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Bioconjugation is a powerful protein modification strategy to improve protein properties. Herein, we report mechano-bioconjugation as a novel approach to empower fusion protein therapeutics and demonstrate its utility by a protein heterocatenane (

Herein an injectable self-healing hydrogel via dynamic linkage of an imine bond based on a novel multi-aldehyde polyethylene glycol crosslinker was reported. The biocompatible crosslinker could be synthesized via easy chemistry on a large scale. After cross-linking with glycol chitosan, the self-healing hydrogel could be easily obtained in ∼1 h under mild conditions. The prepared hydrogel showed satisfactory mechanical properties and ideal biocompatibility and was successfully used in an in vivo mouse model as a drug carrier just like a “Trojan Horse”. It could deliver a highly concentrated anti-tumor drug (DOX) to the desired position for sustainable controlled release at a safe level. Compared with intravenous or intratumoral injection, the hydrogel drug carrier achieves an admirable therapeutic effect and collectively prevents the recurrence of colon cancer during the whole treatment process. Due to its excellent biocompatibility and good operability, this injectable self-healing hydrogel might be a promising drug carrier for surgical adjuvant treatment and other medical applications. This strategy may provide more insights for the design, study and application of new biomaterials.

The 000A2Π1/2−X2Σ+, 110A2Π1/2−X2Σ+, and 101A2Π1/2−X2Σ+ bands of an internally cold molecular beam sample of ytterbium monohydroxide, YbOH, have been recorded at the near natural linewidth limit and analyzed to determine the fine structure parameters. Numerous lines in the 000A2Π1/2−X2Σ+ band associated with the lowest rotational levels were recorded in the presence of a static electric field and analyzed to determine the magnitude of the molecular frame permanent electric dipole moment, |μel|, for the X2Σ+(0,0,0) and A2Π1/2(0,0,0) states of 1.9(2) and 0.43(10) D, respectively. An electrostatic polarizability model is used to predict the μel for the X2Σ+(0,0,0) state. The 000A2Π1/2−X2Σ+ band is recorded in the presence of a weak static magnetic field to observe the electric dipole allowed transitions having ΔJ=−2, which are used to assist in the rotational quantum number assignment and confirm the identity of the excited state. An expression for the A2Π1/2(0,0,0) magnetic g factor is derived and shown to correctly model the observed magnetic tuning. A comparison with YbF is made and implications for the use of YbOH as a venue for symmetry violation measurements are discussed.

We report the multifunctional nanocomposites (NCs) consisting of 19F-moieties grafted Cu7S4–Au nanoparticles (NPs) for negligible background 19F-magnetic resonance imaging (19F-MRI) and computed tomography (CT) imaging guided photothermal therapy. The localized surface plasmon resonance (LSPR) absorption can be reasonably tuned to the in vivo transparent window (800–900 nm) by coupling Au (

The exploration of novel platforms for highly sensitive and selective detection of species of interest is always demanding. Photothermal sensors have emerged as a novel type of probe, particularly for on-site recognition. Many photothermally responsive materials, including inorganic nanomaterials, organic molecules and biomolecules, have been explored in recent decades for their applications as photothermal sensors. In this review, we will summarize several types of photothermally responsive materials and their applications in sensing. Finally, the prospects and challenges for future developments will be discussed.

The doping of radiocontrast agent such as bismuth (Bi) in copper chalcogenide nanocrystals for computed tomography (CT) imaging guided photothermal therapy (PTT) has drawn increasing attention. However, the doping of Bi often suffers from the weak CT signal due to the low Bi doping concentration and deteriorates the PTT efficacy of copper chalcogenides. Here we report a multifunctional nanoprobe by encapsulating both Cu1.94S and Bi2S3 nanocrystals into a biocompatible poly(amino acid) matrix with size of ~85 nm for CT imaging guided PTT. The amount of nanocrystals and the ratio of Cu1.94S-to-Bi2S3 in the multifunctional nanocomposites (NCs) are tunable toward both high photothermal conversion efficiency (~31%) and excellent CT imaging capability (27.8 HU g L−1). These NCs demonstrate excellent effects for photothermal ablation of tumors after intratumoral injection on 4T1 tumor-bearing mice. Our study may provide a facile strategy for the fabrication of multifunctional theranostics towards simultaneous strong CT signal and excellent PTT.

