US4648975A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of using improved silica-based chromatographic supports containing additives
Assignee: Individual
•
Filing: 1986-02-27
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Granted: 1987-03-10
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Expires: 2006-02-27
Abstract
Abstract Silica-based chromatographic and reactive materials are disclosed with surfaces modified to contain or to be coated with oxides, hydrous oxides, hydroxides, carbonates or silicates of aluminum, iron, or other suitable metals such as zirconium or titanium. The materials exhibit good resistance to dissolution and resulting loss of activity or clogging. This good resistance is particularly evident even in the high pH region (above 8-9) and in the high temperature region (above 35° C.) where the dissolution rates and solubilities of aluminosilicates and of trivalent iron oxides are much smaller than those of silica.
Inventors
- 👤 Aaron Barkatt
- 👤 Pedro B. Macedo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 04:44
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/281; B01J20/282; B01J20/283; B01J20/02; B01J20/0203; B01J20/0225; B01J20/0229; B01J20/0248; B01J20/10; B01J20/103; B01J20/28; B01J20/28002; B01J20/28004; B01J20/286; B01J20/30; B01J20/3085; B01J20/3092; B01J20/32; B01J20/3202; B01J20/3204; B01J20/3231; B01J20/3234; B01J20/3236; B01J20/3242; B01J20/3244; B01J20/3246; C; C03; C03C; C03C1/00; C03C1/002; C03C11/00; C03C11/005; C03C23/00; C03C23/0095; B01J2220/00; B01J2220/50; B01J2220/54; B01J2220/56; B01J2220/58
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
102 words
A process for separating materials by liquid chromatography comprising passing said materials through a chromatographic column packed with the chromatographic support formed from porous glass or silica gel modified by a process comprising treating said porous support with a solution of a metal selected from the group consisting of aluminum, iron, zirconium, titanium, chromium, tin, lanthanum, rare earth, alkaline earth, zinc, hafnium, thorium and gallium to sorb said metal onto the porous support and separating said materials on passage of one or more mobile phases having a pH above about 7.5 or a temperature above about 35° C. through said chromatographic column.
Claim 2
Dependent Claim
102 words
A process for separating materials by liquid chromatography comprising passing said materials through a chromatographic column packed with the chromatographic support formed from porous glass or silica gel modified by a process comprising treating said porous support with a solution of a metal selected from the group consisting of aluminum, iron, zirconium, titanium, chromium, tin, lanthanum, rare earth, alkaline earth, zinc, hafnium, thorium and gallium to sorb said metal onto the porous support and separating said materials on passage of one or more mobile phases having a pH above about 7.5 or a temperature above about 35° C. through said chromatographic column.
Claim 3
Dependent Claim
28 words
The process of claim 1 wherein said materials are selected from the group consisting of amines, amino acids, purines, nucleosides, nucleotides, aminoglycosides, peptides, proteins, nucleic acids and enzymes.
Claim 4
Dependent Claim
22 words
The process of claim 1 wherein any of said one or more mobile phases has a pH of about 8 to 10.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1990-03-09 | 1990-09-08 | 1991-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-03-09 | 1994-09-08 | 1995-03-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-03-09 | 1998-09-08 | 1999-03-10 | $7700.00 | Window Closed / Lapsed |