Study On The Preparation Technology And Quality Standard Of Mo Xian Coating Agent

Molluscum contagiosum(MC)is a common disease in dermatology,with high pathogenicity and strong contagion,prevalent worldwide.In the treatment of this disease,physical therapy is mostly used in clinical practice.Although the operation is simple,it is easy to cause bleeding and pain and other problems.Patients with molluscum are mostly children and adolescents,and for patients with young age,intolerance of pain and more skin lesions limit the use of physical therapy.There are also problems such as difficulty in complete removing of it in one treatment,and patients need to be treated repeatedly.Han Cao Tincture is a traditional Chinese medicine prescription based on Eclipta prostrata,Portulaca oleracea,and borneol,which has a definite effect on the treatment of MC,and the effect is mild,and it is not easy to recur after healing and does not leave scars.After the application of the tincture,the solvent volatilizes,and the drug adheres directly to the surface of the skin,which is easy to cause drug loss due to friction.In addition,the dosage is not easy to control and some patients are not suitable for use,which limit its use and efficacy.Therefore,in this paper we tried to improve the original dosage form and developed the Mo Xian Coating Agent.When this agent is used,the drug film is applied to the lesion area,which can achieve precise treatment and enhance the efficacy.At the same time,the dosage form is convenient to use.The development of Mo Xian Coating Agent can not only make up for the shortcomings of clinical treatment methods,but also overcome the shortcomings of the original tincture,demonstrating important application prospects.In this paper,the preparation process,quality standard,and preliminary stability of Mo Xian Coating Agent have been studied systematically.In the study of the preparation technology,the film-forming materials,plasticizers,and transdermal enhancers were investigated,according to the film-forming performance indexes including the film-forming time,the film-forming ability,and viscosity of the solution.First,the film forming materials such as polyvinyl alcohol(PVA)0588,PVA 1788,PVA 2499,and polyvinyl pyrrolidone(PVPk30)were investigated,and PVA 0588 was selected with the amount of 4%-8%.Next,the plasticizers such as glycerol and propylene glycol were investigated,and glycerol was selected with the amount of 1%-2%.Finally,the transdermal enhancer such as Tween 80 was investigated,and the amount was controlled to 0-2%.An orthogonal experiment was designed and conducted with four factors at three levels,and the optimal preparation process was determined,namely,PVA 0588(6%),glycerol(2%),and Tween-80(0.5%).According to the optimal process,the Coating Agent was prepared and the process was further verified.The results indicated that the Coating Agent has good performance and the process is reasonable and feasible.Thin layer chromatography(TLC)was used for the identification of Eclipta prostrata,Portulaca Oleraeea,and Natural borneol in the quality control research.The results showed that the TLC of the three traditional Chinese herbs was clear without interference and thus has good specificity.Secondly,the film-forming time,pH value,relative density,and viscosity were tested.The film-forming time is 6-7 min,the pH value is between 6.0 and 6.4,the relative density is no less than 0.95,and the viscosity is between 60-70 mPa·s,which indicate that the Coating Agent has short film-forming time,is easy to apply,and has no irritation in use,with the pH value conforming to the pH range of normal human skin.The index components wedelolactone and oleracein B(OB)were determined by using liquid chromatography(HPLC).The measurement method for wedelolactone was as follows:Horizon C18(250×4.6 mm,5 μm)column;with methanol as mobile phase A and 0.1%of aqueous acetic acid as mobile phase B in a gradient elution(0～5 min,35%～52%A;5～25 min,52%A)at a flow rate of 1.0 mL/min;wavelength at 351 nm;and column temperature 30℃.The limit of the content of wedelolactone is established to be not less than 25.85 μg/mL.According to the literature method for measuring the content of Oleracein B,with 0.1%of formic acid as mobile phase A and acetonitrile as mobile phase B and in a gradient elution(0～30 min,89%～81%A;30～40 min,81%～80%A;40～55 min,80%A)at a flow rate of 0.8 mL/min;wavelength at 336 nm;and column temperature 30℃.Oleracein B was determined to be not less than 2.39 μg/mL using this method.Draft of the Quality Standard of Mo Xian Coating Agent was formulated according to the above identification,test and assay research.In the preliminary stability study,the key characteristics of the Coating Agent were investigated.Through the centrifugal,heat resistance,and cold resistance tests,the properties,delamination phenomenon,and film forming properties were investigated,and it was indicated that the preliminary stability of the Coating Agent was good.In conclusion,in this paper we have studied the preparation process and quality standard of the Mo Xian Coating Agent by using modern preparation technology and instrumental analysis,and have established a reasonable and feasible preparation process of the Mo Xian Coating Agent.The qualitative and quantitative methods are scientific and accurate,easy to operate,and the preparation is stable.This study provides a new approach for the treatment of Molluscum contagiosum.