Construction and application of thrombin-activated fluorescence-SERS dual-mode optical nanoprobes.

Thrombin (TB) plays a key role in the pathological and physiological coagulation of diseases. In this work, a TB-activated fluorescence-surface-enhanced Raman spectroscopy (SERS) dual-mode optical nanoprobe (MRAu) was constructed by linking rhodamine B (RB)-modified magnetic fluorescent nanospheres with AuNPs through TB-specific recognition peptides. In the presence of TB, the polypeptide substrate could specifically be cleaved by TB, resulting in the weakening of SERS hotspot effect and the reduction of Raman signal.

Alkaloids constituents from the roots of (Cav.) Trin. ex Steud. with their cytotoxic activities.

Two new alkaloids, phranisines AB (), along with two known compounds, N-p-Coumaroyl serotonin () and N-p-coumaroyl-tryptamine (), were isolated from the roots of . The structures of were established on the basis of extensive spectroscopic. The absolute configuration of compounds were identified through quantum-chemical electronic circular dichroism (ECD) calculation compared with their experimental CD.

Cloud-point temperature and liquid-liquid phase separation of supersaturated lysozyme solution.

The detailed understanding of the structure of biological macromolecules reveals their functions, and is thus important in the design of new medicines and for engineering molecules with improved properties for industrial applications. Although techniques used for protein crystallization have been progressing greatly, protein crystallization may still be considered an art rather than a science, and successful crystallization remains largely empirical and operator-dependent. In this work, a microcalorimetric technique has been utilized to investigate liquid-liquid phase separation through measuring cloud-point temperature T(cloud) for supersaturated lysozyme solution.