CIDEPINT   05376
CENTRO DE INVESTIGACIONES EN TECNOLOGIA DE PINTURAS
Unidad Ejecutora - UE
artículos
Título:
New method to sinterize silica frits to produce capillary microcolumns
Autor/es:
KEUNCHKARIAN, S.; LEBED, P. J.; SLIZ, B.; CASTELLS, C. B.; GAGLIARDI, L. G
Revista:
ANALYTICA CHIMICA ACTA
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Amsterdam; Año: 2014 vol. 820 p. 168 - 175
ISSN:
0003-2670
Resumen:
One of the main steps in the manufacture of
robust and efficient packed capillary microcolumns for electro- and capillary
chromatography is the generation of porous devices to retain the packed beds.
Frits based on sintered silica particles have been found to give the best
results in terms of mechanical resistance and efficiency. The conventional
procedure to produce these kinds of frits consists in a radial heating of the
packed material with either a flame or an electrical resistance, but the frits
thus obtained have many drawbacks as a result of the procedure rather than the
silica per se as the base material. In the present work we investigated
a new approach to produce silica-based retaining devices involving the frontal
exposure of a short silica-particle bed packed at the end of a capillary tube.
The capillary is radially insulated and frontally exposed to the heat of a
muffle oven, generating a transfer of heat that is not radial but rather
throughout the capillary axis. This procedure resulted in substantial
advantages: an improved radial homogeneity, a protection of the external
polyimide, and a generation of extremely short (400?600 µm) frits that were
highly permeable and avoided bubble formation.