Encapsulation of Highly Volatile Fragrances in Y Zeolites for Sustained Release: Experimental and Theoretical Studies

Abstract

Volatility is an inherent fragrance attribute and typically implies a reduced perception over time. One possibility to elongate odor perception is utilizing controlled fragrance-delivery systems. Herein, the Y type of faujasite with different extraframework cations (abbreviated as ZY, where Z represents Na + , Ca 2+ , or La 3+ ) was examined as potential carriers for fragrance entrapment and delivery. D-Limonene (Lim) and linalool (Lol) as model fragrances were loaded in the pore space of Y zeolites, yielding composites FG@ZY (FG = Lim, Lol). It was found that the fragrance release profiles correlate highly with the cationic species located in the nonframework. The retention of fragrances in matrices increases in the order NaY < CaY < LaY for either limonene or linalool. Interestingly, the release rate of limonene was significantly slower than that of linalool when encapsulated in the same zeolite, although neat limonene has a much higher saturated vapor pressure than linalool. For instance, the total fraction of aroma released from Lim@LaY over 30 days was about 10%, while the value was ∼20% for Lol@LaY. Based on the density functional theory calculations, the above results could be well rationalized by the electrostatic attraction and shape selectivity of microporous matrices to the dopant molecules.

Encapsulation of Eucalyptus largiflorens Essential Oil by Mesoporous Silicates for Effective Control of the Cowpea Weevil, Callosobruchus maculatus (Fabricius) (Coleoptera: Chrysomelidae)

“…In this study, the fumigant persistence of E. largiflorens essential oil was improved by encapsulation in MCM-41 and Zeolite 3A. Although both physical and chemical mechanisms may be considered in loading and releasing essential oils from porous materials, research is often focused on physical means due to the presence of several nanopores in these materials [ 31 , 66 ]. For example, Milićević et al [ 67 ] indicated that zeolite adsorbs the droplets of clove bud essential oil due to its porosity; the insecticidal, antifungal, and antibacterial effects of essential oils were augmented by loading in this porous material.…”

“…Recently, there has been growing interest in the application of mesoporous nanoparticles, such as zeolites and MCM-41, ranging from adsorption to active ingredient delivery [ 30 ]. Nanoencapsulation of highly volatile fragrances, such as essential oils and their components, in zeolites and MCM-41 for controlled release and enhancement of their durability is one of the recent promising applications of mesoporous materials [ 31 , 32 ]. For example, the antibacterial activity of film nanocomposite made from zein film and cinnamon essential oil was significantly prolonged by loading the essential oil in MCM-41 for application in long-term packaging [ 33 ].…”

Essential Oils Encapsulated in Zeolite Structures as Delivery Systems (EODS): An Overview

“…Zeolites not only offer a stable framework, specific ion exchange properties, and adsorption capacities, but their porous nature and inherent pH-sensitive properties also enable the entrapment and selective release of the encapsulated compounds [ 61 , 97 , 99 , 100 , 101 ]. This effect could be beneficial for acid tumor environments, topical applications, or textile applications.…”

Triggered and controlled release of active gaseous/volatile compounds for active packaging applications of agri‐food products: A review

“…They also found that zeolite had lower encapsulation capacity than MOFs (Basolite C300 and Basolite A520). Zeolites with different framework cations (Na + , Ca 2+ , or La 3+ ) were investigated as potential carriers for limonene and linalool entrapment and delivery (Li et al., 2020). The retention of volatiles in the matrices increases in the order Na > Ca > La for either limonene or linalool.…”