Biosensors are nowadays a powerful tool to enable the detection of specific biological interactions and to evaluate the concentration dependence in the response. A biosensor usually consists of three different parts: the sample to be measured, the transducer and the electronic system that amplifies the signal, analyzes the data and brings a result to the final user. When the analyte interacts with the bioreceptor, the transducer sends a signal that is processed by the electronics. All this process occurs in a efficient, quick, cheap, simple and specific way. Optical biosensors are the most powerful ones for investigating processes at the solid/liquid interface. Among them the grating coupler is immune to electromagnetic interferences, pushes the sensitivity to levels even higher than other techniques and allows for the direct monitoring of macromolecular adsorption. Taking advantage of the last advances in nanotechnology, this book studies the versatility of an Optical Grating Coupler Biosensor. The design of new grating sensor chips is investigated, a new calibration technique for the sensors is proposed and different biomedical scenarios are tested.
Biomedical electronics and instruments, equipment, diagnostic & detection tools success based on the success of high sensitive biosensors invention and development. Biosensors are the active electronic, semiconductor electronics, optoelectronics or other technologies related devices which sense biological signal from membrane in the form of antibodies, antigens, bacteria''s, viruses, glucose, oxygen, pH etc called signal/stimuli/receptor at the contact of membrane and biosensor with transducer along with biological sensing element called “ion-electron-interfacing” from where signal convert into detectable electrical signals through transduction principles and measured at computerized electronic signal processing system. This monograph strongly related only about optoelectronic biosensor, in which discussed investigated evanescent wave optical fiber biosensor is one of the strong light carry biological information sensation and high speed detection sensor. Book deal with review, research and fundamental modeling.
Optical fibre-based devices (e.g. fibre gratings) play an important role in the optical communications and sensing industry. One type of fibre grating, the long-period grating (LPG),is becoming more and more popular as a simple and versatile component for a number of applications in optical engineering. Long period grating is obtained by introducing a periodic refractive index modulation in the core of an optical fibre. The phase matching condition causes light to couple from core mode to forward propagating cladding mode. These cladding modes attenuate rapidly on propagation and thus resulting in distinct resonance bands in transmission spectrum. The sensitivity of LPGs to various external perturbations and their ability to manipulate selectively light propagating in optical fibres make them well-suited to creating fibre-based devices. LPGs can be used in various applications, for example as gain equalisers for erbium-doped fibre amplifiers, as channel routers in optical add-drop multiplexers and as sensors. LPGs are typically fabricated by exposing photosensitive optical fibre to ultraviolet light.
Laser and fiber optics applications have opened some new possibilities in medicine and dentistry. Advanced diagnostic techniques and laser-based therapeutic techniques have been developed. Here, we have introduced some new techniques for medical and dental applications using lasers and modern optics. The main task of our work is biomedical applications of lasers. A new approach based on image holography is applied for dental deformation measurement. The advantages of this technique compare to existing techniques are shown. Imaging and deformation measurement of in-plane and out-plane deformations is performed using the interferometric fringes. Interferograms obtained by holographic-based techniques are shown. The imaging technique, based on optical implementation of moments as to our best knowledge, is introduced for the first time in biomedical applications. In addition to this Fourier Transform of far Field diffraction technique is introduced as well. A simple and robust technique based on the Moire phenomenon is applied. Using Moire fringes generated by two gratings and their projection on the object to be analyzed, contours and 3-D information are obtained.
In recent past magnetic nanoparticles have been explored for a number of biomedical applications due to their superparamagnetic moment with high magnetic saturation value. For the various biomedical applications, magnetic nanoparticles are require to being monodispersed so that the individual nanoparticle has almost identical physico-chemical properties for biodistribution, bioelimination and contrast imaging potential. Further, the surface functionalization/modification of magnetic nanoparticles ultimately facilitates the enzyme immobilization, remediation of heavy metal ions, drug delivery and hyperthermia applications. The essential goal of this work is to evaluate the recent advances of magnetic nanoparticles for different biomedical applications.
Recently, one-dimensional nanostructures that include fibers, wires, rods, belts and tubes have attracted rapidly growing interest due to their fascinating properties and unique applications. Among them, electrospinning is a highly versatile technique to prepare continuous fibers with diameters of the order of nanometers. It is the most famous technique for the production of high aspect ratio nanofibers. The remarkable high aspect ratio and high porosity bring electrospun nanofibers highly attractive to various nanotechnological applications such as filteration, sensors, protective textile, catalysis, wound dressing, drug delivery, scaffolds in tissue engineering, and so on. This book, therefore, addresses a collective summary of the recent progress in developments of the electrospun ultrafine polyamide-6 nanofibers preparation, characterization and their applications. Information of those polymers together with their processing conditions for electrospinning of ultrafine nanofibers has been summarized. We are anticipating that this book certainly drive the researchers for developing more intensive investigation for exploring in many technological areas.
With the advancement in material chemistry, a range of novel materials have been introduced to healthcare, among them, silica has received a great attention due to its high biological compatibility. Furthermore, it?s composites with other materials have opens up realm of novel applications. This book embodies the appreciation of silica based metals nanocomposites by presenting their synthesis and application for very important sensing and healthcare sector. The entire material is presented in two sections divided in 10 chapters. The synthesis of Au-poly (dimethylsiloxane) nanocomposites by in-situ synthesis and galvanic replacement approach, characterization and functionalization for biosensing application using human serum albumin as a model system are described in Section A. While Section B deals with the synthesis, characterization and antimicrobial activity of silica-silver nanocomposites against both Gram positive and Gram negative bacteria. The most exciting and unique aspect of the book is that the utilization of these nanocomposites not only enhances the biosensing capabilities, but also brings out newer approaches in healthcare.
