High density cast-in-place sample preparation card

Abstract

A card or insert having a plurality of recesses for a sample preparation device, the card containing cast-in-place composite and/or non-filled structures which are useful as sorptive or reactive media or for size-based separations. Any particular card size or configuration can be used, and the inclusion of a large amount of adsorptive particles in polymer is achieved while still maintaining the membrane three dimensional structure. In a first preferred embodiment, the composite structures comprise particles entrapped within a porous polymeric substrate, and are cast in-place into a plurality of recesses in an insert for a multi-well sample preparation device, thereby providing an effective platform for high throughput micromass handling. With the appropriate selection of particle chemistry, virtually any separation or purification operation can be conducted in multiplicity, including selective bind/elute chromatography, operations, on sample mass loads less than 1 microgram in volumes of a few microliters, as well as larger mass loads and volumes. Manufacturing flexibility and high throughput is achieved. The card can be configured for direct analysis of bound sample without elution.

1 . A method of direct spectrometric analysis of a sample, comprising:
 (a) providing a housing having a first surface and a second surface spaced from said first surface, said housing having one or more apertures formed between and communicating with said first and second surfaces, each of said one or more apertures containing a structure comprising a plurality of sorptive particles entrapped in a porous matrix;   (b) introducing a sample onto said structure;   (c) causing a first portion of said sample to pass through said structure and out of said housing and a second portion of said sample to bind to said structure; and   (d) analyzing said second portion of said sample.   
   
   
       2 . The method of  claim 1 , further comprising, after step (c), coating said structure with a MALDI time-of-flight matrix, and positioning said housing in a spectrometer for analysis of said second portion of said sample without eluting said second portion from said structure. 
   
   
       3 . The method of  claim 1 , wherein said analysis is carried out with a MALDI time-of-flight mass spectrometer.