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Applications of Atomic Force Microscopy
Atomic Force Microscopy (AFM) is a versatile tool used for detailed surface imaging and analysis. It offers high-resolution imaging for both dry and liquid samples, making it invaluable for biological studies, nucleic acid research, and mechanical property analysis. AFM’s applications range from real-time cell biology observations to nanofabrication and defect detection in materials, highlighting its…
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Atomic Force Microscopy
Introduction to Atomic Force Microscopy (AFM) Atomic force microscopy (AFM) is a cutting-edge member of the microscopic techniques known collectively as scanning probe microscopy (SPM). The underlying principles of SPM are markedly distinct from those of light and electron microscopy. SPM methods are used to study the surface properties of materials by scanning an extremely fine probe over the specimen surface. This relatively recent technique emerged in 1981 when Gerd Binnig and Heinrich Rohrer developed the first working SPM, specifically the scanning tunneling microscope (STM). Fundamentals of Scanning Probe Microscopy (SPM) Atomic Force Microscope (AFM) Modes of AFM Operation Imaging Modes Force Mode AFM/Force Spectroscopy Resolution of AFM Advantages of AFM Conclusion Atomic force microscopy (AFM) represents a significant advancement in microscopic techniques, enabling detailed surface analysis and manipulation at the nanoscale. With its versatile operation modes and superior resolution capabilities, AFM stands out as an indispensable tool in scientific research, offering unique advantages over traditional electron microscopy, especially in the study of soft and biological samples.
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Transmission Electron Microscope (TEM)
The transmission electron microscope (TEM) is a groundbreaking tool in electron microscopy, first developed by Knoll and Ruska in the 1930s. It utilizes a focused electron beam to produce highly detailed images of thin specimens by detecting electrons transmitted through them. TEMs employ thermionic emission guns and can accelerate electrons to high potentials, enabling high-resolution…
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Scanning Electron Microscope (SEM)
The scanning electron microscope (SEM) is a revolutionary imaging tool that allows for detailed observation of specimen surfaces at a microscopic level. Utilizing a focused beam of electrons, SEMs generate high-resolution images that reveal fine surface structures. The electron gun and magnetic lenses direct and focus the electrons onto the specimen, which is then scanned…
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Electron Microscopy
In 1924, Louis de Broglie theorized that particles possess wave-like properties, a concept later confirmed by electron diffraction experiments. This breakthrough laid the foundation for electron microscopy. The de Broglie equation describes the relationship between a particle’s wavelength and its momentum, highlighting that electrons accelerated in a microscope can achieve extremely short wavelengths, crucial for…
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Multiphoton Laser Scanning Microscopy
Multiphoton microscopy utilizes the simultaneous absorption of two photons to excite fluorophores, enabling imaging with longer wavelength light. The process necessitates intense light sources, such as pulsed infrared lasers, to achieve sufficient photon density. Notably, this technique allows deeper tissue imaging, as biological specimens poorly absorb near-infrared radiation compared to UV and blue-green radiation. Additionally,…
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CLSM -Confocal Laser Scanning Microscopy
Confocal Laser Scanning Microscopy (CLSM) enables high-resolution imaging of biological specimens by focusing on thin layers within the sample. Utilizing lasers, pinhole apertures, and raster scanning, CLSM provides sharp, detailed images and facilitates three-dimensional reconstruction. This technique offers significant advantages in the precise localization and visualization of cellular structures, paving the way for advancements in…
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Fluorescence Microscopy
Fluorescence microscopy is a pivotal technique in biological research, allowing the visualization of cellular structures and functions with enhanced contrast and resolution. By using fluorescent probes, GFP tagging, and advanced methods like TIRF, researchers can gain detailed insights into cellular processes. This study note covers the principles, types, and applications of fluorescence microscopy, highlighting its…
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Microscopy
Light microscopy plays a crucial role in biological research, offering a means to visualize microscopic objects and macromolecules. By leveraging the principles of geometrical optics, various forms of microscopy, such as bright-field, dark-field, and phase contrast, enhance image contrast and resolution in unique ways. This study note delves into the fundamentals of light microscopy, including…
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Fluorescence-activated Cell Sorting (FACS)
Fluorescence-activated cell sorting (FACS) is a powerful technique used to separate and purify cells or particles based on their fluorescence properties. By using fluorescently-labeled probes that bind to specific cellular or particle markers, such as proteins or nucleic acids, the FACS system measures the fluorescence of each individual cell or particle, allowing for identification and…
