Preparation And Characterization Of Berberine Hydrochloride And Trimethoprim Sustained-Releasenanospheres

In this paper,the study is to prepare a sustained-release nanospheres of Berberine Hydrochloride and TMP based on two kinds of biological materials,Chitosan and SBE7-?-CD.In the first place,it's necessary to prepare the inclution complex of TMP and SBE7-?-CD.Then TMP-SBE7-?-CD inclution complex is used to prepare the NP by ionic gelation method,in the meantime,adding berberine hydrochloride in the preparation process.Finally,a new sustained-release nanospheres which loaded TMP and berberine hydrochloride is obtained by centrifuge separation and freeze drying.To examine their pharmaceutical properties and bioactivity,there are many tests to be adopted,like dissolution experiment,stability experiment,transdermal experiment and bacteriostasis activities in vitro.(1)In the section of TMP-SBE7-?-CD inclusion complex,the phase solubility experiment proved that the inclusion ratio of TMP and SBE7-?-CD is 1:1.The TMP/SBE7-?-CD inclusion complex was prepared by the ultrasound-freeze-dry method,and the preparation conditions was optimized by Box-Behnken Design-response surface method(BBD-RSM).Inclusion complex was characterized by FT-IR,DSC,XRPD and 1H NMR.Molecular docking method was used to simulate 3-dimensional conformations of the inclusion complex and calculate the binding energy.The results show that the optimum conditions of the preparation of TMP/SBE7-?-CD inclusion complex were: inclusion temperature(52oC),time(45min),ratio of SBE7-?-CD/TMP(1.7:1)and ultrasonic power 150 W.All characterization methods(FT-IR,DSC,XRPD and 1H NMR)identifies the structure of TMP/SBE7-?-CD inclusion complex.The best docking conformation was consistent with the analysis results of characterizations with the low binding energy(-9.015kcal/mol).(2)In the section of nanospheres preparation,the results of factor experiments show that concentration and ratio of chitosan and SBE7-?-CD both have obvious influence onnanospheres.Particle size and particle dispersion index(PDI)of microphere increase with the increase of concentration;Particle size of nanospheres also increase with the increase of the ratio,but PDI contrary to it.Zeta Potential of nanospheres is increasing with the increase of concentration and the ratio respectively.These are due to the changes of ionic gelation reaction caused by concentration and the ratio.Taking everything into account,the concentration for next experiments is 3mg·mL-1,the ratio is 1:1.The characterization methods(FT-IR and DSC)proved the formation of NP.Under the condition of the above,particle size of the NP is 522.6nm,Zeta Potential of the NP is +39.5mV.(3)In the section of preparation of the sustained-release nanospheres,the TMP-SBE7-?-CD inclusion complex is used to prepare the nanospheres by ionic gelation method,in the meantime,adding berberine hydrochloride in the preparation process.At the end,a sustained-release nanospheres of Berberine Hydrochloride and TMP is obtained.The characterization methods(FT-IR and DSC)proved the formation of the sustained-release nanospheres.Particle size of the sustained-release nanospheres is 606.0 nm larger than blank nanospheres,because of the insertion of berberine hydrochloride.(4)The results of stability experiment show that the sustained-release nanospheres of Berberine Hydrochloride and TMP has good stability,but it needs dry preservation.In the dissolution experiment,the acumulative dissolution rate of Berberine Hydrochloride and TMP is 51.9% and 43.5% at 120 min,significantly lower than the physical mixture of compound.And in reansdermal experiment,the accumulative penetration of Berberine Hydrochloride in the sustained-release nanospheres is 126.89 ?g·cm-2 at 24 h,and that of TMP in the sustained-release nanospheres is 31.75 ?g·cm-2.Both are slower than the physical mixture.The results of bacteriostasis test in vitro also show that antibacterial effect of the sustained-release nanospheresoccurred later than physical mixture.Allexperiments proved the good sustained-release ability and bioactivity of the sustained-release nanospheres.