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Abstract: In this study, we investigated the PEG attachment site of mono-PEGylated Endostar, a modified recombinant human endostatin approved in China for lung cancer. N-terminal site-directed mono-PEGylation of Endostar was accomplished using mPEG-propionaldehyde derivatives (Mw=20kDa) under slightly acidic pH conditions (pH 5.5). One-step cation exchange chromatography was used to purify the mono-PEGylated Endostar. Following tryptic digestion, the peptide fragment containing PEG was separated by SDS-PAGE. Barium iodide staining and Western blotting were used to detect the PEG moiety and the N-terminus of Endostar, respectively. The peptide fragment stained by barium iodide showed a positive response to anti-(His) 6 mAb, demonstrating that PEG was located at the N-terminus of Endostar. LC/MS was applied to verify the occurrence of mono-PEGylation at the N-terminus of Endostar. [Copyright &y& Elsevier]

Ancient Chinese objects from the eighth to the third centuries BC were studied by Raman microscopy and scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDX). They included blue glassy faience beads, blue or purple beads of vitreous sinter material high in lead and barium, earrings and octagonal sticks. Man-made Han blue (BaCuSi4O10) and Han purple (BaCuSi2O6) were identified by Raman microscopy, as was ultramarine blue in two faience beads. SEM-EDX studies on the compact bodies of one bead and one octagonal stick revealed vitreous and crystalline phases, the latter with the approximate composition (BaO)n·(CuO)m ·2SiO2 2, n, m = 1 or 2. All objects were found to contain varying amounts of lead. [ABSTRACT FROM AUTHOR]

Barium copper silicate, BaCuSi4O10, an artificially produced mineral, has been identified on Chinese painted ceramic objects attributed to the Han dynasty (208 BC-220 AD). The mineral has also been observed as an important component in octagonal sticks probably dating to the Warring States period (475-221 BC) or to the Han dynasty. This man-made mineral has been hitherto unreported as a pigment in the ancient Chinese palette. [ABSTRACT FROM AUTHOR]