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Blue crest between the wavelength of 460 nm and 480 nm was reported to present melatonin suppression effects, whereas effects of red light on circadian rhythm regulation remain unclear. Spectrum plays an important role in circadian rhythm regulation, yet a lot of researches focused on the correlated color temperature, although a correlated color temperature value corresponds to various possible spectrums. Here, we performed human factor experiments with 3 lamps on 17 participants, comprising 9 males and 8 females. Our results showed that spectrums with high blue intensity tended to cause abnormal regulations of melatonin and cortisol, while the abnormalities were likely to be compensated by the 606-635-nm red light, which was indispensable for the photo-biological effects concerning circadian rhythm regulation. Abnormal circadian rhythm regulation was also found to be influenced by the illuminance, as abnormalities were significant in 500 lux whereas they were likely to disappear in 250 lux, implying the existence of threshold doses to trigger abnormities concerning circadian rhythm regulation. Furthermore, circadian rhythm responses were distinct between males and females. Our work may have implications for the development of light source, as we suggest that lighting source designers should increase the 606-635-nm intensity for bed room luminaires to decrease melatonin suppression effects.

Ligand-targeting specific liposomal probes are increasingly used as imaging and delivery vehicles for in vivo diagnosis. Thereinto, the ligand variety and density profoundly affect the binding behaviors toward the target. The synergetic effect of different ligands could be achieved only when the optimized molecular-recognition configuration occurred. In this study, we construct a dual-peptides-targeting liposomal probe named BTLS that could synergistically bind two different sites of prominin-1, a cancer stem cell marker. At the distance of 11 Å between the two new peptides, ligands could insert into the hollow pocket of prominin-1 and BTLS could achieve the appropriate spatial structure, showing the strong binding affinity in both cellular and in vivo levels. It is indicated that the design of density-optimized peptide-targeted liposomes could be promising to maximize the multifunctional targeting effects on the cancer theranostics.

Herein, we describe a new chiral amorphous metal-organic polyhedra used as the stationary phase for high-resolution gas chromatography (GC). The chiral stationary phase was coated onto a capillary column via a dynamic coating process and investigated for a variety of compounds. The experimental results showed that the chiral stationary phase exhibits good selectivity for linear alkanes, linear alcohols, polycyclic aromatic hydrocarbons, isomers, and chiral compounds. In addition, the column has the advantages of high column efficiency and short analysis time. The present work indicated that amorphous metal-organic polyhedra have great potential for application as a new type of stationary phase for GC.

Combining quantum dots with molecular imprinting techniques, a fluorescent molecularly imprinted membrane (MIM) is prepared by embedding l -cysteine-capped Mn2+-doped ZnS quantum dots (QDs) into molecularly imprinted polymer matrix. This fluorescent MIM is used as biosensor for specific recognition of a target protein (lysozyme). The key point of this approach is that the fluorescent quantum dots embedded into a molecularly imprinted membrane, which enables the optical readout characteristic and high selectivity within a thin hydrogel membrane. When the fluorescent MIM selectively captures the target protein, the electron transfer between the QDs and the target protein will result in the fluorescence quenching of the membrane. And the quenched fluorescence emission intensity was proportional to the concentration of the analytes. The as-prepared membrane was successfully applied to selectively and sensitively detect target proteins without any time-consuming pretreatments. Under optimal conditions, the linear detection of the fluorescence MIM ranged from 1.0 × 10−7 to 1.0 × 10−6 mol L−1 with the detection limit of 10.2 nM. Furthermore, the MIM was applied to determine lysozyme in real samples with recoveries of 93%–103%. Experimental results showed that the fluorescent MIM might serve as a simple and sensitive fluorescent biosensor for detecting target protein in complex biological samples.

Four geminal ionic liquids (GILs), namely, 1,4-bis(1,1′-butyl-3,3′- methylene- imidazolium)-benzene bis[(trifluoromethyl)sulfonyl]imide (BBMIB-NTf2), 1,4- bis(1,1′-butyl-3,3′-methylene-imidazolium)-benzene tetrafluoroborate (BBMIB-BF4), 1,4- bis(1,1′-butyl-3,3′-methylene-imidazolium)-benzene hexafluophosphate (BBMIB-PF6), and 1,4-bis(1,1′-methyl-3,3′-methylene-imidazolium)-benzene bis[(trifluoromethyl) sulfonyl] imide (BMMIB-NTf2), were synthesized. They were statically coated onto the inner walls of fused-silica capillary columns and used as stationary phases for gas chromatography. The evaluation of BBMIB-NTf2, BBMIB-BF4, BBMIB-PF6, and BMMIB-NTf2 as stationary phases is reported here for the first time. These new stationary phases exhibit efficiencies of at least 2.3 × 103 plates per meter. Abraham solvation parameter model was used to evaluate the solvation characteristics. The system constants indicated that the dipolarity/polarizability and the hydrogen-bond basicity play a major role among five mol...

