Search

Diamond nanoparticles/urethane-based bio-adhesives (ND-U-BA) were synthesized via in-situ polymerization. Chemical structure and curing kinetics of the samples were studied by Fourier-transform infrared spectroscopy. Results showed NDs controlled the curing profile of samples. Thermal and crystalline properties were studied using differential scanning calorimetry and X-ray diffraction analyses. Results indicated hard segments had higher ordering levels in the presence of NDs which is due to the lower hydrogen bonding among polyurethane chains. Mechanical results showed ND-U-BA had higher adhesion strength due to the formation of chemical crosslinks and a controlled curing mechanism. MTT and biodegradation studies showed ND-U-BA had acceptable cell viability and degradation content. • Urethane and diamond nanoparticles/urethane-based bio-adhesives were synthesized. • Results showed ND nanoparticles had controlling effect on curing kinetic of samples. • Cell viability of bio-adhesives was improved with the ND nanoparticles' addition. • Incorporation of ND nanoparticles increased the adhesion strength of bio-adhesive. [ABSTRACT FROM AUTHOR]

Dual temperature- and photoresponsive polymer nanoparticles with sensitivity toward temperature variation through fluorescence resonance energy transfer (FRET)-assisted white light emission (WLE) were synthesized using distillation–precipitation polymerization. A fluorescence chemosensor of temperature, white light-emitting anticounterfeiting inks, and different products for security encryption of confidential documents were prepared on the basis of the FRET mechanism due to an efficient spectral overlap between the emission of the coumarin donor and the absorption of the rhodamine B (RhB) acceptor. At the 150 μL RhB doping, a strong WLE was observed as a consequence of the FRET mechanism between the two complementary colors. Upon increasing the temperature in the range of 25–85 °C, the efficient FRET distance was affected due to squeezing of the thermoresponsive polymer moieties in response to heating; thus, FRET was turned off. These stimulus-responsive fluorescent nanoparticles were finally used as temperature sensors and in security encryption applications by incorporating on/off WLE based on the FRET mechanism and the preparation of white light-emitting paper, silk, and ink through the incorporation of FRET species into paper pulp, impregnation of silk in the colloidal fluorescent nanoparticles, and adding poly-(ethylene glycol) and glycerol to the polymer colloids, respectively. [ABSTRACT FROM AUTHOR]

Herein, we performed grafting of thiol groups to the surface of multi-walled carbon nanotubes. Then, using them (CNTS), zinc oxide (ZnO), ethylene dichloride, and sodium trisulfide (Na2S3), poly(ethylene trisulfide) (PETS) nanocomposites were synthesized via in situ polymerization. After that, the samples were cured at 170°C using a rheometer. The structural characteristics of CNTS were identified by Fourier transform infrared (FTIR), Raman spectroscopies, and X-ray diffraction (XRD). The PETS characteristics were investigated by FT-IR, Raman, X-ray diffraction (XRD), and proton nuclear magnetic resonance (1H NMR). Also, the samples were studied using scanning electron microscopy (SEM), Shore A, tensile tests, and differential scanning calorimetry (DSC). The results showed that CNTS has a significant effect on the curing time of the nanocomposites, so that the curing time decreases with increasing CNTS content. Moreover, the nanocomposites had improved mechanical properties, indicating that they are more resistant to deformation and fracture. In addition, after the curing process, the melting temperature (Tm) was not observed, and by increasing CNTS in composites, the glass transition temperature (Tg) occurs at higher temperatures. Furthermore, the hardness of the samples showed a slight increase with higher CNTS content. [ABSTRACT FROM AUTHOR]

Iron is a crucial trace mineral vital for maintaining optimal human health and well-being. Despite being needed in small amounts, its importance cannot be overstated as it plays an important role in various physiological processes. In this research, we have developed a fluorescence probe utilizing starch functionalized with derivatives of rhodamine 6G to efficiently detect Fe3+ ions. This structure forms selfassembled starch/rhodamine 6G (RS0) fluorescent nanoparticles that exhibit strong fluorescence intensity under ultraviolet light. The ability of Fe3+ ions to increase the fluorescence of the RS0 probe enables the effective detection of Fe3+ ions. Importantly, this fluorescence increasing effect is specific to Fe3+ ions and remains unaffected by the presence of other metal ions. MTT assay against SH-SY5Y cells showed that RS0 was rather cytocompatible. Finally, SH-SY5Y cells were used to measure cell uptake and fluorescence imaging performances of RS0 which showed a good ability for live-cell fluorescence imaging. [ABSTRACT FROM AUTHOR]