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Fluorescent probes have long been regarded as tools for imaging living organisms with advantages such as high sensitivity, good designability and multifunctional potential. Many fluorescent probes, especially the probes based on aggregation-induced emission (AIE) dyes, have received increasing attention since the AIE phenomenon was discovered. These AIE dye-based fluorescent probes could elegantly overcome the notorious quenching effect caused by aggregation of conventional organic dyes. However, it is still difficult to directly apply these AIE-active dyes for biomedical applications owing to their hydrophobic nature. Therefore, the development of novel and facile strategies to endow them with water dispersibility is of critical importance. In this work, we exploit an efficient and simple strategy to fabricate an AIE dye-based fluorescent copolymer through the combination of reversible addition-fragmentation chain transfer and the Biginelli reaction. Moreover, the copolymer can self-assemble to fluorescent polymeric nanoparticles (FPNs) in water solution. Hydrophilic poly(PEGMA-co-AEMA) was reacted with the AIE-active dye 4',4‴-(1,2-diphenylethene-1,2-diyl)bis([1,1'-biphenyl]-4-carbaldehyde (CHO-TPE-CHO) to form amphiphilic luminescent polymers using urea as the connection bridge. The successful synthesis of the final products (poly(PEGMA-co-AEMA-TPE) FPNs) was confirmed by various instruments. Furthermore, Transmission electron microscopy (TEM) images manifest that poly(PEGMA-co-AEMA-TPE) copolymers will self-assemble into spherical nanoparticles in aqueous environments with sizes between 100 nm and 200 nm. The cell uptake and bioimaging experiment confirm that poly(PEGMA-co-AEMA-TPE) FPNs have excellent biocompatibility and emit strong green fluorescence in a cellular environment. Thus, poly(PEGMA-co-AEMA-TPE) FPNs are excellent candidates for biomedical applications., (Copyright © 2018. Published by Elsevier Inc.)

Fluorescent polymeric nanoparticles (FPNs) with aggregation-induced emission (AIE) property have received increasing attention and possess promising biomedical application potential in the recent years. Many efforts have been devoted to the fabrication methodologies of FPNs and significant advance has been achieved. In this contribution, a novel strategy for the fabrication of AIE-active amphiphilic copolymers is reported for the first time based on the Ce(IV) redox polymerization. As an example, ene group containing AIE-active dye (named as Phe-alc) is directly grafted onto a water soluble polymer polyethylene glycol (PEG) in H 2 O/THF system under low temperature. Thus-obtained amphiphilic fluorescent polymers will self-assemble into FPNs with ultra-low critical micelle concentration, ultra-brightness, and great water dispersibility. Biological evaluation results suggest that the PEG-poly(Phe-alc) possess excellent biocompatibility and can be used for tracing their behavior in cells using confocal laser scanning microscope. These features make PEG-poly(Phe-alc) FPNs promising candidates for many biomedical applications, such as cell imaging, drug delivery vehicles, and targeted tracing. More importantly, many other functional groups can also be incorporated into these AIE-active FPNs through the redox polymerization. Therefore, the redox polymerization should be a facile and effective strategy for fabrication of AIE-active FPNs., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Polymerization-induced phase separation is comparatively applied to fabricating a superhydrophobic micro/nano surface by microwave and ultraviolet (UV) irradiation. The monolithic coatings can be tailored easily on different substrates with excellent chemical and mechanical stability in rigid conditions. Importantly, the patterned filter paper is successfully used for the colorimetric detection of nitrite handily.

Self-assembly of amphiphilic luminescent copolymers is a general route to fabricate fluorescent polymeric microparticles (FPMs). In this work, the FPMs with aggregation-induced emission (AIE) feature were fabricated via the combination of the chain transfer free radical polymerization and “one-pot” multicomponent reaction, which conjugated the aldehyde-containing AIE active dye AIE (CHO-An-CHO) and amino-terminated hydrophilic polymer (ATPPEGMA) using mercaptoacetic acid (MTA) as the “lock” molecule. The structure, chemical compositions, optical properties as well as biological properties of the PPEGMA-An-PPEGMA FPMs were characterized and investigated by means of a series of techniques and experiments in detail. We demonstrated the final copolymers showed amphiphilic properties, strong yellow fluorescence and high water dispersibility. Biological evaluation suggested that PPEGMA-An-PPEGMA FPMs possess low cytotoxicity and can be used for cell imaging. More importantly, many other AIE active FPMs are expected to be fabricated using the similar strategy because of the good substrate and monomer applicability of the multicomponent reaction and chain transfer living radical polymerization. Therefore, we could conclude that the strategy described in this work should be of great interest for fabrication of multifunctional AIE active nanoprobes for biomedical applications. [ABSTRACT FROM AUTHOR]

