RESUMO
The emerging field of organic bioelectronics bridges the electronic world of organic-semiconductor-based devices with the soft, predominantly ionic world of biology. This crosstalk can occur in both directions. For example, a biochemical reaction may change the doping state of an organic material, generating an electronic readout. Conversely, an electronic signal from a device may stimulate a biological event. Cutting-edge research in this field results in the development of a broad variety of meaningful applications, from biosensors and drug delivery systems to health monitoring devices and brain-machine interfaces. Conjugated polymers share similarities in chemical "nature" with biological molecules and can be engineered on various forms, including hydrogels that have Young's moduli similar to those of soft tissues and are ionically conducting. The structure of organic materials can be tuned through synthetic chemistry, and their biological properties can be controlled using a variety of functionalization strategies. Finally, organic electronic materials can be integrated with a variety of mechanical supports, giving rise to devices with form factors that enable integration with biological systems. While these developments are innovative and promising, it is important to note that the field is still in its infancy, with many unknowns and immense scope for exploration and highly collaborative research. The first part of this Account details the unique properties that render conjugated polymers excellent biointerfacing materials. We then offer an overview of the most common conjugated polymers that have been used as active layers in various organic bioelectronics devices, highlighting the importance of developing new materials. These materials are the most popular ethylenedioxythiophene derivatives as well as conjugated polyelectrolytes and ion-free organic semiconductors functionalized for the biological interface. We then discuss several applications and operation principles of state-of-the-art bioelectronics devices. These devices include electrodes applied to sense/trigger electrophysiological activity of cells as well as electrolyte-gated field-effect and electrochemical transistors used for sensing of biochemical markers. Another prime application example of conjugated polymers is cell actuators. External modulation of the redox state of the underlying conjugated polymer films controls the adhesion behavior and viability of cells. These smart surfaces can be also designed in the form of three-dimensional architectures because of the processability of conjugated polymers. As such, cell-loaded scaffolds based on electroactive polymers enable integrated sensing or stimulation within the engineered tissue itself. A last application example is organic neuromorphic devices, an alternative computing architecture that takes inspiration from biology and, in particular, from the way the brain works. Leveraging ion redistribution inside a conjugated polymer upon application of an electrical field and its coupling with electronic charges, conjugated polymers can be engineered to act as artificial neurons or synapses with complex, history-dependent behavior. We conclude this Account by highlighting main factors that need to be considered for the design of a conjugated polymer for applications in bioelectronics-although there can be various figures of merit given the broad range of applications, as emphasized in this Account.
Assuntos
Biologia/métodos , Eletrônica/métodos , Polímeros/química , Biologia/instrumentação , Eletrodos , Eletrônica/instrumentação , Estrutura Molecular , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos , Transistores EletrônicosRESUMO
Field research techniques are constantly evolving to meet the needs of the scientific community. There is a growing need for field biology studies to shift towards increasing efficiency and quality of results while simultaneously decreasing cost in both the researcher's time and resources. I tested the efficacy of using multiple recorded birdcall lures (n = 172 species) to improve mist-net captures at a subtropical African savanna setting. Capture success was compared between passive and birdcall enhanced mist-nets during winter and summer seasons. Results suggest that the use of birdcalls does significantly increase the total number of birds caught in both seasons and also increases the diversity of passerine species. Conventional passive mist-nets without an audio lure were initially productive but their capture rate subsequently decreased as sampling days progressed. Birdcall lure enhanced mist-nets had a constant capture output during the summer season. The most responsive birds to audio lures were gregarious species (e.g. Pycnonotus barbatus, Dryoscopus cubla, Prionops plumatus, Phoeniculus purpureus, Turdoides jardineii and Lamprotornis chalybaeus) and the aggressive Dicrurus adsimilis and Acridotheres tristis. I conclude that birdcall lures can be used in summer and winter seasons to improve mist-net captures especially for studies focusing on gregarious and aggressive passerine species in a sub-tropical African savanna setting.
