August 2010, Sunnyvale, CA—Dionex announces two sample-preparation methods for determination of sialic acids in infant formulas; both methods remove many potentially interfering compounds and offer the advantage of direct analysis without sample derivatization. Application Note 253: HPAE-PAD Determination of Infant Formula Sialic Acids demonstrates accurate determination by high-performance anion-exchange with pulsed amperometric detection (HPAE-PAD) using the Dionex CarboPac^® PA20 column following acid hydrolysis and maltodextrin removal using one of two sample-preparation methods.

Dietary sialic acids are important for infant development; however, unfortified infant formulas made from bovine milk have a lower sialic acid content than human milk. Therefore, manufacturers have begun enriching infant formulas with sialic acids to more closely mimic human milk. Of the many existing methods for determination of sialic acids in a complex matrix, chromatographic methods often require further sample derivatization for analyte detection, whereas other approaches are hampered by interferences. In contrast, both new methods are specific and direct, providing reliable determination of sialic acids in acid-hydrolyzed infant formula samples without sample derivatization.

Dionex (NASDAQ:DNEX) is a global leader in the manufacturing and marketing of liquid chromatography and sample preparation systems, consumables, and software for chemical analysis. The company's systems are used worldwide in environmental analysis and by the life sciences, chemical, petrochemical, food and beverage, power generation, and electronics industries. Our expertise in applications and instrumentation helps analytical scientists to evaluate and develop pharmaceuticals, establish environmental regulations, and produce better industrial products.

CarboPac is a registered trademark of Dionex Corporation.