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It has great significance in profiling specific proteins throughout for better understanding of complex pathological processes and in-depth pharmacological studies. In this work, an efficient protein profiling strategy was developed based on the specific protein-drug interaction. Sofosbuvir (SOF), as a first-line drug for the treatment of hepatitis C, was modified onto the surface of nanoparticles through stable chemical bonds to fabricate a novel magnetic separation material denoted as Fe

In this work, a dual-functionalized magnetic bimetallic metal-organic framework composite denoted as Fe3O4@SiO2@(Zr–Ti-MOF)10-NH2 was ingeniously designed and fabricated by a facial layer-by-layer assembly technique. The composite not only exhibited strong affinity for phosphopeptide due to the coexistence of Zr–O clusters and Ti–O clusters, but also owned great hydrophilicity for glycopeptides relying on abundant hydrophilic NH2 groups, meeting the demand for simultaneously enrichment and sequential elution of phosphopeptides and glycopeptides. As expected, the synthesized composite showed great selectivity (1:2000 M ratio of β-casein:BSA; 1:50 M ratio of IgG:BSA), good sensitivity (1 fmol μL−1 for both α-casein and IgG), and good capacity (80 mg g−1 for α-casein and 200 mg g−1 for IgG). By using sequential elution strategy, 29 phosphopeptides and 24 glycopeptides from α-casein and IgG digests mixture could be simultaneously enriched and respectively detected through a single-step enrichment and sequential elution method. Furthermore, the composite was successfully applied to the analysis of intricate biological samples. 4 endogenous phosphopeptides and 20 phosphopeptides were trapped from human serum and non-fat milk tryptic digest respectively. From 0.5 mg of tryptic digest of rat brain, 141 N-linked glycopeptides corresponding to 127 glycoproteins and 918 phosphopeptides corresponding to 397 phosphoproteins were enriched simultaneously and identified respectively, proving the Fe3O4@SiO2@(Zr–Ti-MOF)10-NH2 to be a dependable candidate for the simultaneously enrichment of trace phosphopeptides and glycopeptides in intricate biological samples.

Amplitude-integrated EEG (aEEG) has been widely used in neonatal seizure monitoring due to its convenience and broad applicability. However, due to the long length of aEEG signals, detecting seizures in aEEG signals is still a challenging and time-consuming task for experienced clinicians. In this paper, we propose an ensemble learning algorithm to tackle with this problem, aiming to assist clinicians to identify seizures more efficiently and effectively. Firstly, we employ wavelet denoising method to improve the signal-noise rate (SNR) of aEEG signal. Then, to reduce the high dimensionality of aEEG signals while retaining the essential information, we extract global and local features from aEEG signals based on visual features and entropy. Thereafter, we process our data with a feature augmentation algorithm to obtain an extended data set. Finally, an ensemble algorithm is utilized to perform seizure detection. We conduct experiments on real clinical data collected from Peking University First Hospital. Experimental results show that the proposed algorithm achieves excellent performance in seizure detection.

The highly selective enrichment of phosphopeptides is vital for the research of phosphorylated proteomics. Herein, a magnetic bimetallic metal-organic framework (MOF) with Zr-O and Ti-O clusters (denoted as Fe3O4@SiO2@(Zr-Ti-PTA)15) has been fabricated using a layer-by-layer assembly approach via the coordination of metal ions with carboxyl groups. The composite has large specific surface area (135.84 m2 g−1) and superparamagnetism (62.03 emu g−1). Compared with single-metal cluster MOF, the Fe3O4@SiO2@(Zr-Ti-PTA)15 showed higher binding capacity (100 mg g−1), enhanced affinity, better selectivity (nβ-casein : nBSA = 1 : 2000) and sensitivity (0.3 fmol/μL) towards phosphopeptides due to the combination of the dual metal clusters. Furthermore, the Fe3O4@SiO2@ (Zr-Ti-PTA)15 was successfully applied to extracting phosphopeptides from non-fat milk tryptic digest, and 10 mono-phosphopeptides and 22 multi-phosphopeptides were captured. As a result, 1294 phosphopeptides (476 multi-phosphopeptides and 818 mono-phosphopeptides) were selectively extracted and detected from tryptic digest of rat brain extract, indicating its great application potential in phosphorylated proteomics research.

We present a novel stereo metamaterial composed of three-dimensional (3D) gold split ring resonators (SRRs) in array to realize considerable optical modulation. The metamaterial is fabricated by a general 3D nanofabrication technique of focused ion beam stress induced deformation (FIB-SID). Such technique is a simple-step process, allowing programmable and accurate nanoscale origami on various metal and dielectric thin films. Theoretical and experimental results manifest that the metamaterial device with the 3D SRRs as meta-atoms has reflection minimum and abrupt phase change at 5.3 μm. In addition, to demonstrate the power of FIB-SID, other 3D meta-atoms with complex geometry such as sine shape, fold-line, and swiss-roll are also produced, proving FIB-SID an ideal tool to construct various 3D optical nanostructures and devices, including plamonic antennas, metamaterials and metasurfaces.

3D structures with characteristic lengths ranging from nanometer to micrometer scale often exhibit extraordinary optical properties, and have been becoming an extensively explored field for building new generation nanophotonic devices. Albeit a few methods have been developed for fabricating 3D optical structures, constructing 3D structures with nanometer accuracy, diversified materials, and perfect morphology is an extremely challenging task. This study presents a general 3D nanofabrication technique, the focused ion beam stress induced deformation process, which allows a programmable and accurate bidirectional folding (-70°-+90°) of various metal and dielectric thin films. Using this method, 3D helical optical antennas with different handedness, improved surface smoothness, and tunable geometries are fabricated, and the strong optical rotation effects of single helical antennas are demonstrated.