CA2389726A1 - Analytical devices based on diffusion boundary layer calibration and quantitative sorption - Google Patents
Analytical devices based on diffusion boundary layer calibration and quantitative sorption Download PDFInfo
- Publication number
- CA2389726A1 CA2389726A1 CA 2389726 CA2389726A CA2389726A1 CA 2389726 A1 CA2389726 A1 CA 2389726A1 CA 2389726 CA2389726 CA 2389726 CA 2389726 A CA2389726 A CA 2389726A CA 2389726 A1 CA2389726 A1 CA 2389726A1
- Authority
- CA
- Canada
- Prior art keywords
- coating
- sample
- analytes
- membrane
- interest
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/40—Concentrating samples
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/40—Concentrating samples
- G01N1/405—Concentrating samples by adsorption or absorption
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
- G01N2030/009—Extraction
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Sampling And Sample Adjustment (AREA)
Abstract
This invention relates to a method and apparatus of determining the concentration of analytes in sample using an extraction device whereby the concentration of analytes of interest can be determined from the diffusion coefficient for said analytes. Various designs of the extraction devices are considered including fibres, membranes, coated vessels and stirring mechanisms. To facilitate well-defined boundary layer, agitation means are incorporated in the design of the devices.
Claims (61)
1. A method of determining the concentration of analytes of interest in a sample using a solid phase microextraction device having a surface containing an extraction coating, said method comprising bringing said sample into contact with said coating while highly agitating said sample under controlled conditions to maintain a substantially constant boundary layer between said sample and said coating, limiting a time of contact between said sample and said coating so that all analytes that pass through said boundary layer are adsorbed, terminating said contact and determining the amount of each analyte of interest in said coating and calculating the concentration of the analytes of interest in said sample by using the diffusion coefficient for said analytes and said amount in said coating.
2. A method as claimed in Claim 1 including the step of limiting the time of contact between said sample and said coating to a range of a few seconds to substantially two minutes.
3. A method as claimed in Claim 2 including the step of limiting the time of contact to substantially one minute.
4. A method as claimed in Claim 3 including the step of limiting the time of contact to substantially ten seconds.
5. A method as claimed in Claim 3 including the step of sizing the coating to be much larger than the maximum coating required to adsorb all of the analytes that pass through said boundary layer within the time of contact.
6. A method as claimed in Claim 1 including the step of selecting said surface from the group of a fiber, a tube, an interior surface of a vessel, suspended particles, a stirrer and a stirring bar and a disk.
7. A method as claimed in Claim 6 wherein the surface is a fiber and said method includes the step of highly agitating said sample by vibrating said fiber.
8. A method as claimed in Claim 6 wherein the surface is a tube and the method includes the step of highly agitating said sample by forcing said sample through said tube.
9. A method as claimed in Claim 6 wherein the sample is located in a vessel and the surface is an interior surface of said vessel, said method including the step of highly agitating said sample by vibrating said vessel.
10. A method as claimed in Claim 6 wherein said surface is a surface of said suspended particles, said method comprising highly agitating said sample by vibrating or shaking said vessel.
11. A method as claimed in Claim 6 wherein said vessel contains a stirrer, said stirrer having paddles with said extraction coating located thereon, said method comprising highly agitating said sample by activating said stirrer.
12. A method as claimed in Claim 6 wherein said vessel contains a stirrer, said method comprising highly agitating said sample by activating said stirrer.
13. A method as claimed in Claim 6 wherein a vessel contains a stirring bar, a surface of the stirring bar being the surface that has the extraction coating thereon, said stirring bar having an extraction coating thereon, said method comprising highly agitating said sample by activating said stirring bar.
14. A method as claimed in Claim 6 including a step of controlling the agitation by maintaining said agitation conditions at a substantially constant level.
15. A method as claimed in Claim 1 including the steps of controlling the agitation conditions to vary the degree of agitation, correlating the degree of agitation with the amount of extraction and determining the concentration of analytes of interest by adjusting for the degree of agitation.
16. A method as claimed in Claim 1 including the step of desorbing said analytes from said coating by inserting said coating into an injection port of a suitable analytical instrument.
