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The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has been an unprecedented public health disaster in human history, and its spike (S) protein is the major target for vaccines and antiviral drug development. Although widespread vaccination has been well established, the viral gene is prone to rapid mutation, resulting in multiple global spread waves. Therefore, specific antivirals are needed urgently, especially those against variants. In this study, the domain of the receptor binding motif (RBM) and fusion peptide (FP) (amino acids [aa] 436 to 829; denoted RBMFP) of the SARS-CoV-2 S protein was expressed as a recombinant RBMFP protein in Escherichia coli and identified as being immunogenic and antigenically active. Then, the RBMFP proteins were used for phage display to screen the novel affibody. After prokaryotic expression and selection, four novel affibody molecules (Z14, Z149, Z171, and Z327) were obtained. Through surface plasmon resonance (SPR) and pseudovirus neutralization assay, we showed that affibody molecules specifically bind to the RBMFP protein with high affinity and neutralize against SARS-CoV-2 pseudovirus infection. Especially, Z14 and Z171 displayed strong neutralizing activities against Delta and Omicron variants. Molecular docking predicted that affibody molecule interaction sites with RBM overlapped with ACE2. Thus, the novel affibody molecules could be further developed as specific neutralization agents against SARS-CoV-2 variants.

The longer the local conjugation in the main chain (–CC–Si–O–CO) is, the more conducive to its multicolor fluorescence.

High-efficiency white light emission has been achieved for tetraphenylethylene-based Eu3+-metallopolymers, which also exhibited great potential for applications in ratiomeric temperature sensing and white light emitting diodes.

The copolymerization between 4-VP-PHI, MMA and the Eu3+-complex results in white light emitting Eu3+-metallopolymer, which not only has a lower detection limit, but also a more remarkable color change compared to 4-VP-PHI for the sensing of Zn2+.

Non-conjugated fluorescent polymers have attracted great attention due to their excellent biocompatibility and environmental friendliness. However, it remains a huge challenge to obtain a polymer with high fluorescence quantum yield (QY) and multicolor emission simultaneously. Herein, we reported three kinds of nonaromatic hyperbranched polyborates (P1-P3) with multicolor emission, surprisingly, P2 also exhibits an unanticipated high QY (54.1 %). The natural bond orbital (NBO) analysis and density functional theory (DFT) calculation results revealed that the synergistic effect of rigid BO

SARS-CoV-2 has spread worldwide causing more than 400 million people with virus infections since early 2020. Currently, the existing vaccines targeting the spike glycoprotein (S protein) of SARS-CoV-2 are facing great challenge from the infection of SARS-CoV-2 virus and its multiple S protein variants. Thus, we need to develop a new generation of vaccines to prevent infection of the SARS-CoV-2 variants. Compared with the S protein, the nucleocapsid protein (N protein) of SARS-CoV-2 is more conservative and less mutations, which also plays a vital role in viral infection. Therefore, the N protein may have the great potential for developing new vaccines.The N protein of SARS-CoV-2 was recombinantly expressed and purified in Escherichia coli. Western Blot and ELISA assays were used to demonstrate the immunoreactivity of the recombinant N protein with the serum of 22 COVID-19 patients. We investigated further the response of the specific serum antibodies and cytokine production in BALB/c mice immunized with recombinant N protein by Western Blot and ELISA.The N protein had good immunoreactivity and the production of IgG antibody against N protein in COVID-19 patients was tightly correlated with disease severity. Furthermore, the N protein was used to immunize BALB/c mice to have elicited strong immune responses. Not only high levels of IgG antibody, but also cytokine-IFN-γ were produced in the N protein-immunized mice. Importantly, the N protein immunization induced a high level of IgM antibody produced in the mice.SARS-CoV-2 N protein shows a great big bundle of potentiality for developing a new generation of vaccines in fighting infection of SARS-CoV-2 and its variants.

