초록 ▼

The present invention relates generally to variable stiffness transcutaneous medical devices including a distal portion designed to be more flexible than a proximal portion. The variable stiffness can be provided by a variable pitch in one or more wires of the device, a variable cross-section in one

The present invention relates generally to variable stiffness transcutaneous medical devices including a distal portion designed to be more flexible than a proximal portion. The variable stiffness can be provided by a variable pitch in one or more wires of the device, a variable cross-section in one or more wires of the device, and/or a variable hardening and/or softening in one or more wires of the device.

대표청구항 ▼

What is claimed is: 1. An analyte sensor, the sensor comprising an elongated flexible portion, wherein the elongated flexible portion comprises a first electrode and a second electrode at least partially surrounding at least a portion of the first electrode, wherein the first and/or second electrod

What is claimed is: 1. An analyte sensor, the sensor comprising an elongated flexible portion, wherein the elongated flexible portion comprises a first electrode and a second electrode at least partially surrounding at least a portion of the first electrode, wherein the first and/or second electrode is configured to produce a signal indicative of an analyte concentration in a host, and wherein the second electrode provides a variable stiffness of the sensor by a variable stiffness of the material of the second electrode and/or by a variable pitch of a helical configuration of the second electrode along at least a portion of its length. 2. The sensor of claim 1, further comprising an insulator located between the first electrode and the second electrode. 3. The sensor of claim 1, wherein the variable stiffness of the second electrode is provided by a variable cross-section of the second electrode. 4. The sensor of claim 1, wherein the variable stiffness of the second electrode is provided by a variable hardness of the second electrode. 5. The sensor of claim 4, wherein the variable hardness is produced by subjecting the second electrode to an annealing process. 6. The sensor of claim 1, wherein the wherein the variable stiffness of the second electrode is provided by a variable diameter. 7. The sensor of claim 1, wherein a distal portion of the sensor is more flexible than a proximal portion of the sensor. 8. The sensor of claim 1, wherein an intermediate portion of the sensor is more flexible than at least one of a distal portion of the sensor and a proximal portion of the sensor. 9. The sensor of claim 1, wherein a distal portion of the sensor is stiffer than at least one of an intermediate portion of the sensor and a proximal portion of the sensor. 10. The sensor of claim 1, wherein the first electrode comprises a solid cross-section. 11. The sensor of claim 1, wherein the sensor is configured and arranged such that after the sensor is transcutaneously inserted, the entire portion of the sensor that is in vivo directly contacts tissue. 12. The sensor of claim 1, wherein the elongated flexible portion comprises a distal portion configured and arranged with a flexibility that minimizes mechanical stresses caused by motion of the host. 13. The sensor of claim 1, further comprising sensor electronics adapted for mounting on a skin of a host, wherein the sensor electronics comprise electrical contacts configured and arranged for releasable connection with electrical contacts associated with the first and second electrodes. 14. The sensor of claim 13, wherein the elongated flexible portion comprises a proximal portion is configured and arranged with a stiffness that maintains a stable connection between the electrical contacts associated with the first and second electrodes and the electrical contacts of the sensor electronics housing. 15. The sensor of claim 1, wherein the sensor is configured to absorb a relative movement between an in vivo portion and an ex vivo portion. 16. An analyte sensor, the sensor comprising an in vivo portion adapted for insertion into a host and an ex vivo portion adapted for operable connection to a device that remains external to the host, wherein the in vivo portion of the sensor comprises a first electrode twisted with or around a second electrode along a length of the sensor in such a way that a stiffness of the sensor gradually changes along a length of the sensor where the first electrode is located, and wherein the first and/or second electrode is configured to produce a signal indicative of an analyte concentration in a host. 17. The sensor of claim 16, wherein the ex vivo portion is stiffer than the in vivo portion. 18. The sensor of claim 16, wherein an intermediate portion is more flexible than at least one of the in vivo portion and the ex vivo portion. 