A SERS‐Assisted 3D Barcode Chip for High‐Throughput Biosensing

A surface enhanced Raman scattering (SERS)‐assisted 3D barcode chip has been developed for high‐throughput biosensing. The 3D barcode is realized through joint 2D spatial encoding with the Raman spectroscopic encoding, which stores the SERS fingerprint information in the format of a 2D array. Here, the concept of SERS‐assisted 3D barcode is demonstrated through multiplex immunoassay, where simultaneous detection of multiple targets in different samples has been achieved using a microfluidic platform. First, multiple proteins in different samples are spatially separated using a microfluidic patterned antibody barcode substrate, forming a 2D hybridization array. Then the SERS probes are used to identify and quantify the proteins. As different SERS probes are labeled with different Raman reporters, they could be employed as “SERS tags” to incorporate spectroscopic information into the 3D barcode. In this 3D barcode, the 2D spatial information helps to differentiate the samples and targets while the SERS information allows quantitative multiplex detection. It is found that the SERS‐assisted 3D barcode chip can not only accomplish one‐step multiplex detection within 30 min but also achieve an ultrasensitivity down to 10 fg mL^?1 (≈70 aM), which is expected to provide a promising tool for high‐throughput biomedical applications.     

Hollow Colloid Assembled Photonic Crystal Clusters as Suspension Barcodes for Multiplex Bioassays

Barcode particles have a demonstrated value for multiplexed high‐throughput bioassays. Here, a novel photonic crystal (PhC) barcode is presented that consists of hollow colloidal nanospheres assembled through microfluidic droplet templates. Due to their gas‐filled core, the resultant barcode particles not only show increased refractive index contrast, but also remain in suspension by adjusting the overall density of the PhC to match that of a detection solution. In addition, magnetic nanoparticles can be integrated to give the barcodes a magnetically controllable motion ability. The encoding ability of the barcodes is demonstrated in microRNA detection with high specificity and sensitivity, and the excellent features of the barcodes make them potentially very useful for biomedical applications.     

Engineering of Lanthanide‐Doped Upconversion Nanoparticles for Optical Encoding

Lanthanide‐doped upconversion nanoparticles (UCNPs) are an emerging class of luminescent materials that emit UV or visible light under near infra‐red (NIR) excitations, thereby possessing a large anti‐Stokes shift property. Due to their sharp excitation and emission bands, excellent photo‐ and chemical stability, low autofluorescence, and high tissue penetration depth of the NIR light used for excitation, UCNPs have surpassed conventional fluorophores in many bioapplications. A better understanding of the mechanism of upconversion, as well as the development of better approaches to preparing UCNPs, have provided more opportunities to explore their use for optical encoding, which has the potential for applications in multiplex detection and imaging. With the current ability to precisely control the microstructure and properties of UCNPs to produce particles of tunable emission, excitation, luminescence lifetime, and size, various strategies for optical encoding based on UCNPs can now be developed. These optical properties of UCNPs (such as emission and excitation wavelengths, ratiometric intensity, luminescence lifetime, and multicolor patterns), and the strategies employed to engineer these properties for optical encoding of UCNPs through homogeneous ion doping, heterogeneous structure fabrication and microbead encapsulation are reviewed. The challenges and potential solutions faced by UCNP optical encoding are also discussed.     

Quantum-dot-encoded microbeads for multiplexed genetic detection of non-amplified DNA samples

Barcoding technologies have become the basis for a new generation of molecular diagnostic platforms for measuring biomarkers in a high-throughput, rapid, and sensitive manner. Thus far, researchers have mainly focused on preparing different types of barcodes but, in order to use them optimally in genomic- and proteomic-based applications, there is a need to understand the effect of barcode and assay parameters on their performance. Herein, quantum-dot barcodes are systematically characterized for the detection of non-amplified DNA sequences. The effect of capture probes, reporter probes, and target DNA sequence lengths are studied, as well as the effect of the amount of noncomplementary sequences on the hybridization kinetics and efficiency. From DNA denaturation to signal detection, quantum-dot-barcode assays require less than one hour to detect a target DNA sequence with a linear dynamic range of 0.02-100 fmol. Three optically distinct quantum-dot barcodes are used to demonstrate the multiplexing capability of these barcodes for genomic detection. These results suggest that quantum-dot barcodes are an excellent platform for multiplex, rapid, and sensitive genetic detection.     

