Gamma scintigraphy is widely used in model validation for drug delivery systems because it provides direct, real-time, and quantitative visualization of a formulation’s in vivo behavior, which can be compared to predictions from in vitro or computational models.

Summary of Gamma Scintigraphy in Model Validation

Direct In Vivo Evidence: Gamma scintigraphy tracks the movement, deposition, and release of radiolabeled drug products within the body, allowing researchers to see if the formulation behaves as models predict under physiological conditions.

Quantitative Comparison: The technique enables precise measurement of where and when a drug is released or deposited, supporting quantitative validation of model outputs such as transit times, release profiles, and regional deposition.

Assessment of Critical Parameters: It helps validate key model assumptions, such as the effect of food, pH, or patient technique on drug delivery, by providing real-world data that can confirm or challenge in vitro or computational predictions.

Integration with PK Data: When combined with pharmacokinetic sampling (pharmacoscintigraphy), gamma scintigraphy links observed in vivo events (e.g., drug release or absorption) to systemic drug levels, further validating mechanistic models.

Supports Regulatory Confidence: Because it provides robust, non-invasive, and reproducible in vivo data, gamma scintigraphy is often considered a gold standard for validating drug delivery models, supporting regulatory submissions and product claims.

In Summary: Gamma scintigraphy bridges the gap between model predictions and actual human outcomes, offering a powerful tool for validating and refining drug delivery models across oral, inhalation, and nasal routes.