17. A method as claimed in Claim 2 wherein said sample contains particulates and said method includes the steps of accumulating particulates on said surface and using one of Raman spectroscopy and x-ray flourescence to characterize the accumulated particulates.
18. A method as claimed in Claim 1 including the step of creating a well-defined artificial boundary layer by using a polymeric membrane that covers said surface containing said extraction coating.
19. A method of determining the concentration of analytes of interest in a sample using an extraction device having a membrane, said method comprising bringing said sample into contact with said membrane for a sufficient time to allow microextraction to occur, said membrane having a large surface area so that all analytes that contact said membrane can be adsorbed, limiting the contact time between the sample and the membrane, separating the membrane from the sample, determining the amount of each analyte of interest in said membrane and calculating the concentration of said analytes of interest in said sample using the diffusion coefficient for the analytes and said amount in said membrane.
20. A method as claimed in Claim 19 including the step of highly agitating said sample under controlled conditions.
21. A method as claimed in Claim 20 wherein said membrane has a handle, said method including the step of rolling or folding said membrane about said handle.
22. A method as claimed in Claim 20 including the step of compacting said membrane after adsorption has taken place.
23. A method as claimed in Claim 1 including the step of desorbing analytes from said coating by placing said coating into an injection port of an analytical instrument and carrying out desorption and analysis.
24. A method as claimed in Claim 1 including the steps of choosing the coating to be a mixed phase coating.
25. A method as claimed in Claim 24 including the step of choosing the coating from the group of PDMS/DVB, Carboxen/PDMS and Carbowax/DVB.
26. A method as claimed in Claim 1 including the step of choosing the coating to be a solid, liquid, inorganic or organic coating including molecular imprinted polymers (MIP's), antibodies and polypyrroles.
27. A method as claimed in Claim 1 including the step of choosing the coating to selectively extract analytes of interest from the sample.
28. A method as claimed in Claim 1 including the steps of collecting the analytes in the field using a portable device, sealing the analytes collected and returning to a location that has an analytical instrument, desorbing the analytes collected into the instrument.
29. A method as claimed in Claim 1 including the steps of carrying out extraction for a limited time that is far short of the extraction tune required to reach equilibrium.
30. A method of calibrating a device for determining the concentration of analytes of interest in a sample, said device being an extraction device and having at least one of a surface containing an extraction coating and a membrane therein, said method comprising bringing said sample into contact with at least one of said coating and said membrane while highly agitating said sample under controlled conditions to maintain a substantially constant boundary layer between said sample and at least one of said coating and said membrane, limiting a time of contact between said sample and at least one of said coating and said membrane so that all analytes that have passed through said boundary layer are adsorbed by at least one of said coating and said membrane, terminating said contact and determining the amount of each analyte of interest in at least one of said coating and said membrane, measuring the concentration of analytes of interest in said sample or starting with a known concentration of analytes of interest in a sample, comparing the amount of each analyte of interest in at least one of said coating and said membrane with the known concentration to calibrate the device and calibrating the device based on the diffusion coefficient for the analytes of interest.
31. A method as claimed in any one of Claims 1, 19 or 30 including the step of determining the concentration of analytes of interest in at least one of said coating and said membrane by desorbing said analytes of interest into an analytical instrument.
32. A device for determining the concentration of analytes of interest in a sample, said device comprising a solid phase microextraction device having a surface containing an extraction coating, agitation means to highly agitate the sample under controlled conditions during microextraction, said coating being sized and shaped to fit into an injection port of an analytical instrument.
33. A device as claimed in Claim 32 wherein the surface containing the extraction coating is at least one of a fiber, an interior of a tube, an interior of a vessel, a particle within the sample, a stirrer and a stirring bar.
34. A device as claimed in Claim 32 wherein the means to highly agitate the sample under controlled conditions is at least one of a vibrator, a stirrer, a stirring bar and a flowing sample.
35. A device as claimed in Claim 32 wherein the coating is selective with respect to the analytes of interest.
36. A device as claimed in Claim 32 wherein the coating is a solid, liquid, inorganic or organic coating molecular imprinted polymers (MIP's), antibodies and polypyrroles.
