Publications by authors named "Elisabetta Gonella"

Surface-activated chemical ionization (SACI) was employed for the analysis of cocaine and its metabolite, benzoylecgonine, extracted from hair. Following decontamination and acid hydrolysis procedures on the hair sample, the sample solution was diluted (1:10) and directly analyzed by liquid chromatography/surface-activated chemical ionization multiple collisional stage single reaction monitoring mass spectrometry (LC/SACI-MS(3)-SRM) without solid-phase extraction (SPE) pre-purification and concentration procedures. To increase the selectivity of the method, MS(3) was chosen instead of the less selective MS/MS.

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The new atmospheric pressure chemical ionization source, named surface-activated chemical ionization (SACI), has been used in conjunction with high-flow gradient chromatography to reduce the matrix effect. This high-flow gradient chromatography approach avoids the co-elution of analyte and biological matrix compounds that leads to a reduction in quantitation errors due to matrix effect. However, this approach cannot be employed with the classical electrospray ionization (ESI) source that usually works at low eluent flow (< 300 microL/min).

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The new ionization method, called surface-activated chemical ionization (SACI), was employed for the analysis of fives drugs (morphine, codeine, 6-monoacetylmorphine (6-MAM), benzoylecgonine and cocaine) by ion trap mass spectrometry. The results so obtained have been compared with those achieved by using atmospheric pressure chemical ionization (APCI), no-discharge-APCI and electrospray ionization (ESI) clearly showing that SACI is the most sensible one mainly due to the high ionization efficiency and the lower chemical noise. The performance of SACI in terms of sensitivity and linearity was compared with the sensitivity and linearity obtained using APCI, no-discharge-APCI and ESI, showing that the new SACI approach gives rise to the best results.

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Alterations of arginine plasma levels are involved in several disorders of amino acid metabolism such as hurtnup, argininosuccinic aciduria, histidinemia, citrullinuria, and cystinuria. In this work a new liquid ionization source, surface-activated chemical ionization (SACI), has been used to analyze arginine in human and rat plasma samples. Arginine was extracted and diluted ten times through protein precipitation.

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A new ionization method, named surface-activated chemical ionization (SACI), was employed for the analysis of five amphetamines (3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyethylamphetamine (MDE), amphetamine and methamphetamine) by ion trap mass spectrometry. The results so obtained have been compared with those achieved by using atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI) using the same instrument, clearly showing that SACI is the most sensitive of the three. The limit of detection and linearity range for SACI were compared with those obtained using APCI and ESI, showing that the new SACI approach provides the best results for both criteria.

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