Raman optical activity instrument for biochemical studies

Abstract

Abstract A simple and fully computer‐controlled backscattering incident circular polarization Raman optical activity (ICP ROA) instrument suitable for chioptic studies of biologically significant molecules in aqueous solution is described. It consists of a fast single‐stage monochromator equipped with a holographic edge filter, a highly efficient holographic difiaction grating and a thinned back illuminated thermoelectrically cooled charge‐coupled device detector as the key spectral elements. A longitudinal electro‐optic modulator is employed to switch between orthogonal circular polarization states in the incident laser radiation within a backscattering geometry. A thick Lyot depolarizer is used for the depolarization of the backscattered Raman radiation. High‐quality backscattering ICP ROA spectra of (1 S )‐( − )‐ trans ‐pinane, (1 R )‐( + )‐ trans ‐pinane, L ‐alanine, L ‐alanyl‐ L ‐alanine, lysozyme, D ‐glucose, α‐ D ‐cyclodextrin and 2′‐deoxycytidine are presented as typical examples of the excellent performance characteristics.