The exploration of feasible, reliable sensors for the selective and sensitive detection of nitroaromatic explosives is a critical issue nowadays as mandated by homeland security concerns. Our endeavor is to develop an instant on-site visual and ultra-sensitive photothermal nanosensor for 2,4,6 -trinitrotoluene (TNT) detection, which could be applied on a broad scale with high selectivity and sensitivity. The fundamental principle of our work is that TNT could effectively induce the aggregation of the cysteamine-stabilized gold nanoparticles (Au NPs) by forming the Meisenheimer complex, which further enhanced the surface plasmon resonance (SPR) properties and the photothermal effects of Au NPs. Other coexisting nitroaromatics have negligible influences on the photothermal responses. By means of the temperature enhancement and photothermal imaging technique, the presence of TNT could be readily recognized and visualized, indicating wide potential applications in analytical sensing.

Patterned micro-nano arrays have shown great potential in the fields of optics, electronics and optoelectronics. In this study, a strategy of interface-induced dewetting assembly based on capillary liquid bridges and SU-8 photoresist templates is proposed for patterning organic molecules and nanoparticles. First, photoresist templates with chemical stability were prepared via a simplified lithography method. Then the interface wettability and the contact angle hysteresis of water droplets on the fluorosilane modified templates were adequately studied and discussed. Subsequently, a sandwich structure, composed of a superhydrophilic target substrate, a hydrophobic high adhesive photoresist template and a growth solution were introduced for the confined space dewetting assembly. The related mechanism was investigated and revealed, with the assistance of in situ observation via a fluorescence microscope. Finally, the patterned arrays of water-soluble organic small molecules and aqueous dispersed nanoparticles were successfully obtained on the target substrates. This method is simple and easy, and the SU-8 photoresist templates possess a series of advantages such as low processing cost, short preparation periods and reusable performance, which endow this strategy with potential for application in molecular functional devices.

The use of fluorescence probes for biomedical imaging has attracted significant attention over recent years owing to their high resolution at cellular level. The probes are available in many formats including small particle size based imaging agents which are considered to be promising candidates, due to their excellent stabilities. Yet, concerns over the potential cytotoxicity effects of inorganic luminescent particles have led to questions about their suitability for imaging applications. Exploration of alternatives inspired us to use organic fluorophores with aggregation-induced emission (AIE), prepared by functionalizing the amine group on tetraphenylethene with 3,5-bis(trifluoromethyl)phenyl isocyanate. The as-synthesized novel AIE fluorophore (TPE-F) display enhanced quantum yield and longer lifetime as compared with its counterparts (4,4′,4″,4-(ethene-1,1,2,2-tetrayl)tetraaniline, TPE-AM). Furthermore, the TPE-F was encapsulated into small-size organic nanoparticles (NPs; dynamic light scattering size, ∼10 nm) with polysuccinimide (PSI). The biocompatibility, excellent stability, bright fluorescence, and selective cell targeting of these NPs enable the as-prepared TPE-F NPs to be suitable for specific fluorescence cell imaging.

Copper sulfide (Cu7S4) nanoparticles coated with an ultra-high payload (~5.0 × 107 fluorine atoms per particle) of fluorinated ligands (oleylamine functionalized 3,5-bis(trifluoromethyl)benzaldehyde, 19FOAm) exhibited a single intense 19F magnetic resonance (MR) signal and efficient near infrared photothermal performance in water medium. In vivo assessment revealed strong 19F MR signals at cancerous lesions and effective inhibition of tumor growth after photothermal treatment, indicating the great potential of these fabricated nanoprobes for simultaneous 19F MR imaging and photothermal therapy.

