Attaching a self-complementary zwitterionic supramolecular binding site to the amino groups of polyethyleneimine leads to a pH switchable hydrogel as dimerization of the zwitterions introduces additional crosslinks between the polymer chains. This gel responds to both the addition of either acid or base, as only the zwitterion can self-assemble but neither the protonated or deprotonated form.

The title compound, C(9)H(10)N(2)O(4)·H(2)O, exists as a zwitterion with a deprotonated carboxyl group and a protonated amino group. The crystal packing is stabilized by N-H⋯O and O-H⋯O hydrogen bonds, building sheets parallel to the (001) plane. The absolute configuration was deduced from the synthetic pathway.

The title compound, C(11)H(9)N(3)O(4)S, crystallizes with two mol-ecules in the asymmetric unit; each mol-ecule exists as a zwitterion in the solid state. Inter-molecular N-H⋯N hydrogen bonds link the mol-ecules into chains. Weak C-H⋯O inter-actions further stabilize the crystal structure.

A camphor based chiral phosphonium hydrido borate zwitterion was synthesised and successfully applied in the enantioselective hydrogenation of imines with selectivities up to 76% ee. The high stability of the novel chiral FLP-system enables effective recycling of the metal-free catalyst.

A new approach to immobilize zwitterionic molecules rapidly and highly efficiently on a gold surface applies aniline-based electrodeposition. The zwitterion-functionalized antifouling surface enables a decrease of the adsorption of non-specific proteins by 95% from fetal bovine serum (FBS, 10%).

In the title zwitterion, C17H12N2O2, the dihedral angle between the benzene ring and naphthalene ring system is 11.76 (7)° and an intra-molecular N-H⋯O hydrogen bond exists. In the crystal, molecules are linked via pairs of C-H⋯O hydrogen bonds, forming inversion dimers.

Quasi-Solid-State Sodium-Ion Capacitors In article number 2300068, Fangyuan Hu and co-workers develop a novel gel polymer electrolyte that containing 3-(1-vinyl-3-imidazolio) propanesulfonate zwitterion, which shows the dual effects of fast desolvation near interface rapid ion transport through to increase kinetics anions cations, enabling high energy density stable cycling performance for sodi...

In the crystal structure of the title zwitterion, C5H11N5S, mol-ecules are linked via N-H⋯N hydrogen bonds, forming zigzag chains propagating along [010]. The chains are linked by C-H⋯S hydrogen bonds, forming two dimensional networks lying parallel to (001).