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Aggregation-induced emission (AIE) is an abnormal phenomenon, which has been extensively explored for various applications. Taken advantage of the unique AIE feature, a number of luminescent nanoprobes with strong fluorescence intensity could thus be fabricated through different strategies; however, the fabrication of AIE-active carbohydrate polymers is still challenge owing to the poor solubility of carbohydrate polymers in most of organic solvents. In this work, a rather facile strategy has been developed for fabricating AIE-active sodium hyaluronate (Sh) through the formation of dynamic phenyl borate between the phenylboronic acid groups of AIE dye (An-B(OH) 2 )) and Sh in a “one-pot” route. This reaction could occur under low temperature, air atmosphere and in the present water. The physicochemical properties, biocompatibility, biological imaging and drug delivery performance of the final An-Sh fluorescent organic nanoparticles (FNPs) were confirmed by different characterization techniques. Results suggested that An-Sh FNPs possess high water dispersibility, strong fluorescence, and good biocompatibility. These excellent properties make An-Sh FNPs great potential for biological imaging and controlled drug delivery applications. In conclusion, we have developed a facile one-pot strategy for the preparation of AIE-active FNPs through the formation of dynamic bonds in rather mild experimental conditions. The outstanding properties and performance of An-Sh FNPs make them promising candidates for biological imaging and controlled drug delivery applications. [ABSTRACT FROM AUTHOR]

Aggregation-induced emission (AIE) active fluorescence polymeric nanoparticles (FPNs) have recently received increasing interests for biomedical applications such as cell imaging, drug delivery, disease diagnosis and treatment. Fabricated strategies of AIE-active FPNs with high efficiency, simplification and tenderness are still passionately pursued to promote the development of theranostic systems. In this work, we develop a facile method for the preparation of AIE-active FPNs by adopting Ce(IV)/HNO 3 redox polymerization under near room temperature. Thus-prepared FPNs (named as PEG-PLC-1) possess unique AIE feature, great water dispersity, excellent biocompatibility and biodegradability because of the conjugation of ultra-bright AIE dye (PhE-alc) and biodegradable PEG-PCL linear copolymers. The 1 H nuclear magnetic resonance (NMR) spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), UV–Visible and fluorescence spectrometers were used to confirm the successful fabrication of AIE-active FPNs. Cell viability and cellular uptake behavior of PEG-PLC-1 FPNs were further investigated for their potential biomedical applications. Results demonstrated that PEG-PLC-1 FPNs are high water dispersity, intensive luminescence and low cytotoxicity, making them very attractive for biomedical applications. More importantly, the method for the fabrication of AIE-active biodegradable FPNs can be occurred under rather facile conditions (e.g., low temperature, free of metal catalysts, common chain transfer agent and aqueous solution) and are specially used for fabrication of AIE-active polysaccharides with poor organic solubility. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Fluorescent carbon nanoparticles (FCNs) have gradually become the most promising alternative candidates to other traditional fluorescent nanomaterials for biological applications on account of their excellent fluorescence property and remarkable biocompatibility. Although many methods have reported on the preparation of FCNs, to date, no studies have reported the preparation of polymers of functionalized FCNs. A high-efficiency method was developed in this work to synthesize high-quality poly(ethylene oxide) (PEG)-functionalized FCNs from cigarette ash and thiol group-containing PEG via a facile one-pot ultrasonic irradiation treatment. A series of characterization techniques demonstrated the uniform nanoscale size, good fluorescence stability, high water dispersibility and remarkable biocompatibility of the generated FCNs. Furthermore, cell imaging was easily achieved at high resolution using the synthetic FCNs as probes, which validates their potential for bioimaging applications. In summary, an efficient one-pot strategy is reported for the first time on the preparation of PEG-functionalized FCNs with the assistance of ultrasonic irradiation. This method should be of great research interest for the fabrication of other polymer-functionalized FCNs with designable properties and functions. [ABSTRACT FROM AUTHOR]