We present a microwave-assisted one-pot polymerization with three-components of alkynes, aldehydes and amines for the synthesis of new amino-functionalized optoelectronic polymers. The polymerization of diynes ( 1a− 1c, dialdehydes ( 2a and 2b and dibenzylamine catalyzed by InCl was carried out smoothly within 1 h under microwave radiation, yielding four soluble polymers with high molecular weights. The resulting polymers P1 and P2 could be easily dissolved in alcohol and thus utilized as the cathode interlayer for polymer solar cells (PSCs). Compared with the control device, the PSCs with P1 and P2 as the cathode interlayer and PTB7-Th:PCBM as the photoactive layer exhibited significantly higher power conversion efficiencies (PCEs) of 9.49% and 9.16%, respectively. These results suggest that this polycoupling reaction is an efficient approach to construct three-component polymers for the practical applications. [ABSTRACT FROM AUTHOR]

In this study, a facile surface functionalization method was applied to synthesize poly-levodopa (PDOPA)-modified silica nanocomposites (denoted as SiO-PDOPA). The adsorption capacity of SiO-PDOPA was found to be higher than that of unmodified SiO NPs. The successful preparation of SiO-PDOPA was confirmed by Fourier transform infrared spectroscopy, transmission electron microscopy, and thermo gravimetric analysis. The adsorption behavior was investigated using SiO-PDOPA as adsorbents and Cu as a model heavy metal pollutant. Various adsorption parameters, including contact time, solution pH, temperature, and initial Cu concentrations were studied. The results showed that pH could markedly affect the adsorption process of SiO-PDOPA to Cu. The optimum pH for Cu adsorption was found to be 7.0. The adsorption kinetic data were analyzed using pseudofirst-order, pseudosecond-order, and intraparticle diffusion models. The adsorption isotherms could be described by Langmuir and Freundlich isotherm models. The fitting results showed that the adsorption kinetics and isotherms were better described by the pseudosecond-order and Langmuir model, respectively. The values of thermodynamics constants, including entropy change (Δ S ), enthalpy change (Δ H ), and Gibbs free energy (Δ G ) were determined at different temperatures. Results suggested that the adsorption process of SiO-PDOPA to Cu is a feasible, endothermic, and spontaneous process. [ABSTRACT FROM AUTHOR]

Surface modification of graphene oxide has attracted increasing attention in recent years. In this article, a green, facile and efficient method was developed to modify graphene oxide with polymers via combination of mussel inspired chemistry and Michael addition reaction. Graphite powder was first oxidized and exfoliated into a single layer of slices through a modified Hummers method, then coated with polydopamine, which was formed via self-polymerization of dopamine in alkaline solution. Next, the intermediate (GO–PDA) was grafted by polyacrylic acid, which was synthesized via reversible addition–fragmentation chain transfer polymerization, through Michael addition reaction. The resulting products were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, transmission electron microscopy and X-ray photoelectron spectrometry. The characterization results indicated the success of adhesion and grafting of PDA and polyacrylic acid, respectively. The resulting products also exhibited sensitivity to pH. Apart from the polymer demonstrated in this work, many other polymers may also be grafted onto graphene oxide through this strategy when different monomers were adopted. Furthermore, this strategy can also be extended to surface modification of many other materials for the versatility of mussel inspired chemistry. It is therefore recommended that the novel strategy developed in this work should be a general strategy for fabrication of various functional nanocomposites, which can exhibit better performance for different applications. [ABSTRACT FROM AUTHOR]

