Factor f1 indicates the percentage difference (dissimilarity) between two dissolution profiles; f2 is the logarithm of the reciprocal square root transformation of the sum squared error. It indicates the average percentage of similarity between two dissolution profiles.
What is f2 in dissolution?
The factor f2 measures the closeness between the two profiles. An average difference of 10% at all measured time points results in a f2 value of 50. FDA has set a public standard of f2 value between 50-100 to indicate similarity between two dissolution profiles.
What are dissolution parameters?
2. INTRODUCTI ON 3 DEFINATION : • • Dissolution rate may be defined as amount of drug substance that goes in the solution per unit time under standard conditions of liquid/solid interface, temperature and solvent composition.
What is f1 in dissolution?
The factor, f1, is the average % difference over all time points in the amount of test brand dissolved as compared to the reference brand. The f1 value is 0 when the test and the reference profiles are identical and increases proportionally with the dissimilarity between the two profiles.
What is similarity factor f2?
The factor f2, known as the similarity factor, measures the closeness between the two profiles:(1) f 2 = 50 · log 1 + 1 n ∑ t = 1 n ( R t – T t ) 2 – 0.5 × 100 where n is the number of time points, Rt and Tt are the dissolution value of the reference and test product at time t, respectively.
What is RSD in dissolution?
Dissolution results may be considered highly variable if the relative standard deviation (RSD) is greater than 20% at time points of 10 minutes or less and greater than 10% RSD at later time points. 1 However, most dissolution results exhibit less variability than this.
How do you calculate dissolution factor?
Formula for determination of percentage of release of drug from in vitro dissolution testing
- Concentration of drug (µg/ml)= (slope × absorbance) ± intercept.
- Amount of drug = Concentration × Dissolution bath volume × dilution factor.
What is f1 value in dissolution?
0
The factor, f1, is the average % difference over all time points in the amount of test brand dissolved as compared to the reference brand. The f1 value is 0 when the test and the reference profiles are identical and increases proportionally with the dissimilarity between the two profiles.
What are F1 and F2 dissolution profiles?
Liza, f1 and f2 are ,in fact , mathematical approaches used to compare dissolution profiles of reference and test products.
What is the difference factor and similarity factor in dissolution profiles?
Because of the nature of measurement, f1 was described as difference factor, and f2 as similarity factor (2). In dissolution profile comparisons, especially to assure similarity in product performance, regulatory interest is in knowing how similar the two curves are,…
What is regulatory interest in dissolution profile comparisons?
In dissolution profile comparisons, especially to assure similarity in product performance, regulatory interest is in knowing how similar the two curves are, and to have a measure which is more sensitive to large differences at any particular time point.
How to compare the dissolution profiles of different lots?
Model-independent mathematical approach proposed by Moore and Flanner to calculate f1 and f2 to check the similarity between dissolution profiles of different lots. This is the highly appropriate for dissolution profile assessment for comparison when there is t-h-r-e-e or m-o-r-e dissolution time points’ comparison need to be done.
