Zwitterionic Polymer-Based Nanoparticles Encapsulated with Linalool for Regulating Central Nervous System

Abstract

Aromatherapy is widely used in the treatment of diseases of the central nervous system, such as depression and anxiety. However, the rapid and uncontrolled release of aroma weakens the effects of aromatherapy. In this study, zwitterionic polymer-based nanoparticles encapsulated with linalool were prepared to improve the regulation of the central nervous system. First, the nanoparticles were modified with positive charges to adhere to the surface of silk via electrostatic interactions between the cationic nanoparticles and anionic silk. Besides, the fragrance was sustainably and controllably released from the nanoparticles. The effects of polymerization degree, polymer structure, and zeta potential on encapsulation efficiency, adhesion efficiency, and release profiles of linalool were then explored. The results showed that the linalool-encapsulated nanoparticles had the best performances of encapsulation, adhesion and release of fragrance when the polymerization degrees of hydrophilic block and hydrophobic block were 20 and 5, respectively. In addition, open field tests evaluated the regulation of nanoparticles on the central nervous system at the behavioral level. Measurements of dopamine, acetylcholine, and γ-aminobutyric acid expressions explored the mechanism of moderating effects on the central nervous system at the molecular level.

Evolution and Emerging Trends in Depression Research From 2004 to 2019: A Literature Visualization Analysis

“…Physical exercise can promote molecular changes that lead to a shift from a chronic pro-inflammatory to an antiinflammatory state in the peripheral and central nervous system (72). Aromatherapy is widely used in the treatment of central nervous system disorders (73). By activating the parasympathetic nervous system, qigong can be effective in reducing depression (74).…”

Amphiphilic Graft Copolymers for Time-Delayed Release of Hydrophobic Fragrances

“…Lu et al applied poly­(hexyl methacrylate)- block -poly­(carboxybetaine) with an arginine end group that was able to encapsulate linalool in aqueous solution by hydrophobic interactions with the hexyl side chain, and the arginine end group allowed deposition onto silk fibers by electrostatic interactions. At pH = 7 and pH = 8typical conditions during washing processesthe fragrance-loaded nanocapsules remained on the fibers, whereas at pH = 5the pH of skin after transpirationthe release of the fragrance was triggered . Ternat et al.…”

pH‐activated polymeric profragrances for dual‐controllable perfume release

“…However, such precursor strategy is significantly limited by unreliable controllability, inadequate reproducibility, and inefficient release. Current research studies mainly stress on direct physical encapsulation to construct nanoscale profragrances with nanocarriers involving polymers, 8‐16 macromolecules, 17,18 inorganic materials, 19,20 and other functional nanocarriers 21‐25 . With the assistance of these nanocapsules, profragrances behave more temperate scent and prolonged retention effect than free fragrances.…”