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Thin films of incompatible polymer blends can form a variety of structures during preparation and subsequent annealing process. For the polymer blend system consisting of polystyrene and poly(styrene-co-p-bromo-styrene), i.e., PS/PBrxS, its compatibility could be adjusted by varying the degree of bromination and the molecular weight of both components comprised. In this paper, surface chemical compositions of the cast and the annealing films were investigated by X-ray photoelectron spectroscopy (XPS) and contact angle measurement; meanwhile, surface topographical changes are followed by atomic force microscopy (AFM). In addition, substantial attention was paid to the effect of annealing on the morphologic variations induced by phase separation and/or dewetting of the thin film. Moreover, the influences of the molecular weight, Mw, as well as the brominated degree, x%, on the sample surface are explored systematically, and the corresponding observations are explained in virtue of the Flory-Huggins theory, along with the dewetting of the polymer thin film. [ABSTRACT FROM AUTHOR]

Objective: To prepare the new traditional Chinese medicine preparation--pH-dependent brevisapin colon-specific tablets, and investigate its in vitro release, in order to discuss the feasibility of preparing colon-targeted traditional Chinese medicines., Method: With scutellarin, the active ingredient in brevisapin, as the evaluation index, coating prescriptions of the preparation was screened. The in vitro release determination method was adopted to detect the in vitro release performance of the preparation., Result: The in vitro release determination results showed no brevisapin in artificial pH 1. 2 dilute hydrochloric acid solution for 2 h, an accumulated dissolution rate of less than 5% in pH 6. 8 phosphate buffer solution for 4 h, but an accumulated dissolution rate exceeding 90% in pH 7. 6 phosphate buffer solution for 1 h., Conclusion: Brevisapin colon-specific tablets prepared can realize colon-specific release.

Objective: To establish an HPLC method for the determination of ephedrine hydrochloride, D-pseudo-ephedrine and amygdalin in Xiao'er Pingchuan Qutan granule., Method: Pheny ether chromatographic column (4.6 mm x 250 mm, 5 microm) was adopted, with acetonitrile-0.1% phosphoric acid (containing 0.1% three ethylamine) (3:97) as the mobile phase. The UV detection wavelength was at 210 nm, with the flow rate of 1 mL x min(-1), and column temperature was at 35 degrees C., Result: The linearity of ephedrine hydrochloride, D-pseudo-ephedrine and amygdalin ranged between 0.078 60-3.144 microg (r = 1.000 0), 0.103 4-2.068 microg (r = 0.999 7) and 0.430 5-3.157 microg (r = 0.999 8), respectively. Their average recoveries were 98.46% (RSD 1.1%), 103.0% (RSD 1.5%) and 97.15% (RSD 2.1%), respectively., Conclusion: The method is simple, stable and reliable that it can be used to determine the content of ephedrine hydrochloride, D-pseudo-ephedrine and amygdalin in Xiao'er Pingchuan Qutan granule.