Nanoporous substrates used in a method for separating biological samples

摘要

Disclosed is a method of fractionating or separating very low molecular weight components from a fluid sample, said method comprising the steps of: (a) providing a fluid sample comprising a first component consisting of molecules having a molecular weight no higher than 20 kilodaltons and a second component; (b) providing a substrate comprising a solid-phase silica-based nanoporous material having a pore size that allows the passage of molecules having a molecular weight equal to or below a molecular cut-off weight and functions as a molecular sieve by retaining substantially all molecules having a molecular weight equal to or below the molecular cut-off weight and excluding substantially all molecules having a molecular weight above the molecular cut-off weight; and (c) exposing the substrate to the sample, such that the first component penetrates the solid-phase silica-based nanoporous material while the remainder of the fluid sample does not penetrate the nanoporous material. Also disclosed is a kit comprising means for collecting the components from a sample. Also disclosed is a probe that comprises a silicon-based nanoporous material configured to be inserted into a mass spectrometer. The disclosed method, kit and probe are all directed toward analytical devices and systems utilising nanoporous materials.