Using conventional fac-[Ir(C^N)3]-homoleptic or [Ir(C^N)2(L^X)]-bis-heteroleptic iridium(III)-complexes with NIR-phosphorescence (NIR = near infrared) as dopants, the realization of reliable NIR-OLEDs/PLEDs (organic/polymer light-emitting diodes) with high performance remains a real challenge. In this study, taking Hqibt (1-(benzo[b]-thiophen-2-yl)-isoquinoline) as the HC^N1 ligand, Hppy (phenyl-4-yl)pyridine) as the HC^N2 ligand and Br-Hpic (5-Br-picolinic acid) or Hpic (picolinic acid) as the N^O-ancillary, two novel C1-symmetric [Ir(C^N1)(C^N2)(N^O)]-tris-heteroleptic iridium(III)-complexes [Ir(iqbt)(ppy)(pic)] (1) and [Ir(iqbt)(ppy)(Br-pic)] (2) are molecularly designed, respectively, where large TDM (transition dipole moment) and strengthened 3MLCT (metal-to-ligand charge transfer) effects are established to afford their good NIR-phosphorescent efficiency (ΦPL = 0.27 for 1 (λem = 698 nm); 0.21 for 2 (λem = 696 nm)). Moreover, in their doped EMLs (emitting layers), a preferentially horizontal orientation of the TDMs is promoted, due to which, the NIR-PLEDs-1–2 exhibit an attractively high efficiency (ηmaxEQE = 3.1–4.7%; λem = 698 nm) as well as an almost negligible (

Despite the cost-effective and large-area scalable advantages of NIR-PLEDs based on iridium(III)-complex-doped polymers, the intrinsic phase-separation issue leading to inferior device performance is difficult to address. In this study, taking the vinyl-functionalized [Ir(iqbt)2(vb-ppy)] (Hqibt = 1-(benzo[b]-thiophen-2-yl)-isoquinoline; vb-Hppy = 2-(4′-vinylbiphenyl-4-yl)pyridine) as the polymerized complex monomer, two series of Ir(III)-complex-grafted polymers Poly(NVK-co-[Ir(iqbt)2(vb-ppy)]) and Poly((vinyl-PBD)-co-NVK-co-[Ir(iqbt)2(vb-ppy)]) (NVK = N-vinyl-carbazole; vinyl-PBD = 2-(4-(tert-butyl)phenyl)-5-(4′-vinyl-[1,1′-biphenyl]-4-yl)-2,5-dihydro-1,3,4-oxadiazole) are obtained, respectively. Moreover, by using the bipolar Ir(III)-complex-grafted polymer further doped or grafted with an electron-transport unit as the emitting layer (EML), reliable NIR-PLEDs are realized. In particular based on the concurrent covalent-linkages of both the Ir(III)-complex and the vinyl-PBD towards the carrier-balanced NIR-PLED-III, the achievement of an almost negligible (

Despite the domination of conventional [Ir(C^N)2(L^X)]-bis-heteroleptic iridium(III)-complexes with NIR-phosphorescence (NIR = near-infrared) as dopants for reliable NIR-OLEDs/PLEDs (organic/polymer light-emitting diodes), the achievement of high performance remains a real challenge. In this study, taking Hiqbt (1-(benzo[b]-thiophen-2-yl)-isoquinoline) as the C^N ligand and one of the asymmetric Schiff-base ligands with different electronic effects as the N^O-ancillary ligand, three novel C1-symmetric [Ir(C^N)2(N^O)]-bis-heteroleptic iridium(III)-complexes 1–3 were developed. With contributions from the TDM (transition dipole moment) and the emitting dipole orientation induced by the N^O-ancillary electronic effects, the doped NIR-PLEDs-1–3 exhibited attractive high efficiency (ηmaxEQE = 3.3–5.6%; λem = 708–712 nm) apart from the almost negligible (

Hyperbranched polymers hold great promise in nanomedicine for their controlled chemical structures, sizes, multiple terminal groups and enhanced stability than linear amphiphilic polymer assemblies. However, the rational design of hyperbranched polymer-based nanomedicine with low toxic materials, selective cellular uptake, controlled drug release, as well as real-time drug release tracking remains challenging. In this work, a hyperbranched multifunctional prodrug HBPSi-SS-HCPT is constructed basing on the nonconventional aggregation-induced emission (AIE) featured hyperbranched polysiloxanes (HBPSi). The HBPSi is a biocompatible AIE macromolecule devoid of conjugates, showing a high quantum yield of 17.88% and low cytotoxicity. By covalently grafting the anticancer drug, 10-hydroxycamptothecin (HCPT), to the HBPSi through 3,3'-dithiodipropionic acid, HBPSi-SS-HCPT is obtained. The HBPSis demonstrate obvious AIE features and it turned to aggregation-caused quenching (ACQ) after grafting HCPT owing to the FRET behavior between HBPSi and HCPT in HBPSi-SS-HCPT. In addition to on-demand HCPT release in response to changes in environmental pH and glutathione, a series of in vitro and in vivo studies revealed that HBPSi-SS-HCPT exhibits enhanced accumulation in tumor tissues through the enhanced permeation and retention (EPR) effect and preferential cancer cell uptake by charge reversal, thus resulting in apoptotic cell death subsequently. This newly developed multifunctional HBPSi-SS-HCPT prodrug provides a biocompatible strategy for controlled drug delivery, preferential cancer cell uptake, on-demand drug release and enhanced antitumor efficacy.

