Reference samples, called standards, are required to determine the concentration of chemical compounds using highly sensitive quantitative analytical procedures. These standards have a defined concentration of one or several known compounds. It goes without saying that the concentration(s) of these standards must be as accurate as possible to prevent subsequent errors in determining unknown concentrations in samples. Although preparation of standards of known concentration(s) is a common routine in analytical laboratories, two problems regularly confront lab technicians:
1. The required weight of the soluble compound(s) is calculated based on the volume and desired concentration of the solvent. The decisive problem is the weight of the solid compound(s). Normally, high-resolution laboratory balances with an accuracy of several decimal places are used to measure the exact weight. However, it is next to impossible to reach the target weight exactly during dosing of a compound.
2. If the compound weighed does not precisely equal the calculated weight, the volume of solvent has to be adjusted to reach the desired final concentration. Recalculation of the required volume of liquid takes time and is a possible source of error.
The Cubis® MSA dosing system with the YAPP16 Q-App software is precisely designed to eliminate these problems described. The system guides the user automatically throughout the entire process of preparing standards, and the application software automatically takes care of all calculations in the background. There is no need to reach the target weight exactly as the software automatically corrects the required solvent volume to the appropriate value. At the end of this procedure, the software uses the weight of the compound(s) measured and the gravimetrically checked, effective solvent weight to calculate the verified concentration(s) and the verified volume of the standard prepared.