Integrated sample preparation, separation and introduction microdevice for inductively coupled plasma mass spectrometry

In an apparatus for performing mass analysis of a fluid sample wherein the fluid sample is ionized in an ionization chamber, the improvement comprising providing a microdevice for introducing the fluid sample into the ionization chamber, the microdevice comprising:

• a substrate having a first and second opposing surfaces, the substrate having a microchannel formed in the first surface;
• a cover plate arranged over the first surface, the cover plate in combination with the microchannel defining a conduit for conveying the sample;
• a sample inlet port in fluid communication with the conduit, wherein the sample inlet port allows the fluid sample from an external source to be conveyed in a defined sample flow path that travels, in order, through the sample inlet port, the conduit and a sample outlet port and into the ionization chamber;
• and
• a nebulizing means for nebulizing the fluid sample in a nebulizing region adjacent to the sample outlet port,
• wherein the substrate, the cover plate, and nebulizing means are each comprised of a polymeric material that is chemically inert and physically stable to the fluid sample, and the nebulizing means represents an integrated portion of the microdevice.

A method for analyzing a fluid sample in an inductively coupled plasma mass spectrometer, comprising the steps of:

• (a) providing a microdevice comprising:
• a substrate having a first and second opposing surfaces, the substrate having a microchannel formed in the first surface;
• a cover plate arranged over the first surface, the cover plate in combination with the microchannel defining a conduit for conveying the sample;
• and
• a sample inlet port in fluid communication with the conduit, wherein the sample inlet port allows the fluid sample from an external source to be conveyed in a defined sample flow path that travels, in order, through the sample inlet port, the conduit and a sample outlet port and into the ionization chamber,
• wherein the substrate, the cover plate, and nebulizing means are each comprised of a polymeric material that is chemically inert and physically stable to the fluid sample, and the nebulizing means represents an integrated portion of the microdevice;
• (b) injecting the fluid sample into the sample inlet port;
• (c) conveying the fluid in the defined sample flow path to the ionization chamber in a nebulized form;
• and
• (d) analyzing the fluid sample.