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排序方式: 共有1915条查询结果,搜索用时 16 毫秒
101.
Carla Marisa Brito Carvalho Marta Akemi FujitaTimothy John Brocksom Kleber Thiago de Oliveira 《Tetrahedron》2013
New β-fused uracil-porphyrin conjugates were synthesized by the tetramerization of uracil-pyrroles under acidic conditions. Two different synthetic approaches were systematically studied in order to evaluate their efficiency, as well as the possibility to obtain a single regioisomer. Metallation effects were studied for aggregation in solution, and preliminary photophysical experiments were also performed in order to evaluate the potential of these new compounds. 相似文献
102.
Dr. Anthony J. Kim Dr. Nicholas J. Boylan Dr. Jung Soo Suk Minyoung Hwangbo Tao Yu Benjamin S. Schuster Dr. Liudimila Cebotaru Dr. Wojciech G. Lesniak Joon Seok Oh Pichet Adstamongkonkul Ashley Y. Choi Prof. Dr. Rangaramanujam M. Kannan Prof. Dr. Justin Hanes 《Angewandte Chemie (International ed. in English)》2013,52(14):3985-3988
103.
FTIR photothermal beam deflection spectroscopy (PBDS) was used to record infrared spectra of medium-temperature carbons before and after they had been subjected to treatments with aqueous HNO3 or H2O2 solution. Changes in the functional groups present on the carbon surfaces can be clearly observed. 相似文献
104.
Amine containing cationic methacrylate copolymers as efficient gene delivery vehicles to retinal epithelial cells 下载免费PDF全文
Jon Zarate Gustavo Puras David Mecerreyes Haritz Sardon J. L. Pedraz 《Journal of polymer science. Part A, Polymer chemistry》2017,55(2):280-287
Non‐viral gene delivery vectors have emerged as potential alternatives in the field of gene therapy by replacing the biological viral vectors. DNA–cationic polymer complexes are one of the most promising systems to target many inborn or acquired diseases without the utilization of conventional drugs. Despite the excellent binding efficiency of cationic polymers, the gene transfection seems limited to date. In this work, a series of ammonium‐based block‐copolymers with different alkyl side chains (ethyl, butyl, and hexyl) and functionality (alcohol, amine, and alkyl) have been prepared to evaluate their capacity to deliver genetic material. First, different ionic liquid monomers with different pendent functional groups were prepared and characterized. Then, polyplexes elaborated with different polymers at several polymer DNA ratios (w/w) were characterized in terms of size, zeta potential, and DNA binding, release, and protection capacity. Finally, the transfection efficiency and cell viability was evaluated in ARPE19 cells. We found that only the systems containing the amine pendent group were able to transfect ARPE19 cell and, that this amine containing polymer was less cytotoxic even at high polymer/DNA ratios (30:1). In conclusion, our studies suggested that the proper selection of the pendent group substantially impacts overall transfection efficiency of cationic polymers. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 280–287 相似文献
105.
RAFT synthesis of an amphiphilic block copolymer bearing chlorin rings in the hydrophobic segment and its application in photodynamic therapy 下载免费PDF全文
Makoto Obata Shuto Tanaka Hiroshi Mizukoshi Eika Ishihara Masaki Takahashi Shiho Hirohara 《Journal of polymer science. Part A, Polymer chemistry》2017,55(20):3395-3403
RAFT polymerization of styrene (St) in the presence of 5,10,15,20‐tetrakis(pentafluorophenyl)porphyrin (TFPP) was conducted using 4‐cyano‐4‐(thiobenzoyl)thiopentanoic acid as a chain‐transfer agent and azobisisobutyronitrile as an initiator at 60 °C. The resulting polymer exhibited a chlorin‐like UV‐vis spectrum, which indicated that the polymer possessed a reduced TFPP structure. Furthermore, an SEC trace recorded using UV‐vis detector (λ = 410 nm), which selectively detected the TFPP‐incorporated polymer, shifted toward higher molecular mass as the polymerization progressed. This evidence indicated that TFPP acted as a vinylene‐type monomer, such as maleimide, to form a copolymer, namely, poly(St‐co‐TFPP). The mole fraction of TFPP units was estimated to be 0.74 × 10?3, which was close to that in the feed (1 × 10?3). Chain extension of poly(St‐co‐TFPP) with polyethylene glycol monomethyl ether acrylate (PEGA) was performed to afford the amphiphilic block copolymer poly(St‐co‐TFPP)‐b‐poly(PEGA). The degrees of polymerization of St and PEGA were determined to be 64 and 75, respectively. Poly(St‐co‐TFPP)‐b‐poly(PEGA) formed micelles following dialysis. The median diameter of the micelles in solution was determined to be 16 nm by DLS. The photocytotoxicity of the micelle solution was evaluated in a human glioblastoma cell line (U251) and an N‐methyl‐N'‐nitro‐N‐nitrosoguanidine‐induced mutant of a rat murine RGM‐1 gastric carcinoma mucosal cell line (RGK‐1). © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 3395–3403 相似文献
106.
FTIR photothermal beam deflection (PBD) spectroscopy was used to record PBD spectra of IR-absorbing gases in presence of IR-absorbing and non-absorbing solids. The presence of the solid, IR-absorbing or not, causes asymmetry at the juncture of the IR and probe laser 相似文献
107.
108.
《中国化学》2017,35(9):1445-1451
Graphene oxide (GO ) and its functionalized derivatives have attracted increasing attention in medical treatment. Herein, a reduction sensitive PEI‐GO ‐SS ‐TPP was synthesized for photodynamic therapy. More than 80% porphyrin release was observed in the presence of 10 mmol•L−1 DTT in one day. The confocal laser scanning microscopy confirmed that the cell uptake efficiency of PEI‐GO‐SS‐TPP was remarkably enhanced as compared to free porphyrin which was significantly dependent on incubation time. For photodynamic therapy, GSH‐OEt could effectively increase the photodynamic therapy efficiency of PEI‐GO ‐SS ‐TPP . Compared with free porphyrin, the toxicity from PEI‐GO ‐SS ‐TPP is much higher with a low IC50 (2.1 µg/mL ) value. All results indicate that the PEI‐GO ‐SS ‐TPP PSs are promising for photodynamic therapy. 相似文献
109.
110.