Development and Validation of an RP-HPLC/DAD Method for Luteolin Quantification in Novel Hydroxyapatite Nanocomposites

Abstract Calcium hydroxyapatite (HAp) is widely used in medical and aesthetic fields for bone repair and dermal applications. Luteolin (LUT), a flavonoid with anti-inflammatory and antioxidant properties, may enhance the therapeutic potential of HAp for collagen production into the skin. The main aim of this paper was to develop and validate a simple and reliable RP-HPLC/DAD method for quantifying LUT in HAp nanocomposites. The synthesis of hydroxyapatite nanoparticles (n-HAp) was performed via precipitation method. To obtain the novel nanocomposites, n-HAp was associated with LUT by the wet method using ethanol into a SpeedMixer®, followed by drying into an oven at 35ºC for 48 hours. The RP-HPLC/DAD method was developed for quantifying the LUT incorporation efficiency. The validation parameters assessed included selectivity, linearity, limits of quantification (LOQ) and detection (LOD), precision, accuracy, robustness, and sample stability. The novel nanocomposites n-Hap-LUT were successfully prepared using the proposed method. The incorporation efficiency demonstrated high values of 82.90% and 95.16% for nHAp-LUT samples. Thus, the RP-HPLC/DAD method was appropriate for quantifying LUT in novel dermal aesthetic products for collagen production and may be further used for design and quality control of novel collagen biostimulation technologies.