Showing papers on "Nanobiotechnology published in 2008"

Atomic force microscopy as a multifunctional molecular toolbox in nanobiotechnology

Abstract: With its ability to observe, manipulate and explore the functional components of the biological cell at subnanometre resolution, atomic force microscopy (AFM) has produced a wealth of new opportunities in nanobiotechnology. Evolving from an imaging technique to a multifunctional 'lab-on-a-tip', AFM-based force spectroscopy is increasingly used to study the mechanisms of molecular recognition and protein folding, and to probe the local elasticity, chemical groups and dynamics of receptor-ligand interactions in live cells. AFM cantilever arrays allow the detection of bioanalytes with picomolar sensitivity, opening new avenues for medical diagnostics and environmental monitoring. Here we review the fascinating opportunities offered by the rapid advances in AFM.

Control of enhanced Raman scattering using a DNA-based assembly process of dye-coded nanoparticles

Abstract: Enhanced Raman scattering from metal surfaces has been investigated for over 30 years1. Silver surfaces are known to produce a large effect, and this can be maximized by producing a roughened surface, which can be achieved by the aggregation of silver nanoparticles2,3,4. However, an approach to control this aggregation, in particular through the interaction of biological molecules such as DNA, has not been reported. Here we show the selective turning on of the surface enhanced resonance Raman scattering5 effect on dye-coded, DNA-functionalized, silver nanoparticles through a target-dependent, sequence-specific DNA hybridization assembly that exploits the electromagnetic enhancement mechanism for the scattering. Dye-coded nanoparticles that do not undergo hybridization experience no enhancement and hence do not give surface enhanced resonance Raman scattering. This is due to the massive difference in enhancement from nanoparticle assemblies compared with individual nanoparticles. The electromagnetic enhancement is the dominant effect and, coupled with an understanding of the surface chemistry, allows surface enhanced resonance Raman scattering nanosensors to be designed based on a natural biological recognition process. Base-pairing drives the assembly of dye-functionalized nanoparticles that have complementary DNA strands attached. This aggregation leads to a massive enhancement of the resonant Raman signal, which may prove useful for sensing applications.

Reconfigurable, braced, three- dimensional DNA nanostructures

Abstract: DNA nanotechnology makes use of the exquisite self-recognition of DNA in order to build on a molecular scale1. Although static structures may find applications in structural biology2,3,4 and computer science5, many applications in nanomedicine and nanorobotics require the additional capacity for controlled three-dimensional movement6. DNA architectures can span three dimensions4,7,8,9,10 and DNA devices are capable of movement10,11,12,13,14,15,16, but active control of well-defined three-dimensional structures has not been achieved. We demonstrate the operation of reconfigurable DNA tetrahedra whose shapes change precisely and reversibly in response to specific molecular signals. Shape changes are confirmed by gel electrophoresis and by bulk and single-molecule Forster resonance energy transfer measurements. DNA tetrahedra are natural building blocks for three-dimensional construction9; they may be synthesized rapidly with high yield of a single stereoisomer, and their triangulated architecture conveys structural stability. The introduction of shape-changing structural modules opens new avenues for the manipulation of matter on the nanometre scale.

Optical Detection of Glucose and Acetylcholine Esterase Inhibitors by H2O2‐Sensitive CdSe/ZnS Quantum Dots

