Methylene blue removal using modified poly(glycidyl methacrylate) as a low-cost sorbent in batch mode: kinetic and equilibrium studies.

Industrial textile wastewater contains large amounts of cationic dye material. Therefore, a new adsorbent was synthesized as modified poly(glycidyl methacrylate) (mPGMA) with a fluorine group-containing compound 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP). mPGMA was characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectrometer (FTIR). The proposed adsorbent has been used to remove methylene blue (MB) from aqueous solutions by the adsorption process. In further experiments, the removal efficiency of adsorbent in both powder (˂600 µm) and granular form was compared from aqueous solutions by adsorption process. Furthermore, the effects of changing parameters such as adsorbent dosage, contact time, pH, temperature, and initial dye concentration on methylene blue adsorption were investigated. Also, Langmuir, Freundlich, and Temkin isotherms have been used to describe the equilibrium characteristics of adsorption. Finally, the experimental data fitted well by Langmuir isotherm with a maximum adsorption capacity of 17.5 mg g-1. The experimental data were applied to pseudo-first- and second-order models. The experimental results were better fitted for the pseudo-second-order model than the other model. Consequently, the experimental results showed that mPGMA is a suitable low-cost adsorbent with great potential benefit in removing methylene blue from aqueous solutions.

Assessment of knowledge, attitude, and practice of faculty and postgraduates toward Bisphenol A (BPA) exposure in dental care.

Bisphenol A (BPA) is commonly used in resin-based dental materials and is categorised as an endocrine-disrupting compound. This study aimed to evaluate the knowledge, attitudes, and practice toward the use of BPA among faculty members and postgraduate students. In this descriptive study, a validated self-administered questionnaire was used, and 204 dentists were included, with a response rate of 56.2%. The findings revealed that faculty members had significantly better knowledge (p=0.024) and practice (p=0.036) and more positive attitudes (p=0.024) toward BPA exposure. Regression analysis showed a significantly positive effect of attending a workshop/lecture or reading an article about BPA on the participants' total mean knowledge (p<0.001) and practice scores (p<0.001). Furthermore, faculty members showed a significantly more positive attitude (p<0.001) toward BPA exposure. These results emphasise the importance of increased awareness and education concerning BPA exposure to ensure optimal dental care.

Effect of monomer composition and filler fraction on surface microhardness and depth of cure of experimental resin composites.

This study evaluated microhardness profiles and calculated depths of cure at 80% of the surface microhardness of experimental dental resin composites having different base monomer compositions and different filler fractions. Composites were prepared using four different base monomers (bisphenol A-glycidyl methacrylate [Bis-GMA], urethane dimethacrylate [UDMA], ethoxylated bisphenol-A dimethacrylate [Bis-EMA], and Fit-852) with triethylene glycol dimethacrylate (TEGDMA) used as a co-monomer at three filler:resin matrix weight percent fractions (50:50, 60:40, and 70:30). Uncured material was placed in 3D printed molds and light cured for 40 s from the top surface only. Knoop microhardness was measured at the top of the specimen, and at every 0.5 mm up to 4 mm in depth. Microhardness at the surface increased in all experimental composites as the filler fraction increased. When comparing base monomers, microhardness was the highest in UDMA-based composites, while Bis-GMA-based composites showed the lowest values. When comparing depth of cure as a function of base monomer type, both Bis-GMA and Bis-EMA showed significantly lower values than UDMA or Fit-852. Composites having 50 wt% filler showed a significantly higher depth of cure than those with 60 and 70 wt% filler. Base monomer and filler fraction significantly influence microhardness and depth of cure in these experimental composites.

Room-Temperature Self-Healable Blends of Waterborne Polyurethanes with 2-Hydroxyethyl Methacrylate-Based Polymers.