Multiplex loop-mediated isothermal amplification detection by sequence-based barcodes coupled with nicking endonuclease-mediated pyrosequencing

The loop-mediated isothermal amplification (LAMP) is a well-developed method for replicating a targeted DNA sequence with a high specificity, but multiplex LAMP detection is difficult because LAMP amplicons are very complicated in structure. To allow simultaneous detection of multiple LAMP products, a series of target-specific barcodes were designed and tagged in LAMP amplicons by FIP primers. The targeted barcodes were decoded by pyrosequencing on nicked LAMP amplicons. To enable the nicking reaction to occur just near the barcode regions, the recognition sequence of the nicking endonuclease (NEase) was also introduced into the FIP primer. After the nicking reaction, pyrosequencing started at the nicked 3' end when the added deoxyribonucleoside triphosphate (dNTP) was complementary to the non-nicked strand. To efficiently encode multiple targets, the barcodes were designed with a reporter base and two stuffer bases, so that the decoding of a target-specific barcode only required a single peak in a pyrogram. We have successfully detected the four kinds of pathogens including hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV), and Treponema pallidum (TP), which are easily infected in blood, by a 4-plex LAMP in a single tube, indicating that barcoded LAMP coupled with NEase-mediated pyrosequencing is a simple, rapid, and reliable way in multiple target identification.     

Terahertz encoding approach for secured chipless radio frequency identification

In this article, we present a new family of chipless tags, which permit encoding of digital data in the terahertz domain. These devices consist of stacked dielectric media whose thicknesses are of the same order as terahertz wavelengths. Since the information is encoded in the volume of these multilayer terahertz tags, they can easily be associated with classical identification techniques (e.g., barcode, radio frequency identification), where information is encoded at the surface of the tag, to provide higher data security. The principle of this encoding approach is studied and experimentally demonstrated in this paper. A 2 bit tag prototype has been realized and measured for validation purposes.     

Nanodisk codes

We report a new encoding system based upon dispersible arrays of nanodisks prepared by on-wire lithography and functionalized with Raman active chromophores. These nanodisk arrays are encoded both physically (in a "barcode" pattern) and spectroscopically (Raman) along the array. These structures can be used in covert encoding strategies because of their small size or as biological labels with readout by scanning confocal Raman spectroscopy. As proof-of-concept, we demonstrate their utility in DNA detection in a multiplexed format at target concentrations as low as 100 fM.     

微／纳米条形码自动电化学合成系统的研制

通过将计算机与电化学相结合,一设计实现了脉冲电沉积、顺序电沉积及任意组合的自动电化学合成系统。通过该系统,可将输入计算机的任意数字编码信息直接转化为实际的编码颗粒,其结构完整清晰,易于解码。目前已获得多种具有特定形貌及组成的纳米条形码。该方法不仅为高效可控制备冽纳米条形码提供了一种新思路,而且在复杂结构的微／纳米材料和智能材料等的设计制备中具有重要的应用前景。     

图像式一维条码识别的三重编码方法

提出一种基于三重编码的图像式一维条码快速识别算法.首先采用最大类间方差法对图像进行二值化分割,将条码从背景中分离出来.对分离出的条码图像实施倾斜校正,然后通过分析二值图像的竖直方向投影特性,建立三重编码,依次为0-1码,类行程码和条空码(条空码根据条码类型进行编码).最后由条空码进行查表和校验.识别过程能够对噪声、不齐、缺损和污染等缺陷进行有效处理.应用结果表明,该算法正确识别率达到99%以上,执行时间仅5ms左右.     

Single-molecule detection and identification of multiple species by multiparameter fluorescence detection

Two general strategies are introduced to identify and quantify single molecules in dilute solutions by employing a spectroscopic method for data registration and specific burst analysis, denoted multiparameter fluorescence detection (MFD). MFD uses pulsed excitation and time-correlated single-photon counting to simultaneously monitor the evolution of the eight-dimensional fluorescence information (fundamental anisotropy, fluorescence lifetime, fluorescence intensity, time, excitation spectrum, fluorescence spectrum, fluorescence quantum yield, distance between fluorophores) in real time and allows for selection of specific events for subsequent analysis. Using the multiple fluorescence dimensions, we demonstrate a dye labeling scheme of oligonucleotides, by which it is possible to identify and separate 16 different compounds in the mixture via their characteristic pattern by MFD. Such identification procedures and multiplex assays with single-molecule sensitivity may have a great impact on screening of species and events that do not lend themselves so easily to amplification, such as disease-specific proteins and their interactions.     

