As an expert in pharmaceutical sciences, I can provide you with a comprehensive understanding of the term "Q" in the context of dissolution testing. Dissolution testing is a critical quality control method used in the pharmaceutical industry to evaluate the rate at which a drug product releases active ingredients into a particular medium that simulates the gastrointestinal tract. This test is essential for ensuring the efficacy and safety of oral solid dosage forms, such as tablets and capsules.
The term "Q" in dissolution testing typically refers to the quantity or quotient of the active pharmaceutical ingredient (API) that is released from the dosage form within a specified time frame. It is often expressed as a percentage of the labeled claim or the amount of API stated on the product's label. The USP (United States Pharmacopeia) sets forth guidelines and standards for dissolution testing, which are detailed in the individual monographs for each drug product.
The USP Dissolution testing involves three stages, and for each stage, acceptance criteria are defined in terms of the quantity Q. This means that the amount of API released at each stage must meet or exceed a certain percentage of the label claim to be considered acceptable. The percentage is established for each drug product in its monograph, which is a comprehensive description of the drug's identity, quality, purity, and performance characteristics.
The concept of quantity Q is closely related to the **Probability of acceptance of the dissolution test (Pa)**. This is a statistical measure that predicts the likelihood that a batch of drug product will pass the dissolution test based on the established criteria for Q. For example, if the criteria state that at least 75% of the labeled amount of API (Q) must be dissolved within a certain time, and the test results consistently show that 80% of the API is dissolved, the Pa would be high, indicating a high likelihood of passing the test.
It is important to note that the value of Q is not static; it can vary depending on the specific requirements of the drug product and the medium in which the dissolution test is conducted. Factors such as the pH of the medium, the temperature, and the stirring speed can all influence the dissolution rate and, consequently, the value of Q.
In summary, the term "Q" in dissolution testing is a pivotal parameter that determines the acceptability of a drug product based on its ability to release the specified amount of API within a given time frame. It is a critical component of the dissolution profile, which is used to assess the quality, consistency, and therapeutic equivalence of pharmaceutical products.
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The USP Dissolution testing involves three stages and the acceptance criteria are defined for each stage as a function of a quantity Q, a percentage of the label value that is established for each drug product in its monograph. ... Probability of acceptance of the dissolution test (Pa), e. g.read more >>