The design of self-healing agents is a topic of important scientific interest for the development of high-performance materials for coating applications. Herein, two series of copolymers of 2-hydroxyethyl methacrylate (HEMA) with either the hydrophilic N,N-dimethylacrylamide (DMAM) or the epoxy group-bearing hydrophobic glycidyl methacrylate were synthesized and studied as potential self-healing agents of waterborne polyurethanes (WPU). The molar percentage of DMAM or GMA units in the P(HEMA-co-DMAMy) and P(HEMA-co-GMAy) copolymers varies from 0% up to 80%. WPU/polymer composites with a 10% w/w or 20% w/w copolymer content were prepared with the facile method of solution mixing. Thanks to the presence of P(HEMA-co-DMAMy) copolymers, WPU/P(HEMA-co-DMAMy) composite films exhibited surface hydrophilicity (water contact angle studies), and tendency for water uptake (water sorption kinetics studies). In contrast, the surfaces of the WPU/P(HEMA-co-GMAy) composites were less hydrophilic compared with the WPU/P(HEMA-co-DMAMy) ones. The room-temperature, water-mediated self-healing ability of these composites was investigated through addition of water drops on the damaged area. Both copolymer series exhibited healing abilities, with the hydrophilic P(HEMA-co-DMAMy) copolymers being more promising. This green healing procedure, in combination with the simple film fabrication process and simple healing triggering, makes these materials attractive for practical applications.

[Inhibition of GMA-induced ubiquitination process in 16HBE malignantly transformed cells on protein CD44 and MMP14].

OBJECTIVE: To observe the effect of the ubiquitination process on the expression of CD44 antigen(CD44) and matrix metalloproteinase-14(MMP14) in human bronchial epithelial(16HBE) malignantly transformed cells induced by glycidyl methacrylate(GMA). METHODS: Successfully resuscitated 16HBE cells were cultured using a final concentration of 8 µg/mL GMA as the treatment group and 1 µg/mL dimethyl sulfoxide as the solvent control group, each time stained for 72 h, and then stained again after an interval of 24 h. After repeating the staining three times, the cells were cultured in passages respectively. The 40th generation(P40) GMA-treated group and the same-generation solvent control group were subjected to soft agar colony formation assay and concanavalin A(ConA) agglutination test to confirm that the 40th generation of GMA-induced malignant transformed 16HBE cells possessed malignant transformed cell characteristics.5, 10, 20, 40, 60 µmol/L anacardic acid were used to inhibit the ubiquitination process of GMA-induced malignant transformed 16HBE cells. The protein expression of CD44 and MMP14 were detected by western blotting, while the transcript levels of CD44, MMP14, and TFAP2A were assessed by real-time fluorescence quantitative PCR(qPCR). RESULTS: (1) In the soft agar colony formation assay, the number of clones formed by the cells in the solvent control group was 22, and the number of clones created by the malignantly transformed cells in the GMA-treated group was 208. In the ConA agglutination test, the cells in the solvent control group were uniformly dispersed in ConA solution, and no obvious agglutination occurred for 30 min, whereas the cells in the GMA-treated group were agglutinated in the 5th min, and the agglutinated cells were larger and more rapidly agglutinated. The agglomerates were more significant and faster, and the sensitivity of agglutination was increased. (2) After differential inhibition of GMA-induced ubiquitination in malignantly transformed 16HBE cells, the expression levels of CD44 and MMP14 were reduced in GMA-induced malignantly transformed 16HBE cells compared with the control group(P<0.05). The transcript levels of MMP14 and CD44 decreased with increasing inhibitor concentration(P<0.05), and the transcript levels of the upstream transcription factor TFAP2A were also simultaneously reduced(P<0.05). CONCLUSION: Inhibition of the cellular ubiquitination process mediates the down-regulation of protein expression and transcriptional expression of CD44 and MMP14 in GMA-induced malignantly transformed 16HBE cells.

Effect of at-home bleaching gels with different thickeners on the physical properties of a composite resin without bisphenol A.

