Method for separating plasma from blood and silanized glass fibres therefor

• US 4,786,603 A
• Filed: 03/04/1987
• Issued: 11/22/1988
• Est. Priority Date: 07/04/1985
• Status: Expired due to Term

• Current Assignee: Boehringer Mannheim GmbH (Roche Holding AG)
• Original Assignee: Boehringer Mannheim GmbH (Roche Holding AG)
• Inventors: Wielinger, Hans, Freitag, Helmut
• Primary Examiner(s): Richman, Barry S.
• Assistant Examiner(s): Hill, Jr., Robert J.
• Application Number:
  US07/021,743
• Time in Patent Office: 629 Days
• Field of Search: 436/69, 436/170, 436/177, 436/148, 422/55-58, 210/508, 210/509, 210/679, 210/500.24, 210/500.26, 435/13, 428/391, 428/392, 428/375, 428/361, 428/401
• US Class Current: 436/69
• CPC Class Codes: A61L 33/0076 Chemical modification of the substrate
• CPC Class Codes: B01D 2239/0421 Rendering the filter material hydrophilic
• CPC Class Codes: B01D 2239/0492 on fibres
• CPC Class Codes: B01D 2239/1233 Fibre diameter
• CPC Class Codes: B01D 39/06 Inorganic material, e.g. asbestos fibres, glass beads or fibres
• CPC Class Codes: B01D 39/2017 the material being filamentary or fibrous
• CPC Class Codes: C03C 25/40 Organo-silicon compounds
• CPC Class Codes: G01N 33/86 involving blood coagulating time or factors, or their receptors
• CPC Class Codes: Y10T 428/2962 Silane, silicone or siloxane in coating
• CPC Class Codes: Y10T 428/2964 Artificial fiber or filament
• CPC Class Codes: Y10T 428/298 Physical dimension
• CPC Class Codes: Y10T 436/255 including use of a solid sorbent, semipermeable membrane, or liquid extraction

Abstract

Hydrophilic glass fibers which have bonded to their surfaces a layer of silane molecules of the formula ##STR1## are useful for the separation of plasma from blood for haemostasiological testing. In the formula: the molecule is bonded at its end oxygen to a surface of a glass fibre; R₁ is C₂ -C₆ alkylene; X is OH, C₁ -C₆ alkoxy, having n carbon atoms and up to (n-1) OH groups in which n is 1-6, or an amino acid or peptide residue; and each of R'"'"'₃ and R"₃ is C₁ -C₆ alkyl, an oxygen bridge to the silicon atom of another silane molecule or an oxygen bridge to the glass surface. The fibres have an average diameter of from 0.2 to 5 microns and a density of 0.1 to 0.5 g/cm³.

Claims

1. An agent for separating plasma from blood for haemostasiological tests which comprises a layer of glass fibres having bonded to their surfaces a layer of silane molecules of the formula ##STR4## wherein each molecule is bonded at its end oxygen to a surface of a glass fibre in the layer of glass fibres,

R₁ is C₂ -C₆ alkylene,

X is hydroxyl, C₁ -C₆ alkoxy, an alkoxy radical having n carbon atoms and up to (n-1) hydroxyl groups in which n is an integer from 1 to 6, or an amino acid or peptide residue;

and each of R'"'"'₃ and R"₃ is C₁ -C₆ alkyl, an oxygen bridge to the silicon atom of another silane molecule, or an oxygen bridge to a glass surface,

said fibres having an average diameter of from 0.2 to 5μ and

said glass fiber layer having density of 0.1 to 0.5 g./cm³.

2. The agent of claim 1, wherein the glass fibres have an average diameter of 0.5 to 2.5μ

.

3. The agent of claim 1 wherein the fibres are layered in a column having a head which is provided with means for applying blood and an end which is provided with means for removing plasma.

4. The agent according to claim 1, wherein R₁ is ethylene or propylene.

5. A multi-layer diagnostic device for detecting blood coagulation parameters, which comprises an uppermost layer the agent of claim 1 wherein the glass fibre layer consists of a glass fibre paper or fleece.

6. The diagnostic device of claim 5, wherein the glass fibre layer is the uppermost layer of said device.

7. The diagnostic device of claim 5, wherein the glass fiber layer is in absorbent contact with a plasma transport layer which, in turn, is in absorbent contact with one or more reagent layers or can be brought into contact therewith.

8. A method for separating plasma from blood which comprises passing whole blood through an agent comprising a layer of glass fibres having bonded to their surfaces a layer of silane molecules of the formula ##STR5## wherein each molecule is bonded at its end oxygen to a surface of a glass fibre in the layer of glass fibres,

R₁ is C₂ -C₆ alkylene,

X is hydroxyl, C₁ -C₆ alkoxy, an alkoxy radical having n carbon atoms and up to (n-1) hydroxyl groups in which n is an integer from 1 to 6, or an amino acid or peptide residue;

and

each of R'"'"'₃ and R"₃ is C₁ -C₆ alkyl, an oxygen bridge to the silicon atom of another silane molecule, or an oxygen bridge to a glass surface, said fibres having an average diameter of from 0.2 to 5μ and

said glass fibre layer having a density of 0.1 to 0.5 g./cm³.

9. The method according to claim 8, in which the glass fibres have an average diameter of from 0.5 to 2.5μ

.

10. The method according to claim 8, wherein R₁ is ethylene or propylene.

11. The method according to claim 8, in which the fibres are layered in a column having a head which is provided with means for applying blood and an end which is provided means for removing plasma.

12. The method according to claim 8, wherein the glass fibre layer consists of a glass fibre paper or fleece and is part of a multi-layer diagnostic device for detecting coagulation parameters which has an uppermost layer.

13. The method according to claim 12, wherein the glass fibre layer is the uppermost layer of said diagnostic device.

14. The method according to claim 12, wherein the glass fibre layer is in absorbent contact with a plasma transport layer which, in turn, is in absorbent contact with one or more reagent layers or can be bought into contact therewith.