37. A device as claimed in Claim 32 wherein the coating is a mixed phase coating.
38. A device as claimed in Claim 37 wherein the coating is a PDMS/DVB, Carboxen/PDMS or Carbowax/DVB coating.
39. A device for determining the concentration of analytes of interest in a sample, said device comprising a membrane having a large surface area to adsorb all analytes that contact a surface of said membrant in a time allowed for extraction, said membrane being sized and shaped to fit into an injection port of an analytical instrument.
40. A device as claimed in Claim 39 wherein the membrane is attached to a handle.
41. A device as claimed in Claim 40 wherein the membrane has a rectangular shape with a large surface area relative to the analytes of interest that can be potentially adsorbed during the time of exposure.
42. A device as claimed in Claim 41 wherein the membrane can be folded.
43. A device as claimed in Claim 34 wherein the membrane is folded by rolling the membrane around the handle.
44. A device as claimed in Claim 43 wherein there is a sheath into which the rolled up membrane can be inserted and sealed.
45. A device as claimed in Claim 44wherein the device is portable.
46. A device as claimed in Claim 34 wherein the surface is a fiber connected to a holder, said fiber being extendable and retractable, into and out of said holder respectively.
47. A device as claimed in Claim 46 wherein holder is a syringe like device having a needle, barrel and plunger, said fiber being located within the needle when the fiber is retracted by moving said plunger, said fiber extending beyond the needle when said plunger is depressed.
48. A device as claimed in Claim 34 wherein the surface is a plurality of fibers connected to a holder, said fibers being extendable and retractable into and out of said holder respectively.
49. A device for determining the concentration of analytes of interest in a sample, said device comprising a solid phase microextraction device having an extraction coating with a large surface area to volume configuration, and agitation means to highly agitate the sample under controlled conditions during microextraction, said extraction coating being sized and shaped to fit into an injection port of an analytical instrument.
50. A device as claimed in Claim 49 wherein said extraction coating is selected from the group consisting of a membrane, a surface of a plurality of fibers, and a coating present on a plurality of fibers, wherein when said extraction coating is either a surface of a plurality of fibers or coating present on a plurality of fibers, said device may optionally comprise a holder, said fibers being extendable into and retractable out of said holder.
51. A device as claimed in Claim 49 for determining the concentration of analytes of interest in a sample, said extraction coating comprising a membrane having a large surface area to adsorb all analytes that contact said membrane in a time allowed for extraction, said membrane being sized and shaped to fit into an injection port of an analytical instrument, wherein the membrane is optionally attached to a handle, and optionally wherein the membrane is foldable, for example by rolling the membrane around the handle.
52. A device for determining the concentration of analytes of interest in a sample, said device comprising a solid phase microextraction device having a surface containing an extraction coating, and agitation means to highly agitate the sample under controlled conditions during microextraction, said coating being sized and shaped to fit into an injection port of an analytical instrument, said microextraction device being configured adjacent said agitation means to allow determination of concentration of analytes in a sample of interest on site, and optionally wherein the device for determining the concentration of analytes of interest is portable.
53. A device as claimed in Claim 52 wherein the surface containing the extraction coating is at least one of a fiber, a plurality of fibers, an interior of a tube, an interior of a vessel, a particle within the sample, a stirrer and a stirring bar, and wherein when the surface is a fiber, said fiber is optionally extendable into and retractable out of a holder, said holder optionally comprising a syringe having a needle, barrel and plunger, said fiber being located within the needle when the fiber is retracted by withdrawing said plunger, and said fiber being extended beyond the needle by depressing said plunger, and wherein the means to highly agitate the sample under controlled conditions may optionally be at least one of a vibrator, a stirrer, a stirring bar and a flowing sample.
54. A device as claimed in Claim 50 or Claim 52 wherein the coating is selective with respect to the analytes of interest, and may comprise a solid, liquid, inorganic or organic coating, for example a mixed phase coating such as PDMS/DVB, Carboxen/PDMS or Carbowax/DVB coating, said coating optionally comprising molecular imprinted polymers (MIPs), antibodies or polypyrroles.
