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Multifactor‐responsive nanomaterials have been playing a vital role in drug delivery developments. Given the advantages of nanotechnology‐based systems, employing stimuli‐sensitive agents could offer a step forward to targeted drug delivery. Hence, we targeted to apply both thermal and redox‐sensitive agents, which are poly(N‐isopropylacrylamide) (PNIPAM) and disulfide, onto a classic platform polyamidoamine (PAMAM) dendrimer. In particular, PAMAM G3.5 was first grafted by an outermost layer composed of cystamine moieties and partially grafted with PNIPAM segments. This novel nanomaterial was successfully verified by FTIR, 1H NMR, and Raman spectroscopy. Besides, morphological and surface characteristics were observed by DLS, TEM, and zeta potential. Our novel drug delivery system displayed a spherical shape with a hydrodynamic size of 43.61 ± 6.04 nm at 37°C and 68.99 ± 4.69 nm at 15°C, which proved its thermoresponsiveness. In parallel, the response of the nanoparticles toward redox concentration variation was testified that demonstrated a controlled drug release highly depending on physiological stimuli. We have also conducted in vitro DOX release and cytocompatibility of this drug delivery system, which can premise a smart strategy for nanoengineering in targeted drug delivery for cancer therapy. [ABSTRACT FROM AUTHOR]

This paper provides the synthesis, characterization, and in vitro studies of a novel drug delivery system towards applied research in targeted chemotherapy. The cover image created by Cuong Hung Luu features spherical nanoparticles targeting cancer tissue and breaking up into small pieces when approaching to kill cancer cells. PAMAM dendrimer particles showed more effective encapsulation capacity thanks to the heat-sensitive poly(N-isopropyl acrylamide) outer coating and the ability to cleave when encountering a high concentration of reducing agents. [Extracted from the article]

We investigated the effect of tritium upload in the dense, polycrystalline MgB2 superconductor for 2 and 216 h. One basic property, the critical temperature Tc, slowly changes in time but is independent of the duration of tritium uptake. Immediately after tritiation, Tc shows a slight increase to 39.1 K but decreases to the critical temperature of the untritiated (pristine) sample, Tc = 38.8 K, after 370 days. The critical current density is strongly dependent on the tritium upload time, mainly at high magnetic fields. The underlying physics is discussed. This behaviour makes the use of MgB2 based conductors advantageous in tritium environments like fusion reactors. [ABSTRACT FROM AUTHOR]