OBJECTIVE: To investigate, in vitro, the influence of at-home bleaching with 16% carbamide peroxide (CP) gels containing different thickeners on the color, gloss, roughness, and microhardness of a composite resin with bisphenol A (BPA) and without bisphenol A (BPA-free). MATERIAL AND METHODS: Cylindrical samples (7 × 2 mm) of a composite resin with BPA (Filtek Z350 XT®; 3M/ESPE) and composite resin BPA-free (Vittra APS®; FGM) were subdivided into six subgroups (n = 12), according to the bleaching gel used: no bleaching (control), commercial gel with 16% CP and carbopol, experimental gel with 16% CP and carbopol, experimental gel with 16% CP and natrosol, experimental gel with carbopol and experimental gel with natrosol. At the end of the experimental phase, the specimens were analyzed for color (ΔE*ab and ΔE00 ), surface roughness (Ra), gloss (GU), and surface microhardness (SMH). The data for all analyzes were submitted to Levene's test, Shapiro-Wilk's test and ANOVA. RESULTS: For ΔE*ab and ΔE00 no statistically significant differences were found between all groups evaluated. Bleaching with experimental 16% CP gel with carbopol resulted in the lowest GU values for both composite resins evaluated. 16% CP experimental gel with natrosol resulted in higher Ra for the BPA composite resin and the bleaching with natrosol resulted in higher Ra for BPA-free. About 16% CP experimental gel with carbopol and 16% CP experimental gel with natrosol resulted in the lowest final SMH for composite resin with BPA. For the BPA-free composite resin, no differences were found between the groups in SMH for the same resin, however they presented the lowest values compared with all others groups. CONCLUSION: The effects on physical properties are dependent on the composition of the composite resin and the thickener/bleaching gel used. The BPA-free composite resin showed less changes after exposure to bleaching agent, although its initial physical properties were worse compared to a bleached BPA. CLINICAL RELEVANCE: The hydrogen peroxide and thickener of the at-home bleaching gel does impact the properties of composites with BPA or BPA-free such as gloss, roughness and surface microhardness, extremely important factors for maintaining an aesthetically and physically satisfactory restoration. BPA-free composite resins have inferior properties after at-home bleaching with different thickeners.

Glycidyl Methacrylate-Based Copolymers as Healing Agents of Waterborne Polyurethanes.

Self-healing materials and self-healing mechanisms are two topics that have attracted huge scientific interest in recent decades. Macromolecular chemistry can provide appropriately tailored functional polymers with desired healing properties. Herein, we report the incorporation of glycidyl methacrylate-based (GMA) copolymers in waterborne polyurethanes (WPUs) and the study of their potential healing ability. Two types of copolymers were synthesized, namely the hydrophobic P(BA-co-GMAy) copolymers of GMA with n-butyl acrylate (BA) and the amphiphilic copolymers P(PEGMA-co-GMAy) of GMA with a poly(ethylene glycol) methyl ether methacrylate (PEGMA) macromonomer. We demonstrate that the blending of these types of copolymers with two WPUs leads to homogenous composites. While the addition of P(BA-co-GMAy) in the WPUs leads to amorphous materials, the addition of P(PEGMA-co-GMAy) copolymers leads to hybrid composite systems varying from amorphous to semi-crystalline, depending on copolymer or blend composition. The healing efficiency of these copolymers was explored upon application of two external triggers (addition of water or heating). Promising healing results were exhibited by the final composites when water was used as a healing trigger.

Microwave-Assisted Synthesis of Modified Glycidyl Methacrylate-Ethyl Methacrylate Oligomers, Their Physico-Chemical and Biological Characteristics.

In this study, well-known oligomers containing ethyl methacrylate (EMA) and glycidyl methacrylate (GMA) components for the synthesis of the oligomeric network [P(EMA)-co-(GMA)] were used. In order to change the hydrophobic character of the [P(EMA)-co-(GMA)] to a more hydrophilic one, the oligomeric chain was functionalized with ethanolamine, xylitol (Xyl), and L-ornithine. The oligomeric materials were characterized by nuclear magnetic resonance and Fourier transform infrared spectroscopy, scanning electron microscopy, and differential thermogravimetric analysis. In the final stage, thanks to the large amount of -OH groups, it was possible to obtain a three-dimensional hydrogel (HG) network. The HGs were used as a matrix for the immobilization of methylene blue, which was chosen as a model compound of active substances, the release of which from the matrix was examined using spectrophotometric detection. The cytotoxic test was performed using fluid extracts of the HGs and human skin fibroblasts. The cell culture experiment showed that only [P(EMA)-co-(GMA)] and [P(EMA)-co-(GMA)]-Xyl have the potential to be used in biomedical applications. The studies revealed that the obtained HGs were porous and non-cytotoxic, which gives them the opportunity to possess great potential for use as an oligomeric network for drug reservoirs in in vitro application.

Development of Azo Dye Immobilized Sulfonated Poly (Glycidyl Methacrylate) Polymer Composite as Novel Adsorbents for Water Treatment Applications: Methylene Blue Immobilization Isotherm, Kinetic, Thermodynamic, and Simulations Studies.

