Analyte measurement

• US 20040096959A1
• Filed: 12/29/2003
• Published: 05/20/2004
• Est. Priority Date: 12/19/2000
• Status: Abandoned Application

• Current Assignee: LifeScan IP Holdings, LLC
• Original Assignee: Cilag Gmbh International (Johnson & Johnson)
• Inventors: Stiene, Matthias, Allen, John, Richter, Tanja, McAleer, Jerome
• Application Number:
  US10/432,827
• Publication Number:
  US 20040096959A1
• Time in Patent Office: Days
• US Class Current: 435/287.2
• CPC Class Codes: A61B 10/0045 Devices for taking samples of body liquids devices for taking blood samples A61B5/15
• CPC Class Codes: A61B 2010/008 Interstitial fluid
• CPC Class Codes: A61B 5/14514 using means for aiding extraction of interstitial fluid, e.g. microneedles or suction
• CPC Class Codes: A61B 5/1473 invasive, e.g. introduced into the body by a catheter A61B5/1482 takes precedence
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/150213 Venting means
• CPC Class Codes: A61B 5/150358 Strips for collecting blood, e.g. absorbent optical reagent test strips G01N21/8483; chemical reagent test strips G01N33/4875, G01N33/52
• CPC Class Codes: A61B 5/150419 comprising means for capillary action
• CPC Class Codes: A61B 5/15045 comprising means for capillary action
• CPC Class Codes: A61B 5/150755 Blood sample preparation for further analysis, e.g. by separating blood components or by mixing
• CPC Class Codes: A61B 5/15142 Devices intended for single use, i.e. disposable

Abstract

A glucose sensor in the form of a skin patch 2 has a microneedle 4 which painlessly penetrates the skin to draw out interstitial fluid. The interstitial fluid passes to a common entrance port 7. A series of microchannels 8 is provided on the skin patch. The fluid drawn onto the patch is selectively switched between a number of microchannels 8 by means of electro-osmotic pumps 10 and hydrophobic gates 12. Each microchannel 8 has an electrochemical detector 11 for sensing gluocse concentration.

Also disclosed is a monlithic device with an integrated lance 83.

Claims

1. A device for measuring the concentration of an analyte in a fluid, comprising a support member and a plurality of analyte sensing means provided thereon for measuring said concentration, wherein said device further comprises a plurality of conduits such that each of said sensing means has a conduit associated therewith, said conduits serving in use to direct said fluid to respective sensing means.

2. A device as claimed in claim 1 comprising a penetration member, preferably integrally formed, sufficiently short only to penetrate the cutaneous layer of skin, most.

3. A device as claimed in claim 1 or 2 comprising at least one microchannel for conveying a interstitial fluid to one or more of the sensing means.

4. A device as claimed in claim 1, 2 or 3 wherein at least some of said sensing means are the same or are for measuring the same analyte.

5. A device as claimed in claim 4 which is arranged such that in use the plurality of sensing means take measurements of the fluid at different times to enable monitoring of the concentration of the analyte in the fluid over a period of time.

11. A device as claimed in any preceding claim comprising integral fluid extraction means for extracting a body fluid from a human of animal body fluid.

14. A device as claimed in claim 11, 12 or 13 wherein said fluid extraction means comprises a skin penetration member.

15. A device as claimed in claim 14 wherein said skin penetration member is of such a length that it penetrates only the cutaneous layer of skin, not the sub-cutaneous layer.

16. A device as claimed in claim 15 wherein said skin penetration member is adapted to extract interstitial fluid.

19. A device as claimed in any of claims 14 to 18 comprising a microneedle for extracting interstitial fluid.

20. A device as claimed in any preceding claim which is adapted to measure glucose concentration.

21. A device as claimed in any preceding claim comprising analyte sensing means including a mediated amperometric enzyme electrode.

22. A device as claimed in claim 21 adapted to utilise ferrocene-mediated electron transfer from a glucose-oxidase catalysed reaction.

23. A device as claimed in any preceding claim comprising a plurality of analyte sensing means.

24. A device as claimed in any preceding claim which is arranged to measure an analyte concentration directly.

25. A device as claimed in any preceding claim which is suitable for attachment to the skin of a subject for measuring the concentration of an analyte in blood or interstitial fluid of the subject.

