共查询到20条相似文献,搜索用时 0 毫秒
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Two-photon microscopy (TPM), which uses two photons of lower energy as the excitation source, is a vital tool in biology and clinical science, due to its capacity to image deep inside intact tissues for a long period of time. To make TPM a more versatile tool in biomedical research, we have developed a variety of two-photon probes for specific applications. In this mini review, we will briefly discuss two-photon probes for lipid rafts, lysosomes, mitochondria, and pH, and their biomedical applications. [BMB Reports 2013; 46(4): 188-194] 相似文献
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Jana M. Say Caryn van Vreden David J. Reilly Louise J. Brown James R. Rabeau Nicholas J. C. King 《Biophysical reviews》2011,3(4):171-184
In recent years, nanodiamonds have emerged from primarily an industrial and mechanical applications base, to potentially underpinning sophisticated new technologies in biomedical and quantum science. Nanodiamonds are relatively inexpensive, biocompatible, easy to surface functionalise and optically stable. This combination of physical properties are ideally suited to biological applications, including intracellular labelling and tracking, extracellular drug delivery and adsorptive detection of bioactive molecules. Here we describe some of the methods and challenges for processing nanodiamond materials, detection schemes and some of the leading applications currently under investigation. 相似文献
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A class of organic polymers, known as conducting polymers (CPs), has become increasingly popular due to its unique electrical and optical properties. Material characteristics of CPs are similar to those of some metals and inorganic semiconductors, while retaining polymer properties such as flexibility, and ease of processing and synthesis, generally associated with conventional polymers. Owing to these characteristics, research efforts in CPs have gained significant traction to produce several types of CPs since its discovery four decades ago. CPs are often categorised into different types based on the type of electric charges (e.g., delocalized pi electrons, ions, or conductive nanomaterials) responsible for conduction. Several CPs are known to interact with biological samples while maintaining good biocompatibility and hence, they qualify as interesting candidates for use in a numerous biological and medical applications. In this paper, we focus on CP-based sensor elements and the state-of-art of CP-based sensing devices that have potential applications as tools in clinical diagnosis and surgical interventions. Representative applications of CP-based sensors (electrochemical biosensor, tactile sensing 'skins', and thermal sensors) are briefly discussed. Finally, some of the key issues related to CP-based sensors are highlighted. 相似文献
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H Seliger A Fr?hlich G Gr?ger B Krist M Montenarh H R?sch R R?sch F R Ortigao 《Nucleic acids symposium series》1991,(24):193-196
New developments of oligonucleotides for biomedical applications are surveyed. Diagnostic probes were conveniently labelled by enzymatic immunogenic tailing with 5-bromo-deoxyuridine triphosphate. "Antisense" oligonucleotides of potential therapeutic value were stabilized against nucleolytic decay by inversion of terminal internucleotidic linkages. Introduction of 2'-deoxy-2'-fluoro-nucleotide units enhances duplex stability and conveys resistance to ribonucleases. 相似文献
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The application of organic polymers and inorganic/organic hybrid systems in numerous fields of biotechnology has seen a considerable growth in recent years. Typically, organic polymers with diverse structures, compositional variations and differing molecular weights have been utilized to assemble polymeric nanosystems such as polymeric micelles, polymersomes, and nanohydrogels with unique features and structural properties. The architecture of these polymeric nanosystems involves the use of both hydrophobic and hydrophilic polymeric blocks, making them suitable as vehicles for diagnostic and therapeutic applications. Recently, “smart” or “intelligent” polymers have attracted significant attention in the biomedical field wherein careful introduction of specific polymeric modalities changes a banal polymeric nanosystem to an advanced stimuli-responsive nanosystem capable of performing extraordinary functions in response to an internal or external trigger such as pH, temperature, redox, enzymes, light, magnetic, or ultrasound. Further, incorporation of inorganic nanoparticles such as gold, silica, or iron oxide with surface-bound stimuli-responsive polymers offers additional advantages and multifunctionality in the field of nanomedicine. This review covers the physical properties and applications of both organic and organic/inorganic hybrid nanosystems with specific recent breakthroughs in drug delivery, imaging, tissue engineering, and separations and provides a brief discussion on the future direction. 相似文献
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Water-soluble quantum dots for biomedical applications 总被引:6,自引:0,他引:6
Yu WW Chang E Drezek R Colvin VL 《Biochemical and biophysical research communications》2006,348(3):781-786
