Abstract
Accurate quantification of all 20 proteinogenic amino acids (AAs) is critical for the quality control of total parenteral nutrition (TPN) formulations containing complex excipient matrices. This study presents a rapid and validated reversed-phase high-performance liquid chromatography (RP-HPLC) method employing pre-column derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) and fluorescence detection (FLD) for the simultaneous determination of AAs. Complete baseline separation of all 20 AAs was achieved within 18 minutes, with a total analytical run time of 25 minutes on a conventional HPLC system. The method was validated in accordance with ICH Q2(R2) guidelines, demonstrating excellent linearity (R2 > 0.999), high sensitivity (limits of detection = 0.02-0.16 μmol/L), precision (relative standard deviation< 2%), accuracy (recoveries = 98.2-101.7%), specificity (no matrix interference) and robustness under deliberate minor variations in chromatographic conditions. These findings confirm the method's reliability and suitability for pharmaceutical quality control. This RP-HPLC-FLD method provides a rapid, cost-effective and reproducible alternative to LC-MS for routine quality control of TPN formulations in pharmaceutical laboratories.