26. A device as claimed in claim 25 comprising means for attaching the device to the skin.

28. A device as claimed in any preceding claim arranged to take measurements at predetermined intervals.

29. A device as claimed in claim 28 comprising flow control means for influencing the flow of fluid to the sensing means.

30. A device as claimed in claim 29 wherein the flow control means comprises a hydrophobic gate disposed in a microchannel.

31. A device as claimed in claim 30 comprising means for changing the hydrophobicity of said gate.

32. A device as claimed in claim 31 comprising a hydrophilic base material covered by a hydrophobic material and further comprising means for exposing said hydrophilic base material.

33. A device as claimed in claim 30 comprising pumping means arranged to apply a pressure to liquid in said microchannel sufficient to breach said hydrophobic gate.

34. A device as claimed in any preceding claim comprising a plurality of analyte sensing means, said device being arranged to direct fluid sequentially to each of the sensing means.

35. A device as claimed in claim 34 comprising or being adapted to interface with, control means for generating signals to control said direction of the fluid to the sensing means.

36. A device as claimed in claim 35 comprising said control configured so as to allow a user to specify when a measurement is to be made.

37. A device as claimed in claim 35 or 36 comprising calorimetric transduction means.

38. A device as claimed in any of claims 34 to 37 comprising a common fluid collection region arranged so as in use to be in fluid communication with a body fluid to be measured.

39. A device as claimed in claim 38 wherein each of said sensing means is in selective fluid communication with said common collection region.

41. A device as claimed in any of claims 34 to 40 comprising a sensing means for making a substantially continuous measurement of the concentration of a substance.

52. A device as claimed in any preceding claim which is suitable for attachment to a user'"'"'s skin comprising transfer means for transferring said a body fluid from the user'"'"'s body to a sensitive part of the device.

53. A device as claimed in claim 52 wherein said transfer means is arranged to transfer a fluid to the upstream end of a microchannel.

54. A device as claimed in claim 52 or 53 wherein said transfer means comprises a needle.

55. A device as claimed in claim 54 wherein said needle is a microneedle of such a length that it penetrates the cutaneous layer of skin, but not the sub-cutaneous layer.

56. A device as claimed in claim 54 or 55 wherein the needle comprises an aperture on a side surface thereof.

57. A device as claimed in any of claims 52 to 56 wherein said transfer means is invasive or semi-invasive, the device further comprising means for applying pressure to the user'"'"'s skin in the region of penetration by said transfer means.

58. A device as claimed in any preceding claim comprising display means for displaying the concentration of an analyte being measured.

59. A device as claimed in claim 58 wherein said display means is separate from the rest of the device and receives data therefrom by telemetry.

60. A device as claimed in any preceding claim comprising means for administering a substance to a user on the device on the basis of a measured analyte concentration.

67. A device as claimed in any preceding claim comprising electro-osmotic flow control means comprising a plurality of driving electrodes, said driving electrodes being provided substantially on one side of a channel.

68. A device as claimed in claim 67 wherein said driving electrodes extend circumferentially around an arcuate wall of the channel.

69. A device as claimed in any preceding claim comprising a main support member and a second substrate laminated to the main support member, said second substrate layer having one or more electrodes formed thereon.

70. A device as claimed in claim 69 wherein said second substrate is arranged to close a channel provided on the main support member.

76. Apparatus for measuring an analyte optically comprising a device as claimed in any preceding claim for measuring said analyte and a separate test meter including light sensitive means, wherein said measuring device and said test meter are arranged such that in use the light sensitive means views said analyte along a channel of the measuring device.

6. A device for measuring the concentration of an analyte in a fluid, comprising a support member, analyte sensing means provided thereon for measuring said concentration and a microchannel in fluid communication with said analyte sensing means for conveying said fluid to said sensing means.

7. A device as claimed in claim 6 wherein the analyte sensing means comprises one or more reagents to react with said analyte and thereby give a measurable output.

8. A device as claimed in claim 7 wherein the reagent or at least one of the reagents is provided on a wall of the microchannel.