Abstract: There is a growing interest in using semiconductor quantum dots (QDs) as optical labels for biosensing events. The sizecontrolled fluorescence properties of QDs, the high fluorescence quantum yields of QDs, and their stability against photobleaching makes QDs superior optical labels for multiplexed analysis of antigen–antibody complexes, nucleic acid–DNA hybrids, and other biorecognition complexes. QDs were also applied to monitor biocatalytic transformations using fluorescence resonance energy transfer (FRET) processes. FRET processes between CdSe/ZnS QDs and dye units incorporated into replicated DNA systems or into telomers were used to probe the activities of polymerase and telomerase, respectively. Similarly, FRET reactions were used to monitor the biocatalytic cleavage of peptides by hydrolytic enzymes. Alternatively, electron-transfer quenching of QDs by quinone-functionalized peptides was used to detect the activity of tyrosinase, and the hydrolytic cleavage of the quinone-modified peptide and the restoration of the fluorescence of the QDs were used to probe the activities of tyrosinase and thrombin, respectively. In all of these QD assays for monitoring enzyme activities, it is mandatory to include a quencher (energy or electron-transfer quencher) in the analyzed samples as a reporter unit. Also, for each of the enzymes, a specific assay needs to be developed. Numerous oxidases generate hydrogen peroxide (H2O2) as a product. Thus, controlling the photophysical properties of QDs by H2O2 may provide a new and versatile method to develop QD-based sensors. In fact, the biocatalyzed generation of H2O2 by oxidases was used for the development of different electrochemical biosensors, and recently for the development of optical biosensors using Au nanoparticles. Herein we demonstrate that the fluorescence of CdSe/ZnS QDs is sensitive to H2O2. This sensitivity enables the use of the QDs as H2O2 sensors and provides a versatile fluorescent reporter for the activities of oxidases and for the detection of their substrates. This utility is exemplified herein for the analysis of glucose in the presence of glucose oxidase. Furthermore, we apply the fluorescent QDs as sensors that monitor the inhibition of acetylcholine esterase (AChE). AChE hydrolyzes acetylcholine to choline and, subsequently, choline oxidase (ChOx) oxidizes choline to betaine while generating H2O2. In the presence of an inhibitor, the hydrolytic cleavage of acetycholine by AChE is perturbed, and the inhibited formation of H2O2 is reflected by the fluorescence of the QDs. In addition to the broad application of the CdSe/ ZnS for different sensing processes, we introduce the ratiometric fluorescent analysis of the different substrates. This analysis enables us to monitor the stability of the different sensors, and to correct for any precipitation events of the QDs that might cause an “apparent” decrease in the observed fluorescence intensities. We describe the use of the enzymes in solution or in immobilized forms on the QDs. Figure 1a depicts the time-dependent luminescence changes upon the reaction of mercaptoundecanoic acid (MUA) capped CdSe/ZnS QDs with H2O2 (0.4 mm). The fluorescence of the QDs decreases with time, and addition of catalase to the system, which includes H2O2, blocks the decrease in the fluorescence, implying that H2O2 is, indeed, the component affecting the fluorescence. Figure 1b shows the fluorescence quenching of the QDs upon interaction with different concentrations of H2O2 for a fixed time interval of 10 minutes. Although the precise mechanism that stimulates the decrease in the fluorescence of the QDs is not fully

New aspects of nanopharmaceutical delivery systems.

Abstract: Nanobiotechnology, involving biological systems manufactured at the molecular level, is a multidisciplinary field that has fostered the development of nanoscaled pharmaceutical delivery devices. Micelles, liposomes, solid lipid nanoparticles, polymeric nanoparticles, functionalized nanoparticles, nanocrystals, cyclodextrins, dendrimers, nanotubes and metallic nanoparticles have been used as strategies to deliver conventional pharmaceuticals or substances such as peptides, recombinant proteins, vaccines and nucleotides. Nanoparticles and other colloidal pharmaceutical delivery systems modify many physicochemical properties, thus resulting in changes in the body distribution and other pharmacological processes. These changes can lead to pharmaceutical delivery at specific sites and reduce side effects. Therefore, nanoparticles can improve the therapeutic efficiency, being excellent carriers for biological molecules, including enzymes, recombinant proteins and nucleic acid. This review discusses different pharmaceutical carrier systems, and their potential and limitations in the field of pharmaceutical technology. Products with these technologies which have been approved by the FDA in different clinical phases and which are on the market will be also discussed.

The Handbook of Nanomedicine

Abstract: 1. Introduction 2. Nanotechnologies 3. Nanotechnologies for Basic Research Relevant to Medicine 4. Nanomolecular Diagnostics 5. Nanopharmaceuticals 6. Role of Nanotechnology in Biological Therapies 7. Nanodevices & Techniques for Clinical Applications 8. Nanooncology 9. Nanoneurology 10. Nanocardiology 11. Nanopulmonology 12. Nanoorthopedics 13. Nanoophthalmology 14. Nanomicrobiology 15. Miscellaneous Healthcare Applications of Nanobiotechnology 16. Nanobiotechnology and Personalized Medicine 17. Nanotoxicology 18. Ethical and Regulatory Aspects of Nanomedicine 19. Research and Future of Nanomedicine 20. References

