排序方式: 共有4条查询结果,搜索用时 0 毫秒
1
1.
Pawinee Theamdee Rakchart Traiphol Boonjira Rutnakornpituk Uthai Wichai Metha Rutnakornpituk 《Journal of nanoparticle research》2011,13(10):4463-4477
We here report the synthesis of magnetite nanoparticle (MNP) grafted with poly (ethylene glycol) methyl ether methacrylate
(PEGMA)-azobenzene acrylate (ABA) statistical copolymer via atom transfer radical polymerization (ATRP) for drug entrapment
and photocontrolled release. MNP was synthesized via thermal decomposition of iron (III) acetylacetonate in benzyl alcohol
and surface functionalized to obtain ATRP initiating sites. Molar compositions of the copolymer on MNP surface were systematically
varied (100:0, 90:10, 70:30, and 50:50 of PEGMA:ABA, respectively) to obtain water dispersible particles with various amounts
of azobenzene. The presence of polymeric shell on MNP core was evidenced by transmission electron microscopy (TEM). Drug loading
and entrapment efficiencies as well as drug release behavior of the copolymer–MNP complexes were investigated. It was found
that when percent of ABA in the copolymers was increased, entrapment and loading efficiencies of prednisolone model drug were
enhanced. Releasing rate and percent of the released prednisolone of the complex exposed in UV light were slightly enhanced
as compared to the system without UV irradiation. This copolymer–MNP complex with photocontrollable drug release and magnetic
field-directed properties is warranted for further studies for potential uses as a novel drug delivery vehicle. 相似文献
2.
Thanika Promchai Pawinee Janhom Wisanu Maneerat Roonglawan Rattanajak Sumalee Kamchonwongpaisan Stephen G. Pyne 《Natural product research》2020,34(10):1394-1398
AbstractA new 2-arylbenzofuran, spathobenzofuran (1), together with ten known compounds including a 2-arylbenzofuran, three pterocarpans and six isoflavones were isolated from the acetone crude extract of the stems of Spatholobus parviflorus. All compounds were characterised by spectroscopic methods. Compound 4 was active (MIC 8?µg/mL) against Gram-negative Pseudomonas aeruginosa TISTR 781 while compound 2 had modest activity against Gram-positive Staphylococcus aureus TISTR 1466 with a MIC value of 16?µg/mL. All isolated compounds showed no cytotoxicity against Vero and KB cells. 相似文献
3.
Piyarat Nimmanpipug Vannajan Sanghiran Lee Sorapong Janhom Pradoong Suanput Dherawan Boonyawan Kohji Tashiro 《Macromolecular Symposia》2008,264(1):107-112
Bombyx mori silk treated by cold SF6 plasma was found to show higher hydrophobic property than the original silk. In order to clarify the chemical changes occurring in this treatment, the changes of functional groups of silk surface were investigated by attenuated total reflection (ATR) infrared spectroscopy, surface charge determination, and quantum mechanical calculation. Infrared spectra of original and plasma-treated silks do not show any change in the frequency regions of amide I, II, and III bands which locate at around 1627, 1513, and 1228 cm−1, respectively. Slight changes were detected for the peak intensities of the bands locating in the frequency region of 1000–1050 cm−1 after plasma treatment. This suggests the formation of CF groups in the Bombyx mori silk chain. The zeta potential experiment suggested that the electrostatic charges of the silk surface were not affected by the plasma treatment. In order to investigate the surface state of the plasma treated silk, the density functional calculation was performed for the model compounds with similar chemical structure as that of Bombyx mori silk. In this calculation, a fluorine radical was located at the various positions of the model compound, and the energetically most plausible structures were extracted to show the chemical reaction of CH + F− → CF + H−. 相似文献
4.
Pawinee Wichienukul 《Tetrahedron letters》2010,51(24):3208-10067
An efficient synthesis of the influenza neuraminidase inhibitor prodrug oseltamivir phosphate (Tamiflu) from cheap, commercially available d-ribose is described. The main features of this approach comprise a metal (Zn, In)-mediated domino reaction and ring-closing olefin metathesis (RCM) of the resultant functionalized dienes to produce the Tamiflu skeleton. The synthesis described in this Letter represents a new and efficient transformation of a shikimic acid derivative into a 1,2-diamino compound which involved oxidation of an alcohol followed by reductive amination, regioselective ring opening of an amino pentylidene ketal and stereospecific nucleophilic replacement of a triflate with an azide. 相似文献
1