9. A device for measuring the concentration of an analyte in a fluid, comprising a support member and a microchannel provided on said support member for conveying said fluid across the support member, wherein one or more reagents for reacting with said analyte is coated on a wall of the microchannel.

10. A device as claimed in claim 9 comprising means for measuring the output of a reaction between the analyte and the reagent.

12. A device for measuring the concentration of an analyte in a fluid, comprising a support member, means provided on the support member for sensing said analyte, wherein said support member further comprises fluid extraction means arranged to direct fluid to said analyte sensing means via a conduit on the support member.

13. A device as claimed in claim 12 wherein said conduit comprises a microchannel.

17. A device for measuring the concentration of an analyte in a bodily fluid, comprising skin penetration means, said penetration means being sufficiently short so as to penetrate only the cutaneous layer of skin without penetrating the sub-cutaneous layer, and a support member, said support member comprising an analyte sensing site and a microchannel for conducting said body fluid from said penetration member to said analyte sensing site.

18. A device as claimed in claim 17 wherein said penetration means is integral with said support layer.

27. A device for measuring the concentration of a given analyte in a body fluid comprising means for attaching the device to the skin of a subject and a plurality of sensing means for making a plurality of measurements of said concentration over a period of time.

40. A device for making a plurality of measurements of the concentration of an analyte in a fluid comprising a common sample collection site in fluid communication with the fluid to be measured and a plurality of sensing means for measuring said concentration.

42. A device for measuring the concentration of an analyte in a fluid comprising a sensing means for measuring said concentration substantially continuously and calibration sensing means for performing at least one calibration measurement.

43. A device as claimed in claim 42 comprising a plurality of individual sensing means to allow a series of periodic calibration measurements to be performed.

46. A device as claimed in any of claims 42 to 45 comprising flow control means associated with fluid conduits for conducting fluid to the calibration sensing means.

47. A device as claimed in claim 46 wherein said flow control means comprises an electro-osmotic pumping arrangement.

48. A device as claimed in any of claims 42 to 47 which is suitable for attachment to a user'"'"'s skin.

49. A device as claimed in any of claims 42 to 48 wherein said calibration sensing means comprises a single use sensor.

50. A device as claimed in any of claims 42 to 49 wherein said calibration sensing means is downstream of the continuous sensing means.

51. A device as claimed in any of claims 42 to 50 comprising one or more microchannels for conveying the fluid to be measured to the sensing means.

44. A device as claimed in claim 44 wherein the continuous sensing means and calibration sensing means are provided on a common base member.

45. A device as claimed in claim 44, wherein said common base member comprises a patch or the like for attachment to the skin of a user.

61. An device for administering a substance to a user comprising a measuring device for measuring the concentration of an analyte in a bodily fluid from said user, said measuring device comprising a plurality of analyte sensing means and at least one conduit, preferably a microchannel, for conveying said body fluid to at least one of the sensing means;

the apparatus further comprising administration means for administering said substance to said user on the basis of said measurement of concentration.

62. A device as claimed in claim 61 wherein the measuring device comprises a self-adhesive patch for attachment to the skin of a user.

63. A device as claimed in claim 61 or 62 wherein said administration means is integrated with the measuring device.

64. An device as claimed in claim 63 wherein the administration means comprises a reservoir on or in the measuring device for dispensing the substance.

65. An device as claimed in claim 64 further comprising a pump for removing said substance from the reservoir.

66. An device as claimed in claim 65 comprising a single pump for both administering said substance to a user'"'"'s body and for drawing out blood or interstitial fluid, to a sensing means for making an analyte concentration measurement.

71. A device for measuring the concentration of an analyte in a fluid comprising a support member having an open channel on a surface thereof the support member;

and a second layer laminated onto said support member so as to close said channel.

72. A device as claimed in claim 71 wherein said channel is a microchannel.

73. A device as claimed in claim 71 or 72 comprising an integrated skin penetration member is provided which is also open on one side.

