title: Pressurized nano-liquid-junction interface for coupling capillary electrochromatography and nano-liquid chromatography with mass spectrometry.
abstract: A new nano-liquid-junction interface for coupling both capillary electrochromatography (CEC) or nano-liquid chromatography (nano-LC) with mass spectrometry (MS) was studied. The interface was a small T piece of polymeric material where capillary column and tip capillary were positioned at 180° while the third exit (at 90°) was occupied by a capillary delivering a liquid-assisting spray ionization for CEC experiments or by the electrode for the high voltage spray for nano-LC. Experiments were carried out analyzing mixtures of some organophosphorus pesticides (OPPs) or anti-inflammatory and related acidic drugs with MS detection in positive or negative ion mode, respectively. Analyzed OPPs compounds were baseline resolved utilizing the novel interface in both nano-LC and CEC obtaining good sensitivity and repeatability. For CEC-MS, the limits of detection ranged between 0.03 and 6.80 μg/mL and the intra-day repeatability was RSD <3.8% and <13% for the retention times and peak areas, respectively. The interface was easy to handle and good reproducibility, between 2.5 and 3.5% for the retention time and <10% for the efficiencies, was obtained when the interface was installed by two different analysts. Furthermore, it could be used for both CEC and nano-LC.
authors.affiliation: Institute of Chemical Methodologies, Italian National Council of Research, Area della Ricerca di Roma I, Via Salaria km 29,300 - 00015 Monterotondo (Rome), Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: D'Orazio
authors.forename: Salvatore
authors.initials: S
authors.lastname: Fanali
mesh_terms: D053801:Capillary Electrochromatography / Q000295:instrumentation* / Q000379:methods; D057230:Limit of Detection; D013058:Mass Spectrometry / Q000295:instrumentation* / Q000379:methods; D036103:Nanotechnology / Q000295:instrumentation*; D009943:Organophosphorus Compounds / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification; D010575:Pesticides / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification; D004364:Pharmaceutical Preparations / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification; D015203:Reproducibility of Results
chemical_list: D009943:Organophosphorus Compounds; D010575:Pesticides; D004364:Pharmaceutical Preparations
keywords: CEC-MS; Capillary electrochromatography; MS interface; Nano-liquid chromatography; Nano-liquid–junction interface; Organophosphorus pesticides