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Liquid Chromatography
Liquid chromatography (LC) is a powerful separation technique used in many fields of science, including biology. LC separates a mixture of compounds by passing it through a stationary phase and a mobile phase. The compounds in the mixture interact differently with the two phases, leading to their separation based on their relative affinities for each…
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DNA Sequencing
Introduction: Sanger Sequencing: Next-Generation Sequencing (NGS): Nanopore Sequencing: Conclusion:
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Sanger Sequencing
Introduction: Principle of Sanger Sequencing: Steps of Sanger Sequencing: Advantages of Sanger Sequencing: Limitations of Sanger Sequencing: Applications of Sanger Sequencing: Conclusion:
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Next-Generation Sequencing (NGS)
Introduction: Illumina Sequencing: Roche 454 Sequencing: Ion Torrent Sequencing: Workflow: Applications: Conclusion:
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DNA Cloning
Introduction: Restriction Enzyme Cloning: PCR Cloning: Gene Synthesis: Conclusion:
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Restriction Enzymes
Introduction: Restriction Enzymes, also known as restriction endonucleases, are enzymes found in bacteria that play a crucial role in their defense mechanism. These enzymes recognize specific DNA sequences and cut the DNA at those sites, resulting in the restriction of foreign DNA from entering the bacterium. Restriction enzymes have become valuable tools in modern molecular…
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Restriction Mapping
Introduction Principles of Restriction Mapping Methods of Restriction Mapping Applications of Restriction Mapping Conclusion
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Polymerase Chain Reaction (PCR)
Introduction Principles of PCR Components of PCR PCR Applications Types of PCR Limitations of PCR Conclusion
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Real-Time PCR
Introduction: Real-Time PCR is a powerful and versatile tool used in molecular biology to quantify the amount of specific DNA or RNA in a sample. This technique enables quantification of nucleic acids in real-time by monitoring the accumulation of fluorescence generated during the extension phase of the PCR reaction. Principle: Real-Time PCR is based on…
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FLIP (Fluorescence Loss in Photobleaching)
Discover the power of Fluorescence Loss in Photobleaching (FLIP), a technique used to investigate molecular dynamics within cells. Explore its applications in protein and membrane dynamics, protein-protein interactions, intracellular transport, and subcellular compartmentalization. FLIP provides valuable spatial and temporal information, allowing researchers to study biological processes in their natural state. Embrace the versatility of FLIP…
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FRAP (Fluorescence Recovery After Photobleaching)
Fluorescence Recovery After Photobleaching (FRAP) is a powerful technique widely employed in the study of biomolecules within biological systems. By selectively bleaching a small region of a sample and monitoring the subsequent fluorescence recovery, FRAP enables the investigation of molecular mobility. Its applications encompass protein dynamics, intracellular organelle movements, cytoskeleton organization, membrane dynamics, intracellular transport,…
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Gene Therapy: A study note
Gene therapy is a groundbreaking medical approach that holds tremendous potential for revolutionizing disease treatment. By altering the genetic material within cells, gene therapy aims to correct abnormal genes or introduce therapeutic genes to combat a wide range of conditions. This study note provides a comprehensive overview of gene therapy, exploring its principles, techniques, applications,…
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DNA Microarray Technique
DNA microarray is a powerful technique used to study gene expression levels in a high-throughput manner. It involves hybridizing labeled target sequences to DNA probes on a microarray, allowing researchers to detect and quantify specific nucleic acid sequences. This study note explores the principles, procedure, applications, and limitations of DNA microarray, highlighting its role in…
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Gel Electrophoresis
Gel electrophoresis is a widely used technique in molecular biology for separating and analyzing DNA, RNA, and proteins. It plays a crucial role in various applications such as DNA analysis, protein characterization, and clinical diagnostics. This study note provides an in-depth understanding of the principles, procedure, and applications of gel electrophoresis, making it a valuable…
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ChIP (Chromatin Immunoprecipitation)
ChIP (Chromatin Immunoprecipitation) is a powerful molecular biology technique used to study protein-DNA interactions in cells. This article explores the principles, procedure, applications, and limitations of ChIP, providing insights into its significance in gene expression regulation and chromatin structure. Discover how ChIP has revolutionized research in genetics, epigenetics, and cancer research, while also exploring newer…
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RIA (Radioimmunoassay)
