US4372850A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reverse-phase thin layer chromatographic plate
Assignee: Shionogi and Co Ltd
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Filing: 1981-04-09
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Granted: 1983-02-08
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Expires: 2001-04-09
Abstract
Abstract The conventional water-resistant silica or alumina plate for thin layer chromatography is converted into a reverse-phase thin layer chromatographic plate by tri-(lower alkyl)silylating the adsorbent in situ. The adsorbent layer containing the tri-(lower alkyl)silyloxy group is found to be superior to either of the known adsorbent layers containing mono- or di-(lower alkyl)silyloxy groups, or mono-(higher alkyl)silyloxy groups. Optimum conditions for performing a method for preparing the plate are also disclosed.
Inventors
- 👤 Tamotsu Okumura
- 👤 Tetsuro Kadono
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 13:27
CPC Classifications
G; G01; G01N; G01N30/00; G01N30/02; G01N30/50; G01N30/52; B; B01; B01J; B01J20/00; B01J20/02; B01J20/06; B01J20/08; B01J20/10; B01J20/103; B01J20/28; B01J20/28014; B01J20/2803; B01J20/281; B01J20/286; B01J20/287; B01J20/30; B01J20/3042; B01J20/32; B01J20/3202; B01J20/3204; B01J20/3231; B01J20/3242; B01J20/3244; B01J20/3246; G01N30/90; G01N30/92; G01N30/93; B01J2220/00; B01J2220/40; B01J2220/42; B01J2220/49; B01J2220/50; B01J2220/54
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
33 words
A water-resistant thin layer chromatographic plate for reverse-phase thin layer chromatography, comprising: a base plate and a silica or alumina adsorbent wherein 10-40% of the hydroxyl groups of said adsorbent are tri-(lower alkyl)silylated.
Claim 2
Dependent Claim
33 words
A water-resistant thin layer chromatographic plate for reverse-phase thin layer chromatography, comprising: a base plate and a silica or alumina adsorbent wherein 10-40% of the hydroxyl groups of said adsorbent are tri-(lower alkyl)silylated.
Claim 3
Dependent Claim
16 words
The chromatographic plate according to claim 1, wherein 15-30% of said hydroxyl groups are tri(lower alkyl)-silylated.
Claim 4
Dependent Claim
17 words
The chromatographic plate according to claim 1, wherein approximately 23% of said hydroxyl groups are tri(lower alkyl)silylated.
Claim 5
Dependent Claim
13 words
The chromatographic plate according to claim 1, wherein said hydroxyl groups are trimethylsilylated.
Claim 6
Dependent Claim
16 words
The chromatographic plate according to claim 1 or 4, which further includes an acid-resistant fluorescent material.
Claim 7
Dependent Claim
35 words
A water-resistant thin layer chromatographic plate for reverse-phase thin layer chromatography, consisting essentially of: a base plate and a silica or alumina adsorbent wherein 10-40% of the hydroxyl groups of said adsorbent are tri-(lower alkyl)silylated.
Claim 8
Dependent Claim
35 words
A water-resistant thin layer chromatographic plate for reverse-phase thin layer chromatography, consisting essentially of: a base plate and a silica or alumina adsorbent wherein 10-40% of the hydroxyl groups of said adsorbent are tri-(lower alkyl)silylated.
Claim 9
Dependent Claim
13 words
The chromatographic plate according to claim 6, wherein said hydroxyl groups are trimethylsilylated.
Claim 10
Independent Claim
52 words
A method for preparing a water-resistant reverse-phase thin layer chromatographic plate, comprising the steps of: contacting a silica or alumina adsorbent which has been previously coated on a base plate with a tri-(lower alkyl)-silylating agent under conditions sufficient to replace 10-40% of the hydroxyl groups of said adsorbent with tri-(lower alkyl)-silyloxy groups.
Claim 11
Independent Claim
52 words
A method for preparing a water-resistant reverse-phase thin layer chromatographic plate, comprising the steps of: contacting a silica or alumina adsorbent which has been previously coated on a base plate with a tri-(lower alkyl)-silylating agent under conditions sufficient to replace 10-40% of the hydroxyl groups of said adsorbent with tri-(lower alkyl)-silyloxy groups.
Claim 12
Dependent Claim
18 words
The method according to claim 8, wherein 15-30% of said hydroxyl groups are replaced by tri-(lower alkyl)-silyloxy groups.
Claim 13
Dependent Claim
19 words
The method according to claim 8, wherein approximately 23% of said hydroxyl groups are replaced by tri-(lower alkyl)silyloxy groups.
Claim 14
Dependent Claim
36 words
The method according to claim 8, wherein said base plate is soaked in a 0.1 to 10 w/v% solution of an alkylsilylating agent in an organic solvent under atmospheric pressure at 10°-30° C. for 10-60 minutes.
Claim 15
Dependent Claim
40 words
The method according to claim 8, wherein said base plate is soaked in a 0.1 to 10 w/v% solution of an alkylsilylating agent in an organic solvent under a pressure of about 30 Torr at 10°-30° C. for 10-60 minutes.
Claim 16
Dependent Claim
15 words
The method according to claim 8, wherein said tri-(lower alkyl)silylating agent is a tri-(lower alkyl)-chlorosilane.
Claim 17
Dependent Claim
13 words
The method according to claim 8, wherein said tri-(lower alkyl)silylating agent is trimethylchlorosilane.
References Cited (Backward Citations)
US4295968A
Cited
US4298500A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-02-07 | 1986-08-09 | 1987-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-07 | 1990-08-09 | 1991-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-07 | 1994-08-09 | 1995-02-08 | $7700.00 | Window Closed / Lapsed |