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Vesicular particles based on inclusion complexes between BPB and γ-HB-β-CDs were prepared and characterized for the first time. The morphologies and sizes were confirmed by transmission electron microscopy (TEM), scanning electron microscope (SEM), and dynamic light scattering (DLS). Particularly, these vesicular particles exhibiting clearly fluorescent dots observed by laser confocal scanning microscopy (LCSM) could be alternative candidates as fluorescent probes and labels being applied to cellular staining, labeling, bio-mimicking and drug delivery. The ultraviolet, fluorescence, and nuclear magnetic resonance (NMR) measurements confirmed the existence of stable 1:1 BPB-γ-HB-β-CD complexes in the system. The vesicular particles were assumed to be constructed by orderly self-aggregates of these inclusion complexes. [ABSTRACT FROM AUTHOR]

A new amphiphilic cyclodextrin derivative 2-O-(hydroxypropyl-N,N-dimethyl-N-dodecylammonio)-β-cyclodextrin (2-HPDMDA-β-CD) was prepared and characterized by surface tension, electrical conductivity, dynamic light scattering, transmission electron microscopy (TEM) and steady-state fluorescence. 2-HPDMDA-β-CD was found to be a fine surfactant with a smaller critical micelle concentration (1.21 mM) value than that of dodecyltrimethylammonium chloride. TEM showed that 2-HPDMDA-β-CD could form two kinds of spherical aggregates in solution. The smaller one showed little concentration dependence while the larger one showed relatively strong concentration dependence. 2-HPDMDA-β-CD could be a fine host compound in molecular recognition with two functional spaces of the cyclodextrin cavity and micelles. [ABSTRACT FROM AUTHOR]

The effect of NaBr on the interaction between alkyltrimethylammonium bromide (CnTAB (n = 14 for TTAB and 16 for CTAB)) and ss-CD was studied by surface tension method. The first decrease in the γcmc of TTAB/ss-CD in the presence of NaBr mainly due to the elongated effective chain length of the hydrophobic part of the TTAB/ss-CD complexes; while the increase in the γcmc of both of the TTAB/ss-CD and CTAB/ss-CD in the presence of NaBr could be attributed to the close pack of CnTAB at the air/water interface. [ABSTRACT FROM AUTHOR]

The dispersion effect of five cyclodextrins (CDs) on carbon nanotubes (CNTs) was studied. 2-HB-β-CD is the most efficient dispersing agent. The dispersing ability of CDs on the dispersion of CNTs was 2-HB-β-CD >> 6-HP-β-CD > β-CD > 6-HB-β-CD > 2-HP-β-CD. The movement in the FTIR spectra of the asymmetric and symmetric stretching vibrations of O-H of the composites means hydrogen bonding was an important factor on the dispersing ability. These results indicate that the type of interaction might be a combination of a weak interaction similar to a van der Waals type and hydrogen bonding mechanism. [ABSTRACT FROM AUTHOR]

This article studies the construction of a Bayesian confidence interval for risk difference in a 2×2 table with structural zero. The exact posterior distribution of the risk difference is derived under the Dirichlet prior distribution, and a tail-based interval is used to construct the Bayesian confidence interval. The frequentist performance of the tail-based interval is investigated and compared with the score-based interval by simulation. Our results show that the tail-based interval at Jeffreys prior performs as well as or better than the score-based confidence interval. [ABSTRACT FROM AUTHOR]