Methylene blue (MB) immobilized onto a sulfonated poly(glycidyl methacrylate) (SPGMA) polymer composite has been developed as a novel adsorbent for water treatment applications. The MB adsorptions onto sulfonated poly(glycidyl methacrylate) polymer characters have been studied. The adsorption isotherms, namely Langmuir and Freundlich, have been investigated. Other isotherm models. As a compromise between the Freundlich and Langmuir isotherm models, such as the D-R isotherm and the Temkin isotherm, have been compared. The results indicated that the adsorption process followed the Freundlich isotherm model, indicating heterogeneous surface site energies and multi-layer levels of sorption. This study selected three linear kinetic models, namely pseudo-first order, pseudo-second order, and Elovich, to describe the MB sorption process using SPGMA negatively charged nanoparticles (430 nm). The obtained data revealed that the adsorption process obeyed the pseudo-second-order kinetic model, suggesting that the rate-limiting step in these sorption processes may be chemisorption. Furthermore, the thermodynamic parameters have been evaluated. Moreover, the interaction of the MB molecules with SPGMA nanoparticles has been simulated using the governing equation that describes ion exchange resin derived from Nernst-Plank equations between two ion species. Finally, the developed MB-SPGMA composite adsorbent (27 mg/g) wastested for the first time for the removal of Cr6+ ions and Mn7+ metal ions from dichromate and permanganate-contaminated waters under mild adsorption conditions, opening a new field of multiuse of the same adsorbent in the removal of more than one contaminant.

A comparative in vitro study on monomer release from bisphenol A-free and conventional temporary crown and bridge materials.

This study aimed to investigate the release of common monomers from two conventional and two bisphenol A (BPA)-free temporary crown and bridge materials. Cylindrical samples of all materials were prepared (N = 90; five samples for each material and cycle of analysis). All samples were immersed in high-performance liquid chromatography (HPLC)-grade water and incubated for 1 h, 12 h, 24 h, and 7 days in an incubation shaker at 37°C and 112 rpm. Extraction was performed in accordance with ISO 10993-12. Eluted monomers were detected and quantified by HPLC coupled with ultraviolet-visible spectroscopy and mass spectrometry (HPLC-UV/Vis-MS). Analysis of BPA was performed by HPLC coupled with ultraviolet-visible spectroscopy (HPLC-UV/Vis) and positive results were verified by HPLC-tandem mass spectrometry (HPLC-MS/MS). Neither bisphenol A-glycidyl methacrylate (Bis-GMA) nor BPA was quantifiable in any of the crown and bridge samples investigated in the present study. However, all samples contained triethylene glycol dimethacrylate (TEGDMA) and/or urethane dimethacrylate (UDMA) after 24 h of incubation. Statistical analysis showed that significantly more UDMA was released from the BPA-free materials than from the conventional materials. All concentrations of UDMA measured were below the effective cytotoxic concentrations previously reported. However, for a few materials, especially BPA-free temporary crown and bridge materials, the levels of UDMA were above previously reported potentially harmful concentrations for local cells. As BPA-free materials were introduced as being more biocompatible than materials containing BPA, substitution of Bis-GMA with UDMA should be further investigated.

Risk assessment of predicted serum concentrations of bisphenol A in children and adults following treatment with dental composite restoratives, dental sealants, or orthodontic adhesives using physiologically based pharmacokinetic modeling.

Bisphenol A (BPA) is a chemical used to manufacture bisphenol A glycidyl methacrylate (BisGMA). BisGMA has been used for decades in dental composite restoratives, sealants, and adhesives. Based on published studies, exposure to low concentrations of BPA are possible from dental and orthodontic devices. The serum BPA concentrations arising from such devices and oral doses were predicted using a PBPK model in children and adult females based on 1) published extraction data for cured and uncured 3M ESPE Filtek Supreme Ultra Flowable, 3M ESPE Filtek Bulk Fill Restorative, and 3M ESPE Clinpro Sealant and 2) published 20% ethanol/water and water rinsate data following orthodontic application with 3M ESPE Transbond MIP Primer and 3M ESPE Transbond XT Adhesive. Predicted oral exposure to BPA arising from these dental and orthodontic devices is low (median <10 ng/treatment) and predicted serum BPA concentrations were also low (<10-4 nM). Even the maximum predicted exposure in this study (533.2 ng/treatment) yields a margin of exposure of 7.5 relative to the EFSA t-TDI (4 µg/kg-day) and is only 2.8% of the daily BPA exposure for the US population in a 58-kg woman (15,660 ng/day). Therefore, the exposure to BPA arising from the 3M ESPE dental and orthodontic devices evaluated in this study is negligible relative to daily BPA exposure in the general population and these potential BPA sources do not constitute a risk to patients.

