For each timepoint, the mean percentage of dissolved iron was calculated from the six tablets, buy Seliciclib together

with the relative standard deviation. The mean values were plotted in dissolution curves for the two products under evaluation and allowed comparison by means of the similarity factor, f 2 (equation 1). $$f_2 = 50 \cdot \log \Biggm\lbrack100\over\sqrt1+ \mathop\sum\limits ^t = n_t = l [\bar R(t)-\bar T(t)]^2 \over n\Biggm\rbrack$$ (1) where n = number of points (two in this case); R(t) = mean percentage of iron dissolved at time, t, for Ferroliver® T(t) = mean percentage of iron dissolved at time, t, for Folifer®. The similarity factor is a logarithmic reciprocal square root transformation of the sum of squared errors and is a measurement of the similarity in the percentage of dissolution between the two curves. At least

three mean dissolution results from both curves obtained at the same timepoints were used for the calculations. An f 2 value of between 50 and 100 suggests that the two dissolution profiles Vadimezan mw are similar. Results The results of the dissolution profiles and degree of similarity for the two products are shown in table I and figures 1 and 2. Table I Mean amount of iron released from two iron- and folic acid-containing supplements, Folifer® and Ferroliver®: results from an in vitro dissolution study Fig. 1 Dissolution profiles showing the mean percentage of iron released over a 4-hour time period for Folifer® and Ferroliver®. Fig. 2 Dissolution profiles showing the mean absolute amount of iron released over a 4-hour time period for Folifer® and Ferroliver®.

During the first hour, 29.7 mg and 32.7 mg of iron was released from Folifer® and Ferroliver®, respectively. In percentage terms, the release rate was similar, as the iron content of the two supplements was similar. During the second hour, Folifer® showed a higher capacity for releasing iron than Ferroliver®, both in absolute terms and in relative terms. After 4 hours, the amounts of iron released by Folifer® and Ferroliver® were 59.4 mg and 48.5 mg, respectively. The mean comparative dissolution profiles of Folifer® and Ferroliver® were also assessed by determining the similarity factor, f 2, according to the formula shown in equation 1. The f 2 value between the two formulations was 41, showing a Niclosamide lack of similarity and in vitro bioequivalence. Discussion In vitro dissolution studies can Nutlin-3a solubility dmso provide important information on bioavailability and bioequivalence of various formulations. A dissolution test can be used as a tool to identify formulation factors that influence, and may have a crucial effect on, the bioavailability of a drug. Appropriate in vitro dissolution testing may be used in place of in vivo bioequivalence testing. Accordingly, dissolution testing should be investigated at different pH values (normally pH 1.2, 4.5, and 6.8).