Fundamentals of Nanotechnology

Abstract: Perspectives Introduction Perspectives of Nanotechnology The Business of Nanotechnology Education and Workforce Development Buildings for Nanotech National and International In-frastructure Nanotechnology Products Nanometrology: Standards and Nanomanufacturing The Transition, the Need Nanometrology and Uncertainty Quantum Metrology Nanometrology Tools Nanometrology and Nanomanufacturing Standards Nanomanufacturing and Molecular Assembly Electromagnetic Engineering Nanoelectronics Electronics and Nanoelectronics Microelectronics Nanoscale Electronics Nano-optics Introduction to Optics The Surface Plasmon Quantum Dots Near-Field Microscopies Nanophotonics Nanomagnetism Introduction Characteristics of Nanomagnetic Systems Magnetism in Reduced Dimensional Systems Physical Properties of Magnetic Nanostructures Recent Progress in Nanoscale Sample Preparation Nanomagnetism Applications Mechanical Nanoengineering Nanomechanics Introduction Three-Atom Chain Lattice Mechanics Stress and Strain Linear Elasticity Relations Molecular Dynamics Structure and Mechanical Properties of Carbon Nanotubes Nanomechanical Measurement Techniques and Applications Nano-Microelectromechanical Systems (NEMS/MEMS) Nanostructure and Nanocomposite Thin Films Introduction Classification of Nanostructured, Nanocomposite Tribological Coatings Background of Nanostructured Super-Hard Coatings New Directions for Nanostructured Super-Tough Coatings Processing Techniques and Principles General Considerations and Practical Aspects of Sputtering Deposition Applications of Thin Films Technological Applications of Thin Films Unbalanced Magnetron Sputtering of Ti-Al-Si-N Coatings Unbalanced Magnetron Sputtering of Ti-Si-B-C-N Coatings Pulsed Closed Field Unbalanced Magnetron Sputtering of Cr-Al-N Coatings Chemical Nanoengineering Nanocatalysis Introduction to Catalytic and Nanocatalytic Materials Fundamentals of Catalysis Synthesis Catalyst Characterization Nanocomposites and Fibers Nanocomposites and Fibers Physical and Chemical Properties of Materials Natural Nanocomposites Carbon Fibers and Nanotubes Organic Polymer Nanocomposites Metal and Ceramic Nanocomposites Clay Nanocomposite Materials Biological and Environmental Nanoengineering Nanobiotechnology Introduction to Nanobiotechnology The Biological Immune System Using Antibodies in Biosensors: Immunoassays Cantilevers as Nano-Biosensors Micro- and Nanosensors and Applications Optical Nanosensors Nanotechnology for Manipulation of Biomolecules Biomimetics The Bio Sciences and Technologies Biomimetic Design of Molecules Biomimetic Nanomaterials Biomimetic Nanoengineering Medical Nanotechnology Introduction to Medical Nanotechnology Nanoparticles and Nanoencapsulation for Medical Applications Guiding and Stimulating Tissue Function and Growth Environmental Nanotechnology The Environment (and Technology) Water and Soil Quality, Monitoring, and Mitigation Air Quality, Monitoring, and Mitigation Energy

The mathematical engines of nanomedicine.

Abstract: I am with those that firmly believe that nanotechnology will help conquer historical bottlenecks in the fight against disease, by providing tools for the detection of pathologies, and for the exquisitely precise delivery of therapy and prevention agents. Success in these quests requires a tight, interweaving integration of multiple disciplines with the multifaceted spectrum of sciences we call “nanotechnology”. Mathematics is a necessary component of this integration, and plays four fundamental roles. It is a compass that guides us through unbearable complexity to discover hidden treasures. It leads to discoveries that force us to reluctantly contradict our own dogmas and, by doing so, advances our efforts against disease. It is a cauldron of methodological innovation that yields potions for multidisciplinary transformations. It is an essential part of the very definition of nanotechnology. This Essay is dedicated to the articulation of these four theses. It is not a review of the many important contributions that have joined mathematics and nanotechnology – it is just a statement of my personal opinions.

Synthesis of Glutamate-Zinc-Aluminium-Layered Double Hydroxide Nanobiocomposites and Cell Viability Study

Abstract: A layered compound of zinc-aluminium layered double hydroxide (LDH) to be used as a host for a guest amino acid, gluta-mate was synthesized. Different parameters were used and optimized to form amino acid-intercalated pure phase materials. The resulting Bio-Inorganic Nanohybrid (BINH) was chosen for further characterization. BINH exhibits the glutamate to be in vertical or perpendicular orientation to the inorganic layer. Cytotoxicty test indicates that the IC 50 value was observed at 3.125
g/ml. Results from this study will be used in the development of a new delivery system for therapeutic agents comprising amino acids or peptides. Key Words: Nanobiotechnology, glutamate, layered double hydroxide, bio-inorganic nanohybrid. INTRODUCTION One of the targeted research areas for scientists worldwide in this new millennium is in the field of nanobiotechnology. Intense research has been conducted to investigate the possibilities of in-corporating the field of nanotechnology with molecular biology. It is anticipated that this new field would revolutionize areas related to biosensors, medical diagnostics, biomechanics and bioelectronics [1, 2]. Nanobiotechnology is based on nanomaterials and technology involving molecular biology techniques. This involves the exploita-tion of various molecular modified nanomaterial components such as dendrimer, nanotube, and nanoparticles. This area of research can be applied significantly for medical examination and treatment, drug delivery, biomimetic sensors, gene therapy, and immunologi-cal diagnosis [3-5]. Although nanobiotechnology is still in its in-fancy stage of development, it is moving at a very fast pace as indi-cated by the establishment of many nanotechnology centers world-wide. In 2005, a report in