The real-time fluorescence tracking of gene delivery is very important as it helps to figure out how a vector enters a cell and also to follow its fate within the cell interior. Lanthanide-doped upconversion nanoparticles (UCNPs) have shown great potential in biomedical applications in virtue of their unique optical and biological properties. Herein, we report a simple and versatile strategy to fabricate a multifunctional nanocapsule for effective gene delivery and real-time luminescence tracking. The hydrophobic UCNPs were modified by positively charged amphiphilic polymer together with polyethylene glycol-poly(lactic-co-glycolic acid) (PEG–PLGA) polymer, affording biocompatible nanocapsules with high gene loading capacity and good stability. Red UC luminescence of UCNPs are able to track the delivery of nanocapsules in cells without background fluorescence interference, in the meantime, the green fluorescence of green fluorescence protein (GFP) expressed by the pDNA could subtly monitor the gene transfection efficacy. The results demonstrated that our nanocapsule has ideal biocompatibility, satisfactory gene loading capacity and great bioimaging ability, which is promising for imaging guided cell therapy and gene engineering.

Drug delivery systems (DDSs) have been getting more and more attention in the field of cancer therapy with the development of nanotechnology. But remote and noninvasive controlled drug release for improving treatment efficacy and reducing side effects faces great challenge. We report a kind of “smart” nanocomposites (NCs) that is sensitive to the surrounding temperature by grafting a layer of thermo-sensitive polymer, poly( N -isopropylacrylamide) (pNIPAm), on the surface of single Cu7S4 nanoparticle (NP) via atom-transfer radical polymerization (ATRP). These NCs demonstrate a photothermal conversion efficiency of 25.4% under 808-nm near infrared (NIR) light irradiation and a drug loading content of 19.4% (drug/total NCs, w / w ) with a lower critical solution temperature (LCST) of ~38°C. At normal physiological temperature (37°C), only 10.8% of the loaded doxorubicin (DOX) was released at physiological pH value (pH 7.4) within 10 h. In the presence of 808-nm irradiation, due to the temperature increment as a result of photothermal effects, DOX was rapidly released.

In this study, we report a novel and facile autoclave strategy for synthesis of near-infrared (NIR) CuInS2 QDs by employing glutathione (GSH) as capping ligand and stabilizer in aqueous media under 100°C. Various experimental parameters including the ratio of precursors, reaction time, reaction temperature, pH effect and stability have been systematically studied. The QDs were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), and Fourier transform infrared spectroscopy (FT-IR). The as-synthesized NIR QDs exhibited low cytotoxicity and maintained excellent cell viability even up to 100 µg/mL. After bioconjugation with Arg-Gly-Asp (RGD) peptide, the obtained CuInS2-RGD QDs have demonstrated high targeting ability with good fluorescence cell imaging performance.

Drug or gene delivery based on nanostructure is promising for treatments of cancers to solve a variety of issues associated with traditional therapeutic agents from poor bioavailability to systemic toxicity. For real-time monitoring of the delivery process, imaging-guided therapy has attracted growing interest in biomedical applications. Luminescent nanostructures serve as an essential tool for illuminating the pathway of drug or gene delivery in biomedical systems. Considering their crucial role in medical applications, we summarize recent progress of luminescent nanostructures as drug- or gene-delivery nanocarriers with simultaneous imaging tracking. We also discuss the design principles and the critical issues faced by multifunctional nanostructure engineering, which might provide guidance for further development in this field.

