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Paracetamol ≥99% — chemical reagent for laboratory, research and analytical use. Not for human or animal consumption.
Chemical reagent intended solely for laboratory, research and analytical purposes. NOT FOR CONSUMPTION by humans or animals. It is not a medicinal product, dietary supplement or foodstuff.
Caffeine is a purine alkaloid of the methylxanthine group, formally 1,3,7-trimethyl-3,7-dihydro-1H-purine-2,6-dione. Its molecule is built on a bicyclic purine framework in which three nitrogen atoms bear methyl groups, and the system contains two carbonyl groups. Caffeine is among the best-characterised organic compounds, with well-documented spectral, thermal and chromatographic properties, which makes it one of the most frequently used analytical standards in laboratories.
The supplied material is a white, odourless crystalline powder with a bitter taste and high declared purity. Owing to its reproducible physicochemical properties and stability under normal conditions, caffeine is a convenient and inexpensive reference substance used in quality control and in analytical chemistry teaching.
| Systematic name (IUPAC) | 1,3,7-trimethyl-3,7-dihydro-1H-purine-2,6-dione |
| Synonyms | caffeine, theine, guaranine, 1,3,7-trimethylxanthine |
| CAS number | 58-08-2 |
| Molecular formula | C8H10N4O2 |
| Molar mass | 194.19 g/mol |
| Appearance | white, odourless crystalline powder |
| Solubility | moderately soluble in water (better in hot water); soluble in chloroform |
| Melting point | approx. 235 °C (with sublimation) |
| Purity | ≥99% |
Caffeine is one of the most popular standards in analytical chemistry. In UV spectrophotometry it shows a characteristic absorption maximum around 273 nm, which makes it a frequent calibration standard in quantitative assay methods. In liquid chromatography (HPLC) and thin-layer chromatography (TLC), caffeine is used as a retention marker and as a standard for method validation and for checking the reproducibility of separation systems.
In quality-control laboratories, caffeine serves as a reference substance when determining its content in food, beverage and plant-material samples by instrumental methods. It is also a model analyte in educational work illustrating the extraction, crystallisation and sublimation of organic compounds, and its well-known thermal properties make it a useful standard in thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). All applications are strictly research and analytical in nature. The product should be stored in a dry place, in a tightly closed container, away from moisture. The material is not intended for consumption or for any use on living organisms.