ST-ANDard Isotopic Labelling



e-mail npb@st-and.ac.uk, Phone +44 (0)1334 463856

University of St Andrews, School of Chemistry, Fife. KY16 9ST. UK

Manufacturer and supplier of benign labelled natural products for nutraceutical, medicinal and veterinary analysis.

Our products

Our products incorporate three or more benign heavy isotopes consisting 2H, 13C or 15N or a mixture of these which are precisely built in by total synthesis. All are incorporated into the skeleton of the molecule on sites where they are not prone to exchange. Once added to a mixture, the standards ratio will always remain the same with respect to that of the chemical under analysis. Since this ratio will always remain intact, whatever losses occur on processing prior to and during analysis will not change the result, unless they destroy the chemical completely. Even in this case, the lack of the standard will tell you something is wrong!

The natural abundance of heavy isotopes could affect accuracy of measurement. For example 13C is available in nature in about a 1:99 ratio so this would always affect the accuracy of singly labelled standards. By the time we incorporate three labels this inaccuracy becomes negligible for small molecules. Our standards are designed to display one distinct signal in linear relation to the natural materials abundance for a simple and accurate identification by mass spectrometry. To be sure of the presence and quantity of many of the beneficial chemicals in foods and other mixtures our standards are the best available.

NMR of liquids and solids

Estradiol (above) may be mimicked by daidzein, a phytoestrogen. Our daidzien contains three 13C atoms (*)

The isotopic labelling solution

Beyond our list of currently available chemicals we have much more to offer. We can undertake rapid synthesis of modified materials and would welcome contract development of novel standards. Our range is under constant change. We are proud to have formed a collaboration with IsoLife of the Netherlands and recommend their products for a range of work where universally labelled standards offer the best solution. Please contact us and we will help you find the best labelled chemicals for your needs.