US5217026A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Guidewires with lubricious surface and method of their production
Assignee: Hymedix International Inc
•
Filing: 1992-04-06
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Granted: 1993-06-08
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Expires: 2012-04-06
Abstract
Abstract The present invention guidewire involves an elongated, non-hydrogel core element forming an inner part of the device, and an integral outside tubular layer of elastomeric hydrogel ("hydrogel sleeve"). This outer hydrogel layer has unique physical characteristics. They are (a) Gradient of chemical composition with increasing concentration of polar groups in the outward direction away from the core element; (b) Gradient of swelling in contact with water with water content increasing in the outward direction away from the core element; (c) Compressive stress in the outer hydrophilic layer causing the hydrogel in that layer to swell to a water content lower than its equilibrium value in a free-swelling state; and, optionally, (d) Inward-directed radial stress pushing the outside hydrogel layer constantly against the inner core element. The present invention also involves the methods of making these guidewires, including melt extrusion directly onto the core element, coagulation from solution, in situ hydrogel polymer formation, and tubing extrusion followed by consequent shrink-fit over the core.
Inventors
- 👤 George P. Stoy
- 👤 Vladimir A. Stoy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:31
CPC Classifications
A; A61; A61M; A61M25/00; A61M25/0043; A61M25/0045; A61M25/0009; A61M25/01; A61M25/09; A61M2025/09058; A61M2025/09083; A61M2025/09091; A61M2025/09108; Y; Y10; Y10S; Y10S524/00; Y10S524/916
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
99 words
A guidewire for insertion of tubular instruments into a body, which comprises: (a) a core element having sufficient rigidity to be inserted into a body; (b) an outside tubular layer about said core element, forming an elastomeric hydrogel sleeve, said sleeve having; (i) a chemical composition gradient with increasing concentration of polar groups in the outward direction away from said core element; (ii) a swelling gradient represented by increasing water content volumetrically in the outward direction away from said core element; and, (iii) compression stress decreasing the swelling at least in the outer most layer below its equilibrium value.
Claim 2
Dependent Claim
99 words
A guidewire for insertion of tubular instruments into a body, which comprises: (a) a core element having sufficient rigidity to be inserted into a body; (b) an outside tubular layer about said core element, forming an elastomeric hydrogel sleeve, said sleeve having; (i) a chemical composition gradient with increasing concentration of polar groups in the outward direction away from said core element; (ii) a swelling gradient represented by increasing water content volumetrically in the outward direction away from said core element; and, (iii) compression stress decreasing the swelling at least in the outer most layer below its equilibrium value.
Claim 3
Dependent Claim
25 words
The guidewire of claim 1, wherein said hydrogel sleeve further includes an inwardly directed radial stress securing said outside tubular layer to said core element.
Claim 4
Dependent Claim
28 words
The guidewire of claim 1, wherein said core element is made of one or more materials selected from the group consisting of metal, plastic, carbon, glass and ceramics.
Claim 5
Dependent Claim
15 words
The guidewire of claim 1, wherein the core element has a substantially cylindrical cross section.
Claim 6
Dependent Claim
36 words
The guidewire of claim 1, wherein said elastomeric hydrogel sleeve is formed of a material selected from the group consisting of hydrophilic derivatives of acrylic acid, hydrophilic derivatives of methacrylic acid, and crosslinked hydrophilic polyvinylic compounds.
Claim 7
Dependent Claim
19 words
The guidewire of claim 1, wherein said elastomeric hydrogel sleeve is formed of hydrophilic polyurethanes or hydrophilic modified polyacrylonitriles.
Claim 8
Dependent Claim
21 words
The guidewire of claim 1, wherein said polar groups are selected from ionic groups consisting of carboxylic, sulfuric or sulfate groups.
Claim 9
Dependent Claim
44 words
The guidewire of claim 1, wherein said swelling gradient includes a water concentration of said tubular layer near its inner surface of about 25% to about 50% of water by volume, and at least about 90% of water by volume near its outer surface.
Claim 10
Dependent Claim
20 words
The guidewire of claim 1, wherein said tubular layer has a water concentration of at least about 95% by volume.
Claim 11
Dependent Claim
20 words
The guidewire of claim 1, wherein said tubular layer has a thickness of about 0.001 inches to about 0.1 inches.
