https://www.selleckchem.com/products/AG-490.html elevated stability in biomatrices, were found critical to method development and validation. The approach for the method development and validation provided a foundation for experiments that examine RK metabolism and bioavailability.Polymer-drug conjugates synthesized by binding therapeutic agents to functional polymers have long been a mainstay of prodrugs, while the slow drug release, insufficient efficacy of a single drug, and low selectivity hamper the clinical translation. By rational prodrug design, a targeted dual-acidity-labile polysaccharide-di-drugs conjugate was synthesized by one-pot simultaneous Schiff base and boronic esterification reactions between oxidized dextran (Dex-CHO) and cyclo-(Arg-Gly-Asp-D-Phe-Lys) (c(RGDfK)), doxorubicin (DOX), and bortezomib (BTZ). The polysaccharide-di-drugs conjugate (Dex-g-(DOX+BTZ)/cRGD) self-assembled into micelle with a diameter at around 80 nm and released the drugs simultaneously triggered by the acidic conditions. Dex-g-(DOX+BTZ)/cRGD specifically recognized and entered the cancer cells through the RGD-αvβ3 integrin interplay, selectively released DOX and BTZ in the acidic intracellular microenvironment, and efficiently inhibited the cell proliferation in vitro. More importantly, Dex-DOX/BTZ/cRGD showed higher intratumoral accumulation and better antitumor efficacy in vivo compared with free drugs and non-targeted control prodrug Dex-g-(DOX+BTZ). The findings indicated that this study provided a facile strategy to develop smart polymer-multi-drugs conjugates for targeted cancer chemotherapy.Background The urinary excreted selenium species selenosugar 1 (SeSug1) plays a key role for monitoring of supplemental selenium exposure, e.g. by occupational exposure. In order to reproduce its contents in the long term, the integrity of SeSug1 in the urine is essential. Studies on the stability of SeSug1 in urine samples stored at -20 °C have shown that degradation of SeSug 1