Successful Achievement of Ultra Low Injector Carryover of Benzyl Alcohol Using Arc HPLC

Benzyl alcohol is known to give injector carryover in HPLC systems, which may result in out-of-specification values and, eventually, in-batch failure. In this experiment, we used the same HPLC method on the Waters Arc HPLC System and a comparable competitive HPLC system. The percentage carryover observed with the Arc HPLC System is much lower in comparison to the competitive system. The experiment confirms that the Arc HPLC System can minimize the injector carryover issue for benzyl alcohol.

Benefits

• The Arc HPLC System with Flow-Through Needle (FTN) design successfully reduces the carryover of an analyte

“Carryover" is a term used to describe a type of sample contamination, which causes sample peaks to reappear in later runs that do not actually contain the sample (e.g., blank runs). There are several factors that can influence injector carryover, including analyte chemical nature, column chemistry, and HPLC system injector design. 

The Arc HPLC System is a new High Performance Liquid Chromatography (HPLC) System used for routine testing in the pharmaceutical, food, academic, and various other markets. The Arc HPLC System is for laboratories looking for a rugged, reliable, and modern HPLC system that can run established HPLC methods regardless of the brand of liquid chromatograph on which they were originally developed, while preserving the chromatographic retention time reproducibility of those methods. The system offers ultra-low analyte carryover, superb injection precision, and backpressure tolerance to 9500 psi at 5.0 mL/min.

The experiment conducted here helps to minimize the carryover issue of benzyl alcohol. Benzyl alcohol is used in atropine injection as a preservative. The content of benzyl alcohol is typically (20x) higher than atropine sulfate. The single injection analysis poses the challenge of very high concentration of benzyl alcohol being injected on column.

The experiment was designed to investigate the injector carryover of benzyl alcohol in the post-sample blank injection. The same analytical method conditions where used on the Arc HPLC System and a comparable competitive HPLC system. The sample sequence contains a pre-sample blank, sample (80 µg/mL of atropine sulphate and 1800 µg/mL of benzyl alcohol), and post-sample blank.

The advanced Flow-Through Needle design of the Arc HPLC System helps to minimize the injector carryover, as the interior of the sample injection needle is continuously washed during the run. Further user-configurable wash settings provide the capability to address even ‘sticky’ compounds to ensure the successful management of injector carryover.

• The Arc HPLC System successfully achieved ultra-low injector carryover for benzyl alcohol analysis in atropine injection
• Injector carryover percentage is reduced 5.3x in the Arc HPLC System when compared with a competitive HPLC system
• The experiment confirms that the Arc HPLC System helps minimize the injector carryover issue for benzyl alcohol

1. Dlugasch, A., et al. Alliance Carryover Performance Part 1: Carryover Improvement Achieved Through Instrument Design Changes for the Alliance HPLC System. Waters Application Note, 2018, 720006386EN.