Results for "mass spectrometry"
Analytical Chemistry
Analytical chemistry is the scientific discipline focused on identifying and quantifying the composition of substances, employing both classical and advanced instrumental techniques to analyze materials across diverse fields.
ScienceProteomics
** Proteomics is the large‑scale, systematic study of the entire complement of proteins—known as the **proteome**—produced or modified by a cell, tissue, or organism, integrating composition, structure, interactions, and function. **CONTENT:** ## Overview Proteomics emerged as the logical next step after the completion of the **Human Genome Project** (2003), translating the static list of genes into dynamic, functional molecules. While a genome provides the blueprint, the proteome reflects the real‑time state of a biological system, capturing post‑translational modifications, isoforms, and protein‑protein interactions that dictate phenotype. Modern proteomics combines high‑throughput **mass spectrometry (MS)**, advanced separation techniques (e.g., two‑dimensional gel electrophoresis, liquid chromatography), and powerful bioinformatics pipelines to identify and quantify thousands of proteins in a single experiment. A typical proteomic workflow begins with sample preparation—cell lysis, protein extraction, and enzymatic digestion (commonly with trypsin). The resulting peptide mixture is separated by **nano‑LC** (liquid chromatography) and introduced into a mass spectrometer, where ions are measured with accuracies often better than **5 ppm**. Tandem MS (MS/MS) fragments selected ions, generating spectra that are matched against databases derived from genome sequences. Quantitative strategies such as **label‑free intensity**, **SILAC** (stable isotope labeling by amino acids in cell culture), or **TMT** (tandem mass tags) enable comparative studies across conditions, disease states, or developmental stages. Beyond cataloguing proteins, proteomics interrogates **protein structure** (via cross‑linking MS, hydrogen‑deuterium exchange) and **interactome networks** (through affinity purification MS). These layers provide insight into signaling pathways, metabolic fluxes, and cellular responses to external stimuli, positioning proteomics as a cornerstone of **functional genomics** and systems biology. ## History/Background The term “proteome” was coined in 1995 by Marc Wilkins, envisioning a comprehensive protein inventory analogous to the genome. Early proteomic efforts relied on **2‑D gel electrophoresis**, which could resolve ~1,000 protein spots per gel but suffered from limited dynamic range and poor reproducibility. The breakthrough came in 1999 with the introduction of **MALDI‑TOF (matrix‑assisted laser desorption/ionization time‑of‑flight)** mass spectrometry, dramatically increasing throughput and sensitivity. In 2002, the **Human Proteome Project (HPP)** was launched under the Human Proteome Organization (HUPO), aiming to map all human proteins by 2020—a goal that spurred the development of standardized protocols, reference reagents, and community databases such as **ProteomeXchange**. The advent of **Orbitrap** and **Q‑TOF** instruments in the mid‑2000s delivered sub‑ppm mass accuracy and high resolution (>100,000 FWHM), enabling routine identification of low‑abundance proteins. By 2010, label‑free quantitation and isobaric tagging had become mainstream, and the first draft of the human proteome was announced in 2014, covering ~90 % of predicted proteins. The last decade has seen **single‑cell proteomics** emerge, leveraging nanodroplet sample preparation and ultra‑sensitive MS to detect >1,000 proteins from individual cells (2022). Parallel advances in **deep learning** for peptide‑spectra matching and **ion mobility separation** have further expanded depth and speed, positioning proteomics as a mature, high‑resolution “omics” discipline. ## Key Information - **Proteome size:** An average human cell expresses ~10,000–12,000 distinct proteins, with many existing as multiple **post‑translationally modified (PTM)** forms. - **Analytical platforms:** Orbitrap Fusion Lumos (resolution 500,000 at m/z 200), timsTOF Pro (ion mobility, >1 M MS/MS per day). - **Quantitative methods:** SILAC (incorporates ^13C/^15N isotopes), TMT‑16plex (allows simultaneous analysis of 16 samples). - **Databases:** UniProtKB/Swiss‑Prot, PRIDE Archive ( >30 million spectra as of 2023), PeptideAtlas. - **Major achievements:** Identification of disease biomarkers for cancers, neurodegenerative disorders, and infectious diseases; mapping of the **human interactome** (>200,000 binary interactions); elucidation of drug‑target engagement via **thermal proteome profiling**. - **Technical metrics:** Typical peptide‑level false discovery rate (FDR) <1 %; protein‑level FDR <0.5 %; dynamic range spanning >5 orders of magnitude in modern workflows. ## Significance Proteomics bridges the gap between genotype and phenotype, providing a functional read‑out that genomics alone cannot deliver. In medicine, proteomic signatures guide **precision oncology**, informing treatment selection based on tumor‑specific protein expression and phosphorylation patterns. In biotechnology, proteomics monitors **biopharmaceutical production**, ensuring product quality by detecting host‑cell protein contaminants at parts‑per‑million levels. Environmental sciences employ proteomics to assess organismal responses to pollutants, while agriculture leverages it to improve crop resilience through stress‑responsive protein networks. The field’s interdisciplinary nature—melding chemistry, biology, engineering, and computer science—has catalyzed innovations such as **microfluidic sample preparation**, **cloud‑based