wastewater treatment facility (WWTF) process water. These results were compared and experimentally validated with an untargeted, high-resolution MS (HRMS) approach that employed liquid chromatography (LC)-amenable thin-film microextraction (TFME) devices to further elucidate the fate of pesticides through the WWTF process. As a result of our optimizations, we report an optimized workflow with an extraction time of 10 min, 150 µg of magnetic HLB particles, and 5 s of desorption. Excellent linearity was obtained for 168 of the 204 pesticides in deionized water, where 90% of the quantifiable pesticides had a determination coefficient (R2) of 0.99 across 3 orders of magnitude and 80% had limits of quantification below 0.5 ng/mL. We subsequently applied our optimized MBS-MS/MS method for the analysis of samples collected during the various stages of wastewater treatment from two WWTFs in Southern Ontario. This article presents a new streamlined methodology with a fast turnaround time for analyzing a large panel of pesticides, ultimately providing us the opportunity to evaluate the performance of two WWTFs for their efficacy in removing these toxic chemicals.


Asunto(s)
Plaguicidas , Contaminantes Químicos del Agua , Purificación del Agua , Límite de Detección , Ontario , Plaguicidas/análisis , Espectrometría de Masas en Tándem , Aguas Residuales , Agua , Contaminantes Químicos del Agua/análisis
4.
Anal Bioanal Chem ; 412(21): 5067-5076, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31907589

RESUMEN

Immunosuppressive drugs (ISDs) are primarily administered following solid organ transplant or for treatment of a variety of autoimmune conditions. Their principal function is to suppress the activity of the immune system; however, the levels must be carefully monitored due to adverse effects of over- or underadministration. A technology for rapid quantitative screening, named coated blade spray (CBS), was directly coupled to a triple quadrupole mass spectrometer (MS/MS) to measure the concentration of ISDs (i.e., cyclosporine A, tacrolimus, everolimus, sirolimus) in whole blood samples. We evaluated the stability of replicate measurements over a 10-day period (precision), assessed linearity and limit of quantification, and performed a method comparison against a validated clinical immunoassay (Abbott ARCHITECT). Total interday variation of less than 5% for all target compounds at three different concentrations was achieved. The sensitivity of the method was determined as 0.25, 1, 1, and 2.5 ng/mL for everolimus, sirolimus, tacrolimus, and cyclosporine A, respectively. The concentrations of three immunosuppressive drugs in 284 patient samples (i.e., ~ 95 samples of cyclosporine A, tacrolimus, or sirolimus) obtained using the CBS-MS/MS methodology were compared with concentrations previously quantified on an Abbott ARCHITECT immunoassay system. Our analysis demonstrated significant statistical similarities between both methods. The results demonstrate that CBS-MS/MS is a suitable alternative to conventional methodologies for monitoring of ISDs from whole blood in a clinical setting. Graphical abstract.


Asunto(s)
Inmunosupresores/sangre , Espectrometría de Masas en Tándem/métodos , Cromatografía Liquida/métodos , Monitoreo de Drogas/métodos , Humanos , Reproducibilidad de los Resultados
6.
Nat Ecol Evol ; 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39333394

RESUMEN

Understanding the genetic and fitness consequences of anthropogenic bottlenecks is crucial for biodiversity conservation. However, studies of bottlenecked populations combining genomic approaches with fitness data are rare. Theory predicts that severe bottlenecks deplete genetic diversity, exacerbate inbreeding depression and decrease population viability. However, actual outcomes are complex and depend on how a species' unique demography affects its genetic load. We used population genetic and veterinary pathology data, demographic modelling, whole-genome resequencing and forward genetic simulations to investigate the genomic and fitness consequences of a near-extinction event in the northern elephant seal. We found no evidence of inbreeding depression within the contemporary population for key fitness components, including body mass, blubber thickness and susceptibility to parasites and disease. However, we detected a genomic signature of a recent extreme bottleneck (effective population size = 6; 95% confidence interval = 5.0-7.5) that will have purged much of the genetic load, potentially leading to the lack of observed inbreeding depression in our study. Our results further suggest that deleterious genetic variation strongly impacted the post-bottleneck population dynamics of the northern elephant seal. Our study provides comprehensive empirical insights into the intricate dynamics underlying species-specific responses to anthropogenic bottlenecks.

