Tablet testing calculation

Tablets were prepared from both the microcapsules and mixtures using a Dartec Ltd universal testing machine. The quantity of drug contained was a nominal 200 mg and the punch diameter was 10 mm. Compression was at a constant rate of 1 kN s 1 with tablets prepared at 2, 5 and 10 kN. The tensile strength of the tablets was calculated using the formula T=2P/Dtn. The characteristics of the tablets prepared are shown in Table 1.

The stresses developed in convex tablets tested undergoing the diametral compression test have been examined by Pitt et al. (1989), who proposed the following equation for the calculation of the tensile strength ... 

Example 61 The raw data, given as %-of-nominal values with one decimal place, are found in Table 4.37 For each group of 10 values the mean and the standard deviation were calculated. Using these, the t-values for the differences L - mean, with L = 75, 85, 115, resp. 125% were determined they are all above 2.9, indicating low risk. The corresponding CP-values were calculated the differences ACP75-85 and ACP 15-125 were added and multiplied by 100 to obtain the approximate risk, in %, of finding a result between the inner and the outer limits. For a content uniformity test with n = 10 tablets, a risk of 0.003872% translates into a deviant result once every 20-25 trials, or, with six CU runs per batch, every third or fourth batch. 

Figure 4.51. Distribution of experimental data. Six experimental formulations (strengths 1, 2, resp. 3 for formulations A, respectively B) were tested for cumulative release at five sampling times (10, 20, 30, 45, respectively 60 min.). Twelve tablets of each formulation were tested, for a total of 347 measurements (13 data points were lost to equipment malfunction and handling errors). The group means were normalized to 100% and the distribution of all points was calculated (bin width 0.5%, her depicted as a trace). The central portion is well represented by a combination of two Gaussian distributions centered on = 100, one that represents the majority of points, see Fig. 4.52, and another that is essentially due to the 10-minute data for formulation B. The data point marked with an arrow and the asymmetry must be ignored if a reasonable model is to be fit. There is room for some variation of the coefficients, as is demonstrated by the two representative curves (gray coefficients in parentheses, h = peak height, s = SD), that all yield very similar GOF-figures. (See Table 3.4.)...

Most pharmacopoeias include a simple weight test on a specified number of tablets that are weighed individually. The arithmetic mean weight and relative standard deviation (i.e., mean divided by standard deviation) of these tablets is then calculated. Only a specified number of test tablets may lie outside the prescribed limits. These specifications vary depending upon the type of tablet and amount of active present. 

Content uniformity is a USP test is designed to establish the homogeneity of a batch. Ten tablets are assayed individually after which the arithmetic mean and relative standard deviation (RSD) are calculated. USP criteria are met if the content uniformity lies within 85-115% of the label claim and the RSD is not greater than 6%. Provision is included in the compendium for additional testing if one or more units fail to meet the standards. 

From a test of the tablet s flexure, tensile strength (oy) is calculated from the following equation ... 

Example 5 Multiple-Factor Stability Study A well-known example introduced by Shao and Chow [19] is used to illustrate the application of shelf life calculations for a multifactor case. A stability study was conducted on a 300-mg tablet of a drug product to establish the shelf life for each of the two types of packages used for this product bottle and blister. The results are shown in Table 24. Each type of package includes five batches. The tablets were tested for potency at 0, 3, 6, 9,12, and 18 months. Determine the shelf life based on these stability data. 

Compaction properties of each material were determined with a standardized test performed on a custom-built hydraulic compaction simulator using 8 mm (0.3150 in.) round flat-faced punches. A linear saw-tooth upper punch position profile was selected with a punch velocity of 300 mm/sec for both punch extension and retraction. The lower punch position was at a fixed position within the die during the compaction event. The powder weight loaded into the die for each compression was calculated from the equation below so as to form a cylindrical tablet having a thickness-to-diameter ratio of 0.30 at a theoretical SF of 1.0. These dimensions are typical of commercially elegant tablets. 

Calculate the content of Ci7Hi8FN303 in the tested tablets using the declared content of Ci7Hi9C1FN303 in ciprofloxacin hydrochloride... 

Alpdogan and Sungur [50] developed an indirect atomic absorption spectroscopy method for the determination of mefenamic and flufenamic acids, and diclofenac sodium, based on the complexation with copper (II) amine sulfate. The complex was extracted into chloroform, and the concentrations of substances were determined indirectly by AAS measurement of copper after re-extraction into 0.3 N nitric acid solution. The developed method was applied to the assay of the substances in commercial tablet formulations. The results were statistically compared with those obtained by HPLC method by t- and F tests at 95% confidence level. Calculated t and F values were both lower than the table values. 

