Tabletting method

The results of this study confirmed the appropriateness of the paddle height (2.5 cm above the bottom of the vessel), paddle speed (100 rpm) and sampling zone (midway between the surface of the medium and the top of the rotating paddle, not less than 1 cm from the vessel wall) used in the tablet method. 

Table 132. General tabletting methods with particular regard to the point of addition of the disintegrant...

A summary page is generated upon completion of the tablet method validation. This gives the user a quick reference of where to find the data, and the conclusions of each experiment. It also alerts the analyst to any potential degradation. An example of a method validation summary for drug product can be found in Table 2. 

Heideman et. ah (51) developed a rapid HPLC method for the estimation of salicylic acid in aspirin tablets. Method involves the blending of tablets with acidic ethanol to extract the aspirin and salicylic acid rapidly. The resulting preparation is then immediately injected on to a 4.6 mm x 3 cm 5 micron reverse-phase column. Aspirin and free salicylic acid are determined simultaneously. The run time is less than 2 minutes. 

The other peaks demonstrate the power of NMR to identify and quantitate all the components of a sample. This is very important for die phannaceutical industry. Most of the peaks, including a small one accidentally underlying the methyl resonance of paracetamol, arise from stearic acid, which is connnonly added to paracetamol tablets to aid absorption. The integrals show diat it is present in a molar proportion of about 2%. The broader peak at 3.4 ppm is from water, present because no attempt was made to dry the sample. Such peaks may be identified either by adding fiirther amounts of the suspected substance, or by the more fiindamental methods to be outlined below. If the sample were less concentrated, then it would also be... 

Salem and Galan have developed a new method for determining the amount of morphine hydrochloride in tablets. Results, in milligrams, for several tablets containing different nominal dosages follow... 

Samples of urine are analyzed for riboflavin before and after taking a vitamin tablet containing riboflavin. Concentrations are determined using external standards or by the method of standard additions, fluorescence is monitored at 525 nm using an excitation wavelength of 280 nm. 

The technique of hydrodynamic modulation voltammetry (HMV), in which the rate of stirring is pulsed between high and low values, is demonstrated in this experiment. The application of HMV for the quantitative analysis of ascorbic acid in vitamin C tablets using the method of standard additions also is outlined. 

Direct Compression. This process is relatively simple and time saving. AH the ingredients are blended and then compressed into the final tablet. This is an excellent method, but encumbered by a number of problems. Not all substances can be compressed directly, necessitating a granulation step. Likewise, the flow properties of many blends of fine, particle-sized powders are not such as to ensure even filling of the die cavities of tablet presses. In addition, air entrapment can occur. 

The availabihty of spray-dried lactose, microcrystaUine cellulose, and other excipients allows for the use of granular rather than powdered phases. This eliminates some of the problems of particle segregation according to size (demixing) and even flow to the die. Direct compression eventually may be the preferred method of tablet preparation. 

The standard chemical and biological methods of analysis are those accepted by the JnitedStates Pharmacopeia XXIII as well as the ones accepted by the AO AC in 1995 (81—84). The USP method involves saponification of the sample (dry concentrate, premix, powder, capsule, tablet, or aqueous suspension) with aqueous alcohoHc KOH solvent extraction solvent removal chromatographic separation of vitamin D from extraneous ingredients and colormetric deterrnination with antimony trichloride and comparison with a solution of USP cholecalciferol reference standard. 

As described ia the USP, phytoaadioae is a mixture of the cis- and trans-isomers of vitamin IQ. This mixture should not contain mote than 103% and not less than 97.0% of total vitamin K content. The amount of the cis-isomer is also specified and is not to exceed 21%. In addition to the pure substance, the USP also describes methods for the analysis of parental as well as tableted forms of the vitamin (21). 

Properties of lakes that enhance their usefiilness iaclude their opacity, their abiUty to be iacorporated iato products ia the dry state, their relative iasolubihty, and their superior stabiUty toward heat and light. Such properties have made possible the more effective and more efficient preparation of candy and tablet coatings, and often eliminate the need to remove moisture from dry products before coloring them. Lakes have also made possible the coloring of certain products that, because of their nature, method of preparation, or method of storage, caimot be colored with ordinary color additives. 

Developed standai d validation procedure is demonstrated for validation of a spectrophotometric assay of ambroxol hydrochloride tablets. Without any considerable revisions, this approach may be applied to chromatographic methods. Recommendations for validation criteria were included in the State Phai macopoeia of Ukraine. 

A selective and sensitive spectrophotometric method for determination of atorvastatin and fluvastatin in tablets have been developed after derivatization with 9-chloromethylanthracene. Atorvastatin and fluvastatin were reacted with 9-chloromethylanthracene in hexane and then tetrabuthylammonium hydroxide for 20 at 90 °C. For spectrophotometric method the derivatives of atorvastatin and fluvastatin were measured at wavelengths, 301 and 303 nm, respectively. The developed method was applied to analyze the atorvastatin and fluvastatin contents in tablets. 

We proposed using MLC for assay of azithromycin in tablets and capsules. As alternative conventional reversed-phase HPLC method MLC was used for analysis of Biseptol (sulfamethoxazole and trimethoprim) tablets and injection. The MLC was proposed to assay of triprolydine hydrochloride and pseudoephedrine hydrochloride in tablets as alternative normal-phase HPLC method described in USP phamiacopoeia. 

Estimation of Other Alkaloids in Opium. Of the other alkaloids the most important is codeine, and processes for its estimation in opium have been described by Cespari, Andrews,and Annett and co-workers methods for its assay in admixture with other drugs in tablets and other products are also available. The estimation of papaverine has been described by Issekutz,i and of narcotine by Snesarov. As to methods for the separation and estimation of two or more of these subsidiary alkaloids, codeine and narcotine have been dealt with by van der Widen,narcotine and papaverine by Annett and Bose, ( and the bromination of codeine and narceine has been studied by Vaisberg et al. with a view to estimation by this means. 

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