A rapid, convenient, and sensitive analytical technique for quantitative analysis of triamcinolone acetonide (TAC) in pharmaceutical nasal spray dosage form using the blue tetrazolium colorimetric reaction and UV spectrophotometric method was developed and validated. Beer’s law of the developed method was proven in the concentration range of 10–40 µg/mL and showed a specific linear relationship with coefficient value R2 = 0.998. The LOQ level was 9.99 µg/mL, with (RSD = 0.26%). From precision assay, RSD values have been obtained for the repeatability and intermediate precision, which were found to be (RSD = 1.65%) and (RSD = 2.01%), respectively, indicating that the method is reproducible. Recovery studies showed mean recoveries in the range of (100.08–103.65 %), meeting the acceptance criteria for accuracy. In addition, we compared the results of the developed method UV–Vis spectrophotometric procedure with those of a well-established official USP analytical procedure (HPLC), and the results showed good agreement. The proposed UV method represents a potential alternative to the official USP analytical assay procedure (HPLC) for estimating TAC in nasal spray forms. Furthermore, it has the potential to be implemented in routine use for rapid qualitative and quantitative determinations for TAC.

Background/Objectives: Vancomycin hydrochloride (HCl) for injection is a vital antibiotic for severe infections. Vancomycin is an indispensable first-line antibiotic for life-threatening infections like methicillin-resistant Staphylococcus aureus (MRSA) bacteremia and serves as a key oral agent for severe Clostridium difficile infection. This makes rigorous quality monitoring essential. Concerns about the efficacy of certain generic vancomycin HCl products have prompted regulatory agencies to increase post-market evaluations to ensure patient safety. Aligned with these efforts, this study aimed to comparatively evaluate the potency and quality of five randomly procured generic intravenous vancomycin HCl products marketed in Saudi Arabia. Methods: Using both microbiological and chemical methodologies as recommended by the US Pharmacopeia (USP) guidelines. Results: The microbiological assay, utilizing the USP “Antibiotics—Microbial Assay” method using Bacillus subtilis ATCC 6633 via the agar diffusion technique, demonstrated a strong linear correlation (R² > 0.98) between inhibition zone diameters and vancomycin concentration. All five tested generics products showed compliance (~ 105%) with USP biological activity standards. For chemical quantification, a High-Performance Liquid Chromatography-Diode Array Detector (HPLC-DAD) method was developed and validated according to ICH Q2(R2) guidance. This method showed excellent linearity (R² = 0.998), accuracy (96.9–102%), and good precision. Conclusions: Both methods confirmed the potency of the tested generics within USP limits. However, minor variations observed between microbiological and chemical results highlight the importance of employing complementary techniques for comprehensive quality assessment. These findings underscore the importance of robust regulatory frameworks and ongoing post-market surveillance to ensure the continued safety, efficacy, and availability of quality-assured generic antibiotics in the Saudi market.