Development Of Guilong Rheumatism Cataplasm

Backgruound:Guilong Rheumatism Plaster was a original formula from Rheumatism Department of Guangdong Second TCM hospital,which has been used for treating rheumatoid arthritis in clinic for years.It can relieve joint pain and related syndromes.The prescription was comprised of Rumulus Ginnamomi,and 9 other herbal ingredients,which have the therapeutic effects like dispelling Rheumatism,warming veins and arteries,activating blood circulation and relieving pains.However,many problems exist in preparing,quality control and clinical use of Guilong Rheumatism Plaster.The extraction process of herbal medicines is rough,the drug loading capacity is small,and the quality control of intermediate extract and final preparation was poor.When peeling off,the plaster is not easy for complete removal with much residue on the skin,and it sticks hair off as well.It also develops strong skin irritation.Taking all these into account,Guilong Rheumatism Cataplasm was developed and the quality control of intermediate extract and final product was studied to expect higher quality as well as better compliance and efficacy.Objectives:To study the preparation process of Guilong Rheumatism Cataplasm,to estabilsh the quality specification of the intermediate extract and the product of Guilong Rheumatism Cataplasm,and to investigate the safty of Guilong Rheumatism Cataplasm preliminarily.Methods:1.The volatile and non-volatile ingredients contained in the herbal medicine were extracted,concentrated and dried separately to prepare intermediate extract of Guilong Rheumatism Cataplasm.The extraction process condition was optimized.2.A HPLC method was developed for measuring the content of benzoylmesaconine in Guilong Rheumatism Cataplasm,and the method was validated.3.The quality control of the intermediate extract was evaluated by using qualitative identification and content determination.4.The adhesives,humectants and cross linking agents were screened by using single-factor test and orthogonal design.The optimal formulation was validated by experiments.5.Referring to Chinese Pharmacoepia(Edition 2015),the quality control of Guilong Rheumatism Cataplasm was studied on 3 batches of final products.6.The skin irritation of Guilong Rheumatism Cataplasm and Plaster was investigated in guinea pigs after single dosing,multiple dosing and repeated peeling.Results:1.The optimal extraction process condition was screened as follows.Cassia Twig,Asarum,Cinnamomum cassia and Notopterygium was soaked in 8-time volume of water for 1 h followed by 6-hour refluxing,and the volatile oil extract was collected.The residue was mixed with the other herbal medicines for further decocting after 1-hour soaking in 8-time volume of water.The decocting was repeated for three times.The extract liquid was mixed together and concentrated to a density of 1.20 to 1.30 at 60?under reduced pressure.The concentrated extract was vacuum dried to yield a powder at70?.The volatile oil extract was added in the powder to obtain intermediate extract.2.HPLC method was developed to determine the content of benzoylmesaconine in Guilong Rheumatism Cataplasm,and there was a good linear relationship in the range of16.4-98.4?g.m L-1.The method had good specificity,precision,stability,accuracy and repeatability.3.The quality of intermediate extract is controlled by the following items.The qualitative identification of intermediate extract was tested by thin layer chromatography(TLC)of prepared Radix Aconiti,prepared Radix Aconiti Kusnezoffii,Herba Asari Mandshurici,and Ficus hirta Vahl var.palmatiloba(Merr.).The yield of extract is not lower than 11.0%and the loss on drying is not higher than 5.0%.No burnt debris and insoluble substance is contained in the intermediate extract when dissolved.The content of benzoylmesaconine is measured by HPLC method and should not be less than 0.45mg/g in intermediate extract.4.The optimal formulation is as follows.Carbomer 940-NP700 gel(1:4)is used as adhesive,1,2-propylene glycol is used as humectant,and dihydroxyaluminium aminoacetate is used as cross linking agent.The amount of adhesive,humectant and cross linking agent is 10 g,6 g,0.1 g,respectively.33% gelatin solution was used as thickening agent.By using the optimal formulation,Guilong Rheumatism Cataplasm of good ductility,suitable stickness,smooth appearance and even color was prepared.5.Based on the study of quality of three batches of Guilong Rheumatism Cataplasm,the quality specification draft was provisionally set and included the following items.Heat resistance,formability,content uniformity,drug release,microbial limit should meet the requirements of Pharmacopoeia of the People's Republic of China(Version I,Edition2015).The label content of paste was 9.0 g per piece,and weight variation was limited within ±5%.Calculated by the content of benzoylmesaconine,the label content was not less than 0.65 mg per piece.The cataplasm should retain 15# steel ball in initial adhesion force test,and the retaining time should more than 190 s in adhesion force test.6.In skin irritation test in guinea pigs,Guilong Rheumatism Cataplasm showed weaker irritation to skin than Guilong Rheumatism Plaster,and was not susceptible to stick hair off.Conclusion:Guilong Rheumatism Cataplasm of good quality was developed through optimization of extraction process and matrix formulation as well as quality control study of intermediate extract and final preparation.The preparing process is reasonable,stable,feasible and controllable.This work provides scientific evidence for future scale-up production and clinical trial of Guilong Rheumatism Cataplasm.