Carbon quantum dots (CDs) have standout as one of the most important carbon nanomaterials owing to their small size, optical properties, biocompatibility and low toxicity. These CDs have been extensively explored for various applications especially in the biomedical fields. Although great efforts have been devoted to the fabrication of CDs through both top-down and bottom-up methods, most of these CDs exhibited blue emission under UV light irradiation. In this work, we reported a novel, green, economic approach for preparation of nitrogen doped CDs by directly microwave-assisted heating small organic molecules at 120 °C for 5 min using Glu and amino group of MPD as the precursors and ethylene glycol as solvent. Thus prepared CDs emit green fluorescence when they were irradiated under 365 nm UV light. Compared with other synthetic methods, this microwave-assisted heating method does not require strict reaction conditions and is easy for operation. The CDs display unique luminescence properties, high water dispersibility and good biocompatibility. These remarkable features make CDs great potential for various biomedical applications. Taken together, a microwave-assisted heating method has been developed for bottom-up preparation of green emission CDs in a rather mild route. Owing to the facile experimental procedure and outstanding features of CDs, this work will open up a new avenue for fabrication and biomedical applications of CDs. [ABSTRACT FROM AUTHOR]

In recent years, the fluorescent polymeric nanoparticles (FPNs) with aggregation-induced emission (AIE) feature have been extensively exploited in various biomedical fields owing to their advantages, such as low toxicity, biodegradation, excellent biocompatibility, good designability and optical properties. Therefore, development of a facile, efficient and well designable strategy should be of great importance for the biomedical applications of these AIE-active FPNs. In this work, a novel method for the fabrication of AIE-active FPNs has been developed through the self-catalyzed photo-initiated reversible addition fragmentation chain transfer (RAFT) polymerization using an AIE dye containing chain transfer agent (CTA), which could initiate the RAFT polymerization under light irradiation. The results suggested that the final AIE-active FPNs (named as TPE-poly(St-PEGMA)) showed great potential for biomedical applications owing to their optical and biological properties. More importantly, the method described in the work is rather simple and effective and can be further extended to prepare many other different AIE-active FPNs owing to the good monomer adoptability of RAFT polymerization. [ABSTRACT FROM AUTHOR]

Fluorescent organic nanoparticles (FONs) with aggregation-induced emission (AIE) features have recently emerged as promising fluorescent probes for biomedical applications owing to their excellent optical properties, designability and biocompatibility. Significant progress has been made recently for synthesis and biomedical applications of these AIE-active FONs. However, only very limited reports have demonstrated the fabrication of biodegradable AIE-active FONs with red fluorescence emission. In this study, a novel strategy has been developed for the preparation of biodegradable AIE-active polyurethanes (PUs) through a two-step polymerization, in which the diisocyanate-terminated polyethylene glycol (NCO-PEG-NCO) was synthesized and subsequently conjugated with diamine-containing AIE dye (NH 2 -Phe-NH 2 ). The successful synthesis of AIE-active Phe-PEG 2000 PUs is evidenced by a series of characterization techniques. Because of the formation of AIE-active amphiphilic PUs, the final copolymers can self-assemble into spherical nanoparticles, which exhibit strong luminescence and high water dispersion. The biological evaluation results suggest that the AIE-active Phe-PEG 2000 FONs possess low toxicity and desirable cell permeability. Therefore, we anticipate that these AIE-active FONs with biodegradable potential will trigger much research enthusiasm and effort toward the creation of new AIE-active materials with improved properties for various biomedical applications. [ABSTRACT FROM AUTHOR]

Luminescent polymeric nanoparticles (LPNs) with aggregation-induced emission (AIE) feature have emerged as the most promising candidates for biological imaging owing to their unique AIE feature, great water dispersity, strong fluorescence, low cytotoxicity and biocompatibility. Although numerous successful strategies for construction of AIE-active LPNs have been developed, the preparation of dynamic linkages containing AIE-active LPNs based on multicomponent reactions has been rarely reported. In this work, we report a facile method for the formation of AIE-active LPNs via a one-pot conjugation of PEG-B(OH) 2 , 1-thioglycerol and AIE-active dye PhE-alc in short time under rather mild reaction conditions (e.g. ambient temperature, air atmosphere, absent of metal catalysts and in the present of water). The successful formation of AIE-active mPEG-PhE LPNs was confirmed by different characterization techniques in details. The great optical and biological properties certified their applicable for biological imaging application. More importantly, the novel method for the formation of AIE-active LPNs is rather simple, high efficiency and atom economy, which greatly enriched their practical biomedical applications. [ABSTRACT FROM AUTHOR]

