Erythrosine-loaded nanoemulsion prepared by low-energy method: advanced characterization, in vitro release, and HET-CAM ex vivo evaluation

Erythrosine, a naturally derived dye, is extensively employed in the food and pharmaceutical industries; however, its low stability in aqueous media limits broader technological applications. Therefore, the development of erythrosine-loaded nanoemulsions has emerged as a strategy to overcome this limitation. This study aimed to develop and characterize erythrosine-loaded nanoemulsions, as well as to evaluate their ex vivo biocompatibility and performance. Nanoemulsions were formulated using different surfactants, and the formation region was analyzed using a pseudo-ternary phase diagram. Physicochemical, structural, and photophysical characterizations were performed, along with an evaluation of the erythrosine release profile. The nanoemulsion was developed using a low-energy method with erythrosine incorporated into the organic phase and a high association rate. The formulation remained stable for 90 days under various environmental conditions, with an estimated shelf life of 2.4 months. Morphological characterization confirmed the formation of homogeneous nanoemulsions. To optimize the application, the formulation was gelled using 23% Pluronic® F-127. Rheological and texture analyses showed results consistent with nanostructured materials described in the literature. The release profile of erythrosine from the gelled nanoemulsion exhibited sustained release following Higuchi kinetics, a characteristic model for gel-based release systems. The HET-CAM assay indicated a biocompatible range and supported further investigation of the nanoemulsion system in antiangiogenic studies. These findings highlight nanoemulsions as a promising strategy to enhance the technological application of erythrosine.