Degree of Mixing in Disposable Polyethylene Bag

Abstract

In order to prevent cross-contamination caused by the mixing apparatus for dispensing powders, we proposed use of polyethylene bag which is disposable at each occasion of dispensing and is usable as a mixing apparatus. The degree of mixing of this bag was investigated using lactose powder and eosin-colored lactose powder, and efficiency of the bag was compared with that of an automatic dispensing mixer. As an index of the degree of mixing, coefficients of variation (C. V.) obtained from the concentrations of eosin were used. C. V. values not more than 6.08 was judged to be “good mixing.” As a result, good mixing in the disposable bag with total contents of 20 to 80 g was obtained by more than 40-time shaking. Mixing ratio of the 2 kinds of powder did not affect the degree of mixing. No differences were found between the disposable bag and automatic dispensing mixer. The above results indicated that the mixing procedure using the polyethylene bag is practically useful for powder dispensing.