Multiaperture sample positioning and analysis system

• US 7,244,349 B2
• Filed: 08/27/2002
• Issued: 07/17/2007
• Est. Priority Date: 12/17/1997
• Status: Expired due to Fees

• Current Assignee: Molecular Devices, Ecole polytechnique fãdãrale de lausanne epfl (Schweizerische Eidgenossenschaft)
• Original Assignee: Molecular Devices
• Inventors: Schmidt, Christian, Vogel, Horst
• Primary Examiner(s): Olsen; Kaj K.
• Application Number:
  US10/229,863
• Publication Number:
  US 20030098248A1
• Time in Patent Office: 1,785 Days
• Field of Search: 204/403.01, 204/403.03, 204/416, 205/777.5, 205/778, 435/4, 435/173.4, 435/173.6, 435/287.1, 435/288.4, 435/288.7
• US Class Current: 205/777.5
• CPC Class Codes: B01L 3/5085 for multiple samples, e.g. microtitration plates
• CPC Class Codes: G01N 33/48728 Investigating individual cells, e.g. by patch clamp, voltage clamp investigating individual particles in general G01N15/10

Abstract

Systems for positioning and/or analyzing samples such as cells, vesicles, cellular organelles, and fragments, derivatives, and mixtures thereof, for electrical and/or optical analysis, especially relating to the presence and/or activity of ion channels.

Claims

1. A method for analyzing a plurality of membranous samples, such as cells, vesicles, and cellular organdies, comprising:

selecting a measuring arrangement, comprising (i) a holder, and (ii) a plurality of measurement sites disposed in the holder, each measurement site having a carrier that separates from one another two fluid compartments, the carrier containing an aperture that connects the two compartments, wherein each carrier includes a binding surface adjacent the aperture that is adapted to seal a sample across the aperture, wherein each compartment is in electrical contact with at least one electrode, and wherein the diameter of each aperture immediately adjacent the binding surface is between about 0.3 μ

m and about 7 μ

m;

providing a suspension of membranous samples to one of the fluid compartments of at least two measurement sites;

sealing a first sample from the suspension across a first aperture in the measuring arrangement;

measuring, using at least two of the electrodes, at least one of an electrical potential and a current across at least a portion of the first sample, after the first sample is sealed across the first aperture;

sealing a second sample from the suspension across a second aperture in the measuring arrangement; and

measuring, using at least two of the electrodes, at least one of an electrical potential and a current across at least a portion of the second sample, after the second sample is sealed across the second aperture.

2. The method of claim 1, wherein the sample is selected from the group consisting of cells, vesicles, and biological organelles.

3. The method of claim 1, wherein the carriers are at least substantially planar.

4. The method of claim 1, further comprising moving the sample onto the aperture using an electrical field.

5. The method of claim 1, further comprising permeabilizing a portion of the first and second samples to facilitate measurement of an electrical property of a remaining portion of each sample.

6. The method of claim 5, wherein the step of permeabilizing includes adding a pore former to at least one compartment.

7. The method of claim 5, the sample being a cell, vesiele, or organelle, wherein the step of permeabilizing includes permeabilizing the portion of each sample bound across and facing the aperture.

8. The method of claim 5, the sample being a cell, vesicle, or organelle, wherein the step of permeabilizing includes destroying the portion of each sample bound across and facing the aperture.

9. The method of claim 1, further comprising applying an electrical potential difference across the first and second samples, wherein the step of measuring at least one of an electrical potential difference and a current includes measuring the current necessary for maintaining the applied electrical potential difference.

10. The method of claim 9, further comprising adding a modulator to the fluid compartments containing the first and second samples, wherein the steps of applying an electrical potential difference and measuring the current are repeated fur each of the first and second samples before and after the step of adding the modulator.

11. The method of claim 1, further comprising applying a current across the first and second samples, wherein the step of measuring at least one of an electrical potential difference and a current includes measuring the electrical potential difference necessary for maintaining the applied current.

12. The method of claim 1, further comprising modifying at least one of the sample and the carrier to enhance binding between the sample and the carrier.

13. The method of claim 12, wherein the step of modifying includes treating at least one of the sample and the carrier to enhance electrostatic interactions.

14. The method of claim 12, wherein the step of modifying includes treating at least one of the sample and the carrier to enhance molecule-specific interactions.

15. The method of claim 12, wherein the step of modifying includes treating at least one of the sample and the carrier to enhance multivalent-ion-mediated interactions.

16. The method of claim 12, wherein the step of modifying includes treating at least one of the sample and the carrier to enhance hydrophilic/hydrophobic interactions.