The Horizon of the Emulsion Particulate Strategy: Engineering Hollow Particles for Biomedical Applications

With their hierarchical structures and the substantial surface areas, hollow particles have gained immense research interest in biomedical applications. For scalable fabrications, emulsion‐based approaches have emerged as facile and versatile strategies. Here, the recent achievements in this field are unfolded via an “emulsion particulate strategy,” which addresses the inherent relationship between the process control and the bioactive structures. As such, the interior architectures are manipulated by harnessing the intermediate state during the emulsion revolution (intrinsic strategy), whereas the external structures are dictated by tailoring the building blocks and solidification procedures of the Pickering emulsion (extrinsic strategy). Through integration of the intrinsic and extrinsic emulsion particulate strategy, multifunctional hollow particles demonstrate marked momentum for label‐free multiplex detections, stimuli‐responsive therapies, and stem cell therapies.     

包装印刷品条码质量检测方法

目的为保证商品条码在物流系统中的快速识别和信息传递,研究条码的质量检测方法。方法首先分出条码区域,考虑到条码的特殊属性,需要满足其可识读功能,设计针对EAN-13商品条码的印制质量检测方法,包括可识读检测和印刷缺陷检测。根据条码检测的国家标准,条码可识读检测部分,采用扫描反射率曲线分析法和条码质量分级法对条码的可识读性进行判定。条码缺陷检测部分经过条码校正、条码与字符的分割和条码大小的归一化等处理后,选定基于垂直投影的缺陷检测算法对条码的脱墨和污点缺陷进行检测。结果条码识读程序对合格品和缺陷品的识读准确率都为100%,条码缺陷检测算法程序的平均检测耗时为93.35 ms,检测准确率为94%。结论条码质量检测系统具有较高的检测准确率,并且能够很好地满足机器视觉缺陷检测速度的要求。     

Portable Food-Freshness Prediction Platform Based on Colorimetric Barcode Combinatorics and Deep Convolutional Neural Networks

Artificial scent screening systems (known as electronic noses, E-noses) have been researched extensively. A portable, automatic, and accurate, real-time E-nose requires both robust cross-reactive sensing and fingerprint pattern recognition. Few E-noses have been commercialized because they suffer from either sensing or pattern-recognition issues. Here, cross-reactive colorimetric barcode combinatorics and deep convolutional neural networks (DCNNs) are combined to form a system for monitoring meat freshness that concurrently provides scent fingerprint and fingerprint recognition. The barcodes—comprising 20 different types of porous nanocomposites of chitosan, dye, and cellulose acetate—form scent fingerprints that are identifiable by DCNN. A fully supervised DCNN trained using 3475 labeled barcode images predicts meat freshness with an overall accuracy of 98.5%. Incorporating DCNN into a smartphone application forms a simple platform for rapid barcode scanning and identification of food freshness in real time. The system is fast, accurate, and non-destructive, enabling consumers and all stakeholders in the food supply chain to monitor food freshness.     

Nanostructuring strategies in functional fine-particle synthesis towards resource and energy saving applications

As a low cost and environmentally-benign powder technology, appropriate nanostructuring of fine particles (for example to produce porous, core–shell, hollow, or multicomponent composite structures) has attracted significant attention. Nanostructured fine particles have superior properties, such as high specific surface area, low density, hybrid functionalities, and resistance to weathering. Research into ways of nanostructuring particles for advanced functional materials has progressed rapidly, because these particles offer two great advantages over bulk materials or single component spherical particles: high performance and reduction in the use of expensive raw materials. In particular, the current interest in nanostructured particles focuses on tailoring their inner structure and morphology towards particular practical applications. This article reviews recent research progress on fabrication strategies for nanostructured fine particles. The examples chosen are phosphors, photocatalysts, electrocatalysts, adsorbents and magnetic particles. These fabrication techniques pave the way towards saving both resources and energy in materials production.     

细菌纤维素抗菌复合材料的制备和应用

目的 综述细菌纤维素抗菌复合材料在国内外的研究和应用现状,以制备具有优异抗菌性能的细菌纤维素复合材料.方法 总结细菌纤维素抗菌复合材料的抗菌性及其最新合成方式,包括与无机抗菌剂、有机抗菌剂结合或添加抗生素等方式合成细菌纤维素抗菌复合材料,并进一步阐述细菌纤维素抗菌复合材料的应用领域.结论 细菌纤维素复合材料的抗菌性能优异,在医学、食品包装和净水等领域都有较大的应用潜力,有待进一步系统研究.     