The first experimental design we are going to consider involves the measurement of the same end-point in two groups of people, rats, tablets (or whatever). We calculate the mean value of the end-point in each group and then want to test whether there is convincing evidence of a difference between the two mean values. The procedure we use is a two-sample f-test, the term two-sample reflecting the fact that we are comparing two distinct samples of individuals. 

Then a known concentration of each analyte is prepared. The absorbance of these solutions are measured at each of the two wavelengths. Solving the two simultaneous equations, two equations for c and C2 are obtained. Then the known values of individual concentrations and calculated values of the four molar extinction coefficients are substituted in the derived equations to arrive at the unknown concentrations of the two components in the mixture. Multicomponent analysis is normally used in the dissolution testing of tablets. Standard hardware and software components for multicomponent dissolution testing based on compendial method are available from instrument manufacturers. 

This technique is satisfactory when comparing tablets of the same size and shape, such as in-process control. However, if virtually identical tablets are not being tested, problems may arise. The force is sometimes expressed as the compression pressure, obtained by dividing the force by the cross-sectional area of the punch. This is valid if the punch has a flat surface, the area of which can be easily calculated but in practice this is often not the case, and conversion between compression force and compression pressure involves assumptions regarding the area of the punch face, which may not be valid. 

In this study, dissolution profiles of carbamazepine tablets exposed to high humidity were classified by the Maha-lanobis distance calculation and the bootstrap method using full spectra and PCA. This use of full spectra required access to an IBM-3090 600J supercomputer. In multiple tests, the bootstrap calculation proved more accurate than the Mahala-nobis calculation. In one experiment, nine tablets with slow dissolution rates were used as a training set. Twenty-one tablets with a variety of dissolution rates were used to test the model. The modified bootstrap calculation correctly identified all tablets with faster dissolution rates than the training set, while the Mahalanobis calculation incorrectly identified 58% of the tablets with a higher dissolution rate. 

Mixing or blending is a critical process in the manufacture of dosage forms, especially in the production of tablets and capsules.The tablets or capsules prepared from the blend of poor mixing with active ingredients and excipients may fail the quality control test for content uniformity of the dosage forms. The acceptance limit according to the USP is based on the calculation of an individual assay of 10 tablets with a relative standard deviation equal to or less than 6%. Failure to meet the criteria results in rejection of the production lot. 

The proper selection of sampling techniques or sampling devices affects the calculation value of the relative standard deviation of a powder mixture, the indication of homogeneity. With the use of conventional side slit thief for sampling for blend uniformity analysis, discrepancy between the two values (blend uniformity versus content uniformity) can be determined. In the manufacture of some tablets, the relative standard deviation of the blend uniformity of a lot of bulk powder mix was found to be unacceptable and should have been rejected, whereas the tablets prepared with that powder blend unexpectedly met the content uniformity test. The noncorrelated relative standard deviation values of these two tests required clarification. 

The application of NIR in the pharmaceutical industry can be qualitative or quantitative. Analytical samples can be liquid, solid, or vapor. Identification of a sample by fingerprint to compare with the reference standard is an example of a qualitative application. Materials such as active drug substances, organic liquids and solvents, excipients, and packaging materials can be tested rapidly for identity in the receiving area. Other applications encompass the identification of the film layer of coated tablets and the study of blending of active drug substances with excipients calculated by a chemometric technique with the use of computer software. ... 

The disulfonamide is a known organic impurity usually found in acceptable quantities in the final dosage form. A specific impurity test is conducted to determine the amount of disulfonamide present, ensuring that the quantity is acceptable. For the tablet form, the sample preparation and the chromatographic system is the same as that for the assay tests, allowing them to be run concurrently. An external standard solution of known concentration of disulfonamide is prepared and the peak responses recorded are used to calculate the amount of disulfonamide present in the sample. 

Fliestand and Smith (1984) proposed three indices referred to as Tabletting Indices. The three indices are a strain index, bonding index and the BFI, which was described in the section on Capping. The strain index is a measure of the strain present in a material following compaction and is a measure of elastic recovery calculated by a dynamic indentation hardness test. The bonding index is a measure of the material s ability to deform plastically and form bonds and is the ratio of a compact s tensile strength and indentation hardness. 

---