In pharmacy, an analytical procedure is typically developed to test certain defined characteristics of a drug. Set against some accepted criteria for the identified characteristics, this process should follow a scientific approach based on a researcher’s intended purpose, as well as overall scope of the analytical method.
Some factors that should be considered during development of an analytical method include specificity, limits of detection, linearity, range, accuracy, precision and limits of quantification or LOQ. Other integral parts of the method are validation and inclusion of the hospital pharmacy in every stage possible.
The Analytical Method Development involves a step-by-step method that takes into consideration equilibration times, scan/injection sequence with blanks, samples, placebos, sensitivity solution, controls and standards needed to maintain objectivity of the system.
Confirmatory test procedures will be put in place to ensure the unit functions correctly as a single integrated system. Other system suitability criteria such as peak tailing may also be required when applicable. During the early stages of method development, robustness of methods should be evaluated since this characteristic can help you determine which particular method would be submitted for approval by relevant pharmaceutical bodies.
Analytical procedures in preliminary stages of development are actually based on mechanistic understanding of the basic methodology, including prior experience. Note that experimental data from preliminary procedures can be applied as guide for further development, preferably submit development data as per the method validation criteria to experts within the pharmacy testing board to see if they support the findings.
Though method parameters can sometimes be altered, you can only understand effects of such changes by adopting a systematic approach for method robustness study. Start with an initial risk valuation then follow up with multivariate experiments. These approaches allow you to comprehend factorial parameter effects on method performance, and may also include analyses obtained from different stages of the drug manufacturing process from formulation to finished product. Some of the parameters to consider in Analytical Method Development include:
A. Principle/Scope. Involves describing the basic principles of an analytical test/technology, including target analytes and sample types.
B. Apparatus/Equipment. List all the necessary approved equipment and components, some of which are instrument type, detector, dimensions and filter type.
C. Operating Parameters. It involves qualified optimal ranges and settings, including permitted adjustments that are supported by sources or validation findings crucial to the analysis. For even more vivid depictions of the project, a sketch drawing with experimental configuration or integration parameters may be put to use as applicable.
The final stage in Analytical Method Development is data reporting, which is presenting the numeric findings consistently using instrumental capabilities and an accepted criteria. This method should show what format to consider when reporting results, such as by weight/volume or percentage label claim. All representing the specific number of probable figures required. According to American Society for Testing and Materials (ASTM), there’s a standard method used for testing data to determine their conformance with set specifications.
For the chromatography technique, you should mention retention times (RTs) for identification using reference standard comparison basis, as well as relative retention times (RRTs) consisting of known and unknown impurities or acceptable ranges and sample findings on reporting criteria.