Departamento de Química, Faculdade de Filosofia Ciência e Letras de Ribeirão Preto, Universidade de São Paulo, P.O. Box 14040-901 Ribeirão Preto, SP, Brazil.
Molecules. 2019 Apr 27;24(9):1658. doi: 10.3390/molecules24091658.
This work describes the direct coupling of the in-tube solid-phase microextraction (in-tube SPME) technique to a tandem mass spectrometry system (MS/MS) to determine amino acids (AA) and neurotransmitters (NT) (alanine, serine, isoleucine, leucine, aspartic acid, glutamic acid, lysine, methionine, tyrosine, and tryptophan) in plasma samples from schizophrenic patients. An innovative organic-silica hybrid monolithic capillary with bifunctional groups (amino and cyano) was developed and evaluated as an extraction device for in-tube SPME. The morphological and structural aspects of the monolithic phase were evaluated by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), nitrogen sorption experiments, X-ray diffraction (XRD) analyses, and adsorption experiments. In-tube SPME-MS/MS conditions were established to remove matrix, enrich analytes (monolithic capillary) and improve the sensitivity of the MS/MS system. The proposed method was linear from 45 to 360 ng mL for alanine, from 15 to 300 ng mL for leucine and isoleucine, from 12 to 102 ng mL for methionine, from 10 to 102 ng mL for tyrosine, from 9 to 96 ng mL for tryptophan, from 12 to 210 ng mL for serine, from 12 to 90 ng mL for glutamic acid, from 12 to 102 ng mL for lysine, and from 6 to 36 ng mL for aspartic acid. The precision of intra-assays and inter-assays presented CV values ranged from 1.6% to 14.0%. The accuracy of intra-assays and inter-assays presented RSE values from -11.0% to 13.8%, with the exception of the lower limit of quantification (LLOQ) values. The in-tube SPME-MS/MS method was successfully applied to determine the target AA and NT in plasma samples from schizophrenic patients.
本工作描述了将管内固相微萃取（in-tube SPME）技术与串联质谱系统（MS/MS）直接耦合，以测定精神分裂症患者血浆样品中的氨基酸（AA）和神经递质（NT）（丙氨酸、丝氨酸、异亮氨酸、亮氨酸、天冬氨酸、谷氨酸、赖氨酸、蛋氨酸、酪氨酸和色氨酸）。开发并评价了一种具有双官能团（氨基和氰基）的新型有机-硅杂化整体式毛细管作为管内 SPME 的萃取装置。通过扫描电子显微镜（SEM）、傅里叶变换红外光谱（FTIR）、氮气吸附实验、X 射线衍射（XRD）分析和吸附实验对整体相的形态和结构进行了评价。建立了 in-tube SPME-MS/MS 条件，以去除基质、富集分析物（整体式毛细管）并提高 MS/MS 系统的灵敏度。该方法在 45 至 360ng/mL 范围内对丙氨酸、15 至 300ng/mL 范围内对亮氨酸和异亮氨酸、12 至 102ng/mL 范围内对蛋氨酸、10 至 102ng/mL 范围内对酪氨酸、9 至 96ng/mL 范围内对色氨酸、12 至 210ng/mL 范围内对丝氨酸、12 至 90ng/mL 范围内对谷氨酸、12 至 102ng/mL 范围内对赖氨酸和 6 至 36ng/mL 范围内对天冬氨酸具有线性关系。内标和外标分析的精密度呈现 CV 值范围为 1.6%至 14.0%。内标和外标分析的准确度呈现 RSE 值范围为-11.0%至 13.8%，除了定量下限（LLOQ）值之外。该 in-tube SPME-MS/MS 方法成功应用于测定精神分裂症患者血浆样品中的目标 AA 和 NT。
