BioMEMS

As technological advancements widen the scope of applications for biomicroelectromechanical systems (BioMEMS or biomicrosystems), the field continues to have an impact on many aspects of life science operations and functionalities. Because BioMEMS research and development require the input of experts who use different technical languages and come from varying disciplines and backgrounds, scientists and students can avoid potential difficulties in communication and understanding only if they possess a skill set and understanding that enables them to work at the interface of engineering and biosciences. Keeping this duality in mind throughout, BioMEMS: Science and Engineering Perspectives supports and expedites the multidisciplinary learning involved in the development of biomicrosystems. Divided into nine chapters, it starts with a balanced introduction of biological, engineering, application, and commercialization aspects of the field. With a focus on molecules of biological interest, the book explores the building blocks of cells and viruses, as well as molecules that form the self-assembled monolayers (SAMs), linkers, and hydrogels used for making different surfaces biocompatible through functionalization. The book also discusses: Different materials and platforms used to develop biomicrosystems Various biological entities and pathogens (in ascending order of complexity) The multidisciplinary aspects of engineering bioactive surfaces Engineering perspectives, including methods of manufacturing bioactive surfaces and devices Microfluidics modeling and experimentation Device level implementation of BioMEMS concepts for different applications. Because BioMEMS is an application-driven field, the book also highlights the concepts of lab-on-a-chip (LOC) and micro total analysis system (μTAS), along with their pertinence to the emerging point-of-care (POC) and point-of-need (PON) applications

BioMEMS

As technological advancements widen the scope of applications for biomicroelectromechanical systems (BioMEMS or biomicrosystems), the field continues to have an impact on many aspects of life science operations and functionalities. Because BioMEMS research and development require the input of experts who use different technical languages and come from varying disciplines and backgrounds, scientists and students can avoid potential difficulties in communication and understanding only if they possess a skill set and understanding that enables them to work at the interface of engineering and biosciences. Keeping this duality in mind throughout, BioMEMS: Science and Engineering Perspectives supports and expedites the multidisciplinary learning involved in the development of biomicrosystems. Divided into nine chapters, it starts with a balanced introduction of biological, engineering, application, and commercialization aspects of the field. With a focus on molecules of biological interest, the book explores the building blocks of cells and viruses, as well as molecules that form the self-assembled monolayers (SAMs), linkers, and hydrogels used for making different surfaces biocompatible through functionalization. The book also discusses: Different materials and platforms used to develop biomicrosystems Various biological entities and pathogens (in ascending order of complexity) The multidisciplinary aspects of engineering bioactive surfaces Engineering perspectives, including methods of manufacturing bioactive surfaces and devices Microfluidics modeling and experimentation Device level implementation of BioMEMS concepts for different applications. Because BioMEMS is an application-driven field, the book also highlights the concepts of lab-on-a-chip (LOC) and micro total analysis system (μTAS), along with their pertinence to the emerging point-of-care (POC) and point-of-need (PON) applications

Plasmonic Gold Decorated MWCNT Nanocomposite for Localized Plasmon Resonance Sensing

The synergism of excellent properties of carbon nanotubes and gold nanoparticles is used in this work for bio-sensing of recombinant bovine growth hormones (rbST) by making Multi Wall Carbon Nanotubes (MWCNT) locally optically responsive by augmenting it optical properties through Localized Surface Plasmon Resonance (LSPR). To this purpose, locally gold nano particles decorated gold–MWCNT composite was synthesized from a suspension of MWCNT bundles and hydrogen chloroauric acid in an aqueous solution, activated ultrasonically and, then, drop-casted on a glass substrate. The slow drying of the drop produces a “coffee ring” pattern that is found to contain gold–MWCNT nanocomposites, accumulated mostly along the perimeter of the ring. The reaction is studied also at low-temperature, in the vacuum chamber of the Scanning Electron Microscope and is accounted for by the local melting processes that facilitate the contact between the bundle of tubes and the gold ions. Biosensing applications of the gold–MWCNT nanocomposite using their LSPR properties are demonstrated for the plasmonic detection of traces of bovine growth hormone. The sensitivity of the hybrid platform which is found to be 1 ng/ml is much better than that measuring with gold nanoparticles alone which is only 25 ng/ml

Culturing cells for life: innovative approaches in macroscopic and microfluidic cultures, with an emphasis on stem cells

