Circular Dichroism (CD)

Purpose

Starna’s Circular Dichroism (CD) Certified Reference Materials (CRMs) are designed to qualify and verify the CD amplitude across the UV and visible range of wavelengths for CD spectrometers across their operational range, providing established, spectrum‑wide calibration points.

They are designed to support instrument performance and method verification along with routine quality assurance of CD spectrophotometers, across a wide range of analytical and applied spectroscopy applications.

Each set contains permanently flame‑sealed quartz cells with an aqueous solution of optically-active metal compound in the R,R and S,S enantiomers — spanning both the UV and visible regions (190–700 nm and 400–700 nm). A blank is also included.

Description and Discussion

Each cell contains an aqueous solution of a chiral metal–organic compound supplied as R, R and S, S enantiomers.

These liquid CD Reference Materials are supplied in sets of permanently flame‑sealed far‑UV quartz cells.

The permanent flame‑sealed format eliminates evaporation, contamination and preparation errors associated with in‑house dilute chiral solutions, which are prone to insolubility and concentration inconsistencies. This supports improved repeatability, inter‑laboratory comparability and long‑term monitoring of CD instrumentation.

Three sets are available to provide the CD amplitudes required for calibration across both the UV and Visible regions.

Each set includes a Blank, R, R enantiomer, and S, S enantiomer, supplied in the following formats:

RM‑CD/A/UV – two low‑molarity enantiomer solutions + Blank
RM‑CD/A/VIS – two high‑molarity enantiomer solutions + Blank
RM‑CD/A/UVVIS – both low and high molarity enantiomer solutions + Blank

All references are engraved and colour‑coded for quick identification of enantiomer type and molarity.

The materials are produced under ISO 17034 and certified under Starna’s ISO/IEC 17025 accreditation, ensuring traceable rotational values with associated U95 (95% confidence) uncertainties.

The Certificate of Calibration includes a selection of calibration values and corresponding U95 uncertainties for the location of maxima and minima in circular dichroism amplitude, according to wavelength.

Also provided with each set is a table of parameters, which may be used to generate the certified spectrum as a continuous function, together with upper and lower bounds that constitute the uncertainty envelope for that function.

Typical spectra

The Reference Materials show typical Blank‑corrected spectra, recorded for each type of enantiomer and molarity of solution. The spectra exhibit well‑defined peaks across the UV and Visible regions, reflecting the expected CD signature of the certified solutions.

Certified value points identify the spectral minima and maxima, for which certified values and the U95 uncertainties are provided on the certificate.

Note: Supplied spectra are provided for information only and are not intended to be used to derive reference values in any measurement procedure.

Circular Dichroism Certified Reference Materials (Visible region): RM‑CD/A/VIS

Circular Dichroism Certified Reference Materials (UV region): RM‑CD/A/UV

A combined reference kit, including CD Certified Reference Materials for both the UV and Visible regions, is available as RM‑CD/A/UVVIS.

Catalogue Number

Each set contains:

Blank, R, R enantiomer, S, S enantiomer

Reference	Catalogue Number
CD UV Reference Kit (Two low molarity concentrations of R, R enantiomer and S, S enantiomer and a Blank)	RM-CD/A/UV
CD Visible Reference Kit (Two high molarity concentrations of R, R enantiomer and S, S enantiomer and a Blank)	RM-CD/A/VIS
CD UV-Visible Reference Kit (Two low molarity and high concentrations of R, R enantiomer and S, S enantiomer and a Blank)	RM-CD/A/UVVIS

Product enquiry

Data sheet

Technique

UV-VIS References