Semiconductor nanocrystals are 1-10nm inorganic particles with unique size-dependent optical and electrical properties due to quantum confinement (so they are also called quantum dots). Quantum dots are new types of fluorescent materials for biological labeling with high quantum efficiency, long-term photostability, narrow emission, and continuous absorption spectra. Here, we discuss the recent development in making water-soluble quantum dots and related cytotoxicity for biomedical applications. 相似文献
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Free radical species generated through fluorescence photobleaching have been reported to effectively couple a water-soluble species to surfaces containing electron-rich sites . In this report, we expand upon this strategy to control the patterned attachment of antibodies and peptides to surfaces for biosensing and tissue engineering applications. In the first application, we compare hydrophobic attachment and photobleaching methods to immobilize FITC-labeled anti-M13K07 bacteriophage antibodies to the SiO2 layer of a differential capacitive biosensor and to the polyester filament of a feedback-controlled filament array. On both surfaces, antibody attachment and function were superior to the previously employed hydrophobic attachment. Furthermore, a laser scanning confocal microscope could be used for automated, software-guided photoattachment chemistry. In a second application, the cell-adhesion peptide RGDS was site-specifically photocoupled to glass coated with fluorescein-conjugated poly(ethylene glycol). RGDS attachment and bioactivity were characterized by a fibroblast adhesion assay. Cell adhesion was limited to sites of RGDS photocoupling. These examples illustrate that fluorophore-based photopatterning can be achieved by both solution-phase fluorophores or surface-adhered fluorophores. The coupling preserves the bioactivity of the patterned species, is amenable to a variety of surfaces, and is readily accessible to laboratories with fluorescence imaging equipment. The flexibility offered by visible light patterning will likely have many useful applications in bioscreening and tissue engineering where the controlled placement of biomolecules and cells is critical, and should be considered as an alternative to chemical coupling methods. 相似文献
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Temperature strongly influences the form and function of biologically important macromolecules and cells. Advances in microfabrication technology have enabled highly localized and accurate temperature control and manipulation, allowing the investigation of thermal effects on biological microsystems. This paper reviews progress in this field, with emphasis on techniques and microdevices with biomedical applications. Recent advances in the study of thermal effects on cellular behavior, enabled by MEMS-based structures are reported. These studies focus on investigating thermal interactions between the cell and its microenvironment. Thermal-based tools for concentration and purification of biologically important macromolecules like DNA and proteins are summarized. These tools address common issues in protein/DNA research, like concentration, separation and purification of samples. With the increasing research focus on the integration of biomedicine with engineering technologies and the several incentives of miniaturization, MEMS-based devices are likely to become increasingly prevalent in biology and medicine. Thermal engineering is expected to continue to play an important role in the improvement of current microdevices and the development of new ones. 相似文献
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Although used for analytical purposes for more than 40 years it is only recently that biochemiluminescence (BCL) has found widespread acceptance. Methods employing BCL reactions now play an important role in biomedical research and laboratory medicine. The main attractions for the assay technology include exquisite sensitivity (attomole-zeptomole), high selectivity, speed and simplicity. In biomedical research, the most important applications of BCL are: (1) to estimate microbial numbers and to assess cellular states (e.g., after exposure to antibiotic or cytotoxic agents) and in reporter gene studies (firefly luciferase gene); (2) NAD(P)H involved in redox/dehydrogenase studies usingVibrio luciferase complex; (3) BCL labels and CL detection of enzyme labels in immunoassays are the most widespread routine application for this technology. BCL enzyme immunoassays represent the most active area of development, e.g., enhanced BCL method for peroxidase and BCL assays for alkaline phosphatase labels using adamantyl 1,2-dioxetane.Abbreviations BCL
biochemiluminescence
- CL
chemiluminescence
- RLU
relative light unit
- ROS
reactive oxygen species 相似文献
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Philippe Zinck 《Reviews in Environmental Science and Biotechnology》2009,8(3):231-234
Polyesters are widely used for biomedical applications such as drug delivery systems and resorbable implants. The degradation
kinetic of these biopolymers can be tailored by the introduction of functional groups in their backbone, leading to a modification
of their morphology and hydrophilicity. This is usually realized via long multistep reaction pathways. This contribution describes
the emergence of one-step procedures for this purpose including enzymatic and Lewis acid catalyzed polycondensation as well
as coordinative ring opening polymerization. 相似文献
