Research On Fibirin Glue Based Isoniazid Sustained-release System

Objective: To characterize a sustained-release drug gel system made ofdifferent concentrations of isoniazid with fibrin gel as the carrier undersimulated body temperature in vitro.Methods: Mixing two kinds of thrombin, four different concentrations ofisoniazid to form eight combinations of thrombin mixtures. Adding the sameconcentration of aprotinin and fibrin to each mixture to form eightcombinations of gel with thrombin concentration of7.5IU/ml and10IU/ml, andwith isoniazid concentration of1mg/ml,5mg/ml,10mg/ml and20mg/ml. Themixtures are labelled as A1, A2, A3, A4, B1, B2, B3, B4respectively. Theformation of the gel is laid in37℃water bath. The releasing of fibrin gluewas recorded for every24hours and the released fluid was removed until thegel dissolved completely. High performance liquid chromatography is used todetect the concentration of the released isoniazid and the data is analyzedusing SPSS19.0software.Results: Higher thrombin concentration shortens the gel forming time. Withthe increase of the isoniazid concentration, the gel forming time becomeslonger(P <0.05). The two different thrombin concentrations have no effect ongel sustained release time (P=0.604). Other than the A4, B4groups, all groupsshowed a slower releasing rate, and the sustained release time becomes shorterwith the increased isoniazid concentrations (P <0.05). The time course of the average daily released amount of isoniazid shows the similar pattern betweenthe two kinds of thrombin gel, where the released amount for A1, B1, A2, B2groups gradually decreases. The correlation coefficient of time course of theaverage daily released amount of isoniazid for group A were greater than thatfor group B, where the linear correlation coefficients for group A1and A2arethe highest, withγ of-0.976for both groups. The regression equations wereY=4.093-0.288X, Y=16.138-1.156X (P <0.05). The curves of the cumulativerelease of isoniazid with time are different for different isoniazidconcentrations, where A1andB1groups releases low doses slowly, A3and B3groups releases large doses quickly, and A2and B2groups show a pattern inbetween.Conclusion: Fibrin gels can be used as a slow release carrier ofisoniazid; concentration of isoniazid has a significant effect on thecharacteristics of the release profile.