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High transparency Ce3+-doped dense gadolinium aluminum borosilicate (GS x) glass scintillator was synthesized in reducing atmosphere by melt-quenching process. The transmittance of the glasses exceeds 80%, and the light attenuation length is between 5-20 cm within the range of 400–600 nm. GS x glass shows an photoluminescence (PL) in range of 350–550 nm, with the strongest emission peak around 420 nm. The PL decay time of GS x glasses is around 37 ns, with a maximum PL quantum yield of 44.05%. The integrated X-ray excited luminescence (XEL) intensity of GS S glass is 52.5% compared with BGO crystal. For X-ray imaging, GS L glass based imaging system shows a high spatial resolution of 9 lp/mm, which is comparable to CsI:Tl X-ray detectors. Under γ-ray, the highest light yield of GS S glass is 1235 ph/MeV with an energy resolution of 24.0% at 662 keV, close to that of BSO crystal. The scintillation decay time of GS x glasses is consisted of fast (∼100 ns) and slow (∼560 ns) components. In thermally stimulated luminescence (TSL), GS S glass exhibits a strong TSL peak at approximately 440 K, with low intensity shoulders at about 520 K, implying different types of defects and traps. Therefore, GS x glass has promising prospects for X-ray imaging and high-energy physics applications. [ABSTRACT FROM AUTHOR]

Nanoparticles-based drug delivery systems show great promise for cancer therapy due to the advantages of crossing physiological barrier, high drug availability and good stability. However, deep tumor penetration, long blood circulation, and rapid drug release remain intractable problems for nanocarriers. In this work, we report a tumor microenvironment-sensitive nanodrug delivery system containing both acidic pH and hypoxia response sites to achieve enhanced drug permeability and on-demand release for precise cancer therapy. The covalent organic frameworks (COFs) with introduced azobenzene (azo) groups were used as employed as nanocarrier, and modified by pH-sensitive sulfamide-based zwitterionic polymers (PBA), followed by loading with the chemotherapeutic drug doxorubicin (DOX) to obtain COF-PBA@DOX. Copolymer PBA achieved charge conversions in tumor acidic environment, resulting in a positive charge on the nanocarrier surfaces, thus facilitating the augmented tumor accumulation. Meanwhile, azo which was formed the COF carrier, could be reduced to amines by the highly expressed azoreductase under tumor hypoxia conditions, resulting in nanoparticle dissociation and the drug-controlled release at the solid tumor sites. The fabricated dual-responsive nanomedicine, based on the surface charge-reversal of zwitterion in the acidic environment of tumor, can realize the accumulation and targeted drug release at the tumor site, which has great potential as a nanocarrier in tumor therapy. [Display omitted] [ABSTRACT FROM AUTHOR]