7.
J Am Soc Mass Spectrom ; 34(6): 1006-1014, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37004172

RESUMEN

Mass spectrometry analysis can be performed by introducing samples directly to mass spectrometry, allowing the increase of the analysis throughput; however, some disadvantages of direct-to-mass spectrometry analysis include susceptibility to matrix effects and risk of instrument contamination from inadequate sample preparation. Solid-phase microextraction is one of the most suitable sample preparation methods for direct-to-mass spectrometry analysis, as it offers matrix-compatible coatings which ensure analyte enrichment with minimal or no interference from matrix. One of the ways solid-phase microextraction can be coupled directly to mass spectrometry is via a microfluidic open interface. This manuscript reports improvements made to the initial microfluidic open interface design, where the system components have been simplified to mostly commercially available materials. In addition, the analysis of samples has been automated by implementing software that fully controls the analysis workflow, where the washing procedure is optimized to completely reduce the carryover. Herein, the extraction and desorption time profiles from thin and thick SPME devices was studied where the overall workflow consisted of high-throughput sample preparation of 1.3 min per 96 samples and <1 min per sample instrumental analysis.

8.
Talanta ; 232: 122438, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34074423

RESUMEN

UPLC-MS/MS methods are the gold standard for routine, high-throughput measurements of biogenic monoamines for the diagnosis of catecholamine-producing tumors. However, this cannot be achieved without employing efficient sample pretreatment methods. Therefore, two pretreatment methods, thin-film solid phase microextraction (TF-SPME) and packed fibers solid phase extraction (PFSPE), were developed and evaluated for the analysis of biogenic monoamines and their metabolites in urine. A hydrophilic-lipophilic balance (HLB) coating was chosen for the thin-film blade format SPME method and compared with a Polycrown ether (PCE) composite nanofiber used as an adsorbent for the PFSPE method. Under optimal conditions, the absolute extraction recovery and relative matrix effect of the newly developed TF-SPME method were determined to be 35.7-74.8% and 0.47-3.63%, respectively. The linearity was 0.25-500 ng mL-1 for norepinephrine, epinephrine, dopamine, normetanephrine 3-methoxytyramine, serotonin, histamine, and 0.1-500 ng mL-1 for metanephrine. The intra-and inter-assay coefficients of variation were 0.7-8.7%, and the respective accuracies were calculated to be 90.8-104.7% and 89.5-104.5% for TF-SPME. Compared with the PFSPE method, the TF-SPME method had a higher extraction efficiency, lower matrix effects and a wider linear range for eight target substances, which ensured higher accuracy of simultaneous detection of all compounds of interest. Therefore, the proposed TF-SPME method can be employed for the high throughput screening for neuroendocrine tumors in a routine clinical setting and other relative research by simultaneous quantitation of urine eight biological monoamines in a single run.


Asunto(s)
Microextracción en Fase Sólida , Espectrometría de Masas en Tándem , Monoaminas Biogénicas , Cromatografía Liquida , Reproducibilidad de los Resultados
9.
Anal Chim Acta ; 1144: 53-60, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33453797

RESUMEN

Immunosuppressive drugs are administered to decrease immune system activity (e.g. of patients undergoing solid organ transplant). Concentrations of immunosuppressive drugs (ISDs) in circulating blood must be closely monitored during the period of immunosuppression therapy due to adverse effects that take place when concentration levels fall outside of the very narrow therapeutic concentration range of these drugs. This study presents the rapid determination of four relevant immunosuppressive drugs (tacrolimus, sirolimus, everolimus, and cyclosporine A) in whole human blood by directly coupling solid-phase microextraction to mass spectrometry via the microfluidic open interface (Bio-SPME-MOI-MS/MS). The BioSPME-MOI-MS/MS method offers ≤ 10% imprecision of in-house prepared quality controls over a 10-day period, ≤ 10% imprecision of ClinCal® Recipe calibrators over a three-day period, and single total turnaround time of ∼ 60 min (4.5 min for high throughput). The limits of quantification were determined to be 0.8 ng mL-1 for tacrolimus, 0.7 ng mL-1 sirolimus, 1.0 ng mL-1 for everolimus, and 0.8 ng mL-1 for cyclosporine. The limits of detection were determined to be 0.3 ng mL-1 for tacrolimus, 0.2 ng mL-1 for sirolimus, 0.3 ng mL-1 for everolimus, and 0.3 ng mL-1 for cyclosporine A. The R2 values for all analytes were above 0.9992 with linear dynamic range from 1.0 mL-1 to 50.0 ng mL-1 for tacrolimus, sirolimus, and everolimus while from 2.5 ng mL-1 to 500.0 ng mL-1 for cyclosporine A. To further evaluate the performance of the present method, 95 residual whole blood samples of tacrolimus and sirolimus from patients undergoing immunosuppression therapy were used to compare the Bio-SPME-MOI-MS/MS method against a clinically validated reference method based on chemiluminescent microparticle immunoassay, showing acceptable results. Our results demonstrated that Bio-SPME-MOI-MS/MS can be considered as a suitable alternative to existing methods for the determination of immunosuppressive drugs in whole blood providing faster analysis, better selectivity and sensitivity, and a wider dynamic range than current existing approaches.