In this work, a novel strategy for surface modification of carbon nanotubes (CNTs) was developed via combination of mussel inspired chemistry and chain transfer free radical polymerization. First, pristine CNTs were functionalized with polydopamine (PDA), which is formed via self-polymerization of dopamine in alkaline conditions. These PDA functionalized CNTs can be further reacted with amino-terminated polymers (named as PDMC), which was synthesized through chain transfer free radical polymerization using cysteamine hydrochloride as chain transfer agent and methacryloxyethyltrimethyl ammonium chloride as the monomer. PDMC perfectly conjugated with CNT-PDA was ascertained by a series of characterization techniques including transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). The dispersibility of obtained CNT nanocomposites (named as CNT-PDA-PDMC) was further examined. Results showed that the dispersibility of CNT-PDA-PDMC in aqueous and organic solutions was obviously enhanced. Apart from PDMC, many other amino-terminated polymers can also be used to functionalization of CNTs via similar strategy. Therefore, the method described in this work should be a general strategy for fabrication various polymer nanocomposites. [ABSTRACT FROM AUTHOR]

Polymerization-induced phase separation is comparatively applied to fabricating a superhydrophobic micro/nano surface by microwave and ultraviolet (UV) irradiation. The monolithic coatings can be tailored easily on different substrates with excellent chemical and mechanical stability in rigid conditions. Importantly, the patterned filter paper is successfully used for the colorimetric detection of nitrite handily. [ABSTRACT FROM AUTHOR]

In this study, we developed a new procedure to prepare monodispersed functionalized SiO 2 (SiO 2 -PDA-PDMC) composites via mussel inspired chemistry and surface initiated atom transfer radical polymerization (SI-ATRP). Samples were characterized by transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and thermal gravimetric analysis (TGA) measurements. TEM results showed that spherical morphology was unchanged after the functionalization. FT-IR results confirmed the successful modification with polydopamine (PDA) and the presence of poly-([2-(Methacryloyloxy) ethyl] trimethylammonium chloride) (PDMC) layer on the surface of SiO 2 spheres. TGA data showed that the PDMC account for about 12.12 wt% in the sample of SiO 2 -PDA-PDMC composites. The XPS analysis further confirmed the existence of PDMC on the surface of SiO 2 -PDA-PDMC composites. The obtained SiO 2 -PDA-PDMC composites were used as adsorbent for the removal of Congo red (CR) from aqueous solution to evaluate the performance in environment application. The effect of contact time, solution pH, initial CR concentration and temperature on the adsorption of CR onto SiO 2 -PDA-PDMC composites was investigated. Adsorption results demonstrated that adsorption of CR onto SiO 2 -PDA-PDMC composites was a fast and efficient process. The adsorption equilibrium reached within 60 min, and the adsorption process followed the pseudo-second-order model. The experimental data of isotherms were better described by the Freundlich model. Thermodynamic study depicted the endothermic nature of adsorption and the process was spontaneous. Results from the effect of solution pH on the CR adsorption showed that the acidic condition favors the adsorption and provided evidence for the contribution of PDMC on the SiO 2 -PDA-PDMC composites in the removal of CR. This study suggests SiO 2 -PDA-PDMC composites can be developed as a new adsorbent for the removal of anionic dyes from aqueous solution. [ABSTRACT FROM AUTHOR]

Mesoporous silica nanoparticles have attracted considerable research attention due to their various applications. Surface modification of these mesoporous silica nanoparticles with polymers not only can improve their water dispersity but can also endow several new functions, such as drug loading and delivery or targeting capability. In this work, we report a novel strategy for the direct surface grafting of phospholipid choline-containing copolymers onto Santa Barbara Amorphous-15 (SBA-15) through surface-initiated chain transfer free radical polymerization. The SBA-15 was synthesized by hydrolysis of tetraethoxysilane in the presence of poly(ethylene glycol)- block -poly(propylene glycol)- block -poly(ethylene glycol) (P123) under acidic synthetic conditions. Next, SBA-15 was subsequently modified with thiol groups by co-condensation with γ-mercaptopropyltrimethoxysilane to obtain SBA-15-SH. Finally, the copolymers were grafted on SBA-15-SH through chain transfer free radical polymerization using 2-methacryloyloxy ethyl phosphorylcholine (MPC) and itaconic acid (IA) as monomers. The SBA-15-based polymer composites (SBA-15-SH-poly(MPC- co -IA)) were used as matrices for controlled release of cisplatin (CDDP). The data from a series of characterization techniques indicated that the monomers were successfully grafted onto SBA-15. The resultant SBA-15-SH-poly(MPC- co -IA) composites showed many remarkable physicochemical properties, such as high water dispersity, desirable biocompatibility and high drug loading capacity. These features provide the SBA-15-SH-poly(MPC- co -IA) composites with considerable potential for biomedical applications. [ABSTRACT FROM AUTHOR]

