Carbon quantum dots (CDs) are promising nanomaterials in biomedical, photocatalytical and photoelectronic applications. However, determining how to explore an ideal precursor for a renewable carbon resource is still an interesting challenge. Here, for the first time, we report that renewable wastes of bagasse as a new precursor were prepared for fluorescent CDs by a hydrothermal carbonization (HTC) process. The characterization results show that such bagasse-derived CDs are monodispersed, contain quasi spherical particles with a diameter of about 1.8 nm and exhibit favorable photoluminescence properties, super-high photostability and good dispersibility in water. Most importantly, bagasse-derived CDs have good biocompatibility and can be easily and quickly internalized by living cancer cells; they can also be used for multicolour biolabeling and bioimaging in cancer cells. It is suggested that bagasse-derived CDs might have potential applications in biomedical and photoelectronic fields.

Kinetic study of the step-growth polymerization of hydroxyl-terminated poly(dimethylsiloxane) (PDMS) and triisocyanate has been done in this work. Kinetic Monte Carlo simulations are performed to understand the experimental investigation of the cross-linked network formation. This approach enables us to afford a visualization of the entire network formation in detail and evaluate its characteristic properties. A comparison between the current simulation results and that from classical theories (e.g., Flory and Macosko−Miller theoretical calculations) is done. In addition, the Cole−Poehlein diffusion model based on the free volume theory, involving a parallel summation of the chemical and diffusional rate coefficients, is used to describe the effect of diffusion-controlled mechanism on polymerization. Moreover, the effect of experimental conditions, such as the ratio of [NCO]/[OH] and the molar mass of PDMS, on network formation kinetics is also investigated. The simulation results demonstrate that the [NCO]/[OH] ratios within the range of 1−1.2 and PDMS with lower molar mass are preferred to prepare a polymer network with a high cross-linking density. It is believed that the current kinetic modeling provides a way for better understanding the kinetics and optimizing the experimental conditions.

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A comprehensive kinetic Monte Carlo algorithm has been developed to investigate the formation process of a polyurethane/poly(methyl methacrylate) (PU/PMMA) interpenetrating polymer network (IPN), in which a component independent strategy is proposed to perform the simulation of simultaneous polycondensation and free radical polymerization. An empiric diffusion model based on the mass fraction of polymer is used to quantify the effect of diffusional limitations on MMA polymerization. Results show that the presence of acrylic monomers has little impact on the formation rate of PU, but the presence of the PU network can accelerate the polymerization of MMA. In addition, the effects of component mass ratio, acrylic cross-linker concentration, and [NCO]/[OH] ratio on the IPN formation kinetics are investigated based on the kinetic model. It is believed that the as-developed modeling strategy can be extended to other IPN systems and provide a better understanding of the interactions between chemically independent networks.

Inaccuracy localization and intrinsic radioresistance of solid tumors seriously hindered the clinical implementation of radiotherapy. In this study, we fabricated hyaluronic acid-functionalized gadolinium oxide nanoparticles (HA-Gd 2 O 3 NPs) via one-pot hydrothermal process for effective magnetic resonance (MR) imaging and radiosensitization of tumors. By virtue of HA functionalization, the as-prepared HA-Gd 2 O 3 NPs with a diameter of 105 nm showed favorable dispersibility in water, low cytotoxicity, and excellent biocompatibility and readily entered into the cytoplasm of cancer cells by HA receptor-mediated endocytosis. Importantly, HA-Gd 2 O 3 NPs exhibited high longitudinal relaxivity (r 1) 6.0 mM −1 S −1 as MRI contrast agents and radiosensitization enhancement in a dosedependent manner. These finds demonstrated that as-synthesized HA-Gd 2 O 3 NPs as bifunctional theranostic agents have great potential in tumors diagnosis and radiotherapy.