Assuntos
Biologia/métodos , Passeriformes , Vocalização Animal , Animais , Animais Selvagens , Comportamento Animal , Biologia/instrumentação , Pradaria , África do SulRESUMO
For centuries, designers and engineers have looked to biology for inspiration. Biologically inspired robots are just one example of the application of knowledge of the natural world to engineering problems. However, recent work by biologists and interdisciplinary teams have flipped this approach, using robots and physical models to set the course for experiments on biological systems and to generate new hypotheses for biological research. We call this approach robotics-inspired biology; it involves performing experiments on robotic systems aimed at the discovery of new biological phenomena or generation of new hypotheses about how organisms function that can then be tested on living organisms. This new and exciting direction has emerged from the extensive use of physical models by biologists and is already making significant advances in the areas of biomechanics, locomotion, neuromechanics and sensorimotor control. Here, we provide an introduction and overview of robotics-inspired biology, describe two case studies and suggest several directions for the future of this exciting new research area.
Assuntos
Biologia/métodos , Retroalimentação Sensorial , Locomoção , Robótica/métodos , Biologia/instrumentação , Fenômenos Biomecânicos , Voo AnimalRESUMO
We introduce a robot developed to perform feedback-based experiments, such as droplet experiments, a common type of experiments in artificial chemical life research. These experiments are particularly well suited for automation because they often stretch over long periods of time, possibly hours, and often require that the human takes action in response to observed events such as changes in droplet size, count, shape, or clustering or declustering of multiple droplets. Our robot is designed to monitor long-term experiments and, based on the feedback from the experiment, interact with it. The combination of precise automation, accurately collected experiment data, and integrated analysis and modeling software makes real-time interaction with the experiment feasible, as opposed to traditional offline processing of experiments. Last but not least, we believe the low cost of our platform can promote artificial life research. Furthermore, prevalently, findings from an experiment will inspire redesign for novel experiments. In addition, the robot's open-source software enables easy modification of experiments. We will cover two case studies for application of our robot in feedback-based experiments and demonstrate how our robot can not only automate these experiments, collect data, and interact with the experiments intelligently but also enable chemists to perform formerly infeasible experiments.
Assuntos
Automação Laboratorial/instrumentação , Automação Laboratorial/métodos , Biologia/instrumentação , Biologia/métodos , Robótica/instrumentação , Robótica/métodos , Soluções , HumanosRESUMO
LIGHT SHEET MICROSCOPY IN THE MUSEUM: Light sheet microscopy (or selective plane illumination microscopy) is an important imaging technique in the life sciences. At the same time, this technique is also ideally suited for community outreach projects, because it produces visually appealing, highly dynamic images of living organisms and its working principle can be understood with basic optics knowledge. Still, the underlying concepts are widely unknown to the non-scientific public. On the occasion of the UNESCO International Year of Light, a technical museum in Dresden, Germany, launched a special, interactive exhibition. We built a fully functional, educational selective plane illumination microscope (eduSPIM) to demonstrate how developments in microscopy promote discoveries in biology. DESIGN PRINCIPLES OF AN EDUCATIONAL LIGHT SHEET MICROSCOPE: To maximize educational impact, we radically reduced a standard light sheet microscope to its essential components without compromising functionality and incorporated stringent safety concepts beyond those needed in the lab. Our eduSPIM system features one illumination and one detection path and a sealed sample chamber. We image fixed zebrafish embryos with fluorescent vasculature, because the structure is meaningful to laymen and visualises the optical principles of light sheet microscopy. Via a simplified interface, visitors acquire fluorescence and transmission data simultaneously. THE EDUSPIM DESIGN IS TAILORED EASILY TO FIT NUMEROUS APPLICATIONS: The universal concepts presented here may also apply to other scientific approaches that are communicated to laymen in interactive settings. The specific eduSPIM design is adapted easily for various outreach and teaching activities. eduSPIM may even prove useful for labs needing a simple SPIM. A detailed parts list and schematics to rebuild eduSPIM are provided.
