微型生物在水环境监测中的应用

微型生物是水生态系统的重要组成部分,对外界环境变化的敏感性使微型生物成为生物监测的良好受试对象。本文探讨了微型生物在水环境监测中的优势以及应用进展,展望了微型生物在水环境中的应用前景。     

生物监测技术在水环境工程中的应用及研究

自然界的水环境是通过各种形式的循环实现跨空间的各类水形态的转化。水环境与人的生活息息相关,能直接或间接地影响人类的生活。水生态环境的污染和破坏导致生物多样性减少,影响人和其他生物的健康。利用生物监测技术对水环境加强监测,通过监测结果了解和掌握更多的水环境现状,从而实施针对性的水环境污染治理。本文介绍了生物监测技术的原理及其在水环境中应用的作用,探讨了水环境工程的中的监测内容,根据监测内容分析生物监测技术在水环境工程中的应用。旨在为水环境保护与污染控制工程的系统化建设提供一些参考。     

青岛市生物监测现状与应用研究

生物监测是环境监测的重要内容。2019年青岛市对三大水库开展了生物群落分析,为水源地保护提供了数据支撑。生物监测作为化学监测的补充在未来的环境监测中将发挥越来越大的作用,监测领域也将从水环境向空气、土壤环境拓展,监测方法也将多样化。     

基于无线传感器网络的水环境监测信息融合研究

将无线传感器网络技术引入水环境监测系统中,并通过研究和解决相关理论方法与技术有效提高水环境监测系统的整体效能。本文主要研究基于无线网络的水环境监测信息融合处理系统结构模型,并提出有效的多源信息融合方法、多传感器管理及协调控制策略。     

生物传感器的进展综述

生物传感器技术在医学领域中有广阔的应用前景,它具有专一、灵敏、响应快等特点,本文简要介绍了生物传感器的工作原理、分类,探讨了生物传感器的研究进展及应用前景.     

生物传感器的进展综述

生物传感器技术在医学领域中有广阔的应用前景，它具有专一、灵敏、响应快等特点，本文简要介绍了生物传感器的工作原理、分类，探讨了生物传感器的研究进展及应用前景。     

重大工程结构智能传感网络与健康监测系统的研究与应用

本文重点介绍了我国,特别是哈尔滨工业大学近年来有关重大工程结\\r 构智能传感网络与健康监测系统的一些研究与应用成果。主要内容包括：光纤光栅应变和温 度传感器、压电薄膜（PVDF）应变和裂缝监测传感器、疲劳累积传感器、形状记忆合金传感 器等智能传感器研究与应用; 无线传感器网络与无线传输技术及其工程应用; 碳纤维筋式 传感器与纤维增强?光纤光栅复合筋式应变传感器研究开发与应用;碳纤维和(或)纳米粒子 添料 形成的自感知水泥砂浆及其混凝土标准应变传感器的研究与开发;智能健康监测系统及其在 海洋平台结构、混凝土坝面、大跨桥梁以及大跨空间结构等实际工程中的应用。最后,介绍 了我国在重大工程结构智能健康监测领域方面研究立项的情况,并指出了进一步值得研究的 一些问题。     

生物传感发展50年及展望

生物传感器是由生物元件与物理和化学换能器件构成的分析装置,属于典型的交叉学科和汇聚技术。生物传感器具有快速、准确、简便的特点,并借助微阵列平台技术(生物芯片)实现了高通量分析,在生命科学研究、疾病诊断和监控、生物过程控制、农业与食品安全、环境质量监控、生物安全与生物安保等领域有广阔的应用前景。经历50年后,生物传感进入一个新的蓬勃发展阶段,主要驱动因素是大健康、物联网、大数据等概念的提出与实施;研究热点包括穿戴式和便携式,即时检测(POCT)、无创分析、活体测定、在线检测、现场监测、超高时空分辨和单细胞生物学应用等。不同的应用场景存在不同的技术难题,其中生物元件的稳定性是共性问题,尚待攻克。中国学者在生物传感领域的研究论文影响力总体上已经进入国际第一方阵,下一步目标是学术上实现卓越和引领,并大幅提升全球市场开发能力,贡献大健康。     

