Analysis of Oils Part 4: Correcting the Boron Drop-out Phenomenon
As we discussed out in our last post, the length of environmental exposure and relative humidity levels have an impact on boron “drop-out” in working level standards. The longer the standards are exposed, and the higher the humidity in the air, the more boron is lost.
As part of VHG™’s continuing efforts to #GoBeyondTheStandard, we started work to develop a new boron starting material that would be inert to humidity. Our research and development team spent countless hours testing new formulations, to ensure that laboratories could continue their existing practice of leaving prepared samples open. The testing was successful and we launched our Advanced H•I Boron, which replaced the conventional boron starting material in all our single & multi-element standards. As you can see in Figure 2 as compared to Figure 5 below, use of the new VHG Advanced H•I Boron drastically improved boron recovery even after six days of being exposed to humid conditions.
Boron recovery improved from 33% to 88% after six days exposed to humid conditions in kerosene. While this was a huge improvement, we chose to go one step further and evaluated the stability under these same conditions when samples were prepared with the VHG V-Solv™ ICP Solvent (a proprietary low-odour, low-toxicity solvent, formulated to provide better stability than bulk commercial solvents).
In Figure 7 below, you can see that after six days of the sample being exposed to the same humid conditions, the boron recovery is still 100%. The VHG V21 blend using H•I Boron exhibited essentially no signal reduction, as opposed to when using xylene and kerosene as solvents. Slightly higher recoveries are even noticeable in other elements when switching from xylene and kerosene to V-Solv. With V-Solv as the diluent solvent for the stock standard, problems with rapid loss or even low recovery of boron were absent (< +/- 4%).
Conclusion
Using VHG H•I Boron in conjunction with V-Solv ICP Solvent as the diluent corrects stability issues commonly seen with boron and other elements, including silver, molybdenum, lead and vanadium.
If you want to explore the results of our study in more detail, please download our full Analysis of Oils: Understanding Chemical Stability & ICP Matrix Effects technical paper, which goes into our testing and outcomes in more depth. You can also visit our webshop to view the entire VHG portfolio of wear metal standards, which is constantly evolving as we seek to address issues and needs we hear about from the industry, boron drop-out being only the latest example.