Preparation and performance evaluation of soluble microneedles of total flavonoids from hibiscus leaves

XIE Shu-cai; CHEN Xiao-lan; WAN Jing; DENG Bi-li; DONG Na-na; HU Juan

doi:10.3969/j.issn.1003-3734.2024.02.011

Abstract：Objective:To prepare soluble microneedles of total flavonoids in Hibiscus leaves(TFH)and investigate their physicochemical properties and transdermal properties in vitro.Methods:The soluble microneedles were prepared by centrifugation,the substrate proportion,substrate to solvent proportion and drying conditions were investigated,the substrate amount was optimized by Box-Behnken response surface method,and the preparation process parameters of microneedles were finally determined.The drug loading was measured by HPLC,the physical appearance was observed by body optic microscope,and its puncture performance was evaluated by HE staining.The in vitro transdermal properties were investigated by combination with the Franz diffusion pool.Results:It was determined that the best prescription of total flavonoids soluble microneedle was gantrez s-97∶ polyvinyl alcohol(PVA)=1.5∶1,the ratio of matrix to solvent was 1∶4,and the needle body of DMNs-TFH was conical,the surface was flat,and the length was about 550 μ m.The area of each tablet was 2.79 cm2,the drug content(calculated by rutin)was(1.080 6±0.026)mg,and the drug content needle tip accounts for 10%.The results of in vitro skin penetration showed that the cumulative permeability of total flavonoids in DMNs-TFH could reach 70%after 24 hours,while the penetration of TFH solution was very little,which proved that soluble micro had good promoting effect on TFH transdermal delivery and could effectively penetrate the isolated skin.Conclusion:The prepared DMNs-TFH have good mechanical strength and large drug loading,which realizes the transdermal delivery of TFH.