Liquid crystal quantitative analysis method for optically active compounds
US4011046A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 12, 1975 |
| Grant date | Mar 8, 1977 |
| Priority date | — |
| Expiry date | Nov 12, 1995 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T436/173845
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Using a standardized cell containing a thin layer of an aligned nematic liquid crystalline material, a relationship is determined between concentration of an optically active solute material in the liquid crystal layer and line spacing in a pattern produced by differential light refraction, upon the injection of different amounts of the optically active compound. Subsequently, quantitative analysis of a sample containing the optically active compound is accomplished by injecting a known amount of the sample into a second identical standardized cell, observing the line spacing of refracted light in the second cell and comparing it to the relationship determined in the first cell. Optically active compounds analyzable in this manner include steroids and cholesteryl esters. A preferred nematic liquid crystalline material is n-p-methoxybenzylidene-p-n-butylaniline. A specific system described consists of cholesteryl-2-methyl valerate in homeotropically aligned n-p-methoxybenzylidene-p-n butylaniline with a layer thickness in the cell of 12.7 microns.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.