Coupling of capillary electrophoresis (CE) with mass spectrometry (MS) represents a powerful combination for performing rapid, efficient, and sensitive analysis of a variety of compounds. Here we describe a construction, operation, and application of a microfabricated liquid junction CE-MS interface. The interface is designed as a microfabricated unit with an integrated liquid junction and electrospray tip made from polyimide, which is positioned in a plastic connection block securing the separation CE capillary and attachable to the CE instrument. The application was demonstrated by CE-MS analysis of dextran oligomers labeled by (2-aminoethyl)trimethylammonium (AETMA) salt.

• MeSH
• elektroforéza kapilární * metody   MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací * MeSH
• hmotnostní spektrometrie metody   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

One of the challenging instrumental aspects in coupling an automated CE instrument with ESI mass spectrometry (CE-MS) is finding the balance between the stability, reproducibility and sensitivity of the analysis and compatibility with the standard CE instrumentation. Here, we present a development of a new liquid junction based electrospray interface for automated CE-MS, with a focus on the technical design followed by computer modeling of transport conditions as well as characterization of basic performance of the interface. This hybrid arrangement designed as a microfabricated unit attachable to the automated CE instrument allows using of a wide range of separation capillaries with respect to their diameter, length or internal coating (e.g., for suppressed electroosmotic flow). Different compositions of the ESI liquid and background electrolyte solutions can be used if needed. The microfabricated part, prepared by laser machining from polyimide, includes a self-aligning liquid junction, a short transport channel, and a pointed sprayer for the electrospray ionization. This microfabricated part is positioned in a plastic connection block securing the separation capillary and flushing ports. Transport conditions were modelled using computer simulation and the real life performance of the interface was compared to that of a commercial sheath liquid interface. The basic performance of the interface was demonstrated by separations of peptides, proteins, and oligosaccharides.

• MeSH
• chemické modely MeSH
• elektroforéza kapilární přístrojové vybavení   MeSH
• hmotnostní spektrometrie přístrojové vybavení   MeSH
• laboratorní automatizace MeSH
• mikrofluidní analytické techniky přístrojové vybavení   metody   MeSH
• proteiny analýza   izolace a purifikace   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

We report a construction of a self-aligning subatmospheric hybrid liquid junction electrospray interface for CE eliminating the need for manual adjustment by guiding the capillaries in a microfabricated liquid junction glass chip at a defined angle. Both the ESI and separation capillaries are inserted into the microfabricated part until their ends touch. The distance between the capillary openings is defined by the angle between the capillaries. The microfabricated part contains channels for placement of the capillaries and connection of the external electrode reservoirs. It was fabricated using standard photolithographic/wet chemical etching techniques followed by thermal bonding. The liquid junction is connected to a subatmospheric electrospray chamber inducing the flow inside the ESI needle and helping the ion transport via aerodynamic focusing.

• MeSH
• design vybavení MeSH
• dextrany MeSH
• elektroforéza kapilární přístrojové vybavení   MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací přístrojové vybavení   MeSH
• mikrofluidní analytické techniky přístrojové vybavení   MeSH
• peptidy MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH