Abstract

FORMULATION AND EVALUATION OF STINGING NETTLE (URTICA DIOICA) EXTRACT-LOADED PLGA NANOPARTICLES FOR ANTIALLERGIC THERAPY

Mamatha B. C., Hemalatha K. P.*, Mancy S. P., Vijaykumar S.

ABSTRACT

The present investigation aimed to develop and evaluate poly(lactic-co-glycolic acid) (PLGA) nanoparticles encapsulating Urtica dioica (stinging nettle) extract for potential antiallergic therapy. Urtica dioica has well-documented anti-inflammatory and antihistaminic activities, attributed to its rich content of flavonoids, phenolic acids, and lectins. However, its therapeutic use is limited by poor solubility, rapid degradation, and low bioavailability. In this study, PLGA nanoparticles were prepared using the solvent evaporation technique, optimizing parameters such as polymer and surfactant concentration via a 3² factorial design. Nine formulations (F1–F9) were prepared and characterized for particle size, zeta potential, polydispersity index (PDI), entrapment efficiency (%EE), surface morphology, and in vitro drug release behavior. The optimized formulation (F5) exhibited a mean particle size of 184.6 nm, zeta potential of −25.3 mV, and %EE of 86.2%. In vitro release studies demonstrated a biphasic release profile with an initial burst followed by sustained release up to 91.3% over 24 hours. The results indicated that PLGA-based nanoencapsulation effectively improved the stability and release profile of Urtica dioica bioactives, suggesting its potential for developing a novel herbal antiallergic nanoformulation with enhanced bioavailability and therapeutic performance.

Keywords: Urtica dioica, PLGA nanoparticles, stinging nettle, antiallergic therapy, solvent evaporation, sustained release.