ABSTRACT A water‐in‐liquid crystal‐in‐water (W/LC/W) double emulsion was prepared via LC phase transition and homogenization, mixing a liquid crystal and an anionic surfactant solution. The resulting LC double emulsion (LCDE) achieves a balance between electrical double‐layer forces and elastic forces, stabilizing guest aqueous droplets (GADs) within the LC phase. Upon introduction of oppositely charged amphiphilic molecules, electrostatic interactions at the LC/water interface disrupt this balance, releasing the GADs. Furthermore, by exploiting host–guest interactions, the hydrophobic segment of the surfactant is encapsulated within a host molecule possessing a hydrophobic cavity, thereby masking its surface activity. This design transfers the responsiveness of the LCDE to hydrophobic molecules with higher host affinity. Integrated with pregnancy test strips (PTS), the system enables visual quantification and detection of bacteria and on‐demand elimination. The responsive LCDE offers advantages such as low cost, rapid response, and operational portability as a signal carrier for POCT, and holds high potential in applications working as microreactors and artificial cell models, etc.
Chen et al. (Fri,) studied this question.