A Model System for the Production of Aqueous Tablet Film Coatings for Laboratory Evaluation

Inter-tablet coating variability: Tablet residence time variability

“…These statistics are of interest since coating material accumulates predominately on a tablet's surface when tablets pass through the spray zone on the bed free surface. The studies have consistently shown that the average surface residence time of a tablet decreases as the drum rotation speed and fill level increase (Prater et al, 1980;Leaver et al, 1985;Yamane et al, 1995;Tobiska and Kleinebudde, 2001;Sandadi et al, 2004;Pandey and Turton, 2005). The standard deviation of the exposure time per pass has been shown to follow similar trends (Leaver et al, 1985;Yamane et al, 1995).…”

“…The statistics of tablet residence time on the free surface of a bed within a rotating drum and corresponding tablet circulation times have been widely investigated using a variety of techniques (Prater et al, 1980;Leaver et al, 1985;Yamane et al, 1995;Tobiska and Kleinebudde, 2001;Denis et al, 2003;Sandadi et al, 2004;Pandey and Turton, 2005;Kalbag et al, 2008). These statistics are of interest since coating material accumulates predominately on a tablet's surface when tablets pass through the spray zone on the bed free surface.…”

Inter-tablet coating variability: Residence times in a horizontal pan coater

“…Previous investigations (Prater et al, 1980;Leaver et al, 1985, andSandadi et al, 2004) indicate that the time a tablet spends in the spray zone as well as the frequency with which it returns to the spray zone are critical parameters for determining inter-tablet variability. These previous studies have presented measurements of similar, but different, quantities such as "residence time per pass'' and "circulation time''.…”

“…The statistics of tablet residence time per pass on the free surface of a bed within a rotating drum and corresponding tablet circulation times have been widely investigated using a variety of techniques (Prater et al, 1980;Leaver et al, 1985;Yamane et al, 1995;Sandadi et al, 2004;Pandey and Turton, 2005;Pandey et al, 2006). These statistics are of interest since coating material predominately accumulates on a tablet's surface when tablets pass through the spray zone on the bed's free surface.…”

In situ, near real-time acquisition of particle motion in rotating pan coating equipment using imaging techniques

“…Although signal intensity was recorded, no projected surface area data was presented. Prater et al (1980) studied the tablet appearance times using photographic and manual counting methods using a bed containing different colored tracer tablets. Parker et al (1993Parker et al ( , 1997) used a positron emission particle tracking technique (PEPT) to track a radioactively labeled tracer particle in a partially filled horizontal rotating drum.…”