Researchers have introduced a new approach to the separation of organic compounds. In their process, a ‘host compound’ recognizes the desired ‘guest molecules’, not only in solution, but also when the host and mixtures of competitive guest are milled together in the solid state…. Researchers have introduced a new approach to the separation of organic compounds. In their process, a ‘host compound’ recognizes the desired ‘guest molecules’, not only in solution, but also when the host and mixtures of competitive guest are milled together in the solid state.