55. A method of determining the concentration of analytes of interest in a sample using a solid phase microextraction device having a surface containing an extraction coating, said method comprising the steps of:
bringing said sample into contact with said coating while highly agitating said sample under controlled conditions to maintain a substantially constant boundary layer between said sample and said coating;
limiting a time of contact between said sample and said coating so that all analytes that pass through said boundary layer are adsorbed;
terminating said contact;
determining the amount of each analyte of interest in said coating; and calculating the concentration of the analytes of interest in said sample by using the diffusion coefficient for said analytes and said amount in said coating.
bringing said sample into contact with said coating while highly agitating said sample under controlled conditions to maintain a substantially constant boundary layer between said sample and said coating;
limiting a time of contact between said sample and said coating so that all analytes that pass through said boundary layer are adsorbed;
terminating said contact;
determining the amount of each analyte of interest in said coating; and calculating the concentration of the analytes of interest in said sample by using the diffusion coefficient for said analytes and said amount in said coating.
56. A method as claimed in Claim 55 including one or more of the following steps:
(i) limiting the time of contact between said sample and said coating to a range of a few seconds to substantially several minutes, for example substantially two minutes, substantially one minute, or substantially ten seconds;
(ii) sizing the coating to be much larger than the maximum coating required to adsorb all of the analytes that pass through said boundary layer within the time of contact;
(iii) selecting said surface from the group consisting of a fiber, a plurality of fibers, a tube, an interior surface of a vessel, suspended particles, a stirrer and a stirring bar, and a disk; and (iv) controlling agitation by maintaining agitation conditions at a substantially constant level;
(v) controlling agitation conditions to vary the degree of agitation, correlating the degree of agitation with the amount of extraction, and determining the concentration of analytes of interest by adjusting for the degree of agitation;
(vi) creating a well-defined artificial boundary layer by using a polymeric membrane that covers said surface containing said extraction coating;
(vii) desorbing analytes from said coating by inserting said coating into an injection port of a suitable analytical instrument;
(viii) desorbing analytes from said coating by placing said coating into an injection port of an analytical instrument and carrying out desorption and analysis; and (ix) choosing the coating to selectively extract analytes of interest from the sample.
(i) limiting the time of contact between said sample and said coating to a range of a few seconds to substantially several minutes, for example substantially two minutes, substantially one minute, or substantially ten seconds;
(ii) sizing the coating to be much larger than the maximum coating required to adsorb all of the analytes that pass through said boundary layer within the time of contact;
(iii) selecting said surface from the group consisting of a fiber, a plurality of fibers, a tube, an interior surface of a vessel, suspended particles, a stirrer and a stirring bar, and a disk; and (iv) controlling agitation by maintaining agitation conditions at a substantially constant level;
(v) controlling agitation conditions to vary the degree of agitation, correlating the degree of agitation with the amount of extraction, and determining the concentration of analytes of interest by adjusting for the degree of agitation;
(vi) creating a well-defined artificial boundary layer by using a polymeric membrane that covers said surface containing said extraction coating;
(vii) desorbing analytes from said coating by inserting said coating into an injection port of a suitable analytical instrument;
(viii) desorbing analytes from said coating by placing said coating into an injection port of an analytical instrument and carrying out desorption and analysis; and (ix) choosing the coating to selectively extract analytes of interest from the sample.
57. A method as claimed in Claim 55 or 56 wherein the surface is selected from one of the following:
(a) a fiber, wherein the method includes the step of highly agitating said sample by vibrating said fiber;
(b) a tube, wherein the method includes the step of highly agitating said sample by forcing said sample through said tube;
(c) an interior surface of a vessel in which said sample is located, wherein the method includes the step of highly agitating said sample by vibrating said vessel;
(d) suspended particles, said method comprising highly agitating said sample by vibrating or shaking said suspended particles;
(e) a stirrer, said method comprising highly agitating said sample by activating said stirrer;
(f) a stirrer having paddles with said extraction coating located on said paddles, said method comprising highly agitating said sample by activating said stirrer;
and (g) a stirring bar, a portion of the stirring bar having the extraction coating located thereon, said method comprising highly agitating said sample by activating said stirring bar.