Asunto(s)
Sirolimus , Tacrolimus , Ciclosporina , Monitoreo de Drogas , Humanos , Inmunosupresores , Microfluídica , Microextracción en Fase Sólida , Espectrometría de Masas en Tándem
10.
J Am Soc Mass Spectrom ; 32(4): 956-968, 2021 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-33733774

RESUMEN

The presence of solvent vapor in a differential mobility spectrometry (DMS) cell creates a microsolvating environment that can mitigate complications associated with field-induced heating. In the case of peptides, the microsolvation of protonation sites results in a stabilization of charge density through localized solvent clustering, sheltering the ion from collisional activation. Seeding the DMS carrier gas (N2) with a solvent vapor prevented nearly all field-induced fragmentation of the protonated peptides GGG, AAA, and the Lys-rich Polybia-MP1 (IDWKKLLDAAKQIL-NH2). Modeling the microsolvation propensity of protonated n-propylamine [PrNH3]+, a mimic of the Lys side chain and N-terminus, with common gas-phase modifiers (H2O, MeOH, EtOH, iPrOH, acetone, and MeCN) confirms that all solvent molecules form stable clusters at the site of protonation. Moreover, modeling populations of microsolvated clusters indicates that species containing protonated amine moieties exist as microsolvated species with one to six solvent ligands at all effective ion temperatures (Teff) accessible during a DMS experiment (ca. 375-600 K). Calculated Teff of protonated GGG, AAA, and Polybia-MPI using a modified two-temperature theory approach were up to 86 K cooler in DMS environments seeded with solvent vapor compared to pure N2 environments. Stabilizing effects were largely driven by an increase in the ion's apparent collision cross section and by evaporative cooling processes induced by the dynamic evaporation/condensation cycles incurred in the presence of an oscillating electric separation field. When the microsolvating partner was a protic solvent, abstraction of a proton from [MP1 + 3H]3+ to yield [MP1 + 2H]2+ was observed. This result was attributed to the proclivity of protic solvents to form hydrogen-bond networks with enhanced gas-phase basicity. Collectively, microsolvation provides analytes with a solvent "air bag," whereby charge reduction and microsolvation-induced stabilization were shown to shelter peptides from the fragmentation induced by field heating and may play a role in preserving native-like ion configurations.


Asunto(s)
Espectrometría de Movilidad Iónica/métodos , Péptidos/química , Secuencia de Aminoácidos , Iones , Simulación de Dinámica Molecular , Soluciones , Solventes/química , Electricidad Estática , Temperatura
11.
Anal Chim Acta ; 1075: 112-119, 2019 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-31196416

RESUMEN

Electrospray ionization mass spectrometry (ESI-MS) is a commonly used technique for analysis of various samples. Solid phase microextraction (SPME) is a simple and efficient technique that combines both sampling and sample preparation into one consolidated step, preconcentrating extracted analytes for ultra-sensitive analysis. Historically, SPME has been coupled with chromatography-based techniques for sample separation prior to analysis, however more recently, the chromatographic step has been omitted, with the SPME device directly coupled with the mass spectrometer. In this study, direct coupling of SPME with ESI-MS was developed, and extensively validated to quantitate ketamine from human urine, employing a practical experimental workflow and no extensive hardware modification to the equipment. Among the different fibers evaluated, SPME device coated with C18/benzenesulfonic acid particles was selected for the analysis due to its good selectivity and signal response. Different approaches, including desorption spray, dripping, desorption ESI and nano-ESI were attempted for elution and ionization of the analytes extracted using the SPME fibers. The results showed that the desorption spray and nano-ESI methods offered better signal response and signal duration than the others that were evaluated. The analytical performance of the SPME-nano-ESI-MS setup was excellent, including limit of detection (LOD) of 0.027 ng/mL, limit of quantitation (LOQ) of 0.1 ng/mL, linear range of 0.1-500.0 ng/mL (R2 = 0.9995) and recoveries of 90.8-109.4% with RSD 3.4-10.6% for three validation points at 4.0, 40.0 and 400.0 ng/mL, far better than the performance of conventional methods. The results herein presented, demonstrated that the direct coupling of SPME fibers with ESI-MS-based systems allowed for the simple and ultra-sensitive determination of analytes from raw samples such as human urine.


Asunto(s)
Ketamina/orina , Humanos , Límite de Detección , Microextracción en Fase Sólida/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos
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