data analysis**, and **AI‑driven peptide identification**. As proteomics continues to scale down to single cells and up to whole‑organism atlases, it promises to unlock deeper mechanistic insights, transform diagnostics, and accelerate drug discovery, cementing its role as an indispensable pillar of modern life sciences. **INFOBOX:** - Name: Proteomics - Type: Omics discipline (large‑scale protein science) - Date: Concept introduced 1995; major methodological milestones 1999–2022 - Location: Global research community (academic, industry, clinical labs) - Known For: Systematic identification, quantification, and functional analysis of the proteome **TAGS:** proteomics, mass spectrometry, functional genomics, protein–protein interactions, biomarker discovery, single‑cell analysis, post‑translational modifications, systems biology
ScienceMass Spectrometry
Mass spectrometry is an analytical technique that identifies and quantifies compounds by measuring the mass-to-charge ratio of ions, enabling applications from drug discovery to space exploration.
ScienceChemistry Encyclopedia Entry 1775721905
The **Chemistry Encyclopedia Entry 1775721905** is a comprehensive online resource that provides in-depth information on various aspects of chemistry, including its history, key concepts, and applications, making it an essential tool for students, researchers, and professionals in the field.
ScienceChemistry Encyclopedia Entry 1776331513
** Chemistry is the scientific study of the composition, properties, and reactions of matter, encompassing a wide range of disciplines from inorganic and organic chemistry to physical and analytical chemistry. **CONTENT** ### Overview Chemistry is a fundamental branch of science that seeks to understand the intricate world of matter and its transformations. It is a vast and complex field that has been shaped by centuries of human curiosity and ingenuity. From the earliest alchemists to modern-day researchers, chemists have been driven by a desire to understand the underlying principles of matter and to harness its potential for the betterment of society. At its core, chemistry is concerned with the study of the composition, properties, and reactions of matter. This encompasses a broad range of disciplines, including inorganic and organic chemistry, physical and analytical chemistry, biochemistry, and more. Chemists use a variety of techniques, including experimentation, observation, and theoretical modeling, to gain insights into the behavior of matter and to develop new materials, technologies, and processes. ### History/Background The history of chemistry dates back to ancient civilizations, where early alchemists sought to transform base metals into gold and to discover the Philosopher's Stone. However, it wasn't until the 17th century that chemistry began to take shape as a distinct scientific discipline. In 1661, Robert Boyle published his groundbreaking work, "The Sceptical Chymist," which laid the foundations for modern chemistry by introducing the concept of the element and the law of conservation of mass. Over the centuries, chemistry continued to evolve and expand, with major breakthroughs in the 18th and 19th centuries. In 1789, Antoine Lavoisier discovered oxygen, and in 1811, Humphry Davy isolated several elements, including potassium and sodium. The 20th century saw the rise of quantum mechanics and the development of modern theoretical chemistry, which has enabled chemists to predict and design new materials and reactions with unprecedented accuracy. ### Key Information Some of the most significant facts and achievements in chemistry include: * **The Periodic Table**: Developed by Dmitri Mendeleev in 1869, the periodic table is a tabular arrangement of elements that displays their properties and relationships in a systematic and organized manner. * **Atomic Theory**: In 1911, Ernest Rutherford proposed the nuclear model of the atom, which posits that atoms consist of a small, dense nucleus surrounded by electrons. * **Chemical Bonding**: In 1927, Linus Pauling developed the theory of chemical bonding, which explains how atoms share or exchange electrons to form stable molecules. * **Molecular Structure**: In 1953, James Watson and Francis Crick discovered the double helix structure of DNA, which revolutionized our understanding of genetics and molecular biology. ### Significance Chemistry has a profound impact on our daily lives, from the food we eat and the air we breathe to the technologies that power our modern world. Chemists have developed countless materials and processes that have transformed industries and improved human health, including: * **Medicines**: Chemists have developed a wide range of medicines that have saved countless lives and improved the quality of life for millions of people. * **Materials Science**: Chemists have developed new materials with unique properties, such as plastics, ceramics, and composites, which have enabled the creation of modern technologies. * **Energy**: Chemists have developed new energy sources, such as fuels and batteries, which have transformed the way we power our homes and industries. **INFOBOX** - **Name:** Chemistry - **Type:** Branch of science - **Date:** Ancient civilizations to present day - **Location:** Global - **Known For:** Understanding the composition, properties, and reactions of matter **TAGS:** chemistry, matter, elements, compounds, reactions, acids, bases, pH, stoichiometry, thermodynamics, kinetics, spectroscopy, chromatography, mass spectrometry, nuclear chemistry, organic chemistry, inorganic chemistry, physical chemistry, analytical chemistry, biochemistry, materials science, energy, medicines, materials, technologies.