Fluorescent polymeric nanoparticles (FPNs) with aggregation-induced emission (AIE) characteristics have attracted much attention for biomedical applications due to their remarkable AIE feature, high water dispersity and desirable biocompatibility. The development of facile and effective strategies for fabrication of these AIE-active FPNs therefore should be of great importance for their biomedical applications. In this work, we reported that a catalyst-free thiol-yne click reaction can be utilized for fabrication of AIE-active FPNs in short reaction time and even without protection of inert gas. The results indicated that the obtained AIE-active amphiphilic copolymers (PEGMA-PhE) can readily self-assemble into luminescent nanoparticles (PEGMA-PhE FPNs) with high water dispersity, uniform size and morphology, red fluorescence. Cell viability examination and cell uptake behavior of PEGMA-PhE FPNs confirmed that these AIE-active FPNs possess low toxicity towards cells and can be easily internalized by cells through non-specific route. Therefore the remarkable properties of PEGMA-PhE FPNs such as high water dispersity, AIE-active fluorescence and nanoscale size as well as excellent biocompatibility make them promising for biomedical applications. [ABSTRACT FROM AUTHOR]

Aggregation-induced emission (AIE) phenomenon has attracted great attention recently and been extensively explored for biomedical applications. Nevertheless, the direct utilization of AIE-active dyes for biomedical applications has demonstrated to be enormous challenge owing to the hydrophobic nature of these AIE-active dyes. In this work, we reported the fabrication of amphiphilic AIE-active copolymers through the specific host-guest interaction between β cyclodextrin (β-CD) and an adamantine terminating tetraphenylethene derivative (TPE-Ad). In this construction system, β-CD was acted as the bridge to link TPE-Ad with PEG. The TPE-β-CD-PEG copolymers were characterized by various equipments in detail. Cytocompatibility and cell uptake behavior of TPE-β-CD-PEG were also examined to evaluate their biomedical application potential. Results demonstrated that TPE-β-CD-PEG copolymers were prone to self-assemble into luminescent nanoparticles, which exhibited high water dispersity, AIE feature and excellent biocompatibility. These features endowed TPE-β-CD-PEG great potential for biomedical 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]

The fabrication of luminescent polymeric nanoparticles with aggregation induced emission (AIE) properties has been extensively investigated in recent years for their distinct optical properties, biocompatibility and designability. Although a number of AIE-active nanoparticles have been fabricated previously, the AIE-active nanoprobes based on carbohydrate polymers have received only limited attention. In this work, we reported for the first time that AIE-active organic nanoparticles could be prepared via a facile one-step strategy. To fabricate these AIE-active nanoparticles, the AIE dye 9,10-bis (divinylphenylboronic acid) anthracene (An-B(OH) 2 ) terminated with phenylboronic acid was synthesized using anthracene as core chemical structure. After mixing with the An-B(OH) 2 and dextran, the resultant products (An-Dex) can be obtained through formation of phenyl borate in aqueous solution, air atmosphere and under room temperature. The intermediates and An-Dex were characterized by a series of characterization techniques including 1 H nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy and fluorescence spectroscopy. To further explore the biomedical applications of these glycosylated AIE-active nanoparticles, cell viability as well as cell imaging performance of An-Dex nanoparticles was also examined. We demonstrated that An-Dex nanoparticles showed strong fluorescent intensity, great water dispersibility and excellent biocompatibility. More importantly, it is well known that phenyl borate is a dynamic bond, which can potentially response to the pH and glucose. Therefore, the resultant AIE-active probes should be promising candidates for different biomedical applications such as biological imaging and controlled drug delivery. [ABSTRACT FROM AUTHOR]