Multicolour emissive nonconventional macromolecular luminogens with aggregation-induced emission have drawn great attention due to their potential application in a wide range of areas. However, the exploration of efficient synthetic strategies and emission mechanisms still remains a challenge. Herein, we report a facile route to the synthesis of hyperbranched polysiloxane (P1) with adjacent –CO and –CC groups. Surprisingly, it not only showed blue emission under white light excitation, but also exhibited multicolour luminescence under different excitation wavelengths. Especially, multiple through-space conjugation rings can be found between the first generation P1 molecules via DFT calculation; based on its remarkable luminescence properties, we proposed a new luminescence mechanism namely “multiring-induced multicolour emission” (MIE). In addition, the stimuli-responsive behaviour of P1 as well as its application in data encryption based on the quenching effect of Fe3+ was studied. This work provides guidance to design and synthesise nonconventional macromolecular AIEgens with multicolour luminescence.

Fluorescent carbon dots (CDs) are drawing increasing attention due to their excellent properties, however, CDs usually show excitation-dependent emission property. Herein, we prepared a series of multi-excitation and single color emission carbon dots doped with nitrogen and silicon (SiN-CDs) by one-pot hydrothermal method from a hyperbranched polysiloxane. Interestingly, the synthesized SiN-CDs have three excitation bands at around 240, 300 and 360 nm, and only one emission band at around 440 nm. Meanwhile, SiN-CDs emit single color light in a wide excitation range and different concentrations. Structural and optical property characterizations show that the multi-excitation and single color emission property of SiN-CDs is caused by the cooperation of the sp2 carbon core with the abundant fluorescent groups on the surface. In particular, SiN-CDs have multiple functions, not only can be internalized into live cells with obvious accumulation in cell nuclei, but also possess high selectivity, sensitivity and anti-interference ability in detecting of Fe3+.

Luminescent polymers without traditional aromatic groups have attracted great attention due to their excellent biocompatibility and promising applications. Understanding of the luminescence mechanism of such polymers, however, is still in its infancy. To further reveal the fluorescence mechanism in depth, two kinds of oligomeric siloxanes were skillfully elaborated and fabricated via a convenient and facile one-pot transesterification polycondensation reaction under catalyst-free conditions. Intriguingly, oligomeric siloxanes bearing nonconventional chromophores show bright blue fluorescence under 365 nm UV lamp illumination. Our preliminary results demonstrate that oxygen clusters, namely, clustering-triggered emission (CTE), can well explain the inherent fluorescence of oligomeric siloxanes. Moreover, intermolecular hydrogen bonds are conducive to the aggregation of the molecular chains. Then, these bonds will facilitate the formation of oxygen clusters, which produce electron cloud overlap to form the unusual chromophores. In addition, the results suggest that the fluorescence intensity of oligomeric siloxanes enhances with increasing concentration. Furthermore, excitation-dependent emission behavior is observed when varying the excitation wavelength of oligomeric siloxanes. It is also found that the luminescence of oligomeric siloxanes could be effectively tuned by the solvent and metal ions. Oligomeric siloxanes bearing unconventional fluorescence units, i.e., oxygen, amino, and hydroxyl functionalities, show the intrinsic blue fluorescence that results from oxygen clusters, namely, the CTE mechanism. In addition, intermolecular hydrogen bonds are conducive to the aggregation of the molecular chains and the formation of oxygen clusters.

