A device for reducing the atmosphere-induced interferences for analysis using inductively coupled plasma-mass spectrometry†
Abstract
The atmosphere-induced interference reduction device (AIRD) shows promise in mitigating interferences in inductively coupled plasma-mass spectrometry (ICP-MS) analysis. The effectiveness of AIRD in reducing interferences caused by atmospheric gases such as H, C, N and O was evaluated by using argon (Ar) and helium (He) as shielding gases due to their inert properties. Krypton (82Kr) served as an internal standard for monitoring and correcting instrumental sensitivity drift. The shielding gas flow rate was optimized using gas dynamics simulations, revealing a threshold of 10 L min−1 for optimal interference reduction. Results indicate the superiority of He in reducing interferences, with a reduction of 32% for 12C+, 51% for 15N+, 56% for 16O+, 54% for 16O1H1H+, 51% for 40Ar14N+, and 42% for 40Ar16O+ compared to Ar. Moreover, AIRD maintained low oxide yields even after shielding gas cessation, with oxide yield maintained at approximately 0.03% for 24 hours. Analyses of LA-ICP-MS coupled with AIRD demonstrate that ThO/Th can be reduced from 0.92% to 0.15% compared to normal analysis without AIRD. Experimental investigations further revealed that AIRD influenced elemental sensitivity, particularly with He as the shielding gas, with an ∼25.7% enhancement observed in the signal intensity of 82Kr.