Discover the powerful technique of Radioimmunoassay (RIA) used in immunological and biomedical research. Explore the principles, types, reagents, and procedure involved in RIA. Uncover the advantages of its sensitivity, specificity, and versatility, while acknowledging limitations such as radiation hazards. Delve into the wide-ranging applications of RIA in medical research, diagnostics, and environmental monitoring. Embrace RIA…
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Spectroscopy and Beer-Lambert’s Law
Spectroscopy, a fascinating scientific technique, delves into the captivating interaction between matter and electromagnetic radiation. By analyzing how substances interact with light at different wavelengths, spectroscopy provides crucial insights into the composition, structure, and behavior of materials. One of the fundamental principles in spectroscopy is the Beer-Lambert’s Law, a cornerstone in quantitative analysis. This law…
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Retinoblastoma
Retinoblastoma is a rare type of cancer that affects the retina of the eye and is caused by mutations in the retinoblastoma (RB) gene. The RB gene plays a critical role in the regulation of cell growth and division, acting as a tumor suppressor by inhibiting the activity of other proteins that are important for…
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DNA Fingerprinting
The article discusses DNA fingerprinting, a technique used to identify individuals based on their unique DNA pattern. It explains the principle of DNA fingerprinting, the methods used, and its various applications such as criminal investigations, paternity testing, and medical research. The advantages and disadvantages of DNA fingerprinting are also discussed along with the ethical and…
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Lac Operon- Gene Regulation in Bacteria
The lac operon, found in E. coli bacteria, is a remarkable genetic system that controls the metabolism of lactose, a sugar commonly present in milk. This operon comprises three crucial structural genes: lacZ, lacY, and lacA, responsible for encoding the essential enzymes needed to break down lactose into glucose and galactose. Its significance in the…
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DNA Footprinting
The DNA footprinting technique is used to study the interactions between DNA and proteins. This allows researchers to identify which regions of DNA are bound by specific proteins and how they interact with DNA. DNA footprinting has various methods like chemical, thermal, and electrophoretic mobility shift assays, which are used to map protein-DNA interactions, study…
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RFLP (Restriction Fragment Length Polymorphism)
The excerpt introduces RFLP, a molecular biology method for detecting DNA sequence variations. It explains the principle of restriction enzymes cutting specific DNA sequences and generating restriction fragments. The procedure involves DNA isolation, digestion, gel electrophoresis, and hybridization with labeled probes. RFLP’s applications span genetics, forensic science, and medical diagnostics. Despite its replacement by newer…
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Electrophoretic Mobility Shift Assay: EMSA
The text describes Electrophoretic Mobility Shift Assay (EMSA), a molecular biology technique used to study protein-DNA interactions. EMSA is based on the principle that proteins can bind to specific regions of DNA and alter its conformation, affecting the mobility of the DNA in an electric field. This technique is used to study transcription regulation, DNA…
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Random Amplified Polymorphic DNA (RAPD)
Introduction: Principles of RAPD: Procedure: RAPD analysis involves the following steps: Applications: Limitations: Conclusion:
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Nuclear Magnetic Resonance (NMR)
The Nuclear Magnetic Resonance (NMR) technique is a powerful tool used in biophysics to study the structure, dynamics, and interactions of biomolecules in solution. NMR spectroscopy is based on the principle that certain atoms’ nuclei can absorb and emit electromagnetic radiation in the radiofrequency range when placed in a strong magnetic field. This technique can…
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X-ray Diffraction Technique
The X-ray diffraction (XRD) technique is a powerful tool for studying the structure of crystalline materials. It works by shining X-rays on a crystalline material and detecting the diffracted X-rays on a detector, creating a pattern of diffraction peaks. The angle and intensity of these peaks can be used to determine the crystal structure, unit…
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Circular Dichroism (CD) Technique
Circular dichroism (CD) is a powerful spectroscopic technique used to study the structure and properties of chiral molecules, such as proteins, nucleic acids, and carbohydrates. It is based on the differential absorption of left and right circularly polarized light by chiral molecules, which can provide information on their secondary, tertiary, and quaternary structures. In this…
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SURFACE PLASMON RESONANCE (SPR)
Surface Plasmon Resonance (SPR) is a powerful label-free technique used for real-time monitoring of biomolecular interactions. This article provides a comprehensive study of the SPR technique, covering its principles, instrumentation, applications, factors affecting the SPR response, advantages and limitations, future directions, and more. With 15 headings and FAQs, this article is a valuable resource for…