Assuntos
Imageamento Tridimensional/instrumentação , Microscopia/instrumentação , Museus , Animais , Biologia/instrumentação , Embrião não Mamífero , Alemanha , Proteínas de Fluorescência Verde , Luz , Iluminação , Microscopia de Fluorescência/instrumentação , Óptica e Fotônica , Peixe-ZebraRESUMO
Continuous multiphase flow strategies are commonly employed for high-throughput parameter screening of physical, chemical, and biological processes as well as continuous preparation of a wide range of fine chemicals and micro/nano particles with processing times up to 10 min. The inter-dependency of mixing and residence times, and their direct correlation with reactor length have limited the adaptation of multiphase flow strategies for studies of processes with relatively long processing times (0.5-24 h). In this frontier article, we describe an oscillatory multiphase flow strategy to decouple mixing and residence times and enable investigation of longer timescale experiments than typically feasible with conventional continuous multiphase flow approaches. We review current oscillatory multiphase flow technologies, provide an overview of the advancements of this relatively new strategy in chemistry and biology, and close with a perspective on future opportunities.
Assuntos
Biologia/métodos , Química/métodos , Modelos Químicos , Reologia/métodos , Biologia/instrumentação , Biologia/tendências , Química/instrumentação , Química/tendências , Química Clínica/instrumentação , Química Clínica/métodos , Química Clínica/tendências , Humanos , Fluxo Pulsátil , Reologia/instrumentação , Reologia/tendênciasRESUMO
Evolutionary biologists from Darwin forward have dreamed of having data that would elucidate our understanding of evolutionary history and the diversity of life. Sequence capture is a relatively old DNA technology, but its use is growing rapidly due to advances in (i) massively parallel DNA sequencing approaches and instruments, (ii) massively parallel bait construction, (iii) methods to identify target regions and (iv) sample preparation. We give a little historical context to these developments, summarize some of the important advances reported in this special issue and point to further advances that can be made to help fulfill Darwin's dream.
Assuntos
Evolução Biológica , Biologia/história , Biologia/métodos , Variação Genética , Técnicas de Genotipagem/métodos , Biologia/instrumentação , DNA/química , DNA/genética , DNA/isolamento & purificação , Técnicas de Genotipagem/instrumentação , Técnicas de Genotipagem/tendências , Sequenciamento de Nucleotídeos em Larga Escala/instrumentação , Sequenciamento de Nucleotídeos em Larga Escala/métodos , História do Século XX , História do Século XXI , Hibridização de Ácido Nucleico/métodos , Manejo de Espécimes/métodosAssuntos
Biologia/métodos , Radioisótopos de Césio/provisão & distribuição , Laboratórios , Projetos de Pesquisa , Pesquisadores , Medidas de Segurança , Animais , Biologia/instrumentação , Sistema Imunitário/imunologia , Sistema Imunitário/efeitos da radiação , Técnicas Imunológicas/instrumentação , Técnicas Imunológicas/métodos , Internacionalidade , Camundongos , Medidas de Segurança/tendências , Raios XRESUMO
MAIN CONCLUSION: Leaf initiation rate is largely determined by the apical bud temperature even when apical bud temperature largely deviates from the temperature of other plant organs. We have long known that the rate of leaf initiation (LIR) is highly sensitive to temperature, but previous studies in dicots have not rigorously demonstrated that apical bud temperature controls LIR independent of other plant organs temperature. Many models assume that apical bud and leaf temperature are the same. In some environments, the temperature of the apical bud, where leaf initiation occurs, may differ by several degrees Celsius from the temperature of other plant organs. In a 28-days study, we maintained temperature differences between the apical bud and the rest of the individual Cucumis sativus plants from -7 to +8 °C by enclosing the apical buds in transparent, temperature-controlled, flow-through, spheres. Our results demonstrate that LIR was completely determined by apical bud temperature independent of other plant organs temperature. These results emphasize the need to measure or model apical bud temperatures in dicots to improve the prediction of crop development rates in simulation models.