水生生物在我国水环境监测工作中的作用及发展

阐述了我国水环境监测工作以理化手段为主的现状与原因,论述了水生生物在水环境监测工作中的重要性,针对现今工作开展中存在的一些困难及问题简要提出了将水生生物应用于水环境监测工作中的发展方向。     

无线传感器网络研究

无线传感器网络集成了传感器、微机电系统和网络三大技术而形成的传感器网络是一种全新的信息获取和处理技术,已经成为当今的热门研究领域之一,在国防安全、工农业领域各种控制、城市管理、生物医疗、环境监测、抢险救灾、防恐反恐、危险区域远程控制等许多领域都有重要的科研价值和实用价值,具有十分广阔的应用前景。本文讨论了无线传感器网络的基本概念和一些重要研究领域,并且介绍了无线传感器网络与IPv6的可能的一些契合点,它是无线传感器网络进行大规模就用的重要议题。     

分子生物传感器与细胞内分子影像

分子生物传感器是由生物大分子通过基因重组或DNA合成所构成的传感器,能够实时、可视化探测活细胞及活体内关键分子事件。目前研究热度高、应用广的分子生物传感器包括分子信标(MB)、共振能量转移系统(荧光共振能量转移和生物发光共振能量转移)和分子荧光互补系统(如双分子荧光互补、三分子荧光互补等)。文章介绍了这几类分子生物传感器的原理和特点,重点强调了它们在活细胞分子影像学中的运用,如:研究细胞内蛋白之间的相互作用,探索生物大分子在细胞中的定位、运动和动力学等。此外,还讨论了分子生物传感器的局限性和面临的挑战,并展望了未来发展方向。"眼见为实",分子生物传感器在这方面发挥独特的作用,它使我们前所未有地深入到细胞内部去观察生物分子事件乃至生物学过程,从而解答更多的生物学难题。     

Exploitation of physical and chemical constraints for three-dimensional microtissue construction in microfluidics

There are a plethora of approaches to construct microtissues as building blocks for the repair and regeneration of larger and complex tissues. Here we focus on various physical and chemical trapping methods for engineering three-dimensional microtissue constructs in microfluidic systems that recapitulate the in vivo tissue microstructures and functions. Advances in these in vitro tissue models have enabled various applications, including drug screening, disease or injury models, and cell-based biosensors. The future would see strides toward the mesoscale control of even finer tissue microstructures and the scaling of various designs for high throughput applications. These tools and knowledge will establish the foundation for precision engineering of complex tissues of the internal organs for biomedical applications.     

Review Article��Dielectrophoresis: Status of the theory, technology, and applications

A review is presented of the present status of the theory, the developed technology and the current applications of dielectrophoresis (DEP). Over the past 10 years around 2000 publications have addressed these three aspects, and current trends suggest that the theory and technology have matured sufficiently for most effort to now be directed towards applying DEP to unmet needs in such areas as biosensors, cell therapeutics, drug discovery, medical diagnostics, microfluidics, nanoassembly, and particle filtration. The dipole approximation to describe the DEP force acting on a particle subjected to a nonuniform electric field has evolved to include multipole contributions, the perturbing effects arising from interactions with other cells and boundary surfaces, and the influence of electrical double-layer polarizations that must be considered for nanoparticles. Theoretical modelling of the electric field gradients generated by different electrode designs has also reached an advanced state. Advances in the technology include the development of sophisticated electrode designs, along with the introduction of new materials (e.g., silicone polymers, dry film resist) and methods for fabricating the electrodes and microfluidics of DEP devices (photo and electron beam lithography, laser ablation, thin film techniques, CMOS technology). Around three-quarters of the 300 or so scientific publications now being published each year on DEP are directed towards practical applications, and this is matched with an increasing number of patent applications. A summary of the US patents granted since January 2005 is given, along with an outline of the small number of perceived industrial applications (e.g., mineral separation, micropolishing, manipulation and dispensing of fluid droplets, manipulation and assembly of micro components). The technology has also advanced sufficiently for DEP to be used as a tool to manipulate nanoparticles (e.g., carbon nanotubes, nano wires, gold and metal oxide nanoparticles) for the fabrication of devices and sensors. Most efforts are now being directed towards biomedical applications, such as the spatial manipulation and selective separation∕enrichment of target cells or bacteria, high-throughput molecular screening, biosensors, immunoassays, and the artificial engineering of three-dimensional cell constructs. DEP is able to manipulate and sort cells without the need for biochemical labels or other bioengineered tags, and without contact to any surfaces. This opens up potentially important applications of DEP as a tool to address an unmet need in stem cell research and therapy.     