In 2006, Whitesides, writing about microfluidics, said that microfluidics is in early adolescence and it is not yet clear how it will develop. Today, almost 20 years later, microfluidics became a fully developed, highly sophisticated, multidisciplinary field that had entirely honoured its early promise. Its strength stems from the knowledge and know-how, coming from multiple disciplines such as physics of fluids, engineering, and microfabrication in the beginning, followed, more recently, by cell biological research, in full bloom nowadays. In microfluidic devices, the environment of cells such as chemical and mechanical gradients can be reproduced, making biological studies even more compelling. The red thread of this review paper follows the new insights and discoveries in both traditional macro- and microfluidic cell culture brought into the cell biology field, especially in the culture of stem cells, filled with promise in the field of regenerative medicine. Microfluidic devices provide an environment that is much closer to that of in vivo cell culture than the conventional culture platforms, where large amounts of cells are cultured and the environment of individual cells cannot be distinguished. The convenience of live cell imaging, portability, and the integration of sensors to precisely, control various parameters, has expanded cell biologists’ arsenal In addition, microfluidic devices, integrated with different functionalities, that is, the automated cell culture systems, will be discussed as well

Subzero Temperature Dip-Coating of Sol-Gel Vanadium Pentoxide: Effect of the Deposition Temperature on the Film Structure, Morphology, and Electrochromic Properties

Vanadium pentoxide sol-gel prepared thin films were deposited on indium-tin-oxide (ITO) substrates by dip-coating at a subzero temperature (−10°C). The structure, morphology, and optical and electrochromic properties of dense and porous vanadium oxide films coated at low temperature were determined and compared to those of the corresponding films deposited under room-temperature conditions. The results indicated that, in the films coated at −10°C, a residual compressive stress exists that would originate from the formation of microvoids during the deposition. These microvoids are preserved during the heat treatment of the films. The microvoid morphology would favor the formation of nanostructures that would be responsible for the improved electrochromic properties of the subzero dip-coated films. Low-temperature coated films, heated at 450°C for several hours, undergo the transformation from a layered to a highly uniform nanorod structure that would be an important feature for different applications

Synthesis and characterization of tungsten trioxide powders prepared from tungstic acids

WO3 powders were prepared by the thermal decomposition of tungstic acids (WO3 nH2O, n ¼ 1/3, 1, 2). The tungstic acids were synthesized from WO4 2 aqueous solutions under a variety of conditions of pH, temperature and W(VI) concentrations. The thermal decomposition of the tungstic acids into WO3 was analysed by TG and DSC methods. Nano-sized WO3 powders with different morphological characteristics were obtained by thermal treatment of the tungstic acids at 500 8C in air atmosphere. The morphologies of WO3 powders were characterised by scanning electron microscopy and infrared absorption spectroscopy. Patterns of infrared spectra were related with distinct powder morphologies

The effect of hydrogen nanobubbles on the morphology of gold–gelatin bionanocomposite films and their optical properties

Gold–gelatin bionanocomposite films are prepared by the reduction of gold ions by sodium borohydride in an aqueous solution. It is shown that both the solution and the films on glass substrates contain entrapped hydrogen micro- and nanobubbles with diameters in the range of 200 nm–3 μm. The optical properties of gold nanoparticles in the presence of gelatin and hydrogen nanobubbles are measured and simulated by using the discrete dipole approximation method. The composite films having micro- and nanobubble inclusions have been found to be very stable. The calculated localized surface plasmon resonance band is found in agreement with the experimental band position only when the presence of hydrogen bubbles around the gold nanoparticles is taken into account. The different morphological features engendered by the presence of the bubbles in the film (gelatin receptacles for the nanoparticles, gelatin hemispheres raised by the bubbles under the surface, cavities on the surface of the film, etc) are described in detail and considered for potential applications. This work is highly relevant to the new and exciting topic of nanobubbles on surfaces and interfaces

Electrochromic Properties of Sol-Gel Prepared Hybrid Transition Metal Oxides A Short Review

This short review paper revisits the progress achieved in the last 10-15 years in the field of hybrid electrochromic materials, synthesized through sol-gel methods.During the recent decade, new avenues have been opened, exploring new concepts and particularly interesting applications of electrochromism. In this paper, we will discusssome of the new research directions in the field of electrochromism, together with novel applications of many electrochromic hybrid oxides. The most important incentive for enhanced properties of traditional materials has been the advent of nanotechnology. The discoveries in the field of synthesis of nanomaterials enabled to expand the materials and connect the morphological features of nanoparticles to the electrochromic properties at the macro level. This was possible because of the emergence of the new and more elaborate characterization methods, enabling to unveil hitherto unknown structural and morphological properties of electrochromic materials.It is important to mention the development of novel hybrid materials with significantly improved EC properties, where tungsten oxide is associated with carbonaceous materials such as MWCNT or graphene. These hybrid materials with enhanced EC properties, compared to the inorganic hybrids, will be remarkable in the future,for a series of novel applications.Retracing briefly the history of EC hybrid materials and summarizing the principal achievements will be useful not only for researchers in the field but for a wider readership as well