(a) a fiber, wherein the method includes the step of highly agitating said sample by vibrating said fiber;
(b) a tube, wherein the method includes the step of highly agitating said sample by forcing said sample through said tube;
(c) an interior surface of a vessel in which said sample is located, wherein the method includes the step of highly agitating said sample by vibrating said vessel;
(d) suspended particles, said method comprising highly agitating said sample by vibrating or shaking said suspended particles;
(e) a stirrer, said method comprising highly agitating said sample by activating said stirrer;
(f) a stirrer having paddles with said extraction coating located on said paddles, said method comprising highly agitating said sample by activating said stirrer;
and (g) a stirring bar, a portion of the stirring bar having the extraction coating located thereon, said method comprising highly agitating said sample by activating said stirring bar.
58. A method as claimed in any one of Claims 55 to 57 including the step of choosing the coating to be a solid, liquid, inorganic or organic coating comprising molecular imprinted polymers (MIPs), antibodies or polypyrroles, and optionally a mixed phase coating, for example PDMS/DVB, Carboxen/PDMS and Carbowax/DVB.
59. A method of determining the concentration of analytes of interest in a sample using an extraction device having a membrane, said method comprising the steps of:
bringing said sample into contact with said membrane for a sufficient time to allow microextraction to occur, optionally while highly agitating said sample under controlled conditions, said membrane having a large surface area so that all analytes that contact said membrane can be adsorbed;
limiting the contact time between the sample and the membrane;
separating the membrane from the sample, and optionally compacting said membrane after adsorption has taken place;
determining the amount of each analyte of interest in said membrane; and calculating the concentration of said analytes of interest in said sample using the diffusion coefficient for the analytes and said amount in said membrane.
bringing said sample into contact with said membrane for a sufficient time to allow microextraction to occur, optionally while highly agitating said sample under controlled conditions, said membrane having a large surface area so that all analytes that contact said membrane can be adsorbed;
limiting the contact time between the sample and the membrane;
separating the membrane from the sample, and optionally compacting said membrane after adsorption has taken place;
determining the amount of each analyte of interest in said membrane; and calculating the concentration of said analytes of interest in said sample using the diffusion coefficient for the analytes and said amount in said membrane.
60. A method as claimed in Claim 55 or Claim 59 including the steps of:
collecting the analytes in the field using a portable device;
sealing the analyzes collected;
returning to a location that has an analytical instrument; and desorbing the analytes collected into the instrument.
collecting the analytes in the field using a portable device;
sealing the analyzes collected;
returning to a location that has an analytical instrument; and desorbing the analytes collected into the instrument.
61. A method of calibrating a device for determining the concentration of analytes of interest in a sample, said device being an extraction device and having at least one of a surface containing an extraction coating and a membrane therein, said method comprising the steps of:
bringing said sample into contact with at least one of said coating and said membrane while highly agitating said sample under controlled conditions to maintain a substantially constant boundary layer between said sample and at least one of said coating and said membrane;
limiting a time of contact between said sample and at least one of said coating and said membrane so that all analytes that have passed through said boundary layer are adsorbed by at least one of said coating and said membrane;
terminating said contact;
determining the amount of each analyte of interest in at least one of said coating and said membrane, optionally by desorbing said analytes of interest into an analytical instrument;
measuring the concentration of analytes of interest in said sample or starting with a known concentration of analytes of interest in a sample;
comparing the amount of each analyte of interest in at least one of said coating and said membrane with the known concentration to calibrate the device; and calibrating the device based on the diffusion coefficient for the analytes of interest.
