Supramolecular Control on the Optical Properties of a Dye-Polyelectrolyte Assembly

Application of sodium sulfobutylether-β-cyclodextrin based on encapsulation

Sodium Sulfobutylether-β-cyclodextrin (SBE-β-CD) is a derivative of β-cyclodextrin, characterized by its stereo structure, which closely resembles a truncated cone with a hydrophobic internal cavity. The solubility of insoluble substances within the hydrophobic cavity is significantly enhanced, reducing contact between the guest and the environment. Consequently, SBE-β-CD is frequently employed as a co-solvent and stabilizer. As the research progresses, it has been observed that the inclusion of SBE-β-CD is reversible and competitive. Besides, some inclusion complexes undergo distinct physicochemical property alterations compared to the guests. Additionally, certain guests exhibit varying inclusions with SBE-β-CD at different concentrations. These features have contributed to the expanding applications. SBE-β-CD finds widespread application in pharmaceutics as a protective agent and pKa regulator, in pharmaceutical analysis as a chiral substance separator, and in biomedical engineering for encapsulating dyes and modifying sensors. The article will elaborate in detail on the physicochemical properties of SBE-β-CD, encapsulation principles, and factors influencing the formation of inclusion complexes. Furthermore, the review focuses on the application of SBE-β-CD through encapsulation in pharmaceutics, pharmaceutical analysis, and biomedical engineering. Finally, the prospects and potential applications of SBE-β-CD are discussed.

Ratiometric detection of polymyxin B based on the disaggregation of pyrenyl nanoassemblies in 100% aqueous media

Polymyxin B (PMB) was an antibiotic with highly effective antibacterial effect but narrow safety interval, and its residues in food had attracted widespread attention. It was important to develop an accurate method for the rapid detection of PMB in animal foods. In this work, we had established a ratiometric sensing system based on the formation of supramolecular assemblies of pyrenyl probes, which were driven by the synergy of noncovalent forces such as multiple-electrostatic and π-π stacking interactions. Compared with the traditional fluorescence detection based on the single wavelength change, the present approach showing two-wavelength fluorescence response could reduce the interference of other factors making the experimental results more accurate. The sensor exhibited high sensitivity and selectivity with a low detection limit (28.3 nM). This method could be used to realize visual detection and had a visual detection limit of 1 μM. As we had learned yet, this was the first ratiometric sensor for PMB detection in aqueous solution. We believed all our preliminary would not only provide a complementary strategy for the detection of PMB, but also develop some new ideas for the construction of sensors for rapid antibiotic detection.