Patent US4025392A successfully refreshed from Google Patents.
US4025392A
Expired / Lapsed
US
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Chromogenic substrate for determination of amylase activity
Assignee: United States Department of Agriculture
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Filing: 1976-04-14
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Granted: 1977-05-24
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Expires: 1996-04-14
Abstract
Abstract An improved chromogenic substrate for alpha -amylase assays is synthesized by reacting amylose with Cibachron Blue F3GA, sodium sulfate and trisodium phosphate and incubating the resultant dyed amylose substrate with a buffer containing calcium chloride. The new substrate is more sensitive than commercially available chromogenic substrates in determining the alpha -amylase activity of the enzymes of sweet potato, tobacco, and human saliva.
Inventors
- 👤 Therese Marie Dougherty
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:57
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/34; C12Q1/40
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
97 words
In a process for preparing a chromogenic substrate product for the determination of amylase activity wherein amylose is reacted with Cibachron Blue F3GA, sodium sulfate and trisodium phosphate and the resulting dyed amylose substrate washed and dried, the steps for obtaining an improved highly sensitive substrate product having especial efficacy for determining α-amylase activity in plant and other very dilute enzyme extracts, comprising incubating the substrate obtained by the aforesaid reaction at about 44° C. in a 0.04M phosphate buffer containing 0.001M calcium chloride, washing the incubated with water until practically colorless, and freeze-drying the washed product.
Claim 2
Dependent Claim
97 words
In a process for preparing a chromogenic substrate product for the determination of amylase activity wherein amylose is reacted with Cibachron Blue F3GA, sodium sulfate and trisodium phosphate and the resulting dyed amylose substrate washed and dried, the steps for obtaining an improved highly sensitive substrate product having especial efficacy for determining α-amylase activity in plant and other very dilute enzyme extracts, comprising incubating the substrate obtained by the aforesaid reaction at about 44° C. in a 0.04M phosphate buffer containing 0.001M calcium chloride, washing the incubated with water until practically colorless, and freeze-drying the washed product.
Claim 3
Dependent Claim
19 words
An improved chromogenic substrate for the determination of amylase activity comprising the product of the process of claim 1.
References Cited (Backward Citations)
US3679661A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-05-23 | 1980-11-22 | 1981-05-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-23 | 1984-11-22 | 1985-05-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-23 | 1988-11-22 | 1989-05-24 | $7700.00 | Window Closed / Lapsed |