Ultratrace Tin Speciation with GC-ICP-MS using the Thermo Scientific GCI 100 Interface

Significance of the Topic

Environmental impact and toxicity of tin species vary by chemical form, necessitating sensitive speciation analyses.

Objectives and Study Overview

The goal was to develop a robust and accurate GC-ICP-MS method for organotin speciation in water, integrating the Thermo Scientific TRACE 1310 GC with the iCAP RQ ICP-MS via the GCI 100 Interface.

Methodology and Instrumentation

• Instrumentation setup: TRACE 1310 GC with TriPlus RSH autosampler, GCI 100 transfer interface, and iCAP RQ ICP-MS controlled through Qtegra ISDS Software with ChromControl plug-in.
• GC conditions: splitless 1 µL injection at 300 °C, oven from 60 °C (1 min) ramped to 300 °C at 50 °C/min, hold 9.2 min; He carrier; TG 5MS column (30 m × 0.25 mm × 0.25 µm).
• ICP-MS settings: RF power 1550 W, sapphire injector, quartz torch, Pt-tipped sampler/skimmer, transfer line at 300 °C, Ar at 0.9 L/min; dwell time 10 ms on 118Sn and 120Sn.
• Sample preparation: organotin standards (TBT, TPT, TPhT) in 1 % HCl, ethylation with sodium tetraethylborate in hexane, hexane extract injected.
• Data acquisition: automated sequence of calibration standards and blanks over 10 h unattended operation.

Key Results and Discussion

Baseline separation with Gaussian peaks was achieved; no smoothing was required. Calibration over 0.02–10 ng/mL showed linearity > 0.999 and residuals < 2 %. LODs (3×SD of lowest standard) were 0.33 ng/L (TBT), 0.28 ng/L (TPT), 0.38 ng/L (TPhT), ~4–5× below EWFD MAC. Automated ICIS peak integration ensured reproducibility.

Benefits and Practical Applications

• Ultra-trace detection of organotin at pg–ng levels supports environmental monitoring.
• Reproducible, baseline-resolved speciation ideal for regulatory compliance.
• Fully integrated hardware–software workflow enhances throughput and reliability.
• One-sequence control simplifies routine labs for high-volume analysis.

Future Trends and Potential Applications

Further improvements could include advanced pre-concentration strategies, miniaturized interfaces, expanded speciation of other metal organics, and coupling with alternative chromatographic techniques to address broader environmental and industrial challenges.

Conclusion

The GCI 100 Interface seamlessly couples the TRACE 1310 GC and iCAP RQ ICP-MS, delivering a highly sensitive, automated, and reproducible solution for ultratrace organotin speciation in water, meeting strict regulatory standards.

Reference

• European Water Framework Directive; http://www.cuwcd.com/
• ICH Q2(R1): Validation of Analytical Procedures