Modified cyclodextrins for fast and sensitive chiral‐capillary electrophoresis‐mass spectrometry

Abstract

In this work, three modified CDs (mCDs), namely 6-deoxy-6-[1-(2-amino)ethylamino]-beta-CD, 6-deoxy-6-[N-(2-methylamino)pyridine)]-beta-CD and 3-monodeoxy-3-monoamino-beta-CD, are investigated as chiral selectors for CE with LIF (CE-LIF) and CE-TOF-MS. The potential of these three mCDs as chiral selectors in CE was also compared with the unmodified beta-CD and gamma-CD. A group of ten different D- and L-amino acids derivatized with FITC was selected as case-study for CE-LIF and CE-MS comparison. The analyte group includes negatively (D/L-Glu and D/L-Asp), neutral (D/L-Ala and D/L-Asn) and positively (D/L-Arg) charged amino acids. Chiral separation conditions compatible with CE-TOF-MS could be achieved based on the figures of merit obtained by CE-LIF using the different CDs. Interestingly, LOD values obtained by chiral CE-TOF-MS were in the nM range comparable or only slightly worse to those obtained by CE-LIF. Moreover, the time of analysis using mCDs was reduced more than 30% compared with the non-chiral conditions (19.2 versus 28.4 min, respectively), with resolution and efficiency values as high as 5.15 and 843 000 plates/m, respectively. The usefulness of this chiral CE-TOF-MS method was corroborated through the detection of the main D- and L-amino acids found in different real samples including transgenic versus wild soy and vinegar.

Profiling of Genetically Modified Organisms Using Omics Technologies

“…Interestingly, 4-hydroxy-l-threonine seemed to disappear in the transgenic soybean compared to its parental non-transgenic line. In a separate report, herbicide-resistant transgenic soybean was characterized by Giuffrida et al using a novel chiral CE-ESI-TOF-MS method [94]. In that research, the obtained D/L-amino acid profiles were very similar for conventional and GM soybean.…”

Mass spectrometry detection as an innovative and advantageous tool in ligand exchange capillary electrophoresis

“…Detection by electrospray-mass spectrometry (ESI/MS) is now a well-established technique in CE [25][26][27] and, recently [28], some of us carried out a study, simultaneously separating different enantiomeric pairs of fluorescent amino acids derivatives in CE with laser-induced fluorescence (LIF) detection and CE-TOF-MS, by using SID CD as a selector. The investigation showed that MS can be conveniently used as alternative detection technique, and that the usual thinking that the presence of CDs in the background electrolyte (BGE) prevents the use of MS detection has exceptions.…”

Caracterização eletroforética e espectrométrica de extratos de Cinchona de uso fitoterápico e cosmético

“…em relação a cromatografia liquida é seu limite de detecção relativamente pobre em relação à cromatografia liquida (Giuffrida et al, 2009). …”

“…Deste modo, a CE-MS quiral permite combinar a velocidade de separação, poder de resolução elevado, mínimo de amostra e reagentes são consumidos na CE e com as informações fornecidas pelo MS (Giuffrida et al, 2009). fornecida por este tipo de montagem é fortemente dependente da composição qualitativa e quantitativa do eletrólito utilizado para separação, assim como do líquido auxiliar.…”

“…fornecida por este tipo de montagem é fortemente dependente da composição qualitativa e quantitativa do eletrólito utilizado para separação, assim como do líquido auxiliar. Outros fatores como a pressão do gás nebulizador, o fluxo do líquido auxiliar bem como a temperatura da interface também são fatores que influenciam de forma decisiva os resultados no que se refere a relação sinal/ruído (Moraes e Lago, 2003;Simionato et al, 2008;Giuffrida et al, 2009).…”