Bio-inorganic hybrid nanomaterials : strategies, syntheses, characterization and appliacations

Abstract: Bio-mineralization: Bio-mineral Inspired Materials Biopolymer-Silica Nanocomposites Bio-nanohybrids Based on Silica and Biological Molecules Porous Membranes for Applications in Bionanotechnology Hydroxyapatite-based Bionanocomposites DNA-based Nanohybrids Bio-inorganic Hybrids Based on Enzymes Hybrid Nanocomposites at the Biology/Electronics Interphase Development of Bioactive Organic-inorganic Hybrids with High Flexibility Development and Medical Application of Cartilage-, Nerve- and Ligament-regeneration Materials by Controlled Organic-inorganic Interaction Polymer-inorganic Nanohybrids as Bio-inspired Materials Biomaterial Arrays on Inorganic Surfaces for Sensor Applications Fabrication of Novel Bio-inorganic Nanohybrid Materials via Supramolecular Approaches Proteins in Inorganic Mesoporous Materials Nano- and Meso-scale Bio-inorganic Hybrid Materials Functional Capsules of Bio-inorganic Nanohybrids DNA-engineering on Inorganic Nanoparticles Halloysite Clay Nanotubules as a Container for Biomolecules

Nanobiotechnology and biosensor research

Abstract: Nanobiotechnology is defined as an interdisciplinary field of science that studies the application of fine-sized biological objects (of nanoscale, 1–100 nm) to design the devices and systems of the same size that utilize for new purposes the unusual, known, or previously unknown effects. Analysis demonstrates that the final goals, approaches, solution methods, and applications of nanostructures and biological sensors have much in common. This brief review attempts to systematize a number of the available data and pick out an organic connection of the new research direction with the field of biosensor technology, which have reached the level of sustainable development.

Novel coating of micro-nanoprojection patches for targeted vaccine delivery to skin

Abstract: This study presents a simple, versatile and controllable method to achieve uniform coating on very small and densely packed micro-nanoprojections for epidermal immunotherapeutic delivery.

DNA molecules on GaP (100) surfaces: spectroscopic characterization and biospecificity assessment.

Abstract: DNA-modified surfaces have been the subject of considerable research activity in the field of bionanotechnology. Such surfaces can be incorporated into novel diagnostic devices that utilize sequencing and gene mapping technologies. 3] For example, the use of DNAbased sensors shows promise for rapid, economical and accurate detection of genetic diseases. In such sensor devices it is very important to have a robust and reproducible packing of DNA molecules. Different research groups have explored the absorption of biomolecules and the integration of biological systems on inorganic materials such as gold and silicon. Recently, there has been an interest in extending such studies to III–V semiconductor substrates. Gallium phosphide (GaP) is an attractive semiconductor material due to its usage in charge storage devices and low-noise detection photodiodes. This material offers promise for the fabrication of novel biosensors. Our previous work demonstrated that GaP ACHTUNGTRENNUNG(100) remains stable after surface functionalization with well-parked adlayers and high molecular coverages. Herein, we describe the covalent functionalization and characterization of H-doped GaP ACHTUNGTRENNUNG(100) with modified DNA strands. We demonstrate that photochemical functionalization with undecylenic acid (UDA) can modify GaP substrates and that the terminal carboxylic acid groups can be used for the successful immobilzation of biomolecules (Scheme 1). In our approach, we control the orientation of modified DNAs by reacting the carboxylic acid-terminated GaP ACHTUNGTRENNUNG(100) surfaces with a mixture of amine-terminated ssDNA and a spacer, hexylamine (HA). We also confirm the bioactivity of biotin-modified DNA by the use of streptavidin-modified nanoparticles and Cy3-labeled streptavidin. The following techniques are used to complete the physical characterization of the surfaces: water contact angle (WCA), atomic force microscopy (AFM), Fourier transform infrared reflectance absorbance spectroscopy (FT–IRRAS). Prior to any spectroscopic analysis each modified surface is evaluated using WCA and AFM. The data, summarized in the Supporting Information, follows the expected hydrophicilicity trend due to the nature of the end groups. In addition, no major changes in roughness are observed after each treatment. Initial spectroscopic analysis of the modified surfaces by FT–IRRAS spectroscopy provides us with information about the adsorbates’ orientation on the GaP surface. The FT–IRRAS vibrations for H-doped, Br-modified DNA/HA, biotin-modified DNA/HA and biotin-modified DNA/HA/streptavidin nanoparticles GaP ACHTUNGTRENNUNG(100) steps are shown in Figure 1. We place a Br-label at the 5’ end of the DNA so that we can use it as a way to prove that molecules are on the surface by X-ray photoelectron spectroscopy (XPS). The FT–IRRAS spectrum of H-doped GaP ACHTUNGTRENNUNG(100) does not show any peaks in the low and high frequency regions, as one would expect to be the case immedi[a] Dr. R. Flores-Perez, Prof. A. Ivanisevic Department of Chemistry Weldon School of Biomedical Engineering, Purdue University 206 S. Martin Jischke Drive, West Lafayette, IN 47907 (USA) Fax: (+1)7654961459 E-mail : albena@purdue.edu [b] Dr. D. Y. Zemlyanov Birck Nanotechnology Center Purdue University, West Lafayette, IN 47907 (USA) Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/cphc.200800166. Scheme 1. Surface coupling chemistry used to modify GaP with DNA molecules.

