主题：【求助】近红外能否检测比旋度指标？

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近红外能否检测比旋度指标？

糖是具有旋光活性的化合物，旋光分析（简称旋光法）是利用直线偏振光，通过含有光学活性化合物的液体或溶液时引起旋光现象，使通过的偏振光平面向左或向右旋转，因此，在一定条件下，检测偏振光旋转的方向和度数，可以区别某些化合物的旋光性，或检测化合物的杂质、纯度和含量。

物质的旋光度大小与下列因素有关：一是物质的旋光度与温度有关。有的物质随着温度升高旋光度增加，如石英等，有的物质随着温度升高而旋光度减少，如蔗糖等，因此在测试时，必须准确掌握温度，然后进行修正。二是物质的旋光度与平面偏振光的波长λ有关，波长不同，旋光度也不一样。三是物质的旋光度与旋光物质有关，不同的旋光物质有不同的旋光度。

手头资料有限，不知道用近红外仪器能否检测比旋度这个指标？

希望有这方面经验的专家给点建议

推荐答案：sfye回复于2007/11/25

直接测应该不行，可以参考附件的文献
http://pubs.acs.org/cgi-bin/abstract.cgi/ancham/2003/75/i23/abs/ac034684f.html

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斑竹：本文件已丢失，无法验证。
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Anal. Chem., 75 (23), 6455 -6462, 2003. 10.1021/ac034684f S0003-2700(03)04684-5
Web Release Date: October 17, 2003

Copyright © 2003 American Chemical Society
Determination of Enantiomeric Compositions of Amino Acids by Near-Infrared Spectrometry through Complexation with Carbohydrate

Chieu D. Tran,* Victor I. Grishko, and Daniel Oliveira

Department of Chemistry, Marquette University, P.O. Box 1881, Milwaukee, Wisconsin 53201

Received for review June 24, 2003. Accepted September 10, 2003.

Abstract:

A new method has been developed for the determination of enantiomeric compositions of a variety of compounds. The method is based on the use of the near-infrared technique to measure diastereomeric interactions between an added carbohydrate compound with both enantiomeric forms of an analyte followed by partial least-squares analysis of the data. The fact that the method works well with all three macrocyclic carbohydrates with different cavity size (i.e., -, -, and -cyclodextrin) as well as with sucrose, which is a linear carbohydrate, clearly demonstrates that it is not necessary to have inclusion complex formation in order to produce effective diastereomeric interactions. Rather, a simple adsorption of the analyte onto a carbohydrate is sufficient. Since inclusion complex formation is not a requisite, this method is not limited to the amino acid studies here but is rather universal and sensitive as it can, in principle, be used to determine enantiomeric compositions for all types of compounds with only microgram concentration and enantiomeric excess as low as 1.5%, in water or in a mixture of water and organic solvent. Furthermore, it does not rely on the use of rather expensive carbohydrates such as cyclodextrins but is equally as effective even with a simple and inexpensive carbohydrate such as sucrose

补充答案：

fzy回复于2007/11/26

从理论上应该是可以的。只是操作起来可能会比较麻烦。我这边也准备扩展近红外的功能测残溶。你可以咨询你的仪器供应商，向他们寻求技术援助！供参考！

闲鹤野云回复于2007/12/07

每种物品的旋光度不同，能够以间接方法测定某种物质的旋光度，并不代表一定可以测定另外一种物质的旋光度，欢迎大家讨论。

jxdwdeng回复于2007/12/06

OK.十九楼的观点我不同意。这里讨论的旋光度可测否，葡萄糖只是个代表性的例子。如果测葡萄糖含量，根本没有计论的必要，地球人都知道，只要含量不是太小就可以测。

wcx972回复于2007/11/23

尝试过用近红外测含量和水,但没有做过比旋度