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-poly(NIPAM-
-HEMA) graft copolymersQuynh, T. M.*; Yoneyama, Masaru*; Maki, Yasuyuki*; Nagasawa, Naotsugu; Dobashi, Toshiaki*
Key Engineering Materials, 459, p.51 - 56, 2010/12
Times Cited Count：3 Percentile：81.92(Engineering, Electrical & Electronic)Different poly(
-isopropylacrylamide-
-hydroxyethyl methacrylate) copolymers [P(NIPAM--HEMA)] were synthesized from -isopropylacrylamide (NIPA) and hydroxyethyl methacrylate (HEMA) monomers by both radical and radiation polymerizations for comparison. PLLA-
-P(NIPAM--HEMA) graft copolymers were synthesized from L-lactide and respective P(NIPAM--HEMA) copolymers by ring opening polymerization. Both NMR and FTIR analyses demonstrated the PLLA chains have been grafted on to the P(NIPAM--HEMA) backbone. These graft copolymers revealed the cloud point temperature higher than that of PNIPAM homopolymer as determined by optical transmittance. The graft copolymers self-assembled into micelles with regularly spherical structures as observed by atomic force microscopy (AFM). The properties of these graft copolymers are interesting for the drug delivery system.
-ray irradiationFurusawa, Kazuya*; Kita, Erika*; Saeki, Toshihiko*; Nagasawa, Naotsugu; Nishi, Norio*; Dobashi, Toshiaki*
Journal of Biomaterials Science; Polymer Edition, 19(9), p.1159 - 1170, 2008/09
To insolubilize DNA for preparing a novel carcinogen adsorbent, effects of -ray irradiation on aqueous solutions of mixtures of DNA with cross-linking biopolymers (CBP): gelatin, bovine serum albumin, carboxymethyl cellulose and hydroxyethyl-cellulose, O-[2-hydroxy-3-(trimethyl ammonio)-propyl], chloride have been studied. DNA-CBP hybrid gels were successfully prepared from aqueous mixtures of DNA with CBP in a limited range of irradiation dose. Gel fraction (Gf) and swelling ratio (S) of the hybrid gels were measured. The Gf and S of hybrid gels increased and decreased, respectively, with increasing irradiated dose. Adsorption of one of carcinogen, acridine orange, was also examined for the gels. From the experimental results, the optimum condition for preparing insolubilized homogeneous DNA gels was determined.
-ray irradiationFurusawa, Kazuya*; Kita, Erika*; Dobashi, Toshiaki*; Nagasawa, Naotsugu; Tamada, Masao
JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 54, 2007/02
DNA-derived environmental cleanup material was prepared by -ray irradiation on DNA and cross-linking polymer mixtures. The -ray cross-linking biopolymer used for the study was carboxymethylcellulose (CMC), gelatin, bovine serum albumin (BSA), carboxymethylchitosan, and catinal. The DNA and cross-linking biopolymer mixtures were gelled homogenously by -ray irradiation except for DNA + CM-chitosan mixture under the experimental condition. Grams of acrydine orange absorbed in dried gels decreased with increasing irradiated dose. The optimum condition for obtaining the maximum absorbed efficiency of the gel was determined.
Morishita, Satoshi*; Umino, Yuya*; Kita, Rio*; Shinyashiki, Naoki*; Yagihara, Shin*; Furusawa, Kazuya*; Dobashi, Toshiaki*; Nagasawa, Naotsugu
Tokai Daigaku Kiyo Rigakubu, 41, p.105 - 112, 2006/03
Dielectric relaxation measurements were performed for the systems of hydroxypropylmethylcellulose (HPMC) in 1,4-dioxane and HPMC gel immersed in 1,4-dioxane. The HPMC gel was prepared by an electron beam irradiation for HPMC aqueous solution. Two relaxation processes were observed for both samples. Higher frequency process of each sample in the range of 300 kHz - 100 MHz was attributed to a chain motion of HPMC, while lower frequency process observed for the HPMC gel in the range 100 Hz - 300 kHz was significantly larger than the HPMC in dioxane. This observation indicates that DC conductivity due to the beam irradiation had a pronounced effect for the slower relaxation process.
Furusawa, Kazuya*; Kita, Erika*; Nagasawa, Naotsugu; Dobashi, Toshiaki*; Tamada, Masao
no journal, ,
no abstracts in English
-irradiation on mixtures of DNA and bovine serum albuminSaito, Hiroyuki*; Furusawa, Kazuya*; Dobashi, Toshiaki*; Nagasawa, Naotsugu
no journal, ,
Halogenated aromatic compounds, such as dioxin and polychlorinated biphenyl, result in cancer and reproductive anomaly through intercalation into the major grooves and interstices between base pairs of double helical DNA. Water-insoluble DNA-based materials can be utilized as the most efficient adsorbents of such toxic agents. In this study, we have successfully prepared DNA-bovine serum albumin (BSA) hybrid gels from aqueous mixtures of DNA with BSA by -ray irradiation. We have characterized the gel property and adsorption property of DNA-BSA hybrid gels. The interesting result that mixing -ray-scission polymers of DNA and BSA changes them to be -ray-crosslinking materials is discussed.
-ray irradiationFurusawa, Kazuya*; Kita, Erika*; Saheki, Toshihiko*; Nagasawa, Naotsugu; Nishi, Norio*; Dobashi, Toshiaki*
no journal, ,
To insolubilize DNA for preparing a novel carcinogen adsorbent, effects of -ray irradiation on aqueous solutions of mixtures of DNA with radiation-induced crosslinking-type biopolymers (RCBP) such as Type A gelatin, bovine serum albumin (BSA), carboxymethyl cellulose (CMC) and Catinal (hydroxyethyl-cellulose, O-[2-hydroxy-3- (trimethyl ammonio)-propyl], chloride) have been studied. DNA-RCBP hybrid gels were successfully prepared from aqueous mixtures of DNA with RCBP in a limited range of irradiation dose. Gel fraction (Gf) and swelling ratio (S) of the hybrid gels were measured. The Gf and S of hybrid gels increased and decreased, respectively, with increasing irradiated dose. Adsorption of one of carcinogen, acridine orange, was also examined for the gels. From the experimental results, the optimum condition for preparing insolubilized homogeneous DNA gels was determined.
-irradiationSaito, Hiroyuki*; Furusawa, Kazuya*; Nagasawa, Naotsugu; Tamada, Masao; Dobashi, Toshiaki*
no journal, ,
no abstracts in English
rays irradiation and its charactarizationSaito, Hiroyuki; Furusawa, Kazuya*; Nagasawa, Naotsugu; Tamada, Masao; Dobashi, Toshiaki*
no journal, ,
no abstracts in English
-rays irradiationSaito, Hiroyuki*; Dobashi, Toshiaki*; Furusawa, Kazuya*; Nagasawa, Naotsugu; Tamada, Masao
no journal, ,
no abstracts in English
Narasaki, Yoko*; Dobashi, Toshiaki*; Sawada, Shinichi; Enomoto, Kazuyuki; Hasegawa, Shin; Maekawa, Yasunari
no journal, ,
The novel polymer electrolyte membranes (PEMs) showing the proton conductivity only in the thickness direction were prepared based on poly (ether ether ketone) (PEEK), which has good mechanical strength and gas barrier property at high temperature, by using heavy-ion beam irradiation technique. The preparation procedure was as follows: (1) thermal polymerization of divinylbenzene into PEEK film; (2) irradiation of Xe ions at 3
10
ions/cm
to the PEEK film; (3) graft polymerization of ethyl styrenesulfonate (ETSS) into ion latent track regions; and (4) introduction of sulfonic acid groups by hydrolysis. The resultant PEM with the ETSS grafting degree of 23% exhibited the thickness-direction conductivity of 0.0093 S/cm, which was three-times higher than the in-plane conductivity (0.0033 S/cm). This result suggests that the sulfonic acid groups were introduced only in the ion latent track regions, thereby allowing the PEM to have anisotropic conduction property.
-rays irradiation on concentrated aqueous solutions of BSA, DNA and their mixtureOkamura, Hideki*; Nagasawa, Naotsugu; Furusawa, Kazuya*; Taguchi, Mitsumasa; Dobashi, Toshiaki*
no journal, ,
no abstracts in English
