The Waters Acquity Uplc System 5-Fold Improvement In Lc/Ms Run Times Triple Food Testing Labs

BACKGROUND

The confirmatory unit of a UK-based analytical laboratory tests domestically-grown poultry and livestock as well as imported food of animal origin for banned substances and residues of legal veterinary drugs. The lab admits approximately 35,000 samples annually.

EU legislation dictates the identification criteria for confirming the presence of a veterinary drug residue, including the number of transition ions that must be monitored along with tolerances for acceptable ion ratios. The lab presently uses a mix of traditional HPLC instruments configured with a variety of Waters? MS Technologies mass spectrometers.

CHALLENGE

As a confirmatory laboratory, speed, sensitivity and accuracy are important. The average run time for an HPLC/MS confirmatory method is about 25 minutes. Despite the relatively small number of samples it tests in each batch, the lab must analyze up to 20 standards and quality assurance (QA) samples to confirm the presence or absence of a certain drug. In total, it can take between seven and nine hours to obtain one analytical result. Performing all the requisite QA tests consumes valuable instrument time and makes scheduling difficult and inefficient. Waters, Micromass, ACQUITY UPLC, ACQUITY Ultra Performance LC, UPLC, and Quattro Premier

The lab also performs surveillance testing. When the lab suspects that a farmer is using veterinary drugs improperly, it has the authority to detain a shipment of marketable product until the tests have been completed. For these samples, results must be delivered within five days. If a test takes more than five days, and the results come back negative—and the carcass spoils—the grower can sue
the laboratory for economic damages. If the lab knows it won’t meet the deadline, it has no recourse but to release the shipment and allow potential health risks into the food supply.

SOLUTION

In 2005, the lab acquired a Waters® ACQUITY Ultra Performance LC® (UPLC®) System that was installed on the front end of a Waters Quattro Premier™ XE tandem quadrupole mass spectrometer. The lab manager said it took him about three hours to transfer the 24-minute nitrofuran HPLC separation to a 4.5-minute UPLC separation—one that he says gives him “much better resolution.” The speed of the UPLC System combined with the Quattro Premier XE’s exceptionally fast scanning and rapid switching between ionization modes allows the lab to complete runs in less time—and to expand the scope of its multi-residue testing by being able to detect a much larger number of drugs per analytical run.

BUSINESS BENEFIT

The laboratory took a 25-minute LC/MS run down to four to five minutes, a five-fold improvement in overall run time. The lab manager can now schedule two or three batches of samples in an eight-hour period—tripling the lab’s output.

Probably the largest benefit is in methods development. In developing any HPLC method, a typical reversed-phase HPLC gradient method tends to take anywhere from 25 to 30 minutes. “If UPLC runs are four to five minutes, essentially you don’t have time for a cup of tea before you know whether your run worked or not and you are ready to do your next injection. At least with UPLC, you know very quickly. What we’ve found is that methods development is much more rapid with UPLC than with traditional HPLC,” the lab manager says.