From the Desk of
Jason Fisher, Reference Standards Product Manager
Managing Unstable Reference Standards with Short Shelf Life—Let’s Use Acrolein as an Example…
Environmental labs are familiar with calibration issues and inventory management challenges with acrolein standards. Acrolein, as listed in EPA Method 8316 (SW-846), is an aldehyde with poor stability under analytical conditions. When acrolein (an aldehyde) is combined with methanol (an alcohol), the formation of acrolein dimethyl acetal (3,3-Dimethoxy-1-propene) occurs as the methanol adds to the carbonyl site of the acrolein. This reaction begins quickly—despite Restek manufacturing the standards under strict processing conditions; packaging them in flame-sealed, amber glass, deactivated ampuls; and blanketing them with nitrogen. The result is a maximum shelf life of three months.
Below are two solutions to consider for keeping your instruments calibrated with reliable standards:
Set Up a Standing Order
Unstable compounds with a short shelf life make management of your standards quite challenging. In the case of acrolein, if your methods mandate methanol-based calibration standards, you can reduce your administrative cost and calibration challenges by placing a standing order (sometimes called as a “blanket order”) with prescheduled deliveries of freshly made solutions. Restek manufactures and inventories two new independent batches of these standards monthly to help ensure you always have what you need, when you need it. Contact us to set up a standing order today.
Consider Alternative Formulations
Restek’s talented chemists are continuously researching methods of stabilizing compounds and formulating stable solutions. When working with notoriously unstable compounds, consider evaluating alternative formulations if your methods permit flexibility. Looking back to acrolein as an example, although method SW-846 states “methanol is used as the solvent,” labs are not required to use methanol calibration standards and you may be able to use CRMs in water. Our chemists have developed proprietary methods of stabilizing acrolein in water—achieving 18-month stability—to offer you an alternate way of relieving your challenges with methanol-based solutions.
Whether in Methanol or Water, the Acrolein Standards You Need are a Click Away
Regardless of your application, where to source your calibration standards is a crucial decision. You can rely on Restek as your trusted source of high-quality certified reference materials (CRMs). Learn more about Restek’s reference standards operations and browse our online catalog at