calixarenes and benzeneboronic-acid

Chiral metal-organic complexes hold great promise as new functional materials that exhibit unique stereochemical and optical properties. Here, we report the formation of optically pure pillar[5]arene-based platinum chiral metallacycles. By coordination with 60° and 90° Pt(II) acceptors, planar chiral platinum triangles were self-assembled efficiently and characterized by multiple spectroscopic techniques. Optical studies indicated that these metallacycles had chiral properties:

Topics: Boronic Acids; Calixarenes; Coordination Complexes; Fluorescent Dyes; Models, Molecular; Molecular Structure; Organoplatinum Compounds; Pyridines; Spectrometry, Fluorescence; Stereoisomerism

A nanocarrier (p(6SRA-5B)) for glucose-controlled insulin delivery consists of sulfonated resorcinarenes (SRA) that are assembled into a spherical shell and are attached to each other with phenylboronate linkers. p(6SRA-5B) is stable in water and blood plasma at normal glucose concentrations. At high glucose levels (>5 mM), p(6SRA-5B) dissociates into SRA and phenylboronates through competitive interaction with excess glucose. Insulin was successfully encapsulated into the cavity of p(6SRA-5B) and its release was investigated in water and blood plasma by NMR, UV, CD, and fluorescence spectroscopy. The results show that the dissociation of the nanocarrier and the insulin release occurs with an increase in glucose concentration. At 5 mM glucose, the nanocarrier is stable, and the insulin release does not exceed 10 %. Increasing the glucose concentration to 7.5-10 mM results in a 40-100 % insulin release. p(6SRA-5B) is thus a promising insulin nanocarrier for the treatment of type 1 diabetes.

Topics: Boronic Acids; Calixarenes; Diabetes Mellitus, Type 1; Drug Carriers; Drug Delivery Systems; Drug Liberation; Glucose; Humans; Insulin; Phenylalanine; Polymers; Sulfonic Acids