We report the multifunctional nanocomposites (NCs) consisting of

Rapid, reliable, onsite approaches for detection trace level of trinitrotoluene (TNT) is a pressing necessity for both homeland security and environmental protection. To this end, hydrophilic amine(-NH2) protected Au@Ag nanoparticles (NPs) were developed and fabricated as colorimetric paper sensor for delicate detection of TNT. The as-developed nanoprobe selectively reacts with TNT through classic Meisenheimer complex formation by means of charge transfer process from an electron-rich NH2 group of β-cysteamine to an electron-deficient nitro group on TNT. Due to the absence of this particular interaction of other nitroaromatics, the proposed probe is highly selective for TNT detection with a better linear range (0–20 μg/mL) and limit of detection (LOD) of 0.35 μg/mL. The present work provides a novel and facile strategy to fabricate colorimetric paper sensors with rapid and selective recognition ability for label free analysis of TNT.

The sensitive and selective detection of hydrogen sulfide is of great importance due to its crucial role in pathological and physiological processes. Herein, we report a novel fluorescent platform, AuNCs@GC, for selective detection of hydrogen sulfide in living cells by impregnating the Au nanoclusters (AuNCs) into a biocompatible cationic polymer matrix, glycol-chitosan (GC) nanogel. The confinement effect significantly increased the emissive Au(I) units, resulting in a 6-fold enhancement of quantum yield (from 6.38% to 36.42%). In addition, the prepared positively charged AuNCs@GC nanogel exhibits excellent selectivity and improved sensitivity to aqueous sulfides. Moreover, the as-fabricated AuNCs@GC showed very good biocompatibility and super fluorescence stability across the full pH range and good salt tolerance, which demonstrated excellent adaptability toward intracellular sulfide imaging.

Photodissociation dynamics of carbonyl sulfide (OCS) in the deep ultraviolet region is investigated using a time-sliced ion velocity map imaging technique. The measured total kinetic energy release spectra from the photodissociation of OCS at ∼210 nm shows three dissociation channels to the fragment S(

The photodissociation dynamics of 2‐bromopentane at ∼234 nm has been investigated by utilizing ion‐velocity map imaging technique. The mapped images of Br(2P3/2) (denoted as Br) and Br(2P1/2) (denoted as Br*) fragments were analyzed by means of the speed and angular distributions, respectively. The speed distributions can be fitted with two Gaussian components which are correlated to the two independent reaction paths on the excited potential energy surfaces (PES). The high‐energy component is from the prompt dissociation along the C—Br stretching mode, while the low‐energy one is related to the dissociation from the coupling of the C—Br stretching and bending modes. Relative quantum yield is measured to be 0.892 for Br in the photodissociation of 2‐bromopentane at 234 nm. Combining the anisotropy parameter with the relative quantum yield of Br and Br* fragments, the contributions of the excited 3Q0, 3Q1, and 1Q1 states to the products Br and Br* were derived. The effect of alkyl branching on the mechanism of photodissociation was discussed by comparing the photodissociation processes of four isomers of bromopentane.

Aqueous sulfides are emerging signaling agents implicated in various pathological and physiological processes. The development of sensitive and selective methods for the sensing of these sulfides is therefore very important. Herein, we report that the as-synthesized 1-oxo-1H-phenalene-2,3-dicarbonitrile (OPD) compound provides promising fluorescent properties and unique reactive properties toward aqueous sulfides. It was found that OPD showed high selectivity and sensitivity toward Na2S over thiols and other inorganic sulfur compounds through a sulfide involved reaction which was confirmed by high-resolution mass spectroscopy (HRMS) and nuclear magnetic resonance (NMR) results. The fluorescence intensity increases linearly with sulfide concentration in the range of 1.0-30 μM with a limit of detection of 52 nM. This novel fluorescent probe was further exploited for the fluorescence imaging sensing of aqueous sulfide in HeLa cells.

Photodissociation dynamics of o-bromofluorobenzene in the 234–267 nm range has been experimentally investigated using the DC-slice velocity map imaging technique. It is found that Br(2P3/2) atoms produced from repulsive singlet state surfaces via excitation of one or more 1ππ* excited states dominate the Br photofragments. The quantum yield of spin-orbit excited Br(2P1/2) atoms was found to be only ∼0.02, indicating weak spin-orbit couplings in the low-lying electronic states of o-bromofluorobenzene.

