New Method for Ultra-Trace Se, As, and Cr in Seawater
Brooks Applied Labs recently unveiled a new method for the quantitation of selenium, arsenic, and chromium in saline waters at concentrations of 5 ng/L (that converts to 0.005 µg/L!). This new capacity to support ultra-trace detection limits for elements predominately existing as anions in saline waters (such as seawater, brackish waters, and brines) will allow our clients and the scientific community to definitively support discharge requirements and investigations for estuaries, bays, near shore and open ocean, and saline lakes. Historically, these detection limits could only be achieved by using complicated and laborious preparatory methods that have a high degree of uncertainty and rely heavily upon reaction chemistry. With this new capability to support both low-level anionic and cationic metal analyses in some of the most difficult aquatic matrices, Brooks Applied Labs is setting what is expected to be the new gold standard for analytical laboratories around the world.
Methods for the analysis ultra-trace level metals in waters with high total dissolved solids (TDS) have traditionally been segregated into two groups: those applicable to elements that are present as cations or anions in solution. Preparatory methods designed to separate the target metals from alkali earth elements (Na, K, Mg, and Ca) and their conjunctive halogen anions (chloride, bromide, sulfate) often use precipitation techniques which involve reaction chemistry. As with any chemical reaction there are constants associated the reaction efficiencies and equilibriums. Those constants can change, depending on the complexity of the sample matrix and chemical reaction, which necessitate the use of assumptions. The evolution of technology has yielded methods which use automated in-line pre-concentration techniques (column chelation) for cationic transition metals but failed to support metals present as anions, until now.
Independent research at Brooks Applied Labs has produced an automated in-line pre-concentration method which separates the anionic metals from interfering salts. The method has undergone validation confirming the support for all prevalent molecular forms of selenium, arsenic, and chromium in natural aquatic systems to eliminate assumptions regarding method performance. The inherent benefits to automated in-line pre-concentration techniques equates to fewer re-analyses, fewer assumptions, superior accuracy and precision, all at a reduced cost compared to bench scale preparation techniques.
The new analytical method Brooks Applied Labs is offering is another testament to our devotion to science, our level of understanding about how our results are applied, as well as our desire to meet the data objectives of our clients. Contact us today to identify how partnering with Brooks Applied Labs can help you meet your current and future analytical needs for regulatory compliance, ecological modeling, and other investigations associated with selenium, arsenic, and chromium.