Graphical abstract Schematic 1 Electrochemical determination of human IgG using CuFe2O4 nanospheres molecularly imprinted polymers modified with MoS2@N-GQDs-IL., Highlights • A selective and rapid electrochemical sensing method was developed to determine IgG. • MoS2@N-GQDs-IL with excellent performance was first prepared to modify electrodes. • IgG was successfully determined in the human serum specimens. • This method reveals superior limit of detection and linear concentration range., An advanced molecularly imprinted electrochemical sensor with high sensitivity and selectivity for the detection of Human immunoglobulin G (IgG) was successfully constructed. With acrylamide imprinting systems, surface imprinting on the nanoparticles CuFe2O4 targeted at IgG was employed to prepare molecularly imprinted polymer, which served as recognition element for the electrochemical sensor. Furthermore, the sensor harnessed a molybdenum disulfide (MoS2)@nitrogen doped graphene quantum dots (N-GQDs) with ionic liquid (IL) nanocomposite for signal amplification. Under optimized experimental conditions, the sensor shortened the response time to less than 8 min, and the response was linear at the IgG concentration of 0.1–50 ng·mL−1 with a low detection limit of 0.02 ng·mL−1 (S/N = 3). Our findings suggested that, the sensor exhibited high detectability and long-time stability. The satisfactory results of human serum sample analysis showed that the developed IgG sensor had promising potential clinical applications in detecting IgG content.

Chiral metal-organic cages (MOCs) are a new type of porous materials with unique molecular recognition ability, which have received research attention as a chiral stationary phase (CSP) for gas chromatography (GC). Herein, we report the detailed investigation of a chiral MOC ([Cu12(LPA)12(H2O)12], PA = L-phenylalanine, MOC-PA) as a novel stationary phase for GC separations. The MOC-PA capillary column exhibited a high-resolution performance for a wide range of analytes, including n-alkanes, n-alcohols, esters, aromatic compounds and the Grob mixture, positional isomers and racemates. In particular, MOC-PA coated column displayed good resolution and performance for amino acid derivatives. Moreover, the MOC-PA column showed excellent separation repeatability and reproducibility. The relative standard deviation (RSD) values for the retention times were in the range of 0.16-0.30% for run to run (n = 3), 0.31-0.77% for day-to-day (n = 3), and 3.6-4.7% for column-to-column (n = 3), respectively. The experimental results showed that MOC-PA had great potential as a GC stationary phase.

This paper demonstrated a new method for preparing fluorescent molecularly imprinted polymer (MIP) for specific recognition of a target protein. The MIP-based fluorescent receptor was developed by coating MIP layer on the surface of l-cysteine modified Mn2+-doped ZnS quantum dots (QDs) using the surface molecular imprinting process. These MIP-QDs composites demonstrated fast adsorption kinetics, high stability, and good dispersibility in aqueous media. Since the fluorescence quenching of MIP-QDs composites is proportional to the concentration of the lysozyme, the MIP-based fluorescent receptor was successfully applied to the direct fluorescence quantification of lysozyme without further pretreatment. The MIP-based fluorescent receptor exhibited good selectivity and sensitivity for lysozyme detection. The optimum fluorescence intensity of the MIP-QDs was found to be at pH 6.0, and the linear range of lysozyme was from 0.1 to 2.0 μM with the detection limit of 25.2 nM. Moreover, the proposed fluorescent receptor was satisfactorily applied to the determination of lysozyme in real samples. This study provides a new approach for recognizing and detecting of specific proteins in biological samples.

A selective and sensitive electrochemical sensor was proposed on the basis of a nanostructured magnetic molecularly imprinted polymer (CuFe2O4-MIP) modified glassy carbon electrode (GCE) for the electrochemical detection of lysozyme. CuFe2O4 nanospheres with porous structure have been prepared via a hydrothermal method. Surface imprinting was employed to prepare molecularly imprinted polymer nanoparticles on the CuFe2O4 nanosphere surface. The synthesized magnetic nanoparticles (CuFe2O4-MNPs) and CuFe2O4-MIP were characterized with High-Resolution Transmission Electron Microscopy (HRTEM), X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR) and Vibrating Sample Magnetometer (VSM) to verify successful preparation. Then cyclic voltammetry, electrochemical impedance spectroscopy and differential pulse voltammetry were employed to test the electrochemical property of the sensor, and this sensor demonstrated high electrochemical response. The results prove that the as-synthesized CuFe2O4 nanospheres have high specific capacitance characteristics and good conductivity. Under optimal conditions, the constructed multifunctional sensor presented good linearity from 0.05 to 0.8 μg mL−1with the detection limit of 1.58 × 10−3 μg mL−1for target lysozyme. Further competitive rebinding experiments results showed that this sensing material is highly selective and sensitive for lysozyme determination, and had been successfully applied to detect target protein in complex biological samples. The presented method can be applied to the detection of trace protein in biological samples.

