Abstract: This study aims to establish the HPLC fingerprints of Single decoction,Single decoction mixture and combined decoctions of Lonicerae similis Flos and Radix scrophulariae crude drugs,investigating changes that the fingerprints and the content of the index constituents for the liquids mixed by different methods.The separation was performed on SHIMADZU Inert Sustain C₁₈ column (250 mm×4.6 mm,5 μm) with mobile phase composed of acetonitrile-0.2% phosphoric acid solution (gradient elution) at the flow rate of 1.0 mL/min,The column temperature was set at 30  ℃ and the detection wavelength was set at 210,240,235,236,325,327 and 280 nm;The experiment respectively set up the fingerprints of 10 batches of Single decoction,Single decoction mixture and combined decoctions of Lonicerae similis Flos and Radix scrophulariae crude drugs,demarcate common peaks and gain reference fingerprint.Attributing analysis the common peak of the fingerprint and determining the content of index ingredients through the 11 kinds of mixed control in the liquids mixed by different methods.As a result,24 co-possessing peaks were marked in the HPLC fingerprints of single decoction of Lonicerae similis Flos by taking chlorogenic acid peak as the reference peak,11 co-possessing peaks were marked in the HPLC fingerprints of single decoction of Radix scrophulariae by taking harpagoside peak as the reference peak,35 common peaks were marked in the HPLC fingerprints of single decoction mixture and combined decoctions by taking chlorogenic acid peak as the reference peak;24 peaks belong to Lonicerae similis Flos and 11 peaks belong to Radix srophulariae;Peak 5,10,15,16,17,22,24,25,26,33 and 34 respectively correspond to harpagide,neochlorogenic acid,chlorogenic acid,cryptochlorogenic acid,caffeic acid,isochlorogenic acid B,angelo glucoside C,isochlorogenic acid A,isochlorogenic acid C,harpagoside,cinnamic acid,respectively;In combined decoction,the total peak area was decreased,10 peaks’ area decreased markedly,1 peak disappeared,and 10 peaks’ area increased significantly;In single decoction mixture,2 peaks’ area decreased and12 peaks’ area increased significantly.The content of the index components changed more obviously in combined decoction,but of which changed little in single decoction mixture.Hence the type of chemical components had little difference between Single decoction,Single decoction mixture and combined decoctions of Lonicerae similis Flos and Radix scrophulariae crude drugs,but the size of the peak areas was obviously different,the different method of mixing liquid had different effect on the content of active ingredients.

Key words: drug pair, Lonicerae similis Flos, Radix scrophulariae, HPLC, fingerprint, index component