Sample dispenser including an internal standard and methods of use thereof
The invention generally relates to a sample dispenser including an internal standard and methods of use thereof.
1. A method for analyzing a sample comprising:
preparing a mixture of a sample with a controlled amount of an internal standard;
contacting the mixture to a porous substrate that tapers to at least one tip, wherein the porous material is kept separate from a flow of solvent and the probe operates without pneumatic assistance;
applying a high voltage to the porous material such that an electric field is generated at a tip of the material so as to generate ions of an analyte and ions of the internal standard that are expelled from the porous material; and
analyzing the expelled ions.
2. The method according to claim 1 , further comprising applying a solvent to the porous substrate.
3. The method according to claim 1 , wherein the solvent assists in transport of the sample through the porous substrate.
4. The method according to claim 2 , wherein the solvent minimizes salt and matrix effects.
5. The method according to claim 1 , wherein analyzing comprises providing a mass analyzer to generate a mass spectrum of analytes in the sample.
6. The method according to claim 1 , wherein the sample is a biological sample.
7. The method according to claim 6 , wherein the biological sample is a blood sample or a urine sample.
8. The method according to claim 1 , further comprising quantifying a target analyte in the sample.
9. The method according to claim 1 , wherein the preparing step comprises introducing the sample to a capillary on which walls of the capillary comprise the internal standard.
10. The method according to claim 9 , wherein a volume of the capillary regulates a volume of the sample and a volume of the internal standard that comprise the mixture.
11. The method according to claim 9 , wherein the sample comprises a volume of about 1 μL or less.