... %, 15%, 20%, 25%, 30%, 40%, 50%, 60%, 65%, 70%, 75%, 80%, 90% HPLC 3. EGCG 10%, 15%, 20%, 30 ... %, 35%, 40%, 45%, 50%, 55%, 60%, 70%, 80%, 90%, 95% HPLC 4. Caffeine 1%, 5%, 8 ... Catechins, EGCG, Caffeine. For example, Polyphenols 95%+Catechins 70%+EGCG 40%+Caffeine 5% Specification Sheet Product Name:Green ... 2ppmAssayPolyphenols by UV> 95.0%Catechins by HPLC> 70.0%EGCG by HPLC> 40.0%Caffeine by HPLC ...