卷烟盒包装二维条码质量现状评估及提升建议

目的 以卷烟盒包装二维条码符号为研究对象,根据标准要求测定评估码制、数据结构、位置、颜色搭配、尺寸和符号等级6个质量参数现状后明确改进思路,以促进印制二维条码符号质量的持续提升,为二维条码符号的推广应用奠定基础。方法 依次对编码后的待测试样按GB/T 23704方法进行单次扫描测定码制、数据内容、版本、符号等级(含7个光学指标)等,然后再通过电子数显卡尺分别测量二维条码符号尺寸及空白区尺寸,最后目测识别二维条码位置和颜色搭配并予以记录。结果 卷烟盒包装二维条码采用QR码,厂商自定义网址数据结构,6种可选位置符合标准要求,但颜色搭配、尺寸和符号等级现状不完全符合标准要求。结论 卷烟盒包装二维条码在选择和编码环节完全符合标准要求,但在产品设计开发和印制过程需结合实际进行优化,以促进其质量提升,从而确保可持续性应用。     

Ionic liquid-assisted synthesis of silica particles and their application in drug release

Hollow and porous silica particles have been successfully prepared by a simple acid gelation route using the sodium silicate as the reactant in ionic liquid solution, 1-butyl-3-methylimidazolium tetrafluoroborate. The drug release behavior of the as-prepared porous silica particles is studied to reveal their potential use in drug delivery system. The current work for the synthesis of silica particles with the sodium silicate as the reactant in an ionic liquid might open new directions and opportunities to explore the application of ionic liquid in materials fields combining with the biomedical area.     

镁基复合材料中常用颗粒增强相研究现状

镁基复合材料具有低的密度、高比强度、比刚度与优异的阻尼性能,是汽车、航空航天等领域的理想化轻量材料,已经成为近年来新材料领域的研究热点。合理有效地选择颗粒增强相对于提升镁基复合材料的性能有着重要的作用。分别从外加法与原位合成法两个方面综述了镁基复合材料颗粒增强相的类型及其对材料力学性能的影响,并对其相应的应用现状进行了分析。最后对颗粒增强相的发展趋势进行了展望。     

Solution-based Chemical Strategies to Purposely Control the Microstructure of Functional Materials

Micro/nanostructured crystals with controlled architectures are desirable for many applications in optics, electronics, biology, medicine, and energy conversions. Low-temperature, aqueous chemical routes have been widely investigated for the synthesis of particles, and arrays of oriented nanorods and nanotubes. In this paper, based on the ideal crystal shapes predicted by the chemical bonding theory, we have developed some potential chemical strategies to tune the microstructure of functional materials, ZnS and Nb205 nanotube arrays, MgO wiskers and nestlike spheres, and cubic phase Cu2O microcrystals were synthesized here to elucidate these strategies. We describe their controlled crystallization processes and illustrate the detailed key factors controlling their growth by examining various reaction parameters. Current results demonstrate that our designed chemical strategies for tuning microstructure of functional materials are applicable to several technologically important materials, and therefore may be used as a versatile and effective route to the controllable synthesis of other inorganic functional materials.     

Sequential Templating Approach: A Groundbreaking Strategy to Create Hollow Multishelled Structures

Thanks to their distinguished properties such as optimized specific surface area, low density, high loading capacity, and sequential matter transfer and storage, hollow multishelled structures (HoMSs) have attracted great interest from scientists in broad fields, including catalysis, drug delivery, solar cells, supercapacitors, lithium‐ion batteries, electromagnetic wave absorption, and sensors. However, traditional synthesis methods such as soft‐templating and hierarchical self‐assembly methods can hardly realize the controllable synthesis of HoMSs, thus limiting their development and application. Here, the development process of HoMSs is first succinctly reviewed and the shortcomings of the traditional synthesis method are concluded. Subsequently, the sequential templating approach, which shows great generality for the synthesis of HoMSs with controllable composition and geometry configuration and exhibits remarkable effect on the scientific research field, is introduced. The basic material science and chemical reaction mechanism involved in the synthesis and manipulation of HoMSs using the sequential templating approach are then explained in detail. In addition, the effect of the geometric characteristics of HoMSs on their application properties is highlighted. Finally, the current challenges and future research directions of HoMSs are also suggested.