As a new type of mesoporous silica materials with large pore diameter (pore size between 2 and 50 nm) and high specific surface areas, SBA-15 has been widely explored for different applications especially in the biomedical fields. The surface modification of SBA-15 with functional polymers has demonstrated to be an effective way for improving its properties and performance. In this work, we reported the preparation of PEGylated SBA-15 polymer composites through surface-initiated chain transfer free radical polymerization for the first time. The thiol group was first introduced on SBA-15 via co-condensation with γ-mercaptopropyltrimethoxysilane (MPTS), that were utilized to initiate the chain transfer free radical polymerization using poly(ethylene glycol) methyl ether methacrylate (PEGMA) and itaconic acid (IA) as the monomers. The successful modification of SBA-15 with poly(PEGMA- co -IA) copolymers was evidenced by a series of characterization techniques, including 1 H NMR, FT-IR, TGA and XPS. The final SBA-15-SH- poly(PEGMA- co -IA) composites display well water dispersity and high loading capability towards cisplatin (CDDP) owing to the introduction of hydrophilic PEGMA and carboxyl groups. Furthermore, the CDDP could be released from SBA-15-SH-poly(PEGMA- co -IA)-CDDP complexes in a pH dependent behavior, suggesting the potential controlled drug delivery of SBA-15-SH-poly(PEGMA- co -IA). More importantly, the strategy should be also useful for fabrication of many other functional materials for biomedical applications owing to the advantages of SBA-15 and well monomer adoptability of chain transfer free radical polymerization. [ABSTRACT FROM AUTHOR]

The development of simple and effective methods for synthesis of fluorescent polymeric nanoparticles (FPNs) with aggregation-induced emission (AIE) plays an important role for the biomedical applications of AIE-active FPNs. In present work, we developed a facile strategy for the fabrication of AIE-active FPNs by a post-polymerization method based on the microwave-assisted Kabachnik–Fields (KF) reaction, which can conjugate with poly(PEGMA-NH 2 ), AIE-active dye (TPE-CHO) and diethyl phosphate (DP) under microwave irradiation within 5 min. The characterization results confirm that PEGMA-TPE FPNs are successfully prepared through the microwave-assisted KF reaction. The resultant AIE-active FPNs show high water dispersity, intensive fluorescence and low cytotoxicity. These features make these AIE-active FPNs great potential for biomedical applications. Moreover, the microwave-assisted KF reaction is simple, fast, atom economy that should be a general strategy for the fabrication of various multifunctional AIE-active FPNs. We believe this work will open up a new avenue for the preparation of AIE-active functional materials with great potential for different applications. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS 2 ) is a novel type of two-dimensional nanomaterial, which has attracted great research attention for its excellent physicochemical properties and possible applications. In this work, we prepared a novel MoS 2 composite (MoS 2 -PDOPA) through the self-polymerization of levodopa (DOPA) on the surface of MoS 2 under a weak alkaline solution. The obtained samples, including pure MoS 2 and MoS 2 -PDOPA composite were characterized by energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS) analyses. The potential environmental applications of MoS 2 -PDOPA were evaluated by using MoS 2 -PDOPA as adsorbent to remove methylene blue (MB) from aqueous solution. Batch experiments were carried out to investigate the effect of various operational parameters such as contact time, initial MB concentration, solution pH and temperature on the adsorption of MB by MoS 2 -PDOPA. According to the adsorption kinetics, isotherms and thermodynamics analysis, the MB adsorption onto MoS 2 -PDOPA follows the intraparticle diffusion model and Langmuir isotherm model, and the MB adsorption process is spontaneous and endothermic. The maximum adsorption capacity of MoS 2 -PDOPA is calculated to be 244.03 mg/g at 298 K. As compared with unmodified MoS 2 , the adsorption capacity of MoS 2 -PDOPA is obviously improved. Taken together, we developed a facile method to prepare MoS 2 -PDOPA composites based on mussel inspired chemistry. The resultant composites could be utilized as efficient adsorbents with great potential for environmental adsorption applications. [ABSTRACT FROM AUTHOR]