19. The sensor of claim 18, wherein the in vivo portion comprises a tip on an end of the sensor that is stiffer than a substantial portion of the sensor. 20. The sensor of claim 16, wherein at least one electrode comprises a wire in a helical configuration, and wherein a change in stiffness is provided by a varying a cross-section of the wire. 21. The sensor of claim 16, wherein the sensor is configured to absorb a relative movement between the in vivo portion and the ex vivo portion. 22. The sensor of claim 16, wherein the device comprises a housing adapted for mounting on a skin of a host, wherein the housing comprises electrical contacts operably connected to the sensor. 23. The sensor of claim 22, wherein the ex vivo portion of the sensor has a preselected stiffness to maintain a stable connection between the sensor and the electrical contacts. 24. The sensor of claim 16, wherein the in vivo portion of the sensor has a preselected flexibility to minimize mechanical stresses caused by motion of the host. 25. The sensor of claim 16, wherein a stiffness of the ex vivo portion of the sensor is greater than a stiffness of the in vivo portion of the sensor. 26. The sensor of claim 16, wherein at least one electrode comprises a wire, and wherein a change in stiffness is provided by a varying a hardness of the wire. 27. The sensor of 26, wherein the change is produced by subjecting the wire to an annealing process. 28. The sensor of claim 16, wherein an intermediate portion of the sensor is more flexible than at least one of the in vivo portion and the ex vivo portion. 29. The sensor of claim 28, wherein the in vivo portion comprises a tip on an end of the sensor that is stiffer than a substantial portion of the sensor. 30. The sensor of claim 16, further comprising a membrane covering the first and second electrodes. 31. The sensor of claim 16, wherein the first electrode at least partially surrounds the second electrode. 32. The sensor of claim 16, further comprising an insulator located between the first electrode and the second electrode. 33. The sensor of claim 16, wherein the second electrode comprises a solid cross-section. 34. The sensor of claim 16, wherein one of the first and second electrodes comprises a first working electrode and the other of the first and second electrodes comprises a second working electrode. 35. The sensor of claim 16, wherein the second electrode comprises a working electrode and the first electrode comprises a reference electrode. 36. The sensor of claim 16, wherein the sensor is configured and arranged such that after the sensor is transcutaneously inserted, the entire portion of the sensor that is in vivo directly contacts tissue. 37. An analyte sensor configured to produce a signal indicative of an analyte concentration in a host, the sensor comprising an in vivo portion adapted for insertion into a host and an ex vivo portion adapted for operable connection to a device that remains external to the host, wherein the in vivo portion of the sensor comprises a first electrode twisted with or around a second electrode along a length of the sensor in such a way that that a stiffness of the sensor gradually changes along a length of the sensor where the first electrode is located, wherein the ex vivo portion is stiffer than the in vivo portion, wherein at least one electrode comprises a wire in a helical configuration, and wherein the difference in stiffness between the ex vivo portion and the in vivo portion is provided by a varying pitch of the helical configuration. 38. An analyte sensor, the sensor comprising an in vivo portion adapted for insertion into a host and an ex vivo portion adapted for operable connection to a device that remains external to the host, wherein the in vivo portion of the sensor comprises a first electrode twisted with or around a second electrode along a length of the sensor in such a way that a stiffness of the sensor gradually changes along a length of the sensor where the first electrode is located, wherein the first and/or second electrode is configured to produce a signal indicative of an analyte concentration in a host and wherein the first electrode provides the change in stiffness of the sensor. 39. An analyte sensor, the sensor comprising an elongated flexible portion, wherein the elongated flexible portion comprises a first electrode and a second electrode at least partially surrounding at least a portion of the first electrode, wherein the first and/or second electrode is configured to produce a signal indicative of an analyte concentration in a host, and wherein the second electrode provides a variable stiffness of the sensor by a variable stiffness of the material of the second electrode along at least a portion of its length.