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An efficient Pd@MIL-101(Cr) catalyst prepared with MOCVD approach for 2-butyne-1,4-diol hydrogenation with excellent activity, stability and selectivity.

The present study aimed to investigate the effect of monomethoxy poly(ethylene glycol)-block-poly(D,L-lactic acid) (mPEG-PLA) on the activity of P-glycoprotein (P-gp) in Caco-2 cells and further unravel the relationship between PLA chain length in mPEG-PLA and influence on P-gp efflux and the action mechanism. The transport results of rhodamine 123 (R123) across Caco-2 cell monolayers suggested that mPEG-PLA unimers were responsible for its P-gp inhibitory effect. Furthermore, transport studies of R123 revealed that the inhibitory potential of P-gp efflux by mPEG-PLA analogues was strongly correlated with their structural features and showed that the hydrophilic mPEG-PLA copolymers with an intermediate PLA chain length and 10.20 of hydrophilic-lipophilic balance were more effective at inhibiting P-gp efflux in Caco-2 cells. The fluorescence polarization measurement results ruled out the plasma membrane fluidization as a contributor for inhibition of P-gp by mPEG-PLA. Concurrently, mPEG-PLA inhibited neither basal P-gp ATPase (ATP is adenosine triphosphate) activity nor substrate stimulated P-gp ATPase activity, suggesting that mPEG-PLA seemed not to be a substrate of P-gp and a competitive inhibitor. No evident alteration in P-gp surface level was detected by flow cytometry upon exposure of the cells to mPEG-PLA. The depletion of intracellular ATP, which was likely to be a result of partial inhibition of cellular metabolism, was directly correlated with inhibitory potential for P-gp mediated efflux by mPEG-PLA analogues. Hence, intracellular ATP-depletion appeared to be possible explanation to the inhibition mechanism of P-gp by mPEG-PLA. Taken together, the establishment of a relationship between PLA chain length and impact on P-gp efflux activity and interpretation of action mechanism of mPEG-PLA on P-gp are of fundamental importance and will facilitate future development of mPEG-PLA in the drug delivery area.

AuÀPd alloy catalysts were successfully loaded into aminefunctionalized metal-organic framework (MOF, UiO-66-NH 2 ) via direct absorption/reduction method. The existence of Pd in the alloy was revealed by using in situ fourier transform infrared spectroscopy (FTIR) with CO as probe molecules. The X-ray diffraction (XRD) and transmission electron microscopy (TEM) results demonstrated the AuÀPd alloys were well dispersed within the robust UiO-66-NH 2 . AuÀPd alloy nanoparticles with low Pd content were well dispersed within UiO-66-NH 2 and exhibited high stability and selectivity for N-benzylaniline (98%) in the direct reductive amination with benzaldehyde and nitrobenzene.