Materials Science & Engineering C-Materials for Biological Applications
·
2016
·
IF 3.42
Kai Chen,Jiacheng Li,Yuhong Feng,Furui He,Qingfeng Zhou,Dunchao Xiao,Yiyuan Tang
Amphiphilic polymers that form self-assembled structures in aqueous media have been investigated and used for the diagnosis and therapy of various diseases, including cancer. In our work, a series of environment-sensitive hydrophobic alginates (Ugi-Alg) with various weight-average molecular mass values (Mw ~ 6.7 × 10 5 –6.7 × 10 4 g/mol) were synthesized via Ugi reaction. The structure of Ugi-Alg was characterized by 1 HNMR spectrometer. The electrostatic self-assembly of different molecular weight (Mw) and composition (M/G ratio) of Ugi-Alg chain under various Na + concentrations, was investigated by dynamic light scattering, electron spin resonance experiments, and transmission electron microscopy. Result showed that by comparing to other Ugi-Alg, the mid-Mw Ugi-Alg (Mw ~ 2.8 × 10 5 g/mol) could form stable and homogeneous nanoparticles in low Na + concentration solution. However, G/M values exerted no obvious effect on nanoparticles structure. Additionally, steady-shear flow, thixotropy and dynamical viscoelasticity tests were performed to characterize the rheological behavior of Ugi-Alg aqueous solutions as influenced by Mw and M/G ratio. All of the samples exhibited a non-Newtonian shear-thinning behavior above a critical shear rate ( γ ̇ c 2 ). The greater the Mw, the more sensitive the temperature-dependent behavior will be. The upward-downward rheograms showed that all of the systems evaluated in this study displayed a hysteresis loop, indicating a strong thixotropic behavior, and the thixotropic of mid-Mw Ugi-Alg was the strongest. The dynamical viscoelastic properties were characterized by oscillatory frequency sweep, revealing the gel-like viscoelastic behavior of mid-low Ugi-Alg and the fluid-like viscoelastic behavior of high-Mw Ugi-Alg.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION
·
2016
·
IF 1.733
Kangqi Sun,Juhua Guo,Yufeng He,Pengfei Song,Yubing Xiong,Rong-Min Wang
Using feather keratin (FK) as a biocompatible and inexpensive biopolymer, a kind of dual-sensitive keratin-based polymer hydrogel (FK/PNiPA/PIAc-Gel) with interpenetrating network structure was prepared by two-step polymerization of N-isopropyl acrylamide (NiPA) and itaconic acid (IAc) in presence of crosslinker. After being characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis and scanning electron microscopy, its swelling behaviors and environmental sensitivity were investigated. The obtained biopolymer based hydrogel has good swelling and deswelling performance, and it is sensitive to pH value, temperature and salts of environment. Using anticancer drug, doxorubicin hydrochloride (Dox·HCl), and Bovine serum albumin (BSA) as different drug molecules, its release behaviors in different environment were investigated. It was found that the release behaviors of FK/PNiPA/PIAc-Gel were controllable via adjusting pH value or temperature of environment. The cumulative release of the anticancer drug (Dox·HCl) reached 93.3% within 16 h, and the cumulative release rate of macromolecular drug (BSA) got to 75.9% in 24 h. In summary, the keratin-based biopolymer hydrogel with interpenetrating network structure, pH-sensitivity and temperature sensitivity are potentially applied to sustain drug carrier and humid medicinal material in the biomedical field or clinical nursing field.
研究领域:
生物材料学
·
药剂学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
OPTICAL MATERIALS
·
2025
·
IF 4.2
Daiwen Xiao,Ka-Leung Wong,Peter A. Tanner
The behavior of nanoparticles in media of different refractive index has received considerable theoretical and experimental investigation. However, the behavior of larger particles, of micron size, has not been established. We have chosen Eu 3+ as a marker of environmental changes. Dilution of this ion into LaPO 4 gives a simple, fingerprint emission spectrum which has been studied via its luminescent lifetime, the R 2 (( 5 D 0 → 7 F 2 )/( 5 D 0 → 7 F 1 ) intensity ratio) and the electric dipole:magnetic dipole intensity ratio, (ED:MD), of spectral features. Measurements of micron-sized particles of LaPO 4 :Eu 3+ synthesized by several methods have been made for dispersions in alcohols, in compressed glass discs, in melted glass discs, in phosphor in glass (PiG) and in melted PiG. The experimental results are discussed and rationalized. The Eu 3+ 5 D 0 emission lifetime is reasonably constant in the bulk powders, powders dispersed in alcohols or compressed discs but is smaller in PiGs and melted glass discs. In the PiGs the structural integrity of LaPO 4 :Eu 3+ is maintained until they are melted at higher temperature. The change in lifetime, when varying the composition of the PiG, follows the Virtual Cavity Model. For dispersal of the particles in solvents there is a cut-off particle size below 1 μm where the electronic spectra of the moiety become insensitive to the environment and the properties are determined by refractive index. The remarkable change in R 2 ratio in the different systems considered – by a factor of nearly 600 % - and the corresponding decrease in 5 D 0 lifetime – by a factor of nearly 60 % - illustrates the versatility of the lanthanide ion.
研究领域:
材料科学
·
发光材料
·
无机化学
·
光子学
·
固态物理
✓ 已验证
产品关联
DOI
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
·
2020
·Vol. 34
·期 8
·e5703
·
IF 3.14
Xue-Wen Liu,Ning-Yi Liu,Yuan-Qing Deng,Shan Wang,Ting Liu,Yu-Cai Tang,Yuan-Dao Chen,Ji-Lin Lu
The detection of G-quadruplex is of major interest. Nitro-substituted ruthenium (II) complexes have attracted much attention due to fluorescent sensitivity to environment change. We report here a new nitro-substituted ruthenium (II) complex, [Ru (phen) 2 (hnoip)] 2+ ( 1) (hnoip = 2-(2-hydroxyl-5-nitrophenyl)imidazo[4,5- f ][1,10-phenanthroline]), which displays distinct fluorescent properties in aqueous solution and non-aqueous solvents. This complex exhibits large fluorescence enhancement after binding with G-quadruplex DNA, and displays good fluorescent selectivity over other DNAs. The limit of detection is 6 n m for 22AG in Na + and 43 n m for 22AG in K + , respectively. The results demonstrated that nitro-substituted ruthenium (II) complexes can be utilized to design as G-quadruplex fluorescent probes by protection of the nitro group on the complex from water.
研究领域:
化学
·
生物化学
·
分子生物学
✓ 已验证
DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2021
·Vol. 222
·期 13
·2100070
·
IF 2.527
Hongyang Wang,Shuai Lan,Yu Zhang,Lu Zhang,Dandan Jia,Weiguo Zhang,Chun Liu,Lei Cao,Dongjun Wang
For the unusual phenomenon of nontraditional intrinsic luminescence, a systematic fluorescence study is conducted in the phase transformation from solution through hydrogel to solid states. In this process, significant differences are found in fluorescence intensity, peak position, lifetime, and excitation-dependent emission. In particular, the samples in the hydrogel state show two fluorescent peaks at 480 and 516 nm, respectively, while only one fluorescent peak is detected in the cases of solution (at 516 nm) or solid (at around 450 nm). More interestingly, the longer wavelength peak presents excitation-dependent fluorescence, and the shorter one is excitation-independent. These unique fluorescent observations can be ascribed to the fact that the aggregates of amine groups act as the actual fluorescent centers, which are quite sensitive to their surrounding microenvironments. Based on these results, some simulation tests of sensors and intelligent hydrogels in response to water are also studied.
研究领域:
材料科学
·
光学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2021
·
IF 7.46
Mingyu Pi,Daofu Wu,Jian Wang,Kai Chen,Jiao He,Jie Yang,Dingke Zhang,Shijian Chen,Xiaosheng Tang
Benefiting from the environmental sensitivity, perovskite materials show great potentials in sensor devices. Especially, humidity sensors are regarded as reversing disadvantage to advantage of the metal halide perovskites. However, the low stability and the toxicity of lead are the major impediment to practical applications for humidity sensors. Herein, in this work, we prepared Cs 2 SnCl 6 perovskites by a solution-phase synthesis method and demonstrated the excellent humidity sensing property of lead-free perovskite Cs 2 SnCl 6 -based sensors. The fabricated humidity sensors exhibit an ultrahigh impedance change of 2.2E6 from relative humidity (RH) of 11–95% and a short response time (0.8 s) and recovery time (5.4 s), which possesses great potentials in real-time moisture detection. Furthermore, it also presents a good capability of reversibility and an impressive stability. The underlying humidity sensing mechanism under different humidity conditions is also discussed in detail. Our results provide a simple, economic and environmental-friendly method for preparing superior-performance and real time humidity sensor.
研究领域:
材料科学
·
传感器技术
·
环境监测
·
纳米技术
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2020
·Vol. 56
·期 6
·4380-4395
·
IF 3.553
Li Lin,Zhang Peng,Yang Xiucheng,Li Congcong,Guo Yan,Sun Kaoxiang
Abstract A receptor-mediated, active-targeting and glutathione (GSH) turn-on charge-reversal core/shell nanocomplex HA-MEA-s-s-TGA/PAMAM@DOX was constructed to achieve increased stability, improved cellular uptake, facilitated endo-lysosomal escape and enhanced antitumor efficacy. This nanocomplex was composed of anionic hyaluronic acid (HA)-graft GSH-sensitive HA-MEA-s-s-TGA as the outer shell and the cationic PAMAM@DOX core with encapsulated doxorubicin (DOX) into the hydrophobic cavities of polyamidoamine (PAMAM) dendrimers. We hypothesized that the anionic outer layer could promote cellular uptake of HA-MEA-s-s-TGA/PAMAM@DOX by HA receptor-mediated endocytosis. After internalization into tumor cells, the outer shell of the internalized nanocomplex was disassembled in endo-lysosomes via the destruction of disulfide linkages to re-expose PAMAM drug core. This action induced release of the encapsulated DOX and facilitated endo-lysosomal escape through the synergistic action of the proton sponge effect and cationic–anionic interaction between protonated PAMAM and endo-lysosome membranes. In vitro release profiles demonstrated the intracellular environment-responsive release behavior of DOX from this nanocomplex, with a cumulative release of 80% within 4 days in a simulated tumor intracellular microenvironment, whereas the surface charge changed from − 18.82 mV to + 10.95 mV. The MTT assay revealed the good biocompatibility of the negatively charged nanocomplex and efficient toxicity against HeLa cells. The designed pH/GSH dual-responsive nanocomplex could be an efficacious and safe delivery platform for cancer therapy. Graphical abstract
研究领域:
纳米技术
·
药学
·
癌症治疗
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）