Custom Premix Selecting "Custom Premix" option means that all of the beads you have chosen will be premixed in manufacturing before the kit is sent to you.
Dissolution testing is required by regulatory agencies before a drug can be released for clinical use or on the market. These tests are used in the development and evaluation of new formulations, for quality control of the drug product and to ensure that changes in the manufacturing process have no effect on the drug product quality and performance. Dissolution testing is also a useful tool to establish in vitro / in vivo correlations (IVIVC).
Many drugs are formulated as solid dosage forms for oral administration. Dissolution testing is used to predict the absorption of these drugs. It allows the study of the release of the active ingredient from the excipients of the dosage form (usually a tablet or a capsule) as well as its dissolution under physiological conditions. The dissolution medium is usually a buffer solution of either pH 1.2 (to represent gastric fluid), or 6.8 (to represent intestinal fluid), but other dissolution media may be used depending on the physicochemical characteristics of the drug and on the properties of its formulation. For example, surfactants or enzymes may be added to the buffers. The dissolution medium is placed in a vessel, and maintained at constant temperature (usually 37±0.5°C). Mild agitation conditions are maintained throughout the test. The most commonly used methods are the basket (Apparatus 1) and the paddle (Apparatus 2), but many other methods are available (flow-through, etc.). Samples are collected at specific times and analyzed.
Performing dissolution testing for more complex dosage forms such as extended-release formulations, transdermal patches, etc. presents a challenge, and specific dissolution testing procedures are being developed for them. Dissolution testing methods are established by local Pharmacopeias. The Pharmacopoeial Discussion Group (PDG) aims at harmonizing the methods described by the United States Pharmacopeia (USP), the European Pharmacopeia and the Japanese Pharmacopeia