RESUMO
<p><b>OBJECTIVE</b>To study the effect of quaternary ammonium salt of chitosan (HACC) in purifying aqueous extracts of Zhisou Dingchuan oral solution.</p><p><b>METHOD</b>Modified quaternary ammonium salt of chitosan was used to flocculate aqueous extracts of Zhisou dingchuan oral solution, with turbidity degree and the retention rate of ephedrine and glycyrrhizin as indicators, to detect the influences of flocculant dosage, suspension temperature, mixing speed and time on flocculation effect. The optimum process conditions were found through orthogonal experimental design.</p><p><b>RESULT</b>The optimum process conditions: the flocculation temperature 30 degrees C, HACC's dosage 0.4 g x L(-1), the fast mixing speed 500 r x min(-1) and its time 1 min, the slow mixing speed 50 r x min(-1) and it time 2.4 10 min. Under the conditions, the retention rate of ephedrine was 97.6%, the turbidity degree was 1.1 NTU and 2.8 NTU after 30 days.</p><p><b>CONCLUSION</b>HACC can be used to purify aqueous extracts of Zhisou Dingchuan oral solution.</p>