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Organoids are in vitro cultures of miniature fetal or adult organ-like structures. Their potentials for use in tissue and organ replacement, disease modeling, toxicology studies, and drug discovery are tremendous. Currently, major challenges facing human organoid technology include (i) improving the range of cellular heterogeneity for a particular organoid system, (ii) mimicking the native micro- and matrix-environment encountered by cells within organoids, and (iii) developing robust protocols for the in vitro maturation of organoids that remain mostly fetal-like in cultures. To tackle these challenges, we advocate the principle of reverse engineering that replicates the inner workings of in vivo systems with the goal of achieving functionality and maturation of the resulting organoid structures with the input of minimal intrinsic (cellular) and environmental (matrix and niche) constituents. Here, we present an overview of organoid technology development in several systems that employ cell materials derived from fetal and adult tissues and pluripotent stem cell cultures. We focus on key studies that exploit the self-organizing property of embryonic progenitors and the role of designer matrices and cell-free scaffolds in assisting organoid formation. We further explore the relationship between adult stem cells, niche factors, and other current developments that aim to enhance robust organoid maturation. From these works, we propose a standardized pipeline for the development of future protocols that would help generate more physiologically relevant human organoids for various biomedical applications. 相似文献
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《Journal of Biomedical Engineering》1991,13(3):234-238
The subject of electro-rheology is introduced to biological engineers in a concise manner to allow presentation of a procedure for effective quantitative evaluation of possible medical applications of this new technology. More detailed phenomena are included in the references. Characteristics of the current best available fluid are given in brief. 相似文献
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This paper presents a review of acoustic-wave based MEMS devices that offer a promising technology platform for the development of sensitive, portable, real-time biosensors. MEMS fabrication of acoustic wave based biosensors enables device miniaturization, power consumption reduction and integration with electronic circuits. For biological applications, the biosensors are integrated in a microfluidic system and the sensing area is coated with a biospecific layer. When a bioanalyte interacts with the sensing layer, mass and viscosity variations of the biospecific layer can be detected by monitoring changes in the acoustic wave properties such as velocity, attenuation, resonant frequency and delay time. Few types of acoustic wave devices could be integrated in microfluidic systems without significant degradation of the quality factor. The acoustic wave based MEMS devices reported in the literature as biosensors and presented in this review are film bulk acoustic wave resonators (FBAR), surface acoustic waves (SAW) resonators and SAW delay lines. Different approaches to the realization of FBARs, SAW resonators and SAW delay lines for various biochemical applications are presented. Methods of integration of the acoustic wave MEMS devices in the microfluidic systems and functionalization strategies will be also discussed. 相似文献
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We present a novel method to fabricate silk fibroin hydrogels using high pressure carbon dioxide (CO(2)) as a volatile acid without the need for chemical cross-linking agents or surfactants. The simple and efficient recovery of CO(2) post processing results in a remarkably clean production method offering tremendous benefit toward materials processing for biomedical applications. Further, with this novel technique we reveal that silk protein gelation can be considerably expedited under high pressure CO(2) with the formation of extensive β-sheet structures and stable hydrogels at processing times less than 2 h. We report a significant influence of the high pressure CO(2) processing environment on silk hydrogel physical properties such as porosity, sample homogeneity, swelling behavior and compressive properties. Microstructural analysis revealed improved porosity and homogeneous composition among high pressure CO(2) specimens in comparison to the less porous and heterogeneous structures of the citric acid control gels. The swelling ratios of silk hydrogels prepared under high pressure CO(2) were significantly reduced compared to the citric acid control gels, which we attribute to enhanced physical cross-linking. Mechanical properties were found to increase significantly for the silk hydrogels prepared under high pressure CO(2), with a 2- and 3-fold increase in the compressive modulus of the 2 and 4 wt % silk hydrogels over the control gels, respectively. We adopted a semiempirical theoretical model to elucidate the mechanism of silk protein gelation demonstrated here. Mechanistically, the rate of silk protein gelation is believed to be a function of the kinetics of solution acidification from absorbed CO(2) and potentially accelerated by high pressure effects. The attractive features of the method described here include the acceleration of stable silk hydrogel formation, free of residual mineral acids or chemical cross-linkers, reducing processing complexity, and avoiding adverse biological responses, while providing direct manipulation of hydrogel physical properties for tailoring toward specific biomedical applications. 相似文献