Curcumin (CUR), a polyphenol chemical extracted from the rhizomes of the Zingiberaceae plant Curcuma longa, is the main element in spices like turmeric, curry, and mustard, and is widely used as food coloring. CUR impacts various molecular and metabolic pathways due to its broad molecular targets; namely, CUR targets transcription factors, receptors, kinases, cytokines, enzymes, and growth factors. CUR is also believed to have medicinal promise, as the chemical is believed to have anti-inflammatory, antioxidant, antimicrobial, antimutagenic, and antitumor effects by affecting cell cycle, apoptosis, invasion, angiogenesis, proliferation, and metastasis by down-regulating targets in its signaling pathway.
CUR is used in biodegradable polymeric nanoformulation to treat cancer due to its ability to chemosensitize colon cancer cells and synergize with other anticancer medications. Chemotherapy often uses anticancer drugs to attain therapeutic concentrations in cancer tissue, but this results in widespread contamination and a lack of specificity, which can cause side effects. To counteract this, cancer therapy utilizes biodegradable polymeric nanoparticles (NPs), organometallic, and carbon-based chemicals. Despite their effectiveness,no reports exist that have discussed an efficient reversed-phase high-performance liquid chromatography (RP-HPLC) approach that can simultaneously estimate CAP and CUR in plasma and nanoformulation. With precise drug concentration estimates, the necessary therapeutic activity of any medicine can be determined; as such, it is important to use an analytical approach when analyzing drug compositions.
In this study, a fast and specific RP-HPLC method was designed and validated, employing an isosbestic point (or a wavelength, wavenumber or frequency at which the total absorbance of a sample does not change during a chemical reaction or a physical change of the sample) (2). This technology was chosen for its drug delivery application and synergistic effects of CAP and CUR; according to the researchers, no HPLC approach has been documented to estimate and quantify both medicines simultaneously. The technology was verified using ICH Q2 R1 criteria, which discusses the validation of analytical procedures (3). A sensitive and exact analytical method was required; as such, an experimental design was employed.
Quality by design (QbD) is a risk-based scientific approach to designing analytical procedures for continuous improvement, focusing on improved performance, robustness, and flexibility. If analytical procedures are not strong, redeveloping, validating, and transferring them can be time-consuming. As such, this approach was used to optimize and validate this newly made analytical approach.
The mobile phase used for the chromatographic separation was methanol: 0.1 % orthophosphoric acid (80:20), and the conditions were 1 mL/min flow rate and 332 nm. Shim-pack Solar C18 (4.6 × 250 mm, 5 μm) HPLC column was used for this purpose. With a correlation coefficient value >0.999, the created technique was determined to be linear across the concentration range of 0.25–16 μg/mL. The approach that was created was strong, accurate (with a recovery rate of 91.85–106.53%), and precise (with a relative standard deviation of < 2.0%). For CAP, the corresponding limits of detection and quantification were determined to be 0.02 and 0.08 μg/mL, whereas for CUR, they were 0.08 and 0.12 μg/mL, respectively. By ICH standards, the proposed approach was also tested in human plasma for validation.
Tests were also conducted on the stress degradation and the established method's applicability to biodegradable nanoformulation. In the presence of degradation products, there was a good separation of drug peaks. The QbD-based model was shown to be significant after a deliberate adjustment was assessed. Overall, the QbD methodology led to a more accurate procedure, producing consistent, reliable, and high-quality data that accurately quantifies CAP and CUR in bulk and nanoparticulate systems.
(1) Patil, C.; Naik, P.; Mallamma, T.; Goudanavar, P. Exploring the Potential of a Quick and Simultaneous DoE-Based Stability Indicating Novel RP-HPLC Method for the Estimation of Capecitabine and Curcumin in Biodegradable Nanoparticles and Human Plasma. J. Chromatogr. B 2025, 1264, 124731. DOI:
(2) Isosbestic Point. Gold Book 2025.
(3) Validation of Analytical Procedures: Text and Methodology. International Conference on Harmonization 2005.
