What the study found
A first-order derivative spectrophotometric method was developed to measure dexamethasone sodium phosphate (DSP) in injectable formulations even when creatinine causes overlapping ultraviolet absorption. The method uses a zero-crossing point, meaning the measurement is taken where the creatinine signal is nullified.
Why the authors say this matters
The authors conclude that this provides a rapid, cost-effective, and eco-friendly alternative for routine quality control of DSP injectables. They also state that it removes the need for complex chromatographic separation techniques.
What the researchers tested
The researchers used distilled water as the solvent and applied a matrix-matching calibration strategy with a constant 1:2 (w/w) DSP:creatinine mass ratio across the concentration range. DSP was measured by first-order derivative spectrophotometry at about 231.3 nm, following ICH Q2 (R1) validation guidance.
What worked and what didn't
The method showed linearity for DSP concentrations from 4.0 to 16.0 μg/mL, with R2 greater than 0.99. Validation showed a mean recovery of 99.85% and precision with RSD below 2%.
What to keep in mind
The abstract does not describe limitations beyond the stated concentration range and formulation context. The findings are limited to the injectable DSP preparations tested under the described matrix-matching conditions.
Key points
- Creatinine interference in DSP injectables was addressed with first-order derivative spectrophotometry.
- DSP was measured at a zero-crossing point near 231.3 nm where the creatinine signal is nullified.
- The method was linear from 4.0 to 16.0 μg/mL, with R2 greater than 0.99.
- Validation gave a mean recovery of 99.85% and precision with RSD below 2%.
- The authors describe the method as an eco-friendly alternative to chromatographic separation for routine quality control.
Disclosure
- Research title:
- Derivative spectrophotometry resolved creatinine interference in DSP injectables
- Publication date:
- 2026-04-02
- OpenAlex record:
- View
- Image credit:
- Photo by CDC on Unsplash · Unsplash License
Get the weekly research newsletter
Stay current with peer-reviewed research without reading academic papers — one filtered digest, every Friday.