Dodecaborate anions of the type B₁₂X₁₂²⁻ and B₁₂X₁₁Y²⁻ (X=H, Cl, Br, I and Y=OH, SH, NH₃⁺, NR₃⁺) form strong (K_a up to 10⁶ L mol⁻¹, for B₁₂Br₁₂²⁻) inclusion complexes with γ‐cyclodextrin (γ‐CD). The micromolar affinities reached are the highest known for this native CD. The complexation exhibits highly negative enthalpies (up to −25 kcal mol⁻¹) and entropies (TΔS up to −18.4 kcal mol⁻¹, both for B₁₂I₁₂²⁻), which position these guests at the bottom end of the well‐known enthalpy‐entropy correlation for CDs. The high driving force can be traced back to a chaotropic effect, according to which chaotropic anions have an intrinsic affinity to hydrophobic cavities in aqueous solution. In line with this argument, salting‐in effects revealed dodecaborates as superchaotropic dianions.

Autofluorescence of aldehyde-fixed neural tissue often complicates the use of fluorescence microscopy. Background fluorescence can be notably reduced or eliminated by irradiation with light before treatment with fluorescence probes, resulting in a higher contrast without adversely affecting the staining probabilities.

The host–guest chemistry of large-ring cyclodextrins (LRCDs) has been largely unexplored due to the lack of suitable guest molecules that bind with significant affinities to enable potential applications. Herein, we report their complexation with dodecaborate anions (B₁₂X₁₂ ²⁻), a novel class of guest molecules. The binding constants of the inorganic guests (10⁴–10⁶ M⁻¹) allow their classification as the first tight binders for LRCDs.