[Role of LncRNA CASC11 in the malignant transformation of 16HBE cells induced by glycidyl methacrylate].

OBJECTIVE: To investigate the effect of trending up-regulation LncRNA CASC11 which is differentially expressed during the malignant transformation of human bronchial epithelial cells(16 HBE) induced by glycidyl methacrylate(GMA). METHODS: After 16 HBE cells were repeatedly exposed to low concentration GMA(8 µg/mL), the 10 th, 20 th and 30 th passage cells of the GMA group and the DMSO solvent control group were collected. High throughput LncRNA microarray were used to screen the differentially expressed LncRNAs at different stages. Short Time-series Expression Miner and bioinformatics tool RPISeq were used to screen and predict the potential targets of specific LncRNA. Real-time fluorescent quantitative PCR(qPCR) and Western blot were used to detect the relative expression of specific LncRNA and the content of its target protein respectively. RESULTS: The specific differential expression of LncRNA CASC11 in the process of GMA-induced malignant transformation of 16 HBE cells showed a trend of up-regulation. Compared with the control cells in the same period, the P10, P20 and P30 generation cells were down-regulated by 1.64 times, up-regulated by 2.01 times, and up-regulated by 2.66 times, respectively. Western blot showed that the levels of cyclin-dependent kinase 1(CDK1), cyclinB1 and cyclinB2 in P10, P20 and P30 cells after exposure were lower than those in DMSO control group during the same period, which was consistent with the microarray results. CONCLUSION: The differential expression of LncRNA CASC11 in the process of GMA-induced 16 HBE cell malignant transformation was up-regulated trendingly. It is speculated that it may block or delay cell cycle progression by inhibiting CDK1.

3D Hybrid Nanofiber Aerogels Combining with Nanoparticles Made of a Biocleavable and Targeting Polycation and MiR-26a for Bone Repair.

The healing of large bone defects represents a clinical challenge, often requiring some form of grafting. Three-dimensional (3D) nanofiber aerogels could be a promising bone graft due to their biomimetic morphology and controlled porous structures and composition. miR-26a has been reported to induce the differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) and facilitate bone formation. Introducing miR-26a with a suitable polymeric vector targeting BMSCs could improve and enhance the functions of 3D nanofiber aerogels for bone regeneration. Herein, we first developed the comb-shaped polycation (HA-SS-PGEA) carrying a targeting component, biocleavable groups and short ethanolamine (EA)-decorated poly(glycidyl methacrylate) (PGMA) (abbreviated as PGEA) arms as miR-26a delivery vector. We then assessed the cytotoxicity and transfection efficiency of this polycation and cellular response to miR-26a-incorporated nanoparticles (NPs) in vitro. HA-SS-PGEA exhibited a stronger ability to transport miR-26a and exert its functions than the gold standard polyethyleneimine (PEI) and low-molecular-weight linear PGEA. We finally examined the efficacy of HA-SS-PGEA/miR-26a NPs loaded 3D hybrid nanofiber aerogels showing a positive effect on the cranial bone defect healing. Together, the combination of 3D nanofiber aerogels and functional NPs consisting of a biodegradable and targeting polycation and therapeutic miRNA could be a promising approach for bone regeneration.

Enhanced biochemical characteristics of ß-glucosidase via adsorption and cross-linked enzyme aggregate for rapid cellobiose hydrolysis.

With proper design, immobilization can be useful tool to improve the stability of enzymes, and in certain cases even their activity, selectivity, productivity and economic viability. An immobilized ß-glucosidase (BGL, EC 3.2.1.21) through matrix adsorption and cross-linked enzyme aggregate (ad-CLEA) technology is presented in this work. After adsorption and precipitation, BGL was immobilized to poly(glycidyl methacrylate-co-ethylenedimethacrylate) (PGMA/EDMA) microparticles using glutaraldehyde as the cross-linker. Immobilized BGL exhibits lower apparent Km but much higher Vmax than that of the soluble enzyme, suggesting greater enzyme-substrate affinity and rapid velocity. Besides, ad-CLEA-BGL presents better thermostability retaining activity nearly 70% for 3 h and approximately 50% for 5 h at 70 °C, high operational reusability remaining more than 90% activity after nine uses and excellent storage stability holding about 95% activity after 45 days. Furthermore, the cellobiose is completely hydrolyzed within 1 h with ad-CLEA-BGL, which is significantly more efficient than soluble enzyme (about 4 h). Therefore, BGL was successfully immobilized on PGMA/EDMA microparticles with an ad-CLEA technology and the immobilization greatly enhances the biochemical characteristics. This work indicates promising application for ad-CLEA-BGL in utilizing agricultural remnants, bio-converting cellobiose to fermentable reducing sugar and ethanol production.

