Words used in the catalogue. Choose a letter, read the explanation, and open a collection. Short names such as USP sit on the abbreviations page.
Accuracy class AS is class A with a short waiting time, on volumetric pipettes and burettes. The S comes from the German schnell. On a 40 ml volumetric pipette the waiting time is 5 s. Where AS is followed by a number, it is a model name.
An acid gives up a proton. In the catalogue the grade says which impurities are limited. Mineral acids and organic acids sit on the acids shelf.
An alkali is a base that dissolves in water and raises the pH, such as sodium hydