Study on the Aggregation of Fluorinated Surfactant FC-134 on the Surface of DNA

AbstractThe aggregation of perfluoroalkylsulfonyl quaternary ammonium iodide (FC134) on DNA was studied by spectral method. The results showed that it is a good way to determine DNA with FC134 by RLS method. This method is reliable, precise and simple. FT-IR spectra and UV-spectra were used to study the mechanisms of the interaction. The results indicated that the conformation of the DNA has changed during the interaction because the microenvironment of DNA changed

Multifunctional magnetized porous silica covered with Poly(2-dimethylaminoethyl methacrylate) for pH controllable drug release and Magnetic Resonance Imaging

The authors described a smart magnetic-targeting drug carrier gamma-Fe2O3@SiO2-PDMAEMA consisting of gamma-Fe2O3 and coated with porous silica, further modified by poly(2-dimethylaminoethyl methacrylate). In this research, the porous silica was first coated with poly(2-dimethyl-aminoethyl methacrylate). The material can be loaded with up to 79 mg g(-1) of Doxorubicin (DOX) and 90 mg g(-1) of rhodamine B (RhoB) (acting as a model drug), which are both greatly larger than reported materials. Cytotoxicity experiments indicated the biocompatibility of gamma-Fe2O3@SiO2-PDMAEMA, which is beneficial as drug carriers. DOX and RhoB were both released rapidly at pH 5.5 but the drug release strongly decreased at pH 7.4. The gamma-Fe2O3@SiO2-PDMAEMA showed an excellent pH-triggered drug release. The possibility of the particles in magnetic resonance imaging (MRI) was discussed and the significant dose-dependent contrast enhancement in T-2-weighted MRI suggested that gamma-Fe2O3@SiO2-PDMAEMA can be potentially applied in T-2 MRI. The fluorescence imaging of gamma-Fe2O3@SiO2-PDMAEMA loaded with RhoB proved the particles can be taken up by cells. All the results exhibited a promising application in safe cancer therapy

The evolution of gadolinium based contrast agents: from single-modality to multi-modality

Gadolinium-based contrast agents are extensively used as magnetic resonance imaging (MRI) contrast agents due to their outstanding signal enhancement and ease of chemical modification. However, it is increasingly recognized that information obtained from single modal molecular imaging cannot satisfy the higher requirements on the efficiency and accuracy for clinical diagnosis and medical research, due to its limitation and default rooted in single molecular imaging technique itself. To compensate for the deficiencies of single function magnetic resonance imaging contrast agents, the combination of multi-modality imaging has turned to be the research hotpot in recent years. This review presents an overview on the recent developments of the functionalization of gadolinium-based contrast agents, and their application in biomedicine applications

Biomass-Based Anion Exchange Membranes Using Poly (Ionic Liquid) Filled Bacterial Cellulose with Superior Ionic Conductivity and Significantly Improved Strength

How to simultaneously improve the ionic conductivity and mechanical properties is a key problem facing currently used anion-exchange membranes (AEMs). Here, novel AEMs were prepared using quaternized bacterial cellulose (QBC) as a dual-functional substrate and then filled with a polymeric ionic liquid (poly(vinylbenzyl) trimethylammonium chloride, PVD) with high ion-exchange capacity through in situ polymerization and crosslinking. The dense quaternary ammonium groups grafted on the surface of BC nanofibers greatly increased the ionic conductivity, while the special three-dimensional network structure of BC significantly enhanced the tensile strength and chemical stability of the obtained PVD filled quaternized BC (QBC/PVD) membranes. The ionic conductivity of QBC/PVD membrane reached as high as 111 mS cm−1 at 80°C, which was 109% higher than that of the pure BC/PVD membrane (only 53 mS cm−1). Moreover, the QBC/PVD membrane exhibited extremely high dry strength of 72.3 MPa and satisfactory wet strength and flexibility, this membrane can hang a container containing 500 g of water when at fully hydrated state. The alkaline direct methanol fuel cell equipped with QBC/PVD output a peak power density of 64 mW cm−2, showing its great application potential as an AEM

Self-assembled magnetic luminescent hybrid micelles containing rare earth Eu for dual-modality MR and optical imaging

In this study, we report new water-soluble multifunctional nanomaterials based on amphiphilic poly(HFMA-co-Eu(AA)3Phen)-g-PEG copolymers and oleic acid modified Fe3O4 nanoparticles. The nanoparticles can self-assemble to form magnetic and luminescent hybrid micelles and show a spherical morphology, paramagnetic properties with a maximum saturation magnetization of 7.05 emu g-1, and a high transverse relaxivity of 340 mM-1 s-1. According to in vivo magnetic resonance imaging (MRI) experiments, excellent contrast of the liver and spleen was achieved after injection of the hybrid micelles. Fluorescence spectra show characteristic emission peaks from the rare earth Eu at 616 nm and vivid red fluorescence can be observed by 2-photon confocal laser scanning microscopy (CLSM). In vivo optical imaging demonstrates the unique fluorescent characteristics of the magnetic and luminescent hybrid micelles in the liver and spleen and the excellent multifunctional properties suggest the possibility of clinical use as nanocarriers in magnetic resonance imaging and optical imaging

Fluorinated Linear Copolyimide Physically Crosslinked with Novel Fluorinated Hyperbranched Polyimide Containing Large Space Volumes for Enhanced Mechanical Properties and UV-Shielding Application

Fluorinated hyperbranched polyimide (FHBPI), a spherical polymer with large space volumes, was developed to enhance fluorinated linear copolyimide (FPI) in terms of mechanical, UV-shielding, and hydrophobic properties via simple blend and thermal imidization methods. FPI possessed superior compatibility with FHBPI, and no obvious phase separation was found. The incorporation of FHBPI led to the formation of physical crosslinked network between FPI and FHBPI, which markedly improved the mechanical properties of the FPI, resulting in maximum enhancement of 83% in tensile strength from 71.7 Mpa of the pure FPI to 131.4 Mpa of the FPI/FHBPI composite film containing 15 wt % of FHBPI. The introduction of FHBPI also changed the surface properties of composites from hydrophilicity to hydrophobicity, which endowed them with outstanding dielectric stability. Meanwhile, the thin FPI/FHBPI composites kept the high transparency in the visible spectrum, simultaneously showing enhanced UV-shielding properties and lifetimes under intense UV ray. This was attributed to the newly formed charge transfer complex (CTC) between FHBPI and FPI. Moreover, the FPI/FHBPI composites possessed preeminent thermal properties. The properties, mentioned above, gave the composites enormous potential for use as UV-shielding coatings in an environment filled with high temperatures and strong ultraviolet rays

Controllable synthesis of up-conversion nanoparticles UCNPs@MIL-PEG for pH-responsive drug delivery and potential up-conversion luminescence/magnetic resonance dual-mode imaging

Rare-earth doped up-conversion nanoparticles (UCNPs) with high uniformity and dispersibility were synthesized by a facile solvothermal method. The conditions of synthesis for NaYF:Yb/Tm were explored, and the NaYF:Yb/Tm particles with the optimal size (about 300 nm) were obtained. Blue emission was observed with the excitation 980 nm near infrared (NIR) laser, indicating that the UCNPs can be potentially used for up-conversion luminescence (UCL) imaging. On basis of the optimal UCNPs, further coated by poly (ethylene glycol) (PEG) functionalized metal-organic frameworks (MOFs), a multifunctional platform UCNPs@MIL-PEG for cancer diagnosis and treatment was established. The core-shell structure was confirmed by TEM images. Doxorubicin (DOX) was selected as drug model and the drug loading of UCNPs@MIL-PEG was found to be 60%. Cytotoxicity indicated that UCNPs@MIL-PEG were highly biocompatible. The DOX release in different pH value revealed an excellent pH-triggered drug release. In addition, the UCNPs@MIL-PEG nanoparticles can be tracked by magnetic resonance imaging (MRI). A clear dose-dependent contrast enhancement in T-weighted MR images indicated the potential act as T MRI contrast agents. The UCNPs@MIL-PEG nanoparticles are expected to be simultaneously used for UCL/MR dual-mode imaging and pH-responsive drug release

“Dual-Key-and-Lock” dual drug carrier for dual mode imaging guided chemo-photothermal therapy

Drug resistance and side effects are the two main problems of chemotherapy. In order to address these big challenges, p-PB@d-SiO2, which has the ability to co-deliver both the hydrophobic drug doxorubicin hydrochloride (DOX) and the hydrophilic drug ibuprofen (IBU), is constructed to achieve synergistic treatment. The drug-loaded nanoparticle consists of porous Prussian blue (p-PB) as the core and dendrimer-like SiO2 (d-SiO2) as the shell, which is further thiolated and coated with polyethylene glycol thiol (HS-PEG) to form the "Dual-Key-and-Lock" drug carrier p-PB@d-SiO2-SS-PEG. The locked drugs can only be released in the presence of cooperative triggers, i.e., a high glutathione concentration (the first key) and an acidic environment (the second key). The "dual key"-triggered release is much more significant in cancer lesions than in normal tissues, reducing side effects. Furthermore, cell viability experiments highlight the superior therapeutic efficacy of the dual-drug-loaded nanoparticles compared with the single-drug systems (60%, 73% and 86% vs. 56%, 68%, and 76% at 100, 200 and 500 μg mL-1, respectively). In vitro and in vivo experiments demonstrate the potential application of p-PB@d-SiO2-SS-PEG for dual-mode fluorescence and magnetic-resonance-imaging-guided chemo-photothermal therapy. The "Dual-Key-and-Lock" drug carrier system exhibits the "1 + 1 > 2" effect, demonstrating its excellent performance in synergy therapy for improved therapeutic efficiency and thereby reducing conventional drug resistance and side effects

Thermally and Chemically Stable Candle Soot Superhydrophobic Surface with Excellent Self-Cleaning Properties in Air and Oil

In this report, a people-considered waste-candle soot generated from incomplete combustion of the middle zone of candle was used to coat the glass slide for fabricating the superhydrophobic surface. The candle soot coating surface followed by deposition of methyltrichlorosilane (MTCS) was characterized through field emission scanning electron microscope, contact angle measurement in air and oil, self-cleaning test, high temperature, and corrosive liquid resistance test and water drop impact experiment, respectively. Interestingly, the candle soot layer after deposition of MTCS presented a coral-like structure and exhibited high water contact angle of 161° and a low sliding angle of 3° in air, which demonstrated that it had excellent superhydrophobicity in air. Of course, the coating also exhibited high water contact angle and low sliding angle in oil. Apart from that, results of high temperature and corrosive liquid resistance tests implied that the superhydrophobic coating can keep stability after treatment by high temperature between 100 and 300 °C and can retain high contact angle when encountering the strongly acidic and basic water, which indicated that it exhibited excellent thermal and chemical stabilities. Moreover, the prepared thermally and chemically stable superhydrophobic coating not only displayed wonderful self-cleaning properties in air and oil but also resisted to water drop impaction after deposition of MTCS, which interconnected the carbon particles via the hydrolysis of MTCS in air. In summary, we provided a fast and cost-efficient method to prepare the superhydrophobic coating with excellent thermal and chemical stabilities, which showed great potential in application of antifouling materials under the high temperature and corrosive condition