Through the replacement of the β-diketonate Hbtfa (Hbtfa=4,4,4-trifluoro-3-hydroxy-1-phenylbutanone) with the bis-β-diketonate ligand H2btp (H2btp=1,3-bis(4,4,4-trifluoro-1,3-dioxobutyl)benzene), structure converts from mononuclear [Ir(iqbt)2(btfa)] (1) (Hiqbt=1-(benzo[b]-thiophen-2-yl)-isoquinoline) to asymmetric dinuclear [(iqbt)2Ir-(btp)-Ir(iqbt)2] (2) framework toward larger molecule conjugation. Upon a significant bathochromic shift into the restrictive near-infrared (NIR) regime (λem=722 nm for complex 2 and 698 nm for complex 1), the superior phosphorescence (Φem=0.15 and τ = 1.27 μs) of complex 2 to that (Φem=0.08 and τ = 0.78 μs) of complex 1 is also approached. Moreover, within the realization of their solution-processed NIR polymer light-emitting diodes (NIR-PLEDs-I-II), complex-2-doped NIR-PLED-II in the presence of TmPyPB-assisted (TmPyPB=1,3,5-tri[(3-pyridyl)-phen-3-yl]benzene) carrier balance, exhibits the attractive electroluminescent (EL) performance with both ηEQEmax= 3.11% and almost negligible efficiency-roll-off.

Unorthodox luminogenic polymers without aromatic luminogens have attracted great interest in recent years; however, the low fluorescence efficiency is still a big drawback. In this paper, we synthe...

Through free-radical copolymerization of the Yb3+-centered near-infrared (NIR) luminescent complex monomer [Zn(L1)(4-vinyl-Py)Yb(L2)3] (2) (H2L1 = N,N’-bis(salicylidene)−1,2-diamine; 4-vinyl-Py = 4-vinyl-pyridine and HL2 = (Z)−3-methyl-1-phenyl-4-(2,2,2-trifluoro-1-hydroxyethylidene)−1H-pyrazol-5(4H)-one) with NVK (N-vinylcarbazole), the obtained [Zn(L1)(4-vinyl-Py)Yb(L2)3]-grafted polymer Poly(NVK-co-2) with additional PVK (Poly(N-vinylcarbazole)) to Yb3+ ion Foster energy transfer is used as the emitting material of polymer light-emitting diode (PLED), exhibiting the Yb3+-centered NIR outputs at 980 nm with a maximum efficiency of 0.049% (at 5.62 mA/cm2) and a maximum irradiance of 78.68 μW/cm2 (at 16 V), respectively. This superior performance to those of previously reported organo-Yb3+-doped polymer systems, together with the characters of low turn-on voltage of 7 V and weak efficiency-roll-off (0.049–0.031% upon 5.62–233.6 mA/cm2), indicates that organo-Yb3+-grafted polymer is an effective strategy to develop PLEDs with the wavelength extended to 980 nm.

We have previously reported that bovine papillomavirus type 1 (BPV-1) DNA can replicate its genome and produce infectious virus-like particles in short term virion-infected S. cerevisiae (budding yeast) cultures (Zhao and Frazer 2002, Journal of Virology, 76:3359–64 and 76:12265–73). Here, we report the episomal replications of BPV-1 DNA in long term virion-infected S. cerevisiae culture up to 108 days. Episomal replications of the BPV-1 DNA could be divided into three patterns at three stages, early active replication (day 3–16), middle weak replication (day 23–34/45) and late stable replication (day 45–82). Two-dimensional gel electrophoresis analysis and Southern blot hybridization have revealed further that multiple replication intermediates of BPV-1 DNA including linear form, stranded DNA, monomers and higher oligomers were detected in the virion-infected yeast cells over the time course. Higher oligomers shown as covalently closed circular DNAs (cccDNAs) are the most important replication intermediates that serve as the main nuclear transcription template for producing all viral RNAs in the viral life cycle. In this study, the cccDNAs were generated at the early active replication stage with the highest frequencies and then at late stable replication, but they appeared to be suppressed at the middle weak replication. Our data provided a novel insight that BPV-1 genomic DNA could replicate episomally for the long period and produce the key replication intermediates cccDNAs in S. cerevisiae system.

We have previously reported that bovine papillomavirus type 1 (BPV1) can replicate its genome and produces infectious virus-like particles in short-term BPV1 virion-infected Sacharomyces cerevisiae (Zhao and Frazer, 2002). Here, we report viral RNA transcription and L1 capsid protein expression in long-term BPV1 virion-infected S. cerevisiae culture. Northern blot hybridization showed that viral RNA was detected in long-term BPV1-infected S. cerevisiae cultures (82-108 days). The levels of the viral RNA transcription varied significantly over the long time period, which showed active transcription at an early stage (Day 3 to Day 16), weak transcription at a middle stage (Day 23 to Day 45) and stable transcription at the late stage of culture (Day 55 to Day 82/85/95). Three major BPV1 transcripts of 4.3, 2.6 and 1.8 Kb were identified, with 4.3 Kb a minor transcript and the 1.8 Kb the most prominent transcript compared with the 2.6 Kb species. Immunoblotting showed that L1 capsid protein was expressed, with its variable amounts corresponding to the levels of RNA transcription over the time period. 35S-methionine/cysteine labeling and immunoprecipitation proved that the detected L1 protein was newly synthesized in BPV1-infected S. cerevisiae cultures. 33.3-54.2% of the cell colonies expressed L1 protein. Thus, the S. cerevisiae system, as a promising model, may be used not only for the study of virus like particle formation of BPV1 in vitro, but also for further functional analysis of individual viral genes in BPV1 life cycle. Keywords: BPV1; viral RNA transcription; expression of L1 capsid protein; virion-infected Saccharomyces cerevisiae.

