Overview
This pilot study quantified residual palladium in 39 drug-like compounds following Suzuki-Miyaura, Buchwald-Hartwig, and nitro-reduction reactions with standard palladium catalysts and purification techniques. The majority of compounds met the ICH guideline limit of 100 ppm for oral drugs, but 5 out of 39 compounds exceeded 50 ppm, and all were below 100 ppm. The work informs pharmaceutical process chemistry approaches to minimizing Pd impurities.
Key numbers
- Residual Pd range: below LOQ to approximately 5000 ppm (depending on Pd source and purification)
- 5 out of 39 products exceeded 50 ppm Pd
- All 5 were below 100 ppm Pd
- ICH guideline limit for Pd in oral drugs: 100 ppm (10 ug/day at 10 mg/day dose)
- Nitro reduction with one specific Pd source: produced below-LOQ residuals
- 8 Pd catalyst sources tested (labeled i-viii) with multiple ligand/catalyst combinations
Methods (brief)
39 drug-like compounds synthesized via Pd-catalyzed reactions (Suzuki-Miyaura cross-coupling, Buchwald-Hartwig amination, and nitro-reduction). Standard purification techniques applied. Residual Pd quantified by ICP-MS or ICP-OES. Results compared against ICH Q3D elemental impurity guideline for oral drug products (100 ppm Pd).
Implications
This page makes the source discoverable for palladium evidence routing. Provides pharmaceutical process chemistry data on Pd impurity levels in drug compounds, relevant for understanding Pd exposure via oral medications synthesized with Pd catalysts and for contextualizing regulatory limits on Pd in drugs relative to food exposure.
Related evidence
Update history
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