74. A device as a claimed in claim 73 wherein said skin penetration member is arranged so that upon insertion into skin, the skin itself effectively forms a wall of

75. A device for obtaining fluid through human or animal skin, comprising a skin penetration member having at least one longitudinal side open, the other sides being arranged so as effectively to cause the penetrated skin to act as the remaining longitudinal side of the member when the penetration member is inserted into the skin.

77. Apparatus for measuring the light from an assay comprising an elongate conduit portion along which a sample fluid is drawn in use and a light sensitive means arranged to be sensitive to light coming substantially from the longitudinal axis of said conduit portion.

78. A disposable skin patch comprising an elongate conduit portion along which a sample fluid is drawn in use and a moulded plastics lens over said conduit portion.

79. A test meter for use with disposable skin patch as claimed in claim 78 comprising a light sensitive element arranged, in use, to sit over said lens when the meter is placed over the patch.

80. A method of measuring the amount of an analyte in a sample of liquid comprising providing an electrochemical measuring device having a sensor electrode within a microchannel, introducing said sample liquid into said microchannel, and measuring an aggregate current passed by said electrode to give an indication of said amount of analyte in the sample.

81. An electrochemical device for measuring the amount of an analyte in a sample of liquid comprising a sensor electrode disposed within a microchannel and means for measuring an aggregate current passed by said electrode in use to give an indication of said amount of analyte in the sample.

82. A method of making a device for measuring the concentration of a substance in a liquid comprising forming a first channel in a substrate material, fitting said channel at least partially with an electrically conductive material, and forming a second channel so as to intersect said first channel, thereby forming two conductive portions on respective opposite sides of the second channel.

83. A method of fabricating a device for measuring the concentration of an analyte in a fluid comprising providing a support member, forming an open channel on a surface of the support member and laminating a second layer onto said support member so as to close said channel.

84. An apparatus for obtaining and analyzing a sample of a body fluid from a skin layer, said apparatus comprising:

a support member;

a channel formed on said support chamber;

said channel having an entrance for receiving said body fluid;

an analyte sensor carried on said support member and positioned to sense an analyte in said fluid within said channel;

a flow controller for influencing a flow of fluid within said channel to said sensor.

85. An apparatus according to claim 84 further comprising a fluid extraction member for directing fluid from said skin layer to said entrance.

86. An apparatus according to claim 85 further comprising a flow restrictor between said fluid extraction member and said channel.

87. An apparatus according to claim 84 further comprising a waste reservoir in fluid flow communication with said channel.

88. An apparatus according to claim 84 wherein said flow controller includes a flow inhibitor in said channel inhibiting flow of said body fluid into said channel and a reliever for permitting discharge of said inhibitor from said channel to permit said fluid to flow into said channel.

89. An apparatus according to claim 88 wherein said flow inhibitor is an inhibitor fluid in said channel and said reliever includes a switch for permitting selective release of said inhibitor fluid from said channel.

90. An apparatus according to claim 89 wherein said switch includes a membrane blocking passage of said inhibitor fluid from said channel and selectively controllable electrodes for removing said membrane.

91. An apparatus according to claim 90 wherein said membrane is selected to be at least partially destroyed by energization of said electrodes.

92. An apparatus according to claim 89 wherein said inhibitor fluid is air and said switch vents said air from said channel.

93. An apparatus according to claim 84 wherein said flow controller includes a hydrophobic gate.

94. An apparatus according to claim 93 wherein said hydrophobic gate includes a hydrophobic length of said channel.

95. An apparatus according to claim 84 wherein said flow controller includes a bubble disposed in said channel with a vent to said channel to permit selective discharge of said bubble from said channel.

96. An apparatus according to claim 84 wherein said flow controller further comprises a pumping mechanism for urging fluid flow past said flow controller.

97. An apparatus according to claim 96 wherein said pumping mechanism is an electro-osmotic pump.

98. An apparatus according to claim 96 wherein said pumping mechanism is automatically controllable by a controller.

99. An apparatus according to claim 96 wherein said pumping mechanism is selectively controllable by a user.

100. An apparatus according to claim 84 wherein:

said channel is one of a plurality of channels each formed on said support chamber by forming channel defining walls on a said support member and each having an entrance for receiving said body fluid;

said analyte sensor is one of a plurality of analyte sensors each associated with a respective one of said plurality of channels.

