A Greener Approach to Prepare Natural Deep Eutectic Solvents

Abstract

Natural deep eutectic solvents (NADES) is one of the hottest issues in the field of green chemistry. However, it is possible to make them greener? Herein we propose a new microwave (MW) assisted preparation demanding only seconds. The MW‐NADES were challenged with those obtained by the classical Heating & Stirring procedure in terms of green analytical metrics and physical parameters. Indeed, the following analytical applications were tested: a) extraction media for phenolics and alkaloids from plant, b) enhancers for electrochemical detection of phenolic compounds. Our results demonstrate outstanding environmental advantages as the dramatic decrease of synthesis time (the shortest time to date, 60 minutes to 20 seconds) and energy consumption (650 times lower). The analytical performance and physicochemical parameters were comparable with the traditional NADES.

Application of natural deep eutectic solvents to extract ferulic acid from Ligusticum chuanxiong Hort with microwave assistance

“…28,29 NADES are usually mixtures that consist of two or more kinds of naturally occurring and biodegradable components (such as glucose, an organic acid, polyalcohol and choline chloride) 30,31 and can be prepared by green and fast methods such as heating 32,33 and microwave-assisted methods. 34 The physicochemical properties of NADES are similar to those of ionic liquids. But compared with ionic liquids, NADES provide many advantages, such as readily available components, simple preparation, low toxicity and tunability.…”

Innovative Extraction Techniques Using Deep Eutectic Solvents and Analytical Methods for the Isolation and Characterization of Natural Bioactive Compounds from Plant Material

“…Based on the results confirmed by Hsieh et al, sonification with a frequency of 40 kHz at room temperature (RT) and a sonification time of up to 5 h should be used to produce clear and colorless liquids [64]. Recently, in a short communication by Gomez et al, a faster, simpler, cheaper and more environmentally friendly method of DES synthesis, based on microwave irradiation was described for the first time [65]. Microwave-assisted technology enabled the authors to generate three different DES, with physical-chemical properties comparable to those produced by conventional method in only 20 s and a significant reduction in total energy consumption.…”

Natural Deep Eutectic Solvents for the Extraction of Phenyletanes and Phenylpropanoids of Rhodiola rosea L.

“…All NADES were prepared according to the reported method [61]. Lactic acid (L) and hydrogen bond donor (HDB) glucose (G) or fructose (F) at the respective molar ratio were directly weighed, and the mixture was stirred in the sealed flask at 50 • C for 90 min until a homogeneous transparent colourless liquid was formed.…”