Utilizing microfluidics to synthesize polyethylene glycol microbeads for Förster resonance energy transfer based glucose sensing

Here, we utilize microfluidic droplet technology to generate photopolymerizeable polyethylene glycol (PEG) hydrogel microbeads incorporating a fluorescence-based glucose bioassay. A microfluidic T-junction and multiphase flow of fluorescein isothiocyanate dextran, tetramethyl rhodamine isothiocyanate concanavalin A, and PEG in water were used to generate microdroplets in a continuous stream of hexadecane. The microdroplets were photopolymerized mid-stream with ultraviolet light exposure to form PEG microbeads and were collected at the outlet for further analysis. Devices were prototyped in PDMS and generated highly monodisperse 72?±?2 μm sized microbeads (measured after transfer into aqueous phase) at a continuous flow rate between 0.04 ml/h-0.06 ml/h. Scanning electron microscopy analysis was conducted to analyze and confirm microbead integrity and surface morphology. Glucose sensing was carried out using a F?rster resonance energy transfer (FRET) based assay. A proportional fluorescence intensity increase was measured within a 1-10 mM glucose concentration range. Microfluidically synthesized microbeads encapsulating sensing biomolecules offer a quick and low cost method to generate monodisperse biosensors for a variety of applications including cell cultures systems, tissue engineering, etc.     

Recent developments in microfluidic synthesis of artificial cell-like polymersomes and liposomes for functional bioreactors

Recent advances in droplet microfluidics have led to the fabrication of versatile vesicles with a structure that mimics the cellular membrane. These artificial cell-like vesicles including polymersomes and liposomes effectively enclose an aqueous core with well-defined size and composition from the surrounding environment to implement various biological reactions, serving as a diverse functional reactor. The advantage of realizing various biological phenomena within a compartment separated by a membrane that resembles a natural cell membrane is actively explored in the fields of synthetic biology as well as biomedical applications including drug delivery, biosensors, and bioreactors, to name a few. In this Perspective, we first summarize various methods utilized in producing these polymersomes and liposomes. Moreover, we will highlight some of the recent advances in the design of these artificial cell-like vesicles for functional bioreactors and discuss the current issues and future perspectives.     

Lipid–oligonucleotide conjugates for bioapplications

Lipid–oligonucleotide conjugates (LONs) are powerful molecular-engineering materials for various applications ranging from biosensors to biomedicine. Their unique amphiphilic structures enable the self-assembly and the conveyance of information with high fidelity. In particular, LONs present remarkable potential in measuring cellular mechanical forces and monitoring cell behaviors. LONs are also essential sensing tools for intracellular imaging and have been employed in developing cell-surface-anchored DNA nanostructures for biomimetic-engineering studies. When incorporating therapeutic oligonucleotides or small-molecule drugs, LONs hold promise for targeted therapy. Moreover, LONs mediate the controllable assembly and fusion of vesicles based on DNA-strand displacements, contributing to nanoreactor construction and macromolecule delivery. In this review, we will summarize the general synthesis strategies of LONs, provide some characterization analysis and emphasize recent advances in bioanalytical and biomedical applications. We will also consider the relevant challenges and suggest future directions for building better functional LONs in nanotechnology and materials-science applications.     

