Determination of Elemental Impurities in Carrier-free Lutetium Chloride ¹⁷⁷Lu Solution by ICP-MS

OBJECTIVE  To establish an inductively coupled plasma-mass spectrometry(ICP-MS) method for determining elemental impurities in domestically produced carrier-free lutetium chloride ¹⁷⁷Lu solution.

METHODS  With Sc, Y, In, and Bi used as internal standards, an ICP-MS method was developed and established with the following conditions: RF power of 1550 W, carrier gas flow rate of 0.8 L·min⁻¹, collision gas flow rate of 5.03 mL·min⁻¹, nebulization chamber temperature of 2.7 °C, sampling depth of 5 mm. The method was validated for key analytical parameters.

RESULTS  Each elements exhibited good linearity within the specified ranges(r>0.9990), the recovery rates at low, medium and high concentrations(n=9) were in 80%−118%. Three batches of carrier-free lutetium chloride ¹⁷⁷Lu solution samples were tested, the test results indicated that Class 1 elemental impurities specified in the ICH Q3D guidelines were not detected, trace amounts of Class 2A element Ni and Class 2B element Ir were detected.

CONCLUSION  The developed method demonstrates high sensitivity, good precision with good accuracy, making it suitable for quality control of elemental impurities in carrier-free lutetium chloride ¹⁷⁷Lu solution.