Issue link: https://www.e-digitaleditions.com/i/1000772
Tablets & Capsules July 2018 32C acceptance criteria is ±5 percent. In a similar manner, verify the volumetric flowrate of the exhaust air. Supply and exhaust air temperatures. The supply and exhaust air temperatures are important for effectively dry- ing the coated tablets. These temperatures must be care- fully controlled so that the fine mist of coating solution discharged by the spray guns evaporates quickly once it contacts the tablet bed, leaving a thin film on the tablets [2]. If the temperature is too low, overwetting of the tab- let bed can occur. You can verify the supply and exhaust air temperatures using a thermocouple thermometer. Select low, middle, and high temperature set points for the supply air within the system's operating limits. Measure the supply and exhaust air temperatures at these established set points and at the sampling points selected for the air flowrates using the calibrated thermocouple as a known test stan- dard. The input value will be the measured temperature display on the thermocouple, and the output value will be the actual temperature probe display. Obtain the reading error by subtracting the output value from the input value. The acceptance criteria for the supply and exhaust air temperatures is ±1°C. Pan rotation speed. The coating pan must rotate at a speed that will provide coverage of the pan without caus- ing the tablets to break [3]. The pan rotation speed should be increased gradually in conjunction with the coating solution spray rate, supply air temperature, and supply and exhaust air volumetric flowrates. The tablet coating pan rotation speed is expressed in terms of revolutions per minute (rpm) that can be verified using a calibrated tachometer as the known test standard. For the best results, four set points should be selected within the coater's operating limits. Using the tachome- ter, measure and record the pan's rotation speed and record the rpm displayed on the coater controller. The input value is the actual measurement obtained by the tachometer, and the output value is the value displayed on the coater. Calculate the reading error by subtracting the output value from the input value. The acceptance criteria for the pan rotation speed should be ±0.5 rpm of the value for each set point. Spray rate. The coating solution spray rate is directly proportional to the supply air temperature and supply and exhaust air volumetric flowrates. Pumping the coating solution into the tablet bed at an excessively high rate with an insufficient airflow temperature and volumetric flowrate will result in overwetting. If it is too low, the coating does not build up fast enough, resulting in tablet erosion. Note: The method described here for verifying the coating solution volumetric flowrate applies to systems using a peristaltic pump. The pumping flowrate can be expressed in terms of rpm that can be verified using a cal- ibrated tachometer as a test standard. For the best results, select four set points within in the operating limits. Using the tachometer, measure the pump speed and record the speed displayed on the pump. The input value is the value obtained using the tachometer, and the output value is the value displayed on the pump. The percent Dr. Schleuniger ® Pharmatron is a brand of Our new generation of tablet hardness and disintegration testers allow you to save time & money by maximizing the efficiency of your quality control process. Innovative technology paired with proven mechanics makes operation simple, reduces processing time, and provides precision results you can rely on. www.pharmatron.com Quality matters. How efficient is your quality control?