Chromium Picolinate

Chromium picolinate (chromium tripicolinate, CAS 14639-25-9) is a coordination complex in which one chromium(III) centre is chelated by three molecules of picolinic acid, pyridine-2-carboxylic acid. The molecular formula is C18H12CrN3O6, written in the USP monograph as C18H12N3O6Cr, with a molecular weight of 418.31 and a theoretical elemental chromium content of 12.4%. It is a reddish to dark red crystalline powder and is very sparingly soluble in cold water; the USP limit tests exploit this, dissolving the material in water heated to 70-90 degrees C and filtering off the precipitate that reforms on cooling. The USP monograph requires not less than 98.0% and not more than 102.0% of C18H12N3O6Cr calculated on the dried basis, assayed by atomic absorption spectrophotometry at the 357.9 nm chromium emission line against potassium dichromate standards. Identity is confirmed by infrared absorption and by the alkaline hydrogen peroxide colour test. Loss on drying is not more than 4.0% after four hours at 105 degrees C, chloride not more than 0.06% and sulphate not more than 0.2%. Chromium picolinate is also listed in Annex II of Directive 2002/46/EC, as amended by Commission Regulation (EU) No 1170/2009, as a permitted chromium source for food supplements. Chromium(III) is a trace element in human nutrition, and the picolinate is the form most commonly specified by supplement manufacturers because it is a stable, well-defined solid with a documented pharmacopoeial standard. Since typical inclusion is at microgram level per dose, Thovek supplies both a standard crystalline grade and a micronised grade, and can provide triturated premixes where content uniformity in direct-compression blends is the constraint. Batches are certified for assay, elemental chromium, loss on drying, chloride, sulphate, heavy metals and microbiology; testing to confirm the absence of hexavalent chromium is available on request. Export documentation includes CoA, MSDS, Certificate of Origin and allergen, GMO and BSE/TSE statements.