Claim 12
Independent Claim
115 words
A method of making a guidewire for insertion of tubular instruments into a body, which comprises: (a) by conventional methods, forming a core element having sufficient ridigity to be inserted into a body, from one or more materials selected from the group consisting of metal, plastic, carbon, glass and ceramics; (b) forming an outside tubular layer about said core as an elastomeric hydrogel sleeve, and controlling the formation of the elastomeric hydrogel sleeve to create: (i) a chemical composition gradient with increasing concentration of polar groups in the outward direction away from said core element; and, (ii) a swelling gradient represented by increasing water content volumetrically in the outward direction away from said core element.
Claim 13
Independent Claim
115 words
A method of making a guidewire for insertion of tubular instruments into a body, which comprises: (a) by conventional methods, forming a core element having sufficient ridigity to be inserted into a body, from one or more materials selected from the group consisting of metal, plastic, carbon, glass and ceramics; (b) forming an outside tubular layer about said core as an elastomeric hydrogel sleeve, and controlling the formation of the elastomeric hydrogel sleeve to create: (i) a chemical composition gradient with increasing concentration of polar groups in the outward direction away from said core element; and, (ii) a swelling gradient represented by increasing water content volumetrically in the outward direction away from said core element.
Claim 14
Dependent Claim
25 words
The method of claim 11, wherein said hydrogel sleeve further includes an inwardly directed radial stress securing said outside tubular layer to said core element.
Claim 15
Dependent Claim
15 words
The method of claim 11, wherein said outside tubular layer is formed by melt extrusion.
Claim 16
Dependent Claim
34 words
The method of claim 13, wherein said extrusion is followed by the step of chemical modification by exposing the outer surface to a reagent to create said chemical composition gradient and said swelling gradient.
Claim 17
Dependent Claim
14 words
The method of claim 14, wherein said chemical modification increases concentration of hydrophilic groups.
Claim 18
Dependent Claim
14 words
The method of claim 14, wherein said chemical modification increases concentration of ionic groups.
Claim 19
Dependent Claim
18 words
The method of claim 14, wherein said chemical modification is under such condition that it is diffusion controlled.
Claim 20
Dependent Claim
13 words
The method of claim 13, wherein said hydrogel is derived from hydrophilic urethanes.
Claim 21
Dependent Claim
13 words
The method of claim 13, wherein said hydrogel is derived from modified polyacrylonitriles.
Claim 22
Dependent Claim
21 words
The method of claim 13, wherein said polar groups are selected from ionic groups consisting of carboxylic, sulfuric or sulfate groups.
Claim 23
Dependent Claim
36 words
The method of claim 11, wherein said elastomeric hydrogel sleeve is formed of a material selected from the group consisting of hydrophilic derivatives of acrylic acid hydrophilic derivatives of methacrylic acid, and crosslinked hydrophilic polyvinylic compounds.
Claim 24
Dependent Claim
16 words
The method of claim 11, wherein said outside tubular layer is formed by coagulation from solution.
Claim 25
Dependent Claim
28 words
The method of claim 21, wherein said coagulation from solution is followed by the step of chemical modification to create said chemical composition gradient and said swelling gradient.
Claim 26
Dependent Claim
13 words
The method of claim 22, wherein said hydrogel is derived from hydrophilic urethanes.
Claim 27
Dependent Claim
13 words
The method of claim 22, wherein said hydrogel is derived from modified polyacrylonitriles.
Claim 28
Dependent Claim
21 words
The method of claim 22, wherein said polar groups are selected from ionic groups consisting of carboxylic, sulfuric or sulfate groups.
Claim 29
Dependent Claim
16 words
The method of claim 11, wherein said outside tubular layer is formed by in situ polymerization.
Claim 30
Dependent Claim
13 words
The method of claim 27, wherein said hydrogel is derived from hydrophilic urethanes.
Claim 31
Dependent Claim
13 words
The method of claim 23, wherein said hydrogel is derived from modified polyacrylonitriles.
Claim 32
Dependent Claim
21 words
The method of claim 27, wherein said polar groups are selected from ionic groups consisting of carboxylic, sulfuric or sulfate groups.
Claim 33
Dependent Claim
21 words
The method of claim 11, wherein said polar groups are selected from ionic groups consisting of carboxylic, sulfuric or sulfate groups.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-06-07 | 1996-12-07 | 1997-06-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-06-07 | 2000-12-07 | 2001-06-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-06-07 | 2004-12-07 | 2005-06-08 | $7700.00 | Window Closed / Lapsed |