Encapsulation of the Ethylene Inhibitor 1-Methylcyclopropene by Cucurbit[6]uril

Abstract

1-Methylcyclopropene (1-MCP) is an excellent safe and commercially available ethylene antagonist for the preservation of horticultural products. However 1-MCP has to be stored in absorbents due to its gaseous and unstable characteristics. In this paper cucurbit[6]uril (CB[6]) was used as the absorbent to encapsulate 1-MCP, and the resultant inclusion complex was characterized by IR, powder X-ray diffraction, thermal analysis, and fluorescent spectra. The effects of encapsulation conditions on the formation of inclusion complex were also investigated. The amount of 1-MCP encapsulated by CB[6] was about 4.5% by weight when the initial concentration of 1-MCP, encapsulation temperature, CB[6] concentration, and encapsulation time were set at 75 mL/L, 20 °C, 30 mM, and 8 h, respectively. Furthermore, the release of 1-MCP from the complex can be realized with different solutions such as sodium bicarbonate, benzoic acid, and distilled water. CB[6] can be used as an excellent absorbent for encapsulation of 1-MCP.

Synthesis and Characterization of Cucurbit[6]uril Supported Copper Oxide Nanoparticles, CuO@CB[6]: Application as Nanocatalyst for the Synthesis of 2H‐indazoles

“…The PXRD spectra of CB[6] and CuO@CB[6] nanocomposite are shown in Figure . The PXRD spectrum of CB[6] showed a characteristic diffraction peak at 2θ=13.9°, 15.1°, 17.8°, 20.9° . Furthermore, the PXRD spectrum of CuO@CB[6] exhibited characteristic diffraction peaks at 2θ=32.49°, 35.94°, 38.57°, 48.47°, 53.31°, 61.30°, 65.79°, 66.24°, 71.56° and 75.40° corresponding to the planes (110), (‐111), (111), (‐202), (020), (‐113), (‐311), (220), (311), and (‐222), respectively (JCPDS card number 45–0937), which confirms the presence of pure CuO nanoparticles…”

“…The first weight loss (∼5%) was observed around 150 °C which might be due to dehydration. The second weight‐loss ladder appeared at 280 °C which may be due to self‐decomposition of nanocomposite …”

1-Methylcyclopropene (MCP)-Containing Cellulose Paper Packaging for Fresh Fruit and Vegetable Preservation: A Review

“…They synthesized the CD-based carbonate nanosponges from native β-CD and active carbonyl compounds, and the 1-MCP included in β-CD nanosponges showed superior antiethylenic performances in long-lasting cut flowers in comparison with α-CD complex products, such as SmartFresh, due to the increased inner cavity (Seglie et al 2011;Seglie et al 2012). Zhang et al (2011) reported a study of encapsulating 1-MCP by Cucurbit[6]uril, a barrel-like macrocyclic molecule, which is prepared from the cheap starting materials glycoluril and formalin, and has the similar cavity size to α-CD (Fig. 6), as the absorbent to encapsulate 1-MCP.…”

A microcapsule oil dispersion for the controlled release of 1-methylcyclopropene in an open environment

“…8,9 However, 1-MCP is chemically unstable under normal environmental conditions and presents an explosive hazard when compressed. 10 Microcapsule formulations in biodegradable carriers, such as starch, have been widely developed and used in agriculture to improve pesticide utilization and reduce environmental pollution. [11][12][13] Hence, the commercial formulation of 1-MCP constitutes microcapsule granules with a-cyclodextrin, called 1-MCP microcapsule granules (1-MCP/MCG), 14,15 which can release the 1-MCP gas as soon as they come in contact with water.…”