Abstract:Objective To investigate the effect of chylomicron flow on the distribution of baicalin nanoemulsion in the lymphatic tissue of rats and the lymph- targeting mechanism of baicalin nanoemulsion. Methods High- performance liquid chromatography was used to measure the concentration of baicalin in biological samples, and rats were given baicalin nanoemulsion or baicalin suspension by gavage at a dose 144.0 mg/kg. A rat model of chylomicron flow blocking was established to investigate the effect of chylomicron- mediated transmembrane transport on the distribution of baicalin nanoemulsion in lymphatic tissue. Results In the baicalin nanoemulsion group, the blocking of chylomicron flow affected the parameters such as area under the drug concentration- time curve and peak drug concentration in the spleen, thymus, and lymph nodes, while it had no influence on pharmacokinetic parameters in the baicalin suspension group. Conclusion Baicalin nanoemulsion stimulates the secretion of chylomicron, improves drug transport via the lymphatic pathway, and enriches the drug in lymphatic tissue, which may be the main mechanism for baicalin nanoemulsion to target lymphatic organs.