101. An apparatus according to claim 100 wherein said controller operates to direct flow into a subsequent one of said plurality of channels after a residence time of said body fluid in a preceding one of said plurality of channels.

102. An apparatus according to claim 100 wherein each of said entrances is connected to a common source of said fluid.

103. An apparatus according to claim 100 wherein said plurality of channels and associated sensors include:

at least a first continuous sensor for sensing a concentration of an analyte in fluid within said channel associated with said continuous sensor; and

at least a first calibration sensor for performing as least one calibration measurement of a concentration of an analyte in fluid within said channel associated with said calibration sensor.

105. An apparatus according to claim 84 further comprising an administrator for administering a substance to a user based upon a measuring based upon a sensing of said analyte sensor.

121. An apparatus according to claim 86 further comprising a flow controller for influencing a flow of fluid within said channel to said sensor.

122. An apparatus according to claim 86 wherein:

said channel is one of a plurality of channels each formed on said support chamber by forming channel defining walls on a said support member and each having an entrance for receiving said body fluid;

said analyte sensor is one of a plurality of analyte sensors each associated with a respective one of said plurality of channels.

123. An apparatus according to claim 101 wherein each of said entrances is connected to a common source of said fluid.

124. An apparatus according to claim 101 wherein said plurality of channels and associated sensors include:

at least a first continuous sensor for sensing a concentration of an analyte in fluid within said channel associated with said continuous sensor; and

at least a first calibration sensor for performing as least one calibration measurement of a concentration of an analyte in fluid within said channel associated with said calibration sensor.

157. An apparatus according to claim 84 further comprising an administrator for administering a substance to a user based upon a measuring based upon a sensing of said analyte sensor.

158. An apparatus according to claim 84 wherein said analyte sensor includes a light sensor disposed to be sensitive to light coming substantially from a longitudinal axis of said channel.

104. A method of continuously sampling and measuring an analyte comprising:

extracting a fluid into a common collection port;

directing said fluid along a channel towards an analyte sensing means;

performing at least an analyte measurement on the fluid;

switching the flow of fluid from one channel to sequentially at least another channel after a certain period of time; and

performing at least a further analyte measurement.

106. An apparatus for obtaining and analyzing a sample of a body fluid from a skin layer, said apparatus comprising:

a support member;

a channel formed on said support chamber by forming channel defining wall on a said support member;

said channel having an entrance for receiving said body fluid;

said channel having a minute size with a volume less than 200 nanoliters;

an analyte sensor carried on said support member and positioned to sense an analyte in said fluid within said channel.

107. An apparatus according to claim 106 wherein said channel has a longitudinal dimension less than 10 mm.

108. An apparatus according to claim 106 wherein said channel has a lateral dimension less than 200 micrometres.

109. An apparatus according to claim 108 wherein said lateral dimension is greater than 10 micrometres.

110. An apparatus according to claim 106 wherein said analyte sensor includes a reagent deposited on said wall for reacting with an analyte of said fluid when said fluid is within said channel.

111. An apparatus according to claim 106 further comprising a fluid extraction member for directing fluid from said skin layer to said entrance.

112. An apparatus according to claim 111 wherein said fluid extraction member is a penetration member for penetrating into only a cutaneous layer of said skin layer and said fluid extraction member has a fluid pathway for fluid to flow from said cutaneous layer to said entrance of said channel.

113. An apparatus according to claim 112 comprising a plurality of said fluid extraction members.

114. An apparatus according to claim 112 wherein said penetration member is a hollow needle with a bore of said needle defining said fluid pathway.

115. An apparatus according to claim 112 wherein said penetration member is a lance having opposing surfaces defining said fluid pathway and with said fluid pathway open to an exterior of said lance.

116. An apparatus according to claim 111 wherein said fluid extraction member includes means for iontophoretic transfer of fluid from said skin layer to said entrance.

117. An apparatus according to claim 111 wherein said fluid extraction member includes means for ultra-sonic transfer of fluid from said skin layer to said entrance.

118. An apparatus according to claim 111 wherein said fluid extraction member includes means for suction-assisted transfer of fluid from said skin layer to said entrance.