Hyperbranched polysiloxane (HBPSi) is attracting increasing attention due to its intrinsic fluorescence and good biocompatibility. However, it is very challenging to explore its biological applications because of the low fluorescence intensity and quantum yield. Herein, we introduced rigid β-cyclodextrin to the end of flexible polysiloxane chain to synthesize a novel fluorescent polymer (HBPSi-CD) and explore its biological applications. Results showed that the fluorescence intensity and quantum yield of HBPSi-CD, compared with HBPSi, were significantly enhanced. Theoretical calculations and transmission electron microscopy demonstrated that the synergy effect of intra/intermolecular hydrogen bonds and hydrophobic effect promoted the formation of large supramolecular self-assemblies and space electron delocalization systems, leading to intense fluorescence. Notably, the biocompatible HBPSi-CD not only lighted up mouse fibroblast cells, but also possessed high ibuprofen loading capacity (160 mg g-1) and superior pH-responsive drug release performance. This work promoted the development of biological applications of HBPSi.

Two series of OAc–-dependent unique homoleptic nonanuclear [Ln9(L1)3(HL1)2(μ3-OH)4(OAc)10] (1–7) and hexanuclear {[Ln6(L2)4(HL2)(μ3-OH)(OAc)2(H2O)2]·(OAc)} (8–14) are obtained from the self-assembly of the partially deprotonated OH-H2Salen ligand H3L1 (N,N′-bis(salicylidene)(propylene-2-ol)-1,3-diamine) or OH-MeO-H2Salen ligand H3L2 (N,N′-bis(3-methoxysalicylidene)(propylene-2-ol)-1,3-diamine) with Ln(OAc)3 (Ln = La, Eu, Tb, Gd, Nd, Yb, or Er), respectively. The result of their photophysical properties shows that the sensitization for single-component near-white-light of complex 2, efficient Eu3+-centered red-light (ΦLEu = 13.4%) of complex 9, or or Tb3+-centered yellowish-green-light (ΦLTb = 8.1% and 21.3%) of complexes 3 and 10, and Nd3+- or Yb3+-centered NIR luminescence (η = ΦLLn/ΦLnLn = 67–75% and 76–85%) for complexes 5–6 and 12–13, arose from the ligands’ 3π–π* excited state, due to effective intramolecular energy transfer and multiple Ln3+-to-Ln3+ electron-communications.

Plastic combustion has adverse impacts on air quality and human health. In this work, a novel non-aromatic Si, P, N-containing hyperbranched flame retardant (HPNSi) was synthesized and proposed to epoxy resin. The modified epoxy exhibits not only reduced fire hazards and less smoke production in favor of eco-friendly, but also remarkable mechanical properties and lower curing temperature for facile processability. With 6 wt% incorporation, the peak heat release and total smoke production were reduced by 29.6% and 20.7%, respectively, and the time to ignition (TTI) increased as well as the fire growth rate (FIGRA) dropped off, which is of vital significance for saving lives in a fire. Meanwhile, the impact strength and flexural strength greatly enhanced by 72.9% and 22.0%, while its curing temperature was lower than that of controlled EP system. Interestingly, we also found that the solid carbon particles on the char surface apparently reduced from SEM image. The blending of its unique non-aromatic hyperbranched structure containing Si, P, N with epoxy architecture was responsible for the desirable integrated enhancement. The broad possibilities in the field of flame-retardant plastic with reduced fire hazards and excellent integrated performance enable the novel hyperbranched flame retardant a bright future for application.

