13C3-Caffeine, 100 µg/ml, Methanol, 1ml Back Catalog number: 681491 Manufacturer: HPC STANDARDS GmbH Availability: In the manufacturer's stock Price on request - + Recommended 92386 525.2 Internal & Surrogate Standard Price on request 675310 D4-Ethephon, 5mg Price on request 28013 EPA Method 8260B Purgeable Internal Standard Price on request