119. An apparatus according to claim 111 further comprising an electric field generator for stimulating the skin layer and urging fluid to flow to said entrance.

120. An apparatus according to claim 119 wherein said fluid extraction member includes an electrode which comprises a portion of said electric field generator.

125. An apparatus according to claim 106 wherein said analyte sensor includes an electro-chemical sensor.

126. An apparatus according to claim 106 wherein said analyte sensor includes a plurality of electrodes.

127. An apparatus according to claim 106 wherein at least one of said electrodes is an electrically conductive material deposited in said channel.

128. An apparatus according to claim 106 wherein said channel is formed in an electrically conductive material with said material comprising at least one of said electrodes.

129. An apparatus according to claim 106 wherein said analyte sensor includes a calorimetric sensor.

130. An apparatus according to claim 106 further comprising an administrator for administering a substance to a user based upon a measuring based upon a sensing of said analyte sensor.

131. An apparatus for obtaining and analyzing a sample of a body fluid from a skin layer, said apparatus comprising:

a support member;

a channel formed on said support chamber by forming channel defining wall on a said support member;

said channel having an entrance for receiving said body fluid;

said channel having a reagent deposited on said wall for reacting with an analyte of said fluid when said fluid is within said channel.

132. An apparatus according to claim 131 wherein said channel has a volume less than 200 nanoliters.

133. An apparatus according to claim 132 wherein said channel has a longitudinal dimension less than 10 mm.

134. An apparatus according to claim 132 wherein said channel has a lateral dimension less than 500 micrometres.

135. An apparatus according to claim 134 wherein said lateral dimension is less than 200 micrometres.

136. An apparatus according to claim 135 wherein said lateral dimension is greater than 10 micrometres

137. An apparatus according to claim 131 further comprising a fluid extraction member for directing fluid from said skin layer to said entrance.

138. An apparatus according to claim 137 wherein said fluid extraction member is a penetration member for penetrating into only a cutaneous layer of said skin layer and said fluid extraction member has a fluid pathway for fluid to flow from said cutaneous layer to said entrance of said channel.

139. An apparatus according to claim 138 wherein said penetration member is a hollow needle with a bore of said needle defining said fluid pathway.

140. An apparatus according to claim 138 wherein said penetration member is a lance having opposing surfaces defining said fluid pathway and with said fluid pathway open to an exterior of said lance.

141. An apparatus according to claim 131 further comprising a flow controller for influencing a flow of fluid within said channel to a portion of said channel containing said reagent.

142. An apparatus according to claim 131 wherein:

said channel is one of a plurality of channels each formed on said support chamber by forming channel defining walls on a said support member and each having an entrance for receiving said body fluid;

each of said channels provided with a respective reagent on a defining wall of said channels.

143. An apparatus according to claim 142 wherein each of said entrances is connected to a common source of said fluid.

144. An apparatus according to claim 142 wherein said plurality of channels includes:

at least a first continuous sensor for sensing a concentration of an analyte in fluid within said channel associated with said continuous sensor; and

at least a first calibration sensor for performing as least one calibration measurement of a concentration of an analyte in fluid within said channel associated with said calibration sensor.

145. An apparatus for obtaining and analyzing a sample of a body fluid from a skin layer, said apparatus comprising:

a support member;

a channel formed on said support chamber by forming channel defining wall on a said support member;

said channel having an entrance for receiving said body fluid;

a fluid extraction member for directing fluid from said skin layer to said entrance;

said channel having a minute size with a volume less than 200 nanoliters;

an analyte sensor carried on said support member and positioned to sense an analyte in said fluid within said channel.

146. An apparatus according to claim 145 wherein said channel has a longitudinal dimension less than 10 mm.

147. An apparatus according to claim 145 wherein said channel has a lateral dimension is less than 200 micrometres.

148. An apparatus according to claim 147 wherein said lateral dimension is greater than 10 micrometres.

149. An apparatus according to claim 145 wherein said analyte sensor includes an electrochemical sensor positioned to be in contact with said fluid when said fluid is within said channel.