Protein imprinting is still a challenge due to the low binding kinetics and poor binding selectivity. In this study, a facile method of the preparation of magnetic molecularly imprinted polymers (MIPs) for selective protein separation was reported. Carboxyl group functionalized Fe $$_{3}$$ O $$_{4}$$ nanoparticles (NPs) were synthesized using a solvothermal method. After pre-assembly of caroxyl group functionalized Fe $$_{3}$$ O $$_{4}$$ NPs and template protein lysozyme (Lyz) to form Lyz–Fe $$_{3}$$ O $$_{4}$$ complex, magnetic MIPs were synthesized by a sol–gel process of 3-aminopropyltriethoxylsilane and tetraethyl silicate with Lyz–Fe $$_{3}$$ O $$_{4}$$ complex incorporated. Then Fe $$_{3}$$ O $$_{4}$$ –MIPs particles with magnetic response could be collected by simple crush of bulk polymers. This preparation process avoid the need of high dilution of monomer for anti-agglomeration in the surface imprinting, and large amount of solvent is spared. The morphology and structure property of the prepared magnetic NPs were characterized by transmission electronic microscopy, Fourier transform infrared spectroscopy, and vibrating sample magnetometer. Binding experiments were carried out to evaluate Fe $$_{3}$$ O $$_{4}$$ –MIPs particles’ binding performance and selectivity. And results showed fast binding kinetics, high binding capacity, and favorable specific recognition behavior toward template protein, which is due to the role of carboxyl group functionalized Fe $$_{3}$$ O $$_{4}$$ NPs as both magnetic source and importantly as co-functional monomer incorporated in the polysiloxane imprinting system. Real egg white sample tests demonstrate good separation effect. This report provides a possibility of the selective separation of protein in complex matrix.

In this study, magnetic fluorescence molecularly imprinted polymers were fabricated and used for the selective separation and fluorescence sensing of trace bisphenol A (BPA) in environmental water samples. The carboxyl-functionalized FeOx magnetic nanoparticles were conjugated with mercaptoethylamine-capped Mn2+ doped ZnS quantum dots to prepare magnetic FeOx and ZnS quantum dot nanoparticles (FeOx/ZnS NPs). Additionally, molecular imprinting on the FeOx/ZnS NPs was employed to synthesize core-shell molecularly imprinted polymers. The resulting nanoparticles were well characterized using transmission electron microscopy, Fourier transform infrared spectra, vibrating sample magnetometer and fluorescence spectra, and the adsorption behavior was investigated. Binding experiments showed that the molecularly imprinted FeOX/ZnS NPs (FeOx/ZnS@MIPs) exhibited rapid fluorescent and magnetic responses, and high selectivity and sensitivity for the detection of bisphenol A (BPA). The maximum adsorption capacity of FeOx/ZnS@MIPs was 50.92 mg&middot, g&minus, 1 with an imprinting factor of 11.19. Under optimal conditions, the constructed fluorescence magnetic molecularly imprinted polymers presented good linearity from 0 to 80 ng mL&minus, 1 with a detection limit of 0.3626 ng mL&minus, 1 for BPA. Moreover, the proposed fluorescence magnetic polymers were successfully applied to on-site magnetic separation and real-time fluorescence analysis of target molecule in real samples.

In this paper, molecularly imprinted photonic crystal hydrogels (MIPHs) were prepared by combining photonic crystals with molecular imprinting technology. The MIPHs were used as optical sensors for the rapid reorganization and detection of melamine in water samples. In this experiment, melamine was used as a template molecule, and the MIPHs were prepared by successive self-assembly, polymerization, and template removal. Morphological characterization by scanning electron microscopy (SEM) showed that the MIPHs possessed a highly ordered three-dimensional (3D) macroporous structure containing nanocavities. As optical sensors, the MIPHs were able to transform molecular recognition events into fluorescence signals for rapid and highly selective and sensitive recognition of the target molecule. Based on color changes of the MIPHs, the target analyte could be quickly identified by analysis with image software or even by observation with the naked eye. Under optimal conditions, the Bragg diffraction peak of the MIPHs shifted from 563 to 608 nm when exposed to melamine in mass concentrations of 10-11 to 10-6mol/L, whereas there were no obvious peak shifts when it was exposed to structural analogues of melamine.