In Vitro Release Performance of Naproxen Sodium/Acetaminophen Pediatric Suspensions Using a Mini-Paddle Apparatus and USP Paddle Apparatus
Year: 2026
Type: article
Abstract: Background: Fixed-dose pediatric suspensions of naproxen sodium (NAP, 25 mg/mL) and acetaminophen (ACE, 20 mg/mL) are widely prescribed for childhood pain and fever, but lack official compendial dissolution monographs. Objective: To evaluate in vitro dissolution of three generic pediatric suspensions (G1–G3) against the reference product (Febrax®, R), comparing the discriminatory sensitivity of a mini-paddle apparatus versus the standard USP paddle apparatus. Methods: Dissolution was conducted in pH 6.8 phosphate buffer (37.0 ± 0.5 °C, 75 rpm) using a mini-paddle apparatus (200 mL, 2 mL dose) and USP Apparatus 2 (500 mL, 5 mL dose), maintaining identical 0.25 mg/mL NAP and 0.20 mg/mL ACE concentrations (n = 12). First-derivative spectrophotometry quantified NAP (243 nm) and ACE (253 nm). Model-independent metrics (Q60, MDT, DE) were analyzed by ANOVA with Dunnett's test. Results: Over 85% of both drugs dissolved within 15 min across all formulations, omitting f2 similarity calculations. Model-independent metrics revealed that the standard USP paddle apparatus detected statistically significant differences (p < 0.05) in 88.89% of comparisons against reference R, whereas the mini-paddle apparatus detected differences in only 38.89%. Conclusions: The standard USP paddle apparatus provides superior discriminatory sensitivity over the mini-paddle system for quality control and post-marketing surveillance of pediatric suspensions.
Language: English
Subfield: Analytical Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W7204198212