Fluorescence imaging of transduced cells and tissues is valuable in the development of gene vectors and the evaluation of gene therapy efficacy. We report here the simple and rational design of multifunctional nanocomposites (NCs) for simultaneous gene delivery and fluorescence tracking based on ZnS:Mn(2+) quantum dots (QDs) and positively charged polymer coating. The positively charged imidazole in the as-synthesized amphiphilic copolymer can be used for gene loading via electrostatic interaction. While the introduced poly(ethylene glycol) (PEG) can be used to reduce the binding of plasma proteins to nanovectors and minimize clearance by the reticuloendothelial system after intravenous administration. Most importantly, these multifunctional nanovectors showed much lower cellular toxicity than the commercial polyethylenimine (PEI) transfection vectors. On the basis of the red fluorescence of QDs, we can real-time track the gene delivery in cells, and the transfection efficacy of pDNA encoding enhanced green fluorescence protein (pEGFP) was monitored via the green fluorescence of the GFP expressed by the pDNA delivered into the nuclei. Fluorescence imaging analysis confirmed that the QDs-based nanovectors delivered pDNA into HepG2 cells efficiently. These new insights and capabilities pave a new way toward nanocomposite engineering for fluorescence imaging tracking of gene therapy.

The laser-induced fluorescence excitation spectra of jet-cooled CoO molecules have been recorded in the energy region of 21,800-25,000 cm(-1). Apart from the seven vibronic bands assigned to the known G(4)Φ(9∕2)(υ(')) - X(4)Δ(7∕2)(υ(") = 0) progression [M. Barnes, D. J. Clouthier, P. G. Hajigeorgiou, G. Huang, C. T. Kingston, A. J. Merer, G. F. Metha, J. R. D. Peers, and S. J. Rixon, J. Mol. Spectrosc. 186, 374 (1997)], we observed a new band system assignable to the [22.95](4)Δ(7∕2)(υ(') = 0 - 4) - X(4)Δ(7∕2)(υ(") = 0) progression. Extensive perturbations among these vibronic bands have been revealed by means of reduced energy plots. The new electronically excited (4)Δ state has been determined to be most likely of an electronic configuration (2pπ)(3)(4sσ)(2)(3dδ)(3)(3dπ)(3) based on the charge-transferred promotion model.

In order to weaken the noise of the mechanical system of the high accuracy micro-displacement platform and the noise of the control system, the low pass and notch filters were designed for filtering noises. The more simple method of filter design was adopted in this paper. Namely, the real time data exchange modules between LabVIEW program and DSP chip program were used for testing and analysing the filtering performance of FIR filter. Then the filter parameters were determined and filters were implemented in the DSP chip. The results of experiment showed that the tap number of low pass filter with hamming window should be 100 and that tap number of notch filter with Hamming window should be 121. Thus, a low pass filter with 700 Hz cut-off frequency and a notch filter with 300 Hz centre frequency and 100 Hz bandwidth were implemented in the DSP chip. The signal-to-noise ratio (SNR) of output signal in the system could be improved about 26 dB. The program filters in DSP chip could make reasonable use of system resources. Meanwhile, with the help of LabVIEW program, the program of filter algorithm in the DSP chip was simplified and the development cycle was shortened.

The photodissociation dynamics of carbon dioxide cation, CO2(+), mediated by its different Ã(2)Πu,1/2(υ1,υ2,0) vibronic states has been investigated by means of time-sliced velocity map imaging. Through analysis of the recorded translational energy release spectra of photofragment CO(+), we found that the photodissociation of CO2(+) exhibits drastic change in a rather narrow energy region. A conformational barrier in the CO2(+)(Ã(2)A1) state is suggested to be ∼5600 cm(-1) relative to the CO2(+)(Ã(2)Πu,1/2(0,0,0)) state, in reasonable agreement with previous prediction.