bringing said sample into contact with at least one of said coating and said membrane while highly agitating said sample under controlled conditions to maintain a substantially constant boundary layer between said sample and at least one of said coating and said membrane;
limiting a time of contact between said sample and at least one of said coating and said membrane so that all analytes that have passed through said boundary layer are adsorbed by at least one of said coating and said membrane;
terminating said contact;
determining the amount of each analyte of interest in at least one of said coating and said membrane, optionally by desorbing said analytes of interest into an analytical instrument;
measuring the concentration of analytes of interest in said sample or starting with a known concentration of analytes of interest in a sample;
comparing the amount of each analyte of interest in at least one of said coating and said membrane with the known concentration to calibrate the device; and calibrating the device based on the diffusion coefficient for the analytes of interest.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA2389726A CA2389726C (en) | 2002-06-27 | 2002-06-27 | Analytical devices based on diffusion boundary layer calibration and quantitative sorption |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA2389726A CA2389726C (en) | 2002-06-27 | 2002-06-27 | Analytical devices based on diffusion boundary layer calibration and quantitative sorption |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2389726A1 true CA2389726A1 (en) | 2003-12-27 |
| CA2389726C CA2389726C (en) | 2010-05-11 |
Family
ID=30449888
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2389726A Expired - Lifetime CA2389726C (en) | 2002-06-27 | 2002-06-27 | Analytical devices based on diffusion boundary layer calibration and quantitative sorption |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2389726C (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113008739A (en) * | 2021-03-23 | 2021-06-22 | 中国石油大学(华东) | Method for determining gas diffusion coefficient under heavy oil thermal recovery condition |
-
2002
- 2002-06-27 CA CA2389726A patent/CA2389726C/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113008739A (en) * | 2021-03-23 | 2021-06-22 | 中国石油大学(华东) | Method for determining gas diffusion coefficient under heavy oil thermal recovery condition |
Also Published As
| Publication number | Publication date |
|---|---|
| CA2389726C (en) | 2010-05-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8192692B2 (en) | Coated chromatograph injection port liner for performing surface sorbent | |
| Olcer et al. | Thin film microextraction: Towards faster and more sensitive microextraction | |
| Lord et al. | Evolution of solid-phase microextraction technology | |
| Cui et al. | Methods to assess bioavailability of hydrophobic organic contaminants: Principles, operations, and limitations | |
| de Koning et al. | Modern methods of sample preparation for GC analysis | |
| Pawliszyn | Solid phase microextraction: theory and practice | |
| EP1039288B1 (en) | Method for solid phase micro-extraction, analysis and collector therefor | |
| Shaw et al. | Uptake and release of polar compounds in SDB-RPS Empore™ disks; implications for their use as passive samplers | |
| US6815216B2 (en) | Method for solid-phase microextraction and analysis, and a collector for this method | |
| Djozan et al. | Preparation and evaluation of solid-phase microextraction fibers based on monolithic molecularly imprinted polymers for selective extraction of diacetylmorphine and analogous compounds | |
| Sander et al. | Determination of column selectivity toward polycyclic aromatic hydrocarbons | |
| US7259019B2 (en) | Multiple sampling device and method for investigating biological systems | |
| US20020178797A1 (en) | Analytical devices based on diffusion boundary layer calibration and quantitative sorption | |
| WO2005050168A3 (en) | Sample collection cup with integrated sample analysis system | |
| WO2003034038A3 (en) | Flow control metering system and method for controlling filtration of liquid-based specimens | |
| US6063038A (en) | Devices and methods for collecting fecal antigen specimens | |
| US6511852B1 (en) | Apparatus for collecting a volatile composition of matter releasably bonded to a pliable porous substrate and process for using said apparatus | |
| US6941825B2 (en) | Analytical devices based on diffusion boundary layer calibration and quantitative sorption | |
| Pawliszyn | Development of SPME devices and coatings | |
| US20040191537A1 (en) | Restricted access material for spme | |
| Ramezani et al. | Dendrimer grafted nanoporous silica fibers for headspace solid phase microextraction coupled to gas chromatography determination of solvent residues in edible oil | |
| CA2389726A1 (en) | Analytical devices based on diffusion boundary layer calibration and quantitative sorption | |
| Kareem et al. | Determination of methamphetamine drug by GC-MS based on molecularly imprinted solid-phase used meth acrylic acid and acryl amide as functional monomers | |
| RU2324173C1 (en) | Method of reception of calibration mixes of volatile components and device for its realisation | |
| JP3590836B2 (en) | Preparation of oil sample for X-ray fluorescence analysis |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKEX | Expiry |
Effective date: 20220627 |