Artemisinin is a sesquiterpenoid lactone peroxide, known for its potent antimalarial activity that can be extracted from Artemisia annua L. This compound is only sparingly soluble in water, making its extraction using environmental-friendly and non-toxic aqueous solvents difficult. In the attempt to overcome this limitation, hydrotropes, which are a class of compounds that can assist in increasing the solubility of hydrophobic solutes in water, were investigated in this work. In particular, the hydrotropic capability of ionic liquids (ILs) on the aqueous solubility of artemisinin was studied. The effects of IL concentration and anion nature of 1-butyl-3-methylimidazolium-based ILs on the solubility of artemisinin at 303.2 K in water were evaluated. It is here shown the excellent capacity of ILs containing thiocyanate or dicyanamide anions to enhance the solubility of artemisinin in aqueous media, with a magnitude comparable to that obtained with the best organic solvents. Furthermore, solvatochromic parameters of the ILs aqueous solutions were also measured and combined with COSMO-RS and the cooperative hydrotropy model to establish relations between the artemisinin solubility enhancement and the solvent characteristics. The solubility enhancement of artemisinin is favored by the apolarity of the medium and the lower hydrogen-bond acceptor character of the hydrotrope.

青蒿素是一种倍半萜内酯过氧化物，以其强大的抗疟活性而著称，可从青蒿中提取。。该化合物仅微溶于水，因此很难使用环保且无毒的水性溶剂进行萃取。为了克服这一限制，在这项工作中研究了水溶助长剂，水溶助长剂是一类有助于增加疏水性溶质在水中的溶解度的化合物。特别是，研究了离子液体（ILs）对青蒿素水溶性的亲水性。评估了IL浓度和1-丁基-3-甲基咪唑鎓类ILs的阴离子性质对青蒿素在303.2 K水中的溶解度的影响。此处显示了含有硫氰酸根或双氰胺阴离子的IL具有增强青蒿素在水性介质中的溶解度的出色能力，其程度可与使用最佳有机溶剂获得的程度相媲美。此外，还测量了ILs水溶液的溶剂溶变色参数，并将其与COSMO-RS和协同亲水性模型相结合，以建立青蒿素溶解度增强与溶剂特性之间的关系。培养基的非极性和水溶助长剂的较低氢键受体特性有利于提高青蒿素的溶解度。