Sampling from a magnetic induced heterogenous system
In one aspect, a method of extracting a target analyte from a sample for introduction into a mass spectrometer is disclosed, which includes mixing the sample with a paramagnetic medium to form a mixture, subjecting the mixture to a magnetic field gradient to form a non-homogenous distribution of at least one of the analyte and at least one interfering component of the sample, if any, thereby enhancing a concentration of the target analyte within a spatial location of said mixture, extracting at least a portion of the target analyte from that spatial location, and introducing at least a portion of the extracted target analyte into said mass spectrometer.
1 . A method of extracting a target analyte from a sample for introduction into a mass spectrometer, comprising:
mixing the sample, which includes the target analyte and at least one interfering component, with a paramagnetic medium to form a mixture of the sample and the paramagnetic medium,
subjecting the mixture to a magnetic field gradient to form a non-homogenous distribution of at least one of said target analyte and the at least one interfering component thereby enhancing a concentration of said target analyte within a spatial location of said mixture,
extracting at least a portion of said target analyte from said spatial location, and
introducing at least a portion of said extracted target analyte into said mass spectrometer.
2 . The method of claim 1 , wherein the enhancing the concentration of said analyte within said spatial location results in enhancing a concentration ratio of said analyte relative to the at least one interfering component in said spatial location.
3 . The method of claim 2 , wherein said magnetic field gradient causes an increase in concentration ratio of said interfering component and said analyte in another spatial location of said mixture.
4 . The method of claim 3 , further comprising discarding at least a portion of said interfering component from said another spatial location prior to the step of extracting said target analyte.
5 . The method of claim 1 , wherein said magnetic field gradient is configured to cause attraction of the target analyte and the interfering component having a different density than the target analyte to different locations within said paramagnetic medium.
6 . The method of claim 1 , wherein said sample is disposed in a sample holder and the sample holder is maintained in a substantially vertical orientation such that a balance of gravity, buoyancy force and said magnetic field gradient results in said analyte being stably maintained within said spatial location.
7 . The method of claim 6 , wherein said analyte has a density greater than that of the paramagnetic medium and a balance of the buoyancy force and gravity pushes the analyte toward a bottom end of said sample holder.
8 . The method of claim 7 , further comprising extracting at least a portion of said analyte from the bottom end of the sample holder.
9 . The method of claim 8 , wherein the step of extracting at least a portion of said analyte from the bottom end of the sample holder comprises utilizing iDOT technology or utilizing inkjet sampling.
10 . The method of claim 6 , wherein said analyte has a density less than that of the paramagnetic medium such that a balance of the buoyancy force and gravity pushes the analyte toward a top end of said sample holder.
11 . The method of claim 10 , further comprising extracting at least a portion of the analyte from the top of the sample holder.
12 . The method of claim 11 , wherein the step of extracting at least a portion of the analyte from the top of the sample holder comprises utilizing acoustic ejection.
13 . The method of claim 1 , wherein said magnetic field gradient is generated by at least two magnets one of which is positioned in vicinity of a top end of said sample holder and the other is positioned in vicinity of a bottom end thereof such that same poles of the two magnets substantially face one another.
14 . The method of claim 1 , further comprising, prior to mixing the sample with the paramagnetic medium, introducing a plurality of diamagnetic particles functionalized to capture said target analyte into said sample so as to capture at least a portion of said target analyte by said functionalized diamagnetic particles.
15 . The method of claim 14 , wherein said magnetic field gradient causes said diamagnetic particles to be attracted toward said spatial location.
16 . The method of claim 14 , wherein said diamagnetic particles comprise any of silicon, PMMA, polystyrene, Teflon or silica.
17 . The method of claim 1 , wherein said paramagnetic medium comprises an aqueous solution of one or paramagnetic salts, or wherein said analyte comprises a plurality of droplets that are immiscible in said paramagnetic medium.
18 . The method of claim 15 , wherein said paramagnetic salts comprise any of MnCb and GdCb.
19 . The method of claim 1 , wherein the step of introducing at least a portion of said extracted target analyte to said mass spectrometer comprises directing said extracted analyte to an inlet port of the mass spectrometer.
20 . The method of claim 18 , wherein said inlet port of the mass spectrometer is an open port interface (OPI).