Toxicological alert: Exposure to glycidyl methacrylate and cancer risk.

Glycidyl methacrylate (GMA; CAS no. 106-91-2) is a chemical monomer used in the manufacture of dental resins, can coatings and polymers. GMA has demonstrated toxicity to the ocular, digestive, respiratory and dermal systems. Human exposure occurs mainly in the workplace, but it can also happen through food. Although there were no available data on carcinogenicity of GMA, carcinogenic potential in the nasal cavity is highly expected. Further studies are needed to assess GMA exposure in humans. This study provides an alert of GMA human exposure and its genotoxic and carcinogenic potential.

[Role of LINC00310 in the glycidyl methacrylate-induced malignant transformation of human bronchial epithelial cell].

OBJECTIVE: To investigate the expression and biological significance of LINC00310 in the malignant transformation of human bronchial epithelial cells(16 HBE) induced by glycidyl methacrylate(GMA). METHODS: The 16 HBE cells recovered successfully used 1 µg/mL dimethyl sulfoxide(DMSO) as the solvent control group, and the final concentration was 8 µg/mL GMA as the treatment group, and were subcultured after repeated exposure 3 times for 72 hours each time. The 10 th, 20 th and 30 th generation cells of the GMA treatment group and corresponding DMSO control group were collected. The LncRNA microarrays was used to analyze the expression changes of LINC00310 in different periods, and the target gene and function prediction was performed by NCBI and cBioPortal bioinformatics database, and real-time quantification PCR(qPCR) was used to detect the relative expression levels of LINC00310 and predicted target genes. RESULTS: The result of the microarray showed that LINC00310 in the GMA-treated group was down-regulated by 2. 02-fold, up-regulated by 6. 17-fold, and up-regulated by 2. 03-fold in the pre-transformation, mid-term, and late, respectively. The result of qPCR confirmed that the expression of LINC00310 relative expression level of 10 th, 20 th and 30 th generation cells was consistent with the microarray result, which were down-regulated by 2. 76-fold, up-regulated by 2. 68-fold, and up-regulated by 3. 09-fold. Consistently, the relative expression of the target gene C-Myc was statistically significant in 20 th and 30 th generation cells. CONCLUSION: LINC00310 induced low expression in the early stage of malignant transformation of 16 HBE cells induced by GMA, and was highly expressed in the middle and late stages. It indicated that LINC00310 may play a cancer-promoting role in the process of cell malignant transformation through C-Myc.

Smart Delivery Systems Based on Poly(glycidyl methacrylate)s-Coated Organic/Inorganic Core-Shell Nanohybrids.

Smart delivery systems have gained momentum over the last few decades due to their potential to realize enhanced therapeutic efficacy. Poly(glycidyl methacrylate)s (PGMAs), which spring up like mushrooms, have drawn great attention in the theranostics field, especially in multifunctional theranostic systems. The marriage of PGMAs with functional inorganic cores is expected to integrate diagnosis (e.g., fluorescence, X-ray computed tomography, magnetic resonance, photoacoustic and upconversion luminescence imaging), treatment, or multimodal synergistic therapies (e.g., chemotherapy, gene therapy, photothermal therapy) in one pot for personalized medicine. In this review, recent progress in various PGMA-coated nanohybrids based on the type of integrated inorganic nanoparticle, including silica nanoparticles, magnetic nanoparticles, quantum dots, gold nanoparticles, gold nanorods, metal-organic frameworks, cellulose nanocrystals, and their core-shell nanostructures is systematically reviewed. Future work in this field is anticipated to be devoted to developing efficient real-time-imaging-guided multimodal synergistic therapies.

