Joseph B. Schwartz

Some Effects of Relatively Low Levels of Eight Tablet Disintegrants on a Direct Compression System

AbstractEight common tablet disintegrants (Amberlite IRP-88, Corn Starch U.S.P. CLD, Explotab, Ac-Di-Sol, Sta-RX 1500 Starch, Polyplasdone XL, and Guar Gum) were used in concentrations of 0, 0.25, 0.5, 1 and 2% (w/w) in a direct compression system of 75:25 Unmilled Calcium Phosphate Dihydrate/Anhydrous Lactose. Using a Recording Powder Flowmeter (RPF) it was noticed that linearity of flow was relatively unaffected while g/sec. flow rate decreased with increasing concentrations. Each system was then lubricated and tableted keeping the applied pressure relatively constant. Evaluation of the resulting tablets showed that even at very low disintegrant concentrations, significant reduction in disintegration time took place. At the same time, very few detrimental effects often seen with tablet disintegrants, were noticed.

The Binding and Disintegrant Properties of the Corn Starch Fractions: Amylose and Amylopectin

AbstractCorn Starch USP consists of the two glucose polymers, amylose and amylopectin, whose normal ratio is 27%:73%. This study was initiated to determine whether a variation in this ratio would have any benefit in pharmaceutical granulations. Starch pastes prepared by varying the amylose/amylopectin ratio were used to granulate a dicalcium phosphate system and the resulting tablet properties were evaluated.Physical mixtures of the polymers and also special hybrid polymer mixtures were studied. Binding and disintegrant properties of the starch fractions do vary with the amylose/ amyloptectin ratio and with the degree of starch hydrolysis during the heating (cooking) phase of starch paste preparation. The results of this study give some indication as to the binding and disintegrant activity of starch and its fractions.

Selecting Key Pharmaceutical Formulation Factors by Regression Analysis

AbstractThe use of Selective Regression Analysis to determine which formulation factors are governing product properties is demonstrated. The techniques of using and combining the two procedures called “All Possible Regression” (APR) and “Stepwise Regression” (SWR) are presented and applied to a multivariate pharmaceutical formulation problem.The technique was successfully applied to a system consisting of 10 response variables (tablet properties). Analysis of the results showed that for this formulation compression pressure and lubricant level exert the greatest effect on the majority of the properties. The results obtained from this method of analysis can aid the formulator in selectively controlling the product properties of choice while leaving the others undisturbed. Selective Regression Analysis also provides a basis for understanding the underlying mechanism of the system under consideration.