From liposomes of the 1970s to 21st century nanobiotechnology

Abstract: The review is devoted to actual problems of studying liposomes and other lipid nanoparticles that, being loaded with active substances, can be widely used in biomedical applications.

Optoelectronic Signatures of Biomolecules Including Hybrid Nanostructure-DNA Ensembles

Abstract: Biological macromolecules such as DNA, proteins, and polysaccharides often display unique absorptive signatures in the THz region, useful in their identification and imaging through Raman and Fourier transform transmission spectroscopy. The optoelectronic properties of nanostructure-DNA complexes immobilized on transparent, semi-rigid substrates such as polymethyl methacrylate (PMMA) have been studied. By chemically modifying the PMMA substrates with amine terminal groups and using suitable linking agents, amine terminated DNA can be localized on these substrates. THz Fourier transform transmission spectroscopy was used to detect low-frequency vibrational modes (10-25 cm-1) within single- and double-stranded DNA molecules immobilized on PMMA attached to TiO2 nanoparticles. Additionally, DNA strands end terminated with TiO2 nanoparticles are used in this study to cleave the DNA at guanine (G) rich sites due to trapping of photo-induced charge carriers from the TiO2 at these sites. Theoretical modeling of charge transport through DNA via polaron transport is discussed in detail. By examining the vibrational modes of DNA, as well as the transport of charge in DNA this study underlies potential applications involving DNA micro-arrays, DNA-based sensors, and DNA-based THz devices.

The Detection and Characterization of Ions, DNA, and Proteins Using Nanometer‐Scale Pores

Abstract: Protein ion channels are nanometer-scale pores that are central to many biological processes, including the sensing of a wide variety of molecules. They have also demonstrated potential for use in the sensitive and selective detection of ions, the characterization of polynucleotides and toxins as well as the screening of therapeutic agents against lethal anthrax proteins. Further advances in materials engineering, theory, and signal processing are needed to enable practical applications based on biological or synthetic nanopores. Keywords: α-haemolysin; α-hemolysin; analyte detection; anthrax; biosensor; biotechnology; DNA; edema factor; lethal factor; nanobiotechnology; nanopore; polynucleotide; polymer transport; protective antigen; protein ion channel; protein structure function; stochastic sensor

DNA Nanotechnology: Bacteria as factories

Abstract: Producing large quantities of designer DNA nanostructures at low cost has been a long-standing challenge in nanobiotechnology. It is now possible with the aid of bacteria.

Nanobiotechnology: putting cobalt on the menu.

Abstract: Nanocrystals of magnetite in magnetic bacteria are known for their high chemical purity, but recent work shows they can be doped with cobalt. This finding could pave the way for the biosynthesis of magnetically tailored nanoparticles.

The Current State of Bionanotechnology

Abstract: Bionanotechnology is a combination of three terms: “bios” meaning “life,” “nano” (origin in Greek) meaning “dwarf,” and “technologia” (origin in Greek—comprised of “techne” meaning “craft,” and “logia” meaning “saying”), which is a broad term dealing with the use and knowledge of humanity’s tools and crafts. Biomolecular Nanotechnology—or Bionanotechnology—is a term coined for the area of study where nanotechnology has applications in the field of biology and medical sciences. One can also say that “Bionanotechnology” is derived by the combination of two terms: “nanotechnology,” and “biotechnology.”