Surface modification of mesoporous silica nanoparticles (MSNs) with functional polymers has become one of the most interest topics over the last decade. Among various surface modification strategies, surface-initiated atom transfer radical polymerization (ATRP) has been regarded as one of the most effective methods. However, the typical ATRP strategy is relied on the transition metal ions and their organic ligands as the polymerization catalyst systems. In this work, a novel surface-initiated ATRP method was established for surface functionalization of MSNs using 10-Phenylphenothiazine (PTH) as the catalyst, 2-methacryloyloxyethyl phosphorylcholine (MPC) and itaconic acid (IA) as the monomers. We demonstrated that photo-induced ATRP is very effective for preparation of polymer functionalized MSNs (MSNs-NH 2 -poly(IA- co -MPC)). More importantly, MSNs-NH 2 -poly(IA- co -MPC) displayed well water dispersity, low cytotoxicity, high loading capability and controlled release behavior towards cisplatin. Furthermore, the method based on photo-induced surface-initiated ATRP could effectively overcome the drawbacks of conventional ATRP, which may involve in the residue of transition metal ions, high polymerization temperature, long polymerization term and complex experimental procedure. Therefore, this strategy described above is of great interest for fabrication of multifunctional polymer composites for various applications. [ABSTRACT FROM AUTHOR]

Polymeric fluorescent organic nanoparticles (polymer-FONs) have raised considerable research attention for biomedical applications owing to their advantages as compared with fluorescent inorganic nanoparticles and small organic molecules. In this study, we presented an efficient, facile and environment-friendly strategy to produce polymer-FONs, which relied on the self-polymerization of dopamine and polyethyleneimine (PEI) in rather mild conditions. To obtain the final polymer-FONs, aldehyde group-containing copolymers (named as poly(UA- co -PEGMA)) were synthesized by reversible addition–fragmentation chain-transfer polymerization using polyethylene glycol methyl ether methacrylate (PEGMA) and 1-undecen-10-al (UA) as monomers. The dopamine was conjugated onto poly(UA- co -PEGMA) through a multicomponent reaction between UA and dopamine to obtain poly(UA- co -PEGMA)-DA, which was further utilized for preparation of polymer-FONs through self-polymerization of dopamine and PEI. 1 H nuclear magnetic resonance, Fourier transform infrared spectroscopy, transmission electron microscopy and fluorescence spectroscopy were employed to characterize the structure, morphology, compositions and optical properties of these polymer-FONs. Cell viability and cell uptake behavior results suggested that these polymer-FONs possess good biocompatibility and can be potentially utilized for biomedical applications. More importantly, the method can be also applied to fabricate many other multifunctional polymer-FONs with great potential for biomedical applications. [ABSTRACT FROM AUTHOR]

Nanodiamond (ND) is a novel class of carbon nanomaterials, which has been extensively investigated for biomedical applications because of its small size, high surface area and excellent biocompatibility. However, the biomedical applications of unmodified ND are still largely restricted because of their poor dispersibility in both aqueous and organic medium. In this work, we reported a novel strategy for the surface modification of ND via reversible addition fragmentation chain transfer (RAFT) polymerization. For preparation of the PEGylated ND (pPEGMA-ND), chain transfer agent (CTA) was immobilized onto ND through reaction between the hydroxyl group of ND and the carboxyl group of CTA, which was used as the initiator for surface-initiated RAFT polymerization. The successful preparation of pPEGMA-ND was characterized by nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectra and thermal gravimetric analysis in detail. Results demonstrated that pPEGMA-ND exhibited enhanced water dispersibility and desirable biocompatibility, making it promising for biomedical applications. [ABSTRACT FROM AUTHOR]

Silica nanoparticles have become one of the most promising nanomaterials for a vast of applications. In this work, a novel strategy for surface modification of silica nanoparticles has been developed for the first time via combination of mussel inspired chemistry and Michael addition reaction. In this procedure, thin polydopamine (PDA) films were first coated on the bare silica nanoparticles via self-polymerization of dopamine in alkaline condition. And then amino-containing polymers were introduced onto the PDA coated silica nanoparticles through Michael addition reaction, that are synthesized from free radical polymerization using poly(ethylene glycol) methyl methacrylate (PEGMA) and N -(3-aminopropyl) methacrylamide (NAPAM) as monomers and ammonium persulfate as the initiator. The successful modification of silica nanoparticles was evidenced by a series of characterization techniques. As compared with the bare silica nanoparticles, the polymers modified silica nanoparticles showed remarkable enhanced dispersibility in both aqueous and organic solution. This strategy is rather simple, effective and versatile. Therefore, it should be of specific importance for further applications of silica nanoparticles and will spark great research attention of scientists from different fields. [ABSTRACT FROM AUTHOR]