Through the single-nodal copolymerization of MMA (methyl methacrylate) and a vinyl-containing complex monomer [Zn(L)(4-vinyl-Py)Nd(NO3)3] (2; H2L = N,N′-bis(3-methoxy-salicylidene)ethylene-1,2-diamine; 4-vinyl-Py = 4-vinyl-pyridine) with the both 1π-π* and 3π-π* sensitizing approach to Nd3 + ion, the Zn2 +-Nd3 +-containing metallopolymer Poly(MMA-co-2) exhibits good physical properties including an attractive Nd3 +-centered NIR sensitization efficiency (ΦLNd = 1.22% and η = ΦLNd/ΦNdNd = 82%).

Based on the quaternary copolymerization of the vinyl-functionalized monomers of a Schiff-base HVBMP (2-(((4-vinylphenyl)imino)methyl)phenol), its boride BF2-VBMP (2,2-difluoro-3-(4-vinylphenyl)-2H-2λ4,3λ4-benzo [e] (Schubert and Kim, 2005; Shao et al., 2019; Wang et al., 2011) [1,3,2]oxazaborinine) and an organo-Eu3+- complex [Eu(TTA)3(4-VP-BPI)] (HTTA = 2-thenoyltrifluoroacetonate; 4-VB-PBI = 1-(4- vinylbenzyl)-2-(pyridin-2-yl)-1H-benzo [d]imidazole)) with MMA (methyl methacrylate), a single-component white-light-emitting ((CIE coordinate (0.320, 0.341), CRI = 95, CCT = 6078 K and Φ = 4.31%; λex = 380 nm) Eu3+-metallopolymer Poly[HVBMP-co-(BF2-VBMP)-co- Eu-co-MMA] (0.5:0.5:1:100) is obtained. Moreover, upon spin-coating of the Eu3+-metallopolymer onto a near-ultraviolet (n-UV) InGaN chip, the n-UV white light-emitting diode (n-UV-WLED) characteristic of the high-quality white-light (CIE coordinate (0.337, 0.367), CRI = 83 and CCT = 5318 K) with the luminance of 2880 cd/m2 at the applied voltage of 4 V, is successfully developed. This result shows that single-component Eu3+-metallopolymer capable of the BF2-chelation-assisted trichromatic white-light modulation, endows a promising opportunity to the potential n-UV-WLEDs.

Despite concerted efforts to cyclometalated Ir(III)-complexes towards reliable vacuum-deposited/solution-processed deep-red organic/polymer light-emitting diodes (OLEDs/PLEDs), the realization of their all-solution-processed ones with desirable lower-cost, is challenging and rarely reported. In this work, using the Hdpqx (2,3-diphenylquinoxaline) as the C^N main ligand and the asymmetric π-donor HL1/HL2 (HL1 = (2-(4,5-diphenyl-1H-imidazol-2-yl)phenol); HL2 = 2-(1,4,5-triphenyl-1H-imidazol-2-yl)phenol)) as the N^OH ancillary ligand, two C1-[Ir(C^N)2(N^O)]-heteroleptic Ir(III)-complexes [Ir(dpqx)2(L1)] (1) and [Ir(dpqx)2(L2)] (2) with efficient deep-red phosphorescence (λem = 662–665 nm and ΦPL = 0.34–0.42) were molecularly designed. Meanwhile, based on the all-solution-processed fabrication, their reliable all-solution-processed deep-red PLEDs with the attractive electroluminescent performance (ηcMax = 0.51–0.58 cd/A, ηpMax = of 0.11–0.13 lm/W and ηEQEMax = 2.08–2.16%; weak (ca. 26–27%) efficiency-roll-offs) were realized.

In this paper, Poly(HVBMP-co-MMA) (1:100) with yellowish-green emission and the Eu3+-metallopolymer Poly(HVBMP-co-Eu-co-MMA) (1:1:100) characteristic of the Eu3+-incorporated reddish-orange emission were synthesized via the copolymerization between MMA (methyl methacrylate), vinyl-functionalized Schiff-base monomer HVBMP (2-(((4-vinylphenyl)imino)methyl)phenol), and/or organo-Eu3+-complex monomer [Eu(TTA)3(4-VB-PBI)] (HTTA = 2-thenoyltrifluoroacetonate; 4-VBPBI = 1-(4-vinylbenzyl)-2- (pyridin-2-yl)-1H-benzo[d]imidazole). Interestingly enough, through the simple BF2-chelation, the yellowish-green emission of Poly(HVBMP-co-MMA) (1:100) can be smoothly tuned to blue from Poly[(BF2-VBMP)-co-MMA) (1:1:100), as well as for Poly(HVBMP-co-Eu-co-MMA) (1:1:100) with reddish-orange emission, dichromatic white-light (ɸ = 2.94%; CCT = 8722 K and CRI = 54) at the CIE coordinate (0.307, 0.247) can be achieved from Poly[(BF2-VBMP)-co-Eu-co-MMA] (1:1:100). The facile synthetic approach combined with the excellent color tuning ability indicating the great potential of BF2-chelation for future application in design and synthesis of multicolor light emitting polymer.