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Magnetic Resonance Imaging (MRI)
Magnetic Resonance Imaging (MRI) is a medical imaging technique that creates detailed images of the internal structures of the body using magnetic fields and radio waves. MRI is a non-invasive diagnostic tool that provides high-quality images of soft tissues, organs, and bones without exposing patients to harmful radiation. The basic principle of MRI is to…
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Restriction Endonucleases
Restriction endonucleases, the DNA-cutting enzymes, are indispensable in molecular biology research. Classified into four types based on recognition sites, Type II enzymes stand out as the most widely used. They cleave DNA at specific sequences, generating fragments with blunt or sticky ends. Despite their complexity, Type I and III enzymes have limited use due to…
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Mass Spectrometry (MS) Technique
The article discusses the principles, techniques, and applications of Mass Spectrometry (MS) from a biophysics perspective. It explains how MS is used to study the structure, dynamics, and interactions of biomolecules and how it can be applied to a wide range of biomolecules, including proteins, nucleic acids, lipids, and small molecules. The article also discusses…
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Functional Magnetic Resonance Imaging
Functional Magnetic Resonance Imaging (fMRI) is a powerful medical imaging technique used to study brain function. It measures changes in blood flow in the brain using MRI technology, which can be used to infer changes in neural activity. fMRI is commonly used in neuroscience, psychology, and psychiatry to investigate a wide range of questions related…
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CT Scan Technique
CT (Computed Tomography) scan is a widely used medical imaging technique that produces detailed, cross-sectional images of the body using x-rays and computer technology. The technique uses x-ray detectors, reconstruction algorithms and dose management techniques to minimize the radiation dose to the patient while producing high-quality images. Specialized CT scans such as CT angiography, CT…
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Cryo Electron Microscopy (Cryo-EM)
Cryo-EM is a cutting-edge imaging technique used for studying the structure of biological macromolecules such as proteins and nucleic acids. By using a cryogenic electron microscope, researchers can capture high-resolution images of frozen, hydrated samples, preserving their native state and avoiding radiation damage. The sample preparation is a crucial step that involves rapid freezing of…
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Patch Clamp Technique
The patch clamp technique is a widely used electrophysiological method for studying ion channels in cell membranes. This technique involves using a micropipette to form a gigaohm seal with a cell membrane, allowing for the manipulation of the electrical potential across the membrane. There are four main types of patch clamp, each with their own…
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ECG (Electrocardiogram)
The electrocardiogram (ECG) is a widely used diagnostic tool for the evaluation of heart conditions. It is a non-invasive test that records the electrical activity of the heart and displays it as waves on a graph. The ECG is used to diagnose a variety of heart conditions such as arrhythmias, heart attacks, and other cardiac…
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PET (Positron Emission Tomography)
The article provides an in-depth study note on Positron Emission Tomography (PET), a non-invasive nuclear medicine imaging technique that uses small amounts of radioactive materials to produce images of the body’s biological processes. It explains the principles of the PET imaging technique, the use of radiotracers, its applications in detecting and diagnosing various diseases, and…
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Beer-Lambert Law and Spectrophotometry
Discover the principles of the Beer-Lambert Law and its application in spectrophotometry. Explore how this law relates the concentration of a solute to absorbance, and its significance in quantitative analysis, chemical kinetics, environmental monitoring, pharmaceutical analysis, and biochemical assays. Unlock the power of spectrophotometry in understanding chemical substances and their characteristics.
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Freeze Fracture Technique
The Freeze Fracture Technique is a powerful method utilized in the study of cell biology and other biological samples. By freezing and breaking a sample, its internal structure is revealed and can be examined under an electron microscope. This technique is commonly applied to investigate cell membranes, organelles, microorganisms, as well as in fields like…
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Northern blotting
Northern blotting is a technique used in molecular biology and medical research to analyze and detect specific RNA sequences. It involves the separation of RNA by electrophoresis and detection through hybridization. This powerful method has applications in genetics, diagnostics, and environmental monitoring, providing valuable insights into diseases and genetic disorders. Discover more about the principles,…
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