Publications by authors named "Joao V B Borsatto"

Nano-liquid chromatography (nanoLC) is gaining significant attention as a primary analytical technique across various scientific domains. Unlike conventional high-performance LC, nanoLC utilizes columns with inner diameters (i.ds.

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This review provides an overview of recent advancements in applying graphene-based materials as sorbents for liquid chromatography (LC) analysis. Graphene-based materials are promising for analytical chemistry, including applications as sorbents in liquid chromatography. These sorbents can be functionalized to produce unique extraction or stationary phases.

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Graphene oxide sheets fixed over silica particles (SiGO) and their modification functionalized with C18 and endcapped (SiGO-C18ec) have been reported as sorbents for extraction and analytical columns in LC. In this study, a SiGO column was selected as the extraction column and a SiGO-C18ec as the analytical column to study the applicability and limitations of a column-switching system composed exclusively of columns packed with graphene-based sorbents. Pyriproxyfen and abamectin B1a were selected as the analytes, and orange-flavored carbonated soft drinks as the matrix.

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Sample preparation is usually a complex and time-consuming procedure, which can directly affect the quality of the analysis. Recent efforts have been made to establish analytical methods involving minimal sample preparation, automatized and performed online with the analytical techniques. Online Extraction coupled with Liquid Chromatography-Mass Spectrometry (OLE-LC-MS) allows a fully connected extraction, separation, and analysis system.

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Graphene oxide-based LC stationary phases were developed and applied for separating hormones from urine using capillaryLC-MS/MS. Using two analytical approaches - direct injection and column-switching arrangement - it was possible to evaluate the chromatographic parameters and perform tests on the raw biological fluid. Two stationary phases (SPs) were produced, varying the amino silica support particle diameter (Si, 5, and 10 μm).

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Graphene and graphene-derived substances are cutting-edge materials receiving increasing attention in the analytical chemistry field. Graphene oxide sheets bonded to amino silica particles functionalized with octadecyl (C18) groups and endcapped, also known as SiGO-C18ec, have been successfully employed as extraction phases and in analytical columns associated with conventional liquid chromatography (LC). In this work, SiGO-C18ec particles of 3, 5, and 10 µm nominal id were employed to pack capillary LC columns (100 mm long x 0.

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A 25 µm i.d x 1.2 m length PS-DVB porous layer open tubular column (PLOT) was prepared and assessed in the configuration of a nano liquid chromatography coupled to an electron ionization mass spectrometry system (OT-nanoLC-EI-Ms), via the direct insertion of the column outlet into the ionization source.

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Open tubular liquid chromatography (OT-LC) can provide superior chromatographic performance and more favorable mass spectrometry (MS) detection conditions. These features could provide enhanced sensitivity when coupled with electrospray ionization sources (ESI-) and lead to unprecedented detection capabilities if interfaced with a highly structural informative electron ionization (EI) source. In the past, the exploitation of OT columns in liquid chromatography evolved slowly.

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