Assuntos
Biologia/métodos , Cucumis sativus/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Biologia/instrumentação , Desenho de Equipamento , Meristema/crescimento & desenvolvimento , TemperaturaRESUMO
The remarkable advances in structural biology in the past three decades have led to the determination of increasingly complex structures that lie at the heart of many important biological processes. Many of these advances have been made possible by the use of X-ray crystallography using synchrotron radiation. In this short article, some of the challenges and prospects that lie ahead will be summarized.
Assuntos
Biologia/instrumentação , Biologia/métodos , Cristalografia por Raios X , Síncrotrons , Química/métodos , Microscopia Crioeletrônica , Escherichia coli/metabolismo , Humanos , Substâncias Macromoleculares , Ácidos Nucleicos/química , Proteínas/química , RobóticaRESUMO
Surface plasmon resonance sensors have made vast advancements in the sensing technology and the number of applications achievable. New developments in surface plasmon resonance sensors have gained considerable momentum promoted by the urgent needs of fast, reliable and label-free methods for detection and quantification of analytes in molecular biology, medicine and other life sciences. However, even if enormous improvements in the limits of detections have been achieved, this technology still faces important challenges to be translated to clinical practice or in-field measurements. This paper reviews the important recent advances of this technology for the label-free detection in real biological samples and we discussed the key challenges to be overcome to transit from prototypes to commercial biosensors.
Assuntos
Biologia/métodos , Ressonância de Plasmônio de Superfície/métodos , Biologia/instrumentação , Diagnóstico , Humanos , Ressonância de Plasmônio de Superfície/instrumentaçãoRESUMO
The European X-ray free-electron laser (XFEL) facility, under construction in the Hamburg region, will provide high-peak brilliance (greater than 10(33) photons s(-1) mm(-2) mrad(-2) per 0.1% BW), ultrashort pulses (approx. 10 fs) of X-rays, with a high repetition rate (up to 27 000 pulses s(-1)) from 2016 onwards. The main features of this exceptional X-ray source, and the instrumentation developments necessary to exploit them fully, for application to a variety of scientific disciplines, are briefly summarized. In the case of structural biology, that has a central role in the scientific case of this new facility, the instruments and ancillary laboratories that are being planned and built within the baseline programme of the European XFEL and by consortia of users are also discussed. It is expected that the unique features of the source and the advanced features of the instrumentation will allow operation modes with more efficient use of sample materials, faster acquisition times, and conditions better approaching feasibility of single molecule imaging.
Assuntos
Biologia/instrumentação , Biologia/métodos , Elétrons , Lasers , Pesquisa , Difração de Raios X/instrumentação , Difração de Raios X/métodos , Europa (Continente)RESUMO
Next-generation X-ray sources, based on the X-ray Free Electron Laser (XFEL) concept, will provide highly coherent, ultrashort pulses of soft and hard X-rays with peak intensity many orders of magnitude higher than that of a synchrotron. These pulses will allow studies of femtosecond dynamics at nanometer resolution and with chemical selectivity. They will produce diffraction images of organic and inorganic nanostructures without deleterious effects of radiation damage.
Assuntos
Lasers , Difração de Raios X/métodos , Biologia/instrumentação , Biologia/métodos , Modelos Teóricos , Fotoquímica/instrumentação , Fotoquímica/métodos , Difração de Raios X/instrumentaçãoRESUMO
Long-term holding and precise handling of growing plant tissues during in vitro cultivation has been a major hurdle for experimental studies related to plant development and reproduction. In the present review, we introduce two of our newly developed poly(dimethylsiloxane)-based microdevices: a T-shaped microchannel device for pollen tube chemoattraction and a microcage array for long-term live imaging of ovules. Their design, usage and advantages are described, and future prospects of experimental approaches to plant reproduction using such microdevices are discussed.