This book presents several theoretical, numerical and experimental studies in the field of plasmonics, which I carried out during my PhD. One basic problem in plasmonics is the study of optical Bloch modes of planar arrays of metallic nanostructures. Here a new finite-elements-based numerical approach for the modal analysis of such structures is described. Then I present a thorough investigation of the optical properties of a well-known plasmonic crystal, which is the 1-D lamellar grating. The focus here is the possible use of this structure as a light trapping device for photovoltaics applications. Another treated topic is plasmonic nanofocusing: an experiment involving metal-coated dielectric wedges is discussed. A similar structure is then studied for the implementation in an optoelectronic biosensor based on a high electron mobility phototransistor. Finally a class of particular nanostructures is addressed, termed as plasmonic vortex lenses, constituted by spiral and circular grooves on a gold surface, which are able to impress an arbitrary orbital angular momentum to the propagating surface plasmons.
Enzyme electrodes are biochemical transducers. They function by converting biochemical reactions into electrochemical processes. This functionality could potentially give rise to a new generation of implantable medical devices such as biofuel cells and biosensors. The main aim of this study was to fabricate and characterise enzyme electrodes for potential use in these applications. The approach involved testing various materials such as different types of enzyme, polymeric electron transfer mediators, enzyme entrapment materials, conductive supports and matrices and biocompatible polymers. Various enzyme immobilisation methods were used and various polymeric electron transfer mediators were fabricated and tested. The investigation was based primarily on electrochemical techniques. The materials and immobilisation techniques presented could potentially be used to improve future enzyme electrodes. This may be achieved through the novel use of biocompatible and biomimicking polymers, through simple biofuel cell fabrication and with the use of multi analyte biosensors developed during this investigation.
Nowadays, many researchers have focused on the preparation and characterization of new biomaterials which could be used for the bone tissue reconstruction without the problems of traditional metallic and organic materials. Consisting of two main chapters, this study gives the information about bioactive glass-ceramics and hydroxyapatite which are predestined materials for biomedical applications, in particular in orthopedic and dental implants, due to their excellent bioactivity and proved biocompatibility. The preparation method and characterization of sol-gel derived BSA-bioactive glass-ceramic nanocomposite is discussed in the first chapter and the second chapter presents a detailed discussion of the synthesis and characterization of hydroxyapatite-chitosan nanocomposite.
This book describes theoretical and modeling study of optical waveguide design, in straight and branched waveguide for ion-exchanged and silicon based materials. Physical parameters involved in the fabrication have been modeled to produce the highest possible evanescent field based on the material that they are using. Apart from that, optical properties such as polarization, beam spot size and wavelength are also studied to monitor their effects on the evanescent field. The compilation of research papers in this book can be used to fabricate an integrated waveguide with optimized condition. These simulation results demonstrate, that evanescent wave based, integrated optical devices for trapping are feasible and can be optimized; paving the way for real-life application devices to be realized.
Emergence of multi-resistant organisms (MROs) leads to ineffective treatment with the currently available medications which pose a great threat to public health and food technology sectors. In this regard, there is an urgent need to strengthen the present therapies or to look over for other prospective alternatives such as use of “metal nanocomposites” and “drug loaded polymeric nanofibers”. Herein, we report synthesis of silver-zinc oxide (Ag-ZnO) nanocomposites and drug loaded chitosan-PEO (Polyethylene oxide) nanofibers with excellent antibacterial activity. Formulation of such nanocomposites and nanofibers hold great promise towards development of antimicrobial packages and for various biomedical applications.
Biometric systems are computer-assisted identity recognition systems that can identify people by assessing their physical and biological characteristics. With the help of this technology, the processes that require confidentiality are performed without errors, without unauthorized copying and without the need for another person to control the access, because the physical characteristics that are taken into consideration during the identity recognition process are different in each person. Fingerprint recognition, hand geometry recognition, palm recognition, iris/retina recognition, face recognition, voice analysis, signature analysis are among the most common methods for recognition purposes. Each of these systems have advantages as well as some drawbacks when the sectors in which they are going to provide services are considered. The convenience of a system is determined with the assessment of some factors such as its price, error rate, sensitivity level to the environment and being user-friendly. After the continuous researches, these methods have been optimized with the developing technology day by day, and the costs have been reduced.
The past decade has witnessed the fastest growing of biomedical optics research in history. Optical coherence tomography (OCT) is one of the most exciting inventions in biomedical optics. This dissertation represented my Ph.D. research work on ophthalmic OCT under the mentoring of Dr. Zhongping Chen at Beckman Laser Institute & medical clinic of University of California, Irvine (BLIMC-UCI). My other academic advisors included Dr. Bruce Tromberg, Dr. Anthony Durkin, Dr. Ron Kurtz, and Dr. Barry Kupperman. The in vivo spectral Doppler OCT imaging technology developed to image dynamic, pulsatile retinal blood vessels was highlighted in this dissertation. Some technical details of the ophthalmic OCT imaging system I developed at BLIMC-UCI were discussed. Some collaborated ophthalmic research work such as screening retina transplants and monitoring subsurface femtosecond laser photo-disruption on anterior segment of human eye for Glaucoma treatment were also presented. I wish the publication of this dissertation will not only promote scientific knowledge, but also stimulate interest of readers in developing more OCT applications.