The compressed conformations and degree of coiling of 1,ω-diammonio-oligo(ethylene glycol) (OEG) guests have been determined within the internal space of crystalline pyrene box host capsules. It was observed that the longest OEG chains have the tendency to fold in on themselves inside this confined medium. The phenomenon was observed in solution by NMR spectroscopy, and structural proof has been provided by single-crystal X-ray diffraction. The overall supramolecular spatial arrangement of the “pyrene box” system incorporating OEGs remains relatively unchanged compared with previously reported cages encapsulating alkane chains. However, some structural and dimensional variations/adaptations to accommodate coiled OEG guests of different sizes and shapes can be observed.

Through the ring-opening metathesis polymerization (ROMP) of norbornene (NBE) with each of obtained allyl-containing complex monomers [Zn(L) 2 (Py)Ln(NO 3 ) 3 ] (Ln = La, 1 ; Nd, 2 ; Yb, 3 ; Er, 4 or Gd, 5 ; HL = 4-allyl-2-(1 H -benzo[ d ]imidazol-2-yl)-6-methoxyphenol; Py = pyridine), a series of metallopolymers Poly(NBE- co -[Zn(L) 2 Ln(Py)(NO 3 ) 3 )]) were obtained, respectively. Especially for Poly(NBE- co -2) and Poly(NBE- co -3) , covalently-bonded grafting endows significantly improved physical properties including efficient NIR luminescence ( Φ Nd L = 0.63% and Φ Yb L = 1.43%) in solid state.

By anchoring lanthanide coordination monomers onto a PMMA polymer backbone via a pre-designed vinylbenzyl-substituted NTB-type ligand, we succeeded in the fabrication of homo or hetero Ln-metallopolymers that can emit tunable and designable multicoloured photoluminescence as well as white light emission. Copolymerization results in the fine-tuning of the energy state of the ligand in the metallopolymer compared with that in the coordination monomer, thereby changing the energy transfer efficiency to Eu3+ and Tb3+ centers in opposite ways. And further designing of hetero-lanthanide metallopolymers leads to additional energy transfer between Eu3+ and Tb3+, facilitating the generation of pure white light emission. In general, the facile and controllable synthesis procedure, versatile and reproducible combination of lanthanides, ligands and polymer backbones, and relatively high white light emitting luminous efficiency (>5%) prove this method to be promising in future lighting WPLED applications.

Through the radical copolymerization of MMA (methyl methacrylate) with a vinyl-containing complex monomer {[Yb4(L)2(HL)2(μ3-OH)2(NO3)2]·(NO3)2} (1; H2L = N,N′’-bis-(5-(3′-vinylphenyl)-3-methoxy-salicylidene)cyclohexane-1,2-diamine), the first example of PMMA-supported and Yb4(Salen)4-containing metallopolymer Poly(1-co-MMA) exhibits significantly improved physical properties besides relatively higher NIR quantum yields (ΦYbYb = 1.18% and ΦLYb = 0.86%) than those (ΦYbYb = 1.02–1.04% and ΦLYb = 0.73–0.75%) of complex monomer 1 in solution and 1@PMMA in solid state.

The binding and the encapsulation of the 6-aminohexanoic acid (1) and 11-aminoundecanoic acid (2) are achieved in aqueous solution and in crystalline Pyrene-box cages. Unexpectedly, the amino-guanidinium AG+ and the amino acids 1 or 2 are reacting in aqueous solution in the absence and in the presence of Pyrene-box cages. The formation of an amide bond between a carboxylic acid and the amino-guanidine unit under mild acidic conditions in water without the use a coupling reagent is extremely interesting and unexpected. The resulted adducts AG1 and AG2 show adaptive binding behaviors and compressions.

International audience; The present work shows that encapsulation can be used to promote amide bond formation in water under mild conditions, in the absence of carbodiimide coupling agents.