ScienceChemistry Encyclopedia Entry 1778941864
** Chemistry is the scientific study of the composition, properties, and reactions of matter, encompassing the analysis of substances, their interactions, and the transformation of one substance into another. **CONTENT:** ### Overview Chemistry is a fundamental branch of science that deals with the study of the composition, properties, and reactions of matter. It is a vast and diverse field that encompasses the analysis of substances, their interactions, and the transformation of one substance into another. Chemistry is a crucial discipline that underlies many aspects of our daily lives, from the food we eat to the medicines we take, and from the materials we use to the technologies we employ. The study of chemistry involves the examination of the atomic and molecular structure of substances, their chemical reactions, and the physical properties that govern their behavior. Chemistry is an interdisciplinary field that draws upon concepts and techniques from physics, biology, mathematics, and other sciences. It involves the use of various analytical techniques, such as spectroscopy, chromatography, and mass spectrometry, to identify and quantify the components of a substance. Chemistry also involves the synthesis of new compounds and materials, which has led to numerous breakthroughs in fields such as medicine, energy, and materials science. The study of chemistry has a rich history that spans thousands of years, with ancient civilizations such as the Egyptians, Greeks, and Romans making significant contributions to the field. However, it was not until the 18th century that chemistry began to take shape as a distinct scientific discipline, with the work of scientists such as Antoine Lavoisier and Joseph Priestley laying the foundations for modern chemistry. ### History/Background The study of chemistry dates back to ancient times, with evidence of chemical practices and knowledge found in the writings of ancient civilizations such as the Egyptians, Greeks, and Romans. The earliest recorded chemical discovery is attributed to the Egyptian alchemist, Basil Valentine, who isolated the metal mercury in the 14th century. However, it was not until the 17th and 18th centuries that chemistry began to take shape as a distinct scientific discipline. One of the key milestones in the development of modern chemistry was the discovery of the elements oxygen (O) and nitrogen (N) by Joseph Priestley in 1774 and 1772, respectively. Priestley's discovery of oxygen led to a greater understanding of combustion and respiration, while his discovery of nitrogen laid the foundation for the study of gases. Antoine Lavoisier, a French chemist, is often credited with laying the foundations for modern chemistry. In 1789, Lavoisier discovered the element oxygen and developed a systematic method of chemical nomenclature, which is still used today. He also developed the concept of chemical elements and compounds, and his work on the composition of water and the properties of acids and bases laid the foundation for modern chemistry. ### Key Information Chemistry is a vast and diverse field that encompasses many subfields, including: * **Organic chemistry**: the study of carbon-based compounds and their reactions * **Inorganic chemistry**: the study of inorganic compounds and their reactions * **Physical chemistry**: the study of the physical properties of substances and their interactions * **Analytical chemistry**: the study of the analysis and identification of substances * **Biochemistry**: the study of the chemical processes that occur within living organisms Some of the key concepts in chemistry include: * **Atomic structure**: the arrangement of electrons and protons within an atom * **Chemical bonding**: the forces that hold atoms together to form molecules * **Chemical reactions**: the transformation of one substance into another * **Chemical equilibrium**: the balance between the forward and reverse reactions in a chemical reaction ### Significance Chemistry is a crucial discipline that underlies many aspects of our daily lives. It has led to numerous breakthroughs in fields such as medicine, energy, and materials science, and has improved our understanding of the natural world. Chemistry has also played a significant role in the development of many technologies, including plastics, fertilizers, and pharmaceuticals. In conclusion, chemistry is a fundamental branch of science that deals with the study of the composition, properties, and reactions of matter. Its rich history, diverse subfields, and key concepts make it a fascinating and important discipline that continues to shape our understanding of the world around us. **INFOBOX:** - **Name:** Chemistry - **Type:** Branch of science - **Date:** Ancient civilizations (3000 BCE) - **Location:** Global - **Known For:** Analysis of substances, chemical reactions, and transformation of matter **TAGS:** chemistry, science, matter, elements, compounds, reactions, atomic structure, chemical bonding, analytical techniques, spectroscopy, chromatography, mass spectrometry, biochemistry, medicine, energy, materials science, technology, plastics, fertilizers, pharmaceuticals.
