Evaluation tools quality control tests

For the dissolution test to be used as an effective drug product characterization and quality control tool, the method must be developed with the various end uses in mind. In some cases, the method used in the early phase of product and formulation development could be different from the final test procedure utilized for control of the product quality. Methods used for formulation screening or BA and/or bioequivalency evaluations may simply be impractical for a quality control environment. It is essential that with the accumulation of experience, the early method be critically re-evaluated and potentially simplified, giving preference to compendial apparatus and media. Hence, the final dissolution method submitted for product registration may not necessarily closely imitate the in vivo environment but should still test the key performance indicators of the formulation. 

Tensile properties are used in the evaluation of batches of material as well as in determining the aging effects on polyurethane. Currently, the time taken for the preparation and stabilization of the samples does not make this test ideal for a batch-to-batch real-time quality control tool. Testing is normally carried out to one of the following standards ... 

Pigments and pigment dispersions have been and continue to be evaluated for color using a wide variety of methods. Over the years Oil Ink Tests, Latex Paint Tests, Liquid Ink Tests and PVC, Rubber, and Polyethylene Two-Roll Mill Tests have been used as Quality Control methods. We did not have extensive reproducibility data for these methods, but we felt that all of them could be improved using statistical tools. 

Color labs are outfitted with laboratory size equipment that simulates the larger machines used for production internally and by their customers. Typical processing equipment found in the lab are small extruders, two-roll mills, ban-burry mills, and media mills. Small rotational, injection and blow molding machines are used to duplicate the customers process. Instruments and computers are required for testing physical properties and color. Most labs have a computer-controlled color measuring system and a light booth to evaluate color. The spectrophotometer with computer is initially used to assist in colorant formulation and later as a quality control (QC) tool to provide certification of the quahty of match to standard. The light booth provides a standardized set of conditions to visually observe color and appearance. 

Cabinet corrosion tests have been used since the early 1900s as a means of evaluating the performance of coatings as a quality control tool for monitoring processes, and in some cases, as a method for accelerating corrosive activity. 

One critical remark is in order regarding papers published in the field of chemical sensors. Many such reports reflect a lack of input from qualified analytical chemists during the development and testing stages. Insufficient understanding is often apparent with respect to the analytical process itself and the difficulties involved in obtaining a truly reliable result indeed, many sensor researchers seem to be unaware of such basic problems as sample - matrix effects. Anyone who claims to have developed a new sensor should be required to demonstrate its effectiveness with a real sample under real conditions. The latter is required and called validation by international quality standards (ISO 25). Publications that fail to reveal this most important feature of a sensor are also essentially worthless. Chemical sensors are analytical devices. so they should be subjeet to the same standards of characterization as other instrumental tools, ( ality-control considerations mandate critical evaluation of any new molecular sensor presented to the scientific community. Every report concerning a new sensor development should clearly delineate the crucial features, with none omitted. 

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