Laser-based capillary polarimeter.

K Swinney; J Hankins; D J Bornhop

PubMed · 11315158

Laser-based capillary polarimeter.

Abstract

A laser-based capillary polarimeter has been configured to allow for the detection of optically active molecules in capillary tubes with a characteristic inner diameter of 250 microm and a 39-nL (10(-9)) sample volume. The simple optical configuration consists of a HeNe laser, polarizing optic, fused-silica capillary, and charge-coupled device (CCD) camera in communication with a laser beam analyzer. The capillary scale polarimeter is based on the interaction between a polarized laser beam and a capillary tube, which results in a 360 degree fan of scattered light. This array of scattered light contains a set of interference fringe, which respond in a reproducible manner to changes in solute optical activity. The polarimetric utility of the instrument will be demonstrated by the analysis of two optically active solutes, R-mandelic acid and D-glucose, in addition to the nonoptically active control, glycerol. The polarimetric response of the system is quantifiable with detection limits facilitating 1.7 x 10(-3) M or 68 x 10(-12) nmol (7 psi 10(-9) g) sensitivity.

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Calibration Electrophoresis, Capillary Equipment Design Glucose Lasers Mandelic Acids Polarography Sensitivity and Specificity Stereoisomerism Journal Article Research Support, Non-U.S. Gov't

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K Swinney, J Hankins, D J Bornhop. Laser-based capillary polarimeter.. https://pubmed.ncbi.nlm.nih.gov/11315158/

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