ScienceChemistry Encyclopedia Entry 1779263944
** Chemistry is the scientific study of the composition, properties, and reactions of matter, encompassing the analysis of the structure and behavior of atoms, molecules, and ions. ## Overview Chemistry is a fundamental branch of science that has been instrumental in shaping our understanding of the world around us. It is a vast and diverse field that encompasses the study of the composition, properties, and reactions of matter, from the simplest atoms to complex biological systems. Chemistry is a multidisciplinary field that draws on concepts from physics, biology, mathematics, and geology to understand the intricate relationships between matter and energy. The study of chemistry has led to numerous breakthroughs in fields such as medicine, materials science, and environmental science, and continues to play a vital role in addressing some of the world's most pressing challenges. At its core, chemistry is concerned with the interactions between atoms and molecules, and the ways in which they combine to form new substances. This involves the study of chemical reactions, which are the processes by which atoms and molecules are transformed into new substances with different properties. Chemical reactions are the foundation of many natural processes, including photosynthesis, respiration, and combustion, and are also the basis for many industrial processes, such as the production of fuels, fertilizers, and pharmaceuticals. Chemistry is a highly quantitative field, relying heavily on mathematical models and computational simulations to understand and predict the behavior of complex systems. This has led to the development of numerous tools and techniques, including spectroscopy, chromatography, and mass spectrometry, which are used to analyze and characterize the properties of matter. ## History/Background The study of chemistry dates back to ancient civilizations, with evidence of chemical practices and discoveries found in the works of ancient Greeks, Romans, and Egyptians. However, it wasn't until the 17th and 18th centuries that chemistry began to emerge as a distinct scientific discipline. This was largely due to the work of scientists such as Antoine Lavoisier, who is often credited with being the "Father of Modern Chemistry." Lavoisier's discovery of oxygen in 1778 marked a major turning point in the development of chemistry, as it led to a greater understanding of the composition of air and the role of oxygen in combustion. The 19th century saw the rise of organic chemistry, with the discovery of the structure of benzene by Friedrich August Kekulé in 1865. This led to a greater understanding of the properties and behavior of organic compounds, and paved the way for the development of modern pharmaceuticals and synthetic materials. ## Key Information Some of the key concepts and principles in chemistry include: * **Atomic structure**: The study of the arrangement of electrons and protons within atoms, and the ways in which they interact with each other. * **Chemical bonding**: The study of the forces that hold atoms and molecules together, including covalent, ionic, and metallic bonds. * **Chemical reactions**: The study of the processes by which atoms and molecules are transformed into new substances with different properties. * **Thermodynamics**: The study of the relationships between heat, work, and energy, and the ways in which they are transferred and transformed. * **Kinetics**: The study of the rates and mechanisms of chemical reactions, and the factors that influence them. Some of the key tools and techniques used in chemistry include: * **Spectroscopy**: The study of the interaction between matter and electromagnetic radiation, and the use of spectroscopic techniques to analyze and characterize the properties of matter. * **Chromatography**: The study of the separation and analysis of mixtures, and the use of chromatographic techniques to identify and quantify the components of a mixture. * **Mass spectrometry**: The study of the interaction between matter and ionizing radiation, and the use of mass spectrometric techniques to analyze and characterize the properties of matter. ## Significance Chemistry is a vital field that has a profound impact on many aspects of our lives. It has led to numerous breakthroughs in fields such as medicine, materials science, and environmental science, and continues to play a vital role in addressing some of the world's most pressing challenges. Some of the key areas where chemistry has a significant impact include: * **Medicine**: Chemistry has led to the development of numerous life-saving medications, including antibiotics, vaccines, and cancer treatments. * **Materials science**: Chemistry has led to the development of numerous advanced materials, including plastics, ceramics, and composites. * **Environmental science**: Chemistry has led to a greater understanding of the impact of human activities on the environment, and the development of strategies for mitigating and reversing environmental damage. INFOBOX: - **Name:** Chemistry - **Type:** Branch of science - **Date:** Ancient civilizations (circa 3000 BCE) - **Location:** Global - **Known For:** Development of modern pharmaceuticals, synthetic materials, and environmental science. TAGS: chemistry, atomic structure, chemical bonding, chemical reactions, thermodynamics, kinetics, spectroscopy, chromatography, mass spectrometry, materials science, environmental science, medicine, pharmaceuticals, synthetic materials.
ScienceChemistry Encyclopedia Entry 1780659905
Chemistry is the scientific study of the composition, properties, and reactions of matter, encompassing the analysis of the building blocks of the universe and the interactions between them.