Polyimide (PI) stands out for excellent mechanical properties, high thermal stability and flexible property, however, the large friction coefficient and wear rate are still big issues which limit its application. In this work, we successfully synthesized a novel POSS-containing polyimide by the copolymerization of diamine polyhedral oligomeric silsesquioxane (POSS-diamine), pyromellitic dianhydride (PMDA) and 4,4′-Oxydianiline (ODA). Subsequently, the POSS-containing polyimide was mixed with self-made graphene-like molybdenum disulfide (MoS2) to fabricate composite coating POSS-PI/MoS2. The tribological properties of POSS-PI/MoS2 are greatly enhanced via the synergistic effects between POSS and graphene-like MoS2. The combination of 10 wt.% POSS-diamine and 12 wt.% graphene-like MoS2 with polyimide leads to 368 % increase of wear life (100 s to 468 s) and 83.3 % decrease of friction coefficient (0.12 to 0.02), especially 15 folds of load carrying capacity (1100 N to 15313 N), compared with pure polyimide. In general, the facile and controllable synthesis procedure, versatile and reproducible combination of POSS-diamine, PMDA and ODA, and relatively high tribological properties of the resulting composite coating, prove this method to be instructive significance for preparing high performance composite coating in future.

Through the ring-opening metathesis polymerization (ROMP) of norbornene (NBE) with each of the obtained allyl-containing complex monomers {[Ln3(L)4Cl4(MeOH)2]·Cl} (Ln = La, 1; Nd, 2; Yb, 3; Er, 4 or Gd, 5; HL = 4-allyl-2-(1H-benzo[d]imidazol-2-yl)-6-methoxyphenol), a series of metallopolymers Poly({[Ln3(L)4Cl4(MeOH)2]·Cl}-co-NBE) were obtained, respectively. Especially for Poly(NBE-co-2) and Poly(NBE-co-3), covalently-bonded grafting endows significantly improved physical properties including efficient NIR luminescence (ΦNdL = 0.58% and ΦYbL = 0.88%) in solid state.

Considering the importance of NIR-dyes especially with the emissive proportion to 100%, in this work, we reported series of [Ir(dpbq)2(O^O)]-heteroleptic Ir3+-complexes 1–4 (Hdpbq = 2,3-diphenylbenzo[g]quinoxaline) with typically NIR-emitting (λem = 780 nm) phosphorescence, featuring the 3LLCT-dominated and the less 3MLCT transitions’ nature. Especially in dependence on the pyrazolonate-O^O ancillary incorporation while irrelevant to the –CF3 electron-withdrawing effect, the complexes 3–4 are more efficient (Φem = 1.9–2.5%) than the β-diketonate-assisted complexes 1–2. This result expectably improved by the following structural optimization, renders [Ir(dpbq)2(O^O)]-heteroleptic Ir3+-complex system a new avenue to typically NIR-emissive emitters.

In this work, for the obtained NIR-emitting dinuclear [(iqbt)2Ir-Ln-Ir(iqbt)2] complexes (n = 1–3, 1–3; Hiqbt = 1-(benzo[b]-thiophen-2-yl)-isoquinoline) with the bridging linkages of three flexible bis-N^O-Schiff-base ligands H2Ln, their obvious aggregation-induced phosphorescent enhancement (AIPE) behaviors in powder-form solid or MeCN–H2O mixture are observed, respectively. Moreover, based on the AIPE-switched NIR phosphorescence (Φem = 0.11 and τ = 0.27 μs) of the diiridium complex 1 without electron-donating substituents in the aggregation state, its solution-processed NIR-PLED is reliably realized, exhibiting the attractive electroluminescent performance with both ηEQEmax = 1.08% and almost negligible efficiency-roll-off.

Multicolored fluorescence stemed from the nonconventional luminescent polymers without aromatic units is an interesting and meaningful property. So far, a few such polymers bearing multicolored fluorescence are reported; its species, however, are relatively little. Herein, we synthesized a kind of novel water-soluble hyperbranched poly(amine ester) (HPAE) via a straightforward transesterification polycondensation reaction using inexpensive and easily available chemicals. Intriguingly, the pure HPAE could emit blue, green and red luminescence when irradiated by different excitation wavelengths. The TEM result shows that the synergy effect of intra-/intermolecular hydrogen bonds and hydrophobic effect could induce the HPAE to self-assemble and form supramolecular HPAE in water. Such supramolecular HPAE further promote to form stronger through-space conjugation, thus which is favourable for the emission. In addition, the significant solvent and pH dependence profiles of luminescence intensity are also observed. In particular, the HPAE can be used to detect metal ions, and there is strong selective quenching in respect of Fe3+. Therefore, the HPAE show a potential probe for Fe3+.