Development of ICAR ATRP-Based Polymerization-Induced Self-Assembly and Its Application in the Preparation of Organic-Inorganic Nanoparticles.

The functionalization and application of nano-objects generated using a polymerization induced self-assembly (PISA) procedure is becoming a focus in recent years. In this contribution, using ethanol as solvent, poly(oligo(ethylene oxide) methyl ether methacrylate) (POEOMA) as macro-initiator/stabilizer, and 2-(perfluorohexyl)ethyl methacrylate (PFHEMA) and glycidyl methacrylate (GMA) as comonomers, the initiators for continuous activator regeneration atom transfer radical polymerization (ICAR ATRP)-based PISA is realized. The lower GMA content system tends to form spheres with large diameters and heavy contrast, while the lower PFHEMA content system tends to form the spheres or short worms with small diameters. However, the system with further increased GMA content results in the failed ICAR ATRP PISA procedure with the formation of precipitates by the cross-linking reaction between pendant epoxy groups. Furthermore, using the efficient reaction between the epoxy group on GMA and thiol group on mercapto-succinic acid agent, the carboxyl groups can be introduced into the inner cavity of the nano-objects and used for incorporation with the Fe2+ and Fe3+ ions, and the organic-inorganic nanoparticles Fe3 O4 @POEOMA are finally prepared in the presence of a reductant.

In Situ Crosslinking of Nanoparticles in Polymerization-Induced Self-Assembly via ARGET ATRP of Glycidyl Methacrylate.

Polymerization-induced self-assembly (PISA) and in situ crosslinking of the formed nanoparticles are successfully realized by activators regenerated by electron-transfer atom transfer radical polymerization (ARGET ATRP) of glycidyl methacrylate (GMA) or a mixture of GMA/benzyl methacrylate (BnMA) monomers in ethanol. Poly(oligo(ethylene oxide) methyl ether methacrylate) was employed as macroinitiator/stabilizer, and a cupric bromide/tris(pyridin-2-ylmethyl)amine complex as catalyst. Tin (2-ethylhexanoate) was used as reducing agent for ARGET ATRP, and simultaneously acted as a catalyst for ring-opening polymerization of oxirane ring in GMA. The kinetics shows that the double bond in GMA was completely polymerized in 4.0 h, while only a 33% conversion of oxirane ring in GMA was reached at 117.0 h. Such a large difference would guarantee a smooth PISA and a subsequent in situ crosslinking of formed nanoparticles. The transmission electron microscopy and dynamic light scattering show spherical nanoparticles formed. With a feed molar ratio [BnMA]0 /[GMA]0 = 150/50, 100/100, and 50/150, the nanoparticles formed in ethanol can dissociate or swell in toluene. When pure GMA was used, the solid nanoparticles were observed in toluene or ethanol. The ARGET ATRP provides an efficient strategy to stabilize the nanoparticles formed in the PISA of GMA-containing system.

Evaluation of the enantioselectivity of capillary electrokinetic chromatography using ethanediamine-bonded poly (glycidyl methacrylate) microspheres as the pseudostationary phases.

In this work, a new capillary electrokinetic chromatography (EKC) approach using ethanediamine-bonded poly (glycidyl methacrylate) (Ami-PGMA) microspheres as pseudostationary phases (PSPs) for enantioseparation with a polysaccharide, chondroitin sulfate E (CSE), as the chiral selector. The CSE@Ami-PGMA EKC system was applied to enantioseparate basic drugs, and distinct improved separations of tested enantiomers were obtained while comparing with the single CSE system (the resolution increased from 0.41 to 1.26 for nefopam, from 1.24 to 2.15 for laudanosine, and from 0.92 to 2.36 for amlodipine). The Ami-PGMA microspheres were fully characterized by scanning electron microscopy (SEM) and Fourier Transform Infrared (FT-IR) spectroscopy, and the results showed Ami-PGMA microspheres were uniform and spherical in size (1 µm). Several principal parameters were systematically investigated, and the optimal chiral separations were obtained with Tris/H3 PO4 (20 mM, pH 2.4, and 3.4 for NEF) containing 2.5% (w/v) CSE and 20-µg Ami-PGMA microspheres in 20°C. Subsequently, the concentrations of Ami-PGMA microspheres and CSE were proved to be the dominant factors for the separation in the CSE@Ami-PGMA EKC system by Statistical Product and Service Solutions (SPSS).