150. An apparatus according to claim 145 wherein said fluid extraction member is a penetration member for penetrating into only a cutaneous layer of said skin layer and said fluid extraction member has a fluid pathway for fluid to flow from said cutaneous layer to said entrance of said channel.

151. An apparatus according to claim 150 wherein said penetration member is a hollow needle with a bore of said needle defining said fluid pathway.

152. An apparatus according to claim 150 wherein said penetration member is a lance having opposing surfaces defining said fluid pathway and with said fluid pathway open to an exterior of said lance.

153. An apparatus according to claim 145 further comprising a flow controller for influencing a flow of fluid within said channel to said sensor.

154. An apparatus according to claim 145 wherein:

said channel is one of a plurality of channels each formed on said support chamber by forming channel defining walls on a said support member and each having an entrance for receiving said body fluid;

said analyte sensor is one of a plurality of analyte sensors each associated with a respective one of said plurality of channels.

155. An apparatus according to claim 154 wherein each of said entrances is connected to a common source of said fluid.

156. An apparatus according to claim 154 wherein said plurality of channels and associated sensors include:

at least a first continuous sensor for sensing a concentration of an analyte in fluid within said channel associated with said continuous sensor; and

at least a first calibration sensor for performing as least one calibration measurement of a concentration of an analyte in fluid within said channel associated with said calibration sensor.

159. An apparatus for obtaining and analyzing a sample of a body fluid from a skin layer, said apparatus comprising:

a support member;

a plurality of channels each formed on said support chamber by forming channel defining walls on a said support member;

each of said channels having an entrance for receiving said body fluid;

a plurality of analyte sensors each associated with a respective one of said plurality of channels, each of said analyte sensors carried on said support member and positioned to sense an analyte in said fluid within said respective one of said plurality of channels.

160. An apparatus according to claim 159 wherein said channel has a minute size with a lateral dimension less than 500 micrometres.

161. An apparatus according to claim 159 wherein said channel has a volume less than 200 nanoliters.

162. An apparatus according to claim 161 wherein said channel has a longitudinal dimension less than 10 mm.

163. An apparatus according to claim 160 wherein said lateral dimension is less than 200 micrometres.

164. An apparatus according to claim 163 wherein said lateral dimension is greater than 10 micrometres

165. An apparatus according to claim 159 wherein said analyte sensor includes an electrochemical sensor positioned to be in contact with said fluid when said fluid is within said channel.

166. An apparatus according to claim 159 further comprising a fluid extraction member for directing fluid from said skin layer to said entrance.

167. An apparatus according to claim 166 wherein said fluid extraction member is a penetration member for penetrating into only a cutaneous layer of said skin layer and said fluid extraction member has a fluid pathway for fluid to flow from said cutaneous layer to said entrance of said channel.

168. An apparatus according to claim 167 wherein said penetration member is a hollow needle with a bore of said needle defining said fluid pathway.

169. An apparatus according to claim 167 wherein said penetration member is a lance having opposing surfaces defining said fluid pathway and with said fluid pathway open to an exterior of said lance.

170. An apparatus according to claim 159 wherein each of said entrances is connected to a common source of said fluid.

171. An apparatus according to claim 159 wherein said plurality of channels and associated sensors include:

at least a first continuous sensor for sensing a concentration of an analyte in fluid within said channel associated with said continuous sensor; and

at least a first calibration sensor for performing as least one calibration measurement of a concentration of an analyte in fluid within said channel associated with said calibration sensor.

172. An apparatus according to claim 159 further comprising an administrator for administering a substance to a user based upon a measuring based upon a sensing of said analyte sensors.

173. A method of making a device for measuring the concentration of a substance in a liquid, said method comprising:

forming a first channel in a substrate material;

fitting said channel at least partially with an electrically conductive material;

forming a second channel so as to intersect with said first channel.

174. A method of fabricating a device for measuring the concentration of an analyte in a fluid, said method comprising:

forming a support member;

forming an open channel on a surface of the support member;

laminating a layer onto said support member so as to close said channel.

175. An apparatus according to claim 174 wherein said laminate layer contains electrodes disposed to be in contact with said open channel.

176. An apparatus according to claim 175 wherein said electrodes are formed through a screen-printing process.