Silica nanoparticles (SiO 2 NPs) have been widely applied in a number of domains because of their inodorous, non-pollution, optical transparency, chemical inert and good biocompatibility. However, to achieve better performance, surface modification of SiO 2 NPs to enhance their dispersibility is generally required. In this paper, a simple, facile and environmental friendly procedure was developed for surface modification of SiO 2 NPs with a biocompatible polymer (polyPEGMA) via combination of mussel inspired chemistry and Michael addition reaction for the first time. Firstly, monodisperse SiO 2 NPs were prepared by using a slightly modified Stöber process. Secondly, SiO 2 NPs were coated with polydopamine (PDA), which was formed through self-polymerization of dopamine in an alkaline aqueous solution. Lastly, the PDA coated SiO 2 NPs were facilely conjugated with polyPEGMA, which were synthesized through chain transfer free radical polymerization using cysteamine hydrochloride as chain transfer agent and poly(ethylene glycol) methyl ether methacrylate as the monomer. The successful preparation of these composites was confirmed by a number of characterization techniques including transmission electron microscopy, Fourier transform infrared spectroscopy, thermal gravimetric analysis and X-ray photoelectron spectroscopy. This method obviously enhance the dispersion of SiO 2 NPs in different organic solvents and aqueous solution. This synthetic method is convenient, effective and environmental friendly, that can be also extended to modify SiO 2 NPs with other functional polymers because of the features of mussel inspired chemistry and chain transfer living polymerization. [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]

A novel strategy for surface modification of multi-walled carbon nanotubes (MWCNT) was developed via combination of mussel inspired chemistry and Michael addition reaction. In this procedure, pristine MWCNT were first coated with polydopamine (PDA) through self polymerization of dopamine. The PDA functionalized CNT (CNT-PDA) were further functionalized with amino-terminated polymers (polyPEGMA), which were synthesized via free radical polymerization using cysteamine hydrochloride as the chain transfer agent and poly(ethylene glycol) monomethyl ether methacylate as the monomer. The successful modification of CNT was ascertained by a series of characterization techniques including transmission electron microscopy, Fourier transform infrared spectroscopy, thermal gravimetric analysis and X-ray photoelectron spectrometry. The polymer modified CNT showed enhanced dispersibility in aqueous and organic solution. Cytotoxicity evaluation of polymers modified CNT showed that these modified CNT are biocompatible with cells. Finally, due to the universal adhesive of PDA and chain transfer free radical polymerization, this strategy developed in this work can also be extended for surface modification of many other nanomaterials with different functional polymers. [ABSTRACT FROM AUTHOR]

Titanium (Ti) and its alloys as bio-implants have excellent biocompatibilities and osteogenic properties after modification of chemical composition and topography via various methods. The corrosion resistance of these modified materials is of great importance for changing oral system, while few researches have reported this point. Recently, oxidative corrosion induced by cellular metabolites has been well concerned. In this study, we explored the corrosion behaviors of four common materials (commercially pure Ti, cp-Ti; Sandblasting and acid etching-modified Ti, Ti-SLA; nanowires-modified Ti, Ti-NW; and zinc-containing nanowires-modified Ti, Ti-NW-Zn) with excellent biocompatibilities and osteogenic capacities under the macrophages induced-oxidizing microenvironment. The results showed that the materials immersed into a high oxidizing environment were more vulnerable to corrode. Meanwhile, different surfaces also showed various corrosion susceptibilities under oxidizing condition. Samples embed with zinc element exhibited more excellent corrosion resistance compared with other three surfaces exposure to excessive H2O2. Besides, we found that zinc-decorated Ti surfaces inhibited the adhesion and proliferation of macrophages on its surface and induced the M2 states of macrophages to better healing and tissue reconstruction. Most importantly, zinc-decorated Ti surfaces markedly increased the expressions of antioxidant enzyme relative genes in macrophages. It improved the oxidation microenvironment around the materials and further protected their properties. In summary, our results demonstrated that Ti-NW-Zn surfaces not only provided excellent corrosion resistance properties, but also inhibited the adhesion of macrophages. These aspects were necessary for maintaining osseointegration capacity and enhancing the corrosion resistance of Ti in numerous medical applications, particularly in dentistry. [ABSTRACT FROM AUTHOR]