Utilizing microfluidics to synthesize polyethylene glycol microbeads for F?rster resonance energy transfer based glucose sensing

Here, we utilize microfluidic droplet technology to generate photopolymerizeable polyethylene glycol (PEG) hydrogel microbeads incorporating a fluorescence-based glucose bioassay. A microfluidic T-junction and multiphase flow of fluorescein isothiocyanate dextran, tetramethyl rhodamine isothiocyanate concanavalin A, and PEG in water were used to generate microdroplets in a continuous stream of hexadecane. The microdroplets were photopolymerized mid-stream with ultraviolet light exposure to form PEG microbeads and were collected at the outlet for further analysis. Devices were prototyped in PDMS and generated highly monodisperse 72 ± 2 μm sized microbeads (measured after transfer into aqueous phase) at a continuous flow rate between 0.04 ml/h—0.06 ml/h. Scanning electron microscopy analysis was conducted to analyze and confirm microbead integrity and surface morphology. Glucose sensing was carried out using a Förster resonance energy transfer (FRET) based assay. A proportional fluorescence intensity increase was measured within a 1–10 mM glucose concentration range. Microfluidically synthesized microbeads encapsulating sensing biomolecules offer a quick and low cost method to generate monodisperse biosensors for a variety of applications including cell cultures systems, tissue engineering, etc.     

A nanoporous optofluidic microsystem for highly sensitive and repeatable surface enhanced Raman spectroscopy detection

We report the demonstration of an optofluidic surface enhanced Raman spectroscopy (SERS) device that leverages a nanoporous microfluidic matrix to improve the SERS detection performance by more than two orders of magnitude as compared to a typical open microfluidic channel. Although it is a growing trend to integrate optical biosensors into microfluidic channels, this basic combination has been detrimental to the sensing performance when applied to SERS. Recently, however, synergistic combinations between microfluidic functions and photonics (i.e., optofluidics) have been implemented that improve the detection performance of SERS. Conceptually, the simplest optofluidic SERS techniques reported to date utilize a single nanofluidic channel to trap nanoparticle-analyte conjugates as a method of preconcentration before detection. In this work, we leverage this paradigm while improving upon the simplicity by forming a 3D nanofluidic network with packed nanoporous silica microspheres in a microfluidic channel; this creates a concentration matrix that traps silver nanoclusters and adsorbed analytes into the SERS detection volume. With this approach, we are able to achieve a detection limit of 400 attomoles of Rhodamine 6G after only 2 min of sample loading with high chip-to-chip repeatability. Due to the high number of fluidic paths in the nanoporous channel, this approach is less prone to clogging than single nanofluidic inlets, and the loading time is decreased compared to previous reports. In addition, fabrication of this microsystem is quite simple, as nanoscale fabrication is not necessary. Finally, integrated multimode fiber optic cables eliminate the need for optical alignment, and thus the device is relevant for portable and automated applications in the field, including point-of-sample and point-of-care detection. To illustrate a relevant field-based application, we demonstrate the detection of 12 ppb of the organophosphate malathion in water using the nanofluidic SERS microsystem.     

Integrated dynamic wet spinning of core-sheath hydrogel fibers for optical-to-brain/tissue communications

Hydrogel optical light-guides have received substantial interest for applications such as deep-tissue biosensors, optogenetic stimulation and photomedicine due to their biocompatibility, (micro)structure control and tissue-like Young''s modulus. However, despite recent developments, large-scale fabrication with a continuous synthetic methodology, which could produce core-sheath hydrogel fibers with the desired optical and mechanical properties suitable for deep-tissue applications, has yet to be achieved. In this study, we report a versatile concept of integrated light-triggered dynamic wet spinning capable of continuously producing core-sheath hydrogel optical fibers with tunable fiber diameters, and mechanical and optical propagation properties. Furthermore, this concept also exhibited versatility for various kinds of core-sheath functional fibers. The wet spinning synthetic procedure and fabrication process were optimized with the rational design of the core/sheath material interface compatibility [core = poly(ethylene glycol diacrylate-co-acrylamide); sheath = Ca-alginate], optical transparency, refractive index and spinning solution viscosity. The resulting hydrogel optical fibers exhibited desirable low optical attenuation (0.18 ± 0.01 dB cm⁻¹ with 650 nm laser light), excellent biocompatibility and tissue-like Young''s modulus (<2.60 MPa). The optical waveguide hydrogel fibers were successfully employed for deep-tissue cancer therapy and brain optogenetic stimulation, confirming that they could serve as an efficient versatile tool for diverse deep-tissue therapy and brain optogenetic applications.