GRANULATION MOISTURE-CONTENT ANALYSIS - AN EVALUATION OF 2 INSTRUMENTS

Reliable methods of determining moisture content of granulations are e ssential to develop products that are readily and consistently manufac tured. This study evaluated two instruments for loss on drying (LOD) m easurement, the Computrac model MA-5 and the Mark-I. Both instruments were evaluated using the USP oven method for LOD determination as a st andard. All of these instruments/methods involved thermogravimetric an alysis (TGA). Computrac MA-5 utilizes a heating coil as heat source an d Mark-I uses four parallel quartz infrared heaters as heat source. Re sults showed that the Mark-I moisture analyzer and the oven method gav e values much Closer to those predicted for the compounds tested, whil e the Computrac seems to be inconsistent in determining the LOD of mat erials which are in equilibrium with their bound water of hydration an d their evolved volatile compounds.