The described work demonstrates proof-of-principle using membrane sample preparation techniques to form DPS samples from whole blood for subsequent bioanalysis by LC/MS/MS. This approach has the potential to eliminate the hematocrit issues from the current controversy surrounding validation of DBS assays.

No abstract

An aryne 1,2,3-trisubstitution with aryl allyl sulfoxides is accomplished, featuring an incorporation of C-S, C-O, and C-C bonds on the consecutive positions of a benzene ring. The reaction condition is mild with broad substrate scope. Preliminary mechanistic study suggests a cascade formal [2 + 2] reaction of aryne with S═O bond, an allyl S → O migration, and a Claisen rearrangement.

Alkali lignin (AL), an anionic polymer, is a byproduct of the paper industry. AL was first modified by quaternization to synthesize quaternized alkali lignin (QAL). The aim of the present study is to reveal the effects of sodium dodecyl benzenesulfonate (SDBS) on the microstructure of QAL. The interaction between SDBS and QAL is studied by means of zeta potential, fluorescence spectrophotometer, and static contact angle measurement. The results indicated that there is an electrostatic interaction and a hydrophobic interaction between QAL and SDBS. The SDBS/QAL complex can self-assemble into lignin-based colloidal spheres (LCSs) in an ethanol/water mixture, which have remarkable avermectin (AVM) encapsulation efficiency and antiphotolysis performance. The cumulative release amount of AVM encapsulated by LCS (LCS@AVM) after 72 h was 77%, and the release was still going on. The release behaviors of LCS@AVM can be controlled by adjusting the ratio (w/w) of LCS to AVM. More than 85% of AVM could be preserved even after 96 h of UV irradiation. LCS showed controlled release and UV-blocking performance for AVM.

A water-soluble polysaccharide (POP1) was isolated from Portulaca oleracea L. Four sulfated derivatives of POP1 (POP1-s1, POP1-s2, POP1-s3 and POP1-s4) were prepared by chlorosulfonic acid method with N,N-Dicyclohexylcarbodiimide (DCC) as a dehydration-condensation agent. FT-IR spectra and 13C NMR spectra indicated the sulfated groups had been introduced at the C-6 and C-2 positions of POP1. Sulfated derivatives had different degree of substitution (DS) ranging from 1.01 to 1.81, and different weight-average molecular mass (Mw) ranging from 41.4 to 48.5 KDa. Sulfated derivatives except POP1-s5 inhibited the growth of HepG2 cells and Hela cells in vitro significantly, which indicated that sulfated modification could enhance cytotoxicity of POP1 on tumor cells. Flow cytometric studies revealed that sulfated derivatives could mediate the cell-cycle arrest of Hela cells in the S phase.