17. The method of claim 1, further comprising cleaning the carriers in a plasma.

18. The method of claim 1, further comprising replacing a solution in at least one compartment with another solution.

19. The method of claim 1, further comprising incorporating membrane proteins into at least one of the first and second samples, after the sample is sealed to the aperture.

20. The method of claim 1, further comprising carrying out an optical measurement on at least one of the first and second samples.

21. The method of claim 20, wherein the optical measurement is a fluorescence measurement.

22. The method of claim 1, wherein the steps of measuring at least one of an electrical potential and a current are performed sequentially over the first and second apertures.

23. The method of claim 1, wherein the steps of measuring at least one of an electrical potential and a current are performed in parallel over the first and second apertures.

24. The method of claim 1, wherein at least one electrode is used with more than one fluid compartment.

25. The method of claim 1, wherein the measuring arrangement further comprises the at least one electrode.

26. The method of claim 1, further comprising:

sealing a third sample across a third aperture in the measuring arrangement; and

measuring, using at least two of the electrodes, at least one of an electrical potential and a current across at least a portion of the third sample, after the third sample is sealed across the third aperture.

27. The method of claim 1, further comprising measuring, using at least two of the electrodes, at least one of an electrical potential and a current across the first and second apertures, before the first and second samples are sealed across the first and second apertures, respectively.

28. The method of claim 1, further comprising measuring, using at least two of the electrodes, at least one of an electrical potential and a current across the first and second apertures, while the first and second samples are sealing across the first and second apertures, respectively.

29. The method of claim 1, wherein the seal between the first and second samples and the first and second apertures, respectively, is tight enough so that the variance of leakage currents through the aperture during electrical measurements lies below the signals to be measured of 0.1-50 pA at V_M=−

60 mV by a factor of 5-10.

30. The method of claim 1, wherein the first and second samples are less than 150 μ

m in diameter.

31. A method for analyzing membranous samples, such as cells, vesicles, and cellular organelles, comprising:

selecting a measuring arrangement, comprising (i) a carrier having a plurality of apertures and a binding surface adjacent each aperture, each aperture being between about 0.3 μ

m and about 7 μ

m in diameter immediately adjacent the binding surface, (ii) at least two fluid compartments, separated by the carrier, each fluid compartment connected to at least one of the other fluid compartments via at least one of the apertures, and (iii) at least two electrodes, each electrode being in electrical contact with at least one of the fluid compartments;

providing a suspension of membranous samples to one or more of the fluid compartments, at least two of the apertures being in fluid contact with a portion of the suspension;

sealing a first sample from the suspension across a first aperture selected from the at least two of the apertures, and sealing a second sample from the suspension across a second aperture selected from the at least two of the apertures; and

measuring, distinguishably, at least one of an electrical potential and a current across at least a portion of each of the first and second samples, following the step of sealing the samples across the apertures.

32. The method of claim 31, wherein the sample is selected from the group consisting of cells, vesicles, and biological organelles.

33. The method of claim 31, wherein the carriers are at least substantially planar.

34. The method of claim 31, further comprising moving the sample onto the aperture using an electrical field.

35. The method of claim 31, further comprising permeabilizing a portion of the first and second samples to facilitate measurement of an electrical property of a remaining portion of each sample.

36. The method of claim 35, wherein the step of permeabilizing includes adding a pore former to at least one compartment.

37. The method of claim 35, the sample being a cell, vesicle, or organelle, wherein the step of permeabilizing includes permeabilizing the portion of each sample bound across and facing the aperture.

38. The method of claim 35, the sample being a cell, vesicle, or organelle, wherein the step of permeabilizing includes destroying the portion of each sample bound across and facing the aperture.

39. The method of claim 31, further comprising applying an electrical potential difference across the first and second samples, wherein the step of measuring at least one of an electrical potential difference and a current includes measuring the current necessary for maintaining the applied electrical potential difference.

40. The method of claim 39, further comprising adding a modulator to the fluid compartments containing the first and second samples, wherein the steps of applying an electrical potential difference and measuring the current are repeated for each of the first and second samples before and after the step of adding the modulator.

41. The method of claim 31, further comprising applying a current across the first and second samples, wherein the step of measuring at least one of an electrical potential difference and a current includes measuring the electrical potential difference necessary for maintaining the applied current.

42. The method of claim 31, further comprising modifying at least one of the sample and the carrier to enhance binding between the sample and the carrier.

43. The method of claim 42, wherein the step of modifying includes treating at least one of the sample and the carrier to enhance electrostatic interactions.

44. The method of claim 42, wherein th. step of modifying includes treating at least one of the sample and the carrier to enhance molecule-specific interactions.

45. The method of claim 42, wherein the step of modifying includes treating at least one of the sample and the carrier to enhance multivalent-ion-mediated interactions.

46. The method of claim 42, wherein the step of modifying includes treating at least one of the sample and the carrier to enhance hydrophilic/hydrophobic interactions.

47. The method of claim 31, further comprising cleaning the carrier in a plasma.

48. The method of claim 31, further comprising replacing a solution in at least one compartment with another solution.

49. The method of claim 31, further comprising incorporating membrane proteins into at least one of the first and second samples, after the sample is sealed to the apertare.

50. The method of claim 31, further comprising carrying out an optical measurement on at least one of the first and second samples.

51. The method of claim 50, wherein the optical measurement is a fluorescence measurement.

52. The method of claim 31, wherein the step of measuring at least one of an electrical potential and a current is performed sequentially over the first and second apertures.

53. The method of claim 31, wherein the step of measuring at least one of an electrical potential and a current is performed in parallel over the first and second apertures.

54. The method of claim 31, wherein at least one electrode is used with more than one fluid compartment.

55. The method of claim 31, further comprising:

sealing a third sample across a third aperture selected from the plurality of apertures; and

measuring, distinguishably, at least one of an electrical potential and a current across at least a portion of each of the first, second, and third samples, following the step of sealing the samples across the apertures.

56. The method of claim 31, further comprising measuring, distinguishably, at least one of an electrical potential and a current across the first and second apertures, before the first and second samples are sealed across the first and second apertures, respectively.

57. The method of claim 31, further comprising measuring, distinguishably, at least one of an electrical potential and a current across the first and second apertures, while the first and second samples are sealing across the first and second apertures, respectively.

58. The method of claim 31, wherein the seal between the first and second samples and the first and second apertures, respectively, is tight enough so that the variance of leakage currents through the aperture during electrical measurements lies below the signals to lie measured of 0.1-50 pA at V_M=−

60 mVby a factor of 5-10.

59. The method of claim 31, wherein the first and second samples are less than 150 μ

m in diameter.

60. A method for analyzing membranous samples, such as cells, vesicles, and cellular organdies, comprising:

selecting a holder having a plurality of measurement sites, each measurement site having a carrier containing an aperture and a binding surface around the aperture, each aperture being between about 0.3 μ

m and about 7 μ

m in diameter immediately adjacent the binding surface, wherein fluid is disposed on opposite sides of the aperture;

providing a suspension of membranous samples to at least two of the measurement sites;

sealing a first sample from the suspension across an aperture at a first of the plurality of measurement sites, and a second sample from the suspension across an aperture at a second of the plurahuy of measurement sites; and

measuring, distinguishably, at least one of an electrical potential difference and a current across at least a portion of each of the first and second samples, following the step of sealing the samples across the apertures.

61. The method of claim 60, wherein the step of measuring at least one of an electrical potential and a current is performed sequentially over the first and second apertures.

62. The method of claim 60, wherein the step of measuring at least one of an electrical potential and a current is performed in parallel over the first and second apertures.

63. The method of claim 60, wherein the step of measuring is performed using at least two electrodes, wherein the electrodes are operatively disposed on opposite sides of the apertures.

64. The method of claim 63, wherein at least one electrode is used with more than one fluid compartment.

65. The method of claim 60, wherein the membranous sample is less than 150 μ

m in diameter.

66. A method for analyzing membranous samples, such as cells, vesicles, and cellular organdies, comprising:

selecting a measuring arrangement, comprising (i) a carrier having a plurality of apertures and a binding surface encircling each aperture, each aperture being between about 0.3 μ

m and about 7 μ

m in diameter immediately adjacent the binding surface, the carrier being adapted so that at least one of the samples can be sealed across at least one of the apertures on the respective binding surface, (ii) at least one sample fluid compartment and at least one reference fluid compartment, in contact via the apertures, and (iii) at least one sample electrode and at least one reference electrode, each sample electrode in contact with at least one of the sample fluid compartments, and each reference electrode in contact with at least one of the reference fluid compartments, wherein the at least one sample electrode and the at least one reference electrode are adapted to apply and/or measure an electrical potential across the apertures;

sealing a first sample across a first aperture in the measuring arrangement, and sealing a second sample across a second aperture in the measuring arrangement; and

measuring, distinguishably, using at least two of the electrodes, at least one of an electrical potential and a current across at least a portion of each of the first and second samples, following the step of sealing the samples across the apertures.

67. The method of claim 66, wherein the membranous sample is less than 150 μ

m in diameter.