Tablet evaluation HPLC

Bulk-tablet Etorphine HPLC Powder, add MeOH. sonicate, add mobile phase MCH-10, Micropak CH3CN-H 0(1 1), 1 ml/min 230 nm TLC also evaluated benzodiazepine HPLC [774] GC MS, urine [778] [485]... 

Application of DSC and HPLC to determine the effects of mixture composition and preparation during the evaluation of niclosamide-excipients compatibility showed that although some reactions occurred, niclosamide was compatible with a majority of common tablet excipients tested [63],... 

Raman often is evaluated as an alternative to an existing high performance liquid chromatography (HPLC) method because of its potential to be noninvasive, fast, simple to perform, and solvent-free. Raman was compared to HPLC for the determination of ticlopidine-hydrochloride (TCL) [43], risperidone [44] in film-coated tablets, and medroxyprogesterone acetate (MPA) in 150-mg/mL suspensions (DepoProvera, Pfizer) [45] it was found to have numerous advantages and performance suitable to replace HPLC. In an off-line laboratory study, the relative standard deviation of the measurement of the composition of powder mixtures of two sulfonamides, sulfathiazole and sulfanilamide, was reduced from 10-20% to less than 4% by employing a reusable, easily prepared rotating sample cell [46]. 

As an example, tablet samples for a product were prepared in an 85% organic medium and transferred into HPLC vials. An impurity peak was observed in some, but not all, of the tablet samples, blanks and standards. It was suspected that the solution in some of the vials may have come in contact with the HPLC Teflon caps and extracted a component from the cap. To evaluate this possibility, dissolving solvent was transferred into similar HPLC vials. These vials were capped with the Teflon caps and were kept inverted overnight to allow maximum contact of the solvent with the vial caps. A set of control samples were also prepared in which the vials were only filled halfway with dissolving solvent and care was taken not to allow the dissolving solvent to come into contact with the vial caps. These samples were analyzed by HPLC and, as shown in Fig. 10.3, confirmed the origin of the peak in question as being from the vial caps. In addition, the UV spectral analyses of the... 

Different types of syringe filters were then evaluated to try to remove the problematic excipients. Figure 10.4c shows that the use of an Amicon Ultra-4 centrifugal filter (Millipore, Billerica, MA) removed the residual HPMC from the sample solution but did not remove the starch. The Amicon Ultra-4 filter, however, does introduce later eluting filter-related peaks that fortunately do not interfere with any components of interest. Starch was not removed by any of the filters tested. As a result, excipient placebo samples were used as part of the method. These placebo samples were extracted and injected onto the HPLC system to confirm which peaks in the fixed combination tablet samples were excipient-related and these peaks were not quantitated or reported as drug-related degradants. 

Jedlicka A, Grafnetterova T, Miller V. 2003. HPLC method with UV detection for evaluation of digoxin tablet dissolution in acidic medium after solid-phase extraction. J. Pharm. Biomed. Anal. 33 109 115. 

The list below is a summary of test methods that are most likely to be required during the testing of most common dosage forms (tablets, capsules, and solutions). The list is by no means an exhaustive (since test methods to determine moisture content, pH, sterility, particulate matter, and microbial testing are not listed) and the selection of test methods depends on an evaluation of a dosage form and also on the phase of drug development. For each type of test, most common techniques utilized are listed in square brackets. As can be seen, HPLC can be employed for aU of the following test methods. 

A health food fad involves tablets of Spirulina sp. (blue-green algae). When the B12 concentration of algal health food (Spirulina tablets) has been determined by both L. delbrucekii ATCC 7830 microbiological and IF chemiluminescence methods, the values determined by the microbiological method are about sixfold to ninefold greater in the Spirulina tablets than the values determined by the IF chemiluminescence method. To evaluate whether the B12 found in the Spirulina tablets is true Bi2 or inactive Bi2-related compound, B12 compounds have been purified from the Spirulina tablets using silica gel 60 TLC and a reversed-phased HPLC, and then characterized. 

The study had three objectives first, changes in NIR spectra were correlated to the time aspirin tablets spent in the hydrator (the calibration had a correlation coefficient of 0.95 and SEE of 18.8 h) second, a calibration was developed for the prediction of tablet salicylic acid content (the researchers ensured that prediction of salicylic acid was based on changes in salicylic acid concentration, and not some related process, such as absorption of moisture, by evaluation of loadings spectra from principal component analysis of the data. The HPLC-determined salicylic acid levels ranged from 0.36 to 1.66 mg, and the NIR method allowed prediction of the degradant with a standard error of 144 mg) and third, the mass of water absorbed by the tablets was determined by NIR spectroscopy. 

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