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In recent years, copper-based halide scintillators have attracted tremendous attention due to their excellent luminescent properties and low manufacturing costs. Herein, a high-performance and low-cost Cs 5 Cu 3 Cl 6 I 2 scintillator is prepared by simple mechanical grinding. The mixed-halide Cs 5 Cu 3 Cl 6 I 2 phosphor exhibits a blue emission centered at 475 nm with a large stokes shift, originating from the self-trapped exciton emission of Cu sites. The photoluminescence quantum yield (PLQY) of Cs 5 Cu 3 Cl 6 I 2 can be increased to 88.4% from 20.4% by the efficient suppression of the anion vacancy defects. In addition, the Cs 5 Cu 3 Cl 6 I 2 scintillator shows a high steady-state X-ray to light conversion efficiency of about 57000 photons/MeV, good X-ray linear response, and low detection limit of 71.9 nGy air /s. The X-ray imaging results based on the Cs 5 Cu 3 Cl 6 I 2 scintillator screen display a high spatial resolution of 9.0 line-pairs per millimeter (lp/mm). Furthermore, Cs 5 Cu 3 Cl 6 I 2 exhibits good radiation stability under a total dose of 113.58 Gy air. Overall, the Cs 5 Cu 3 Cl 6 I 2 scintillator prepared by mechanical grinding method has the advantages of low cost, high efficiency, and good radiation resistance, suggesting its huge potential in X-ray detection and imaging. [ABSTRACT FROM AUTHOR]

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]

Liposomal delivery is a well-established approach to increase the therapeutic index of drugs, mainly in the field of cancer chemotherapy. Here, we report the preparation and characterization of a new liposomal formulation of a derivative of lomeguatrib, a potent O 6 -methylguanine-DNA methyltransferase (MGMT) inactivator. The drug had been tested in clinical trials to revert chemoresistance, but was associated with a low therapeutic index. A series of lomeguatrib conjugates with distinct alkyl chain lengths – i.e. C12, C14, C16, and C18 – was synthesized, and the MGMT depleting activity as well as cytotoxicity were determined on relevant mouse and human glioma cell lines. Drug-containing liposomes were prepared and characterized in terms of loading and in vitro release kinetics. The lipophilic lomeguatrib conjugates did not exert cytotoxic effects at 5 μM in the mouse glioma cell line and exhibited a similar MGMT depleting activity pattern as lomeguatrib. Overall, drug loading could be improved by up to 50-fold with the lipophilic conjugates, and the slowest leakage was achieved with the C18 derivative. The present data show the applicability of lipophilic lomeguatrib derivatization for incorporation into liposomes, and identify the C18 derivative as the lead compound for in vivo studies. [ABSTRACT FROM AUTHOR]