An ICP-MS system will operate and deliver numerical data even if not set up correctly or operating at expected levels. As discussed in a previous blog, Improve your ICP-OES Performance by using an Internal Standard, internal standards can be used to compensate for a variety of factors that degrade analytical performance, however, proper instrument set-up is core to data integrity. As a result, tuning of ICP-MS instruments is considered by most users to be a daily, if not more frequent, activity, and a prerequisite for achieving accurate results. Best practices dictate, and many standard methods require, that a sample sequence begin with an optimization block, during which a tuning solution is used to set-up the instrument.
The tuning process can differ between types of systems and applications, however, the fundamental principle and practices are the same. The array of actions that make up tuning are currently executed with software-driven “autotuning” procedures. Autotuning adjusts the instrument’s lens voltages, flowrates, ICP electronics and quadrupole voltages accordingly to achieve performance specifications developed per the instrument model. Solutions used for tuning (or optimization) of the system are commonly called “tuning” or “tune-solutions” and are typically delivered as low concentration (1 to 10 μg/L) solutions. In nearly every case they will have elements at low mass (<20 amu), mid-mass (89-115 amu) and high-mass (>200 amu) in order to fully optimize and validate the entire mass range of the instrument. It is important that the tune solution not have impurity elements since many of the actions performed involve the measurement of background masses or neighboring masses of the analytes. If an incorrect solution or one with impurities is utilized, it can result in severe de-optimization of the instrument.
Current ICP-MS configurations have a vast range of modes for cell gas, cool plasma, flow injection, etc.; as a result, there is not always a “one size fits all” choice for a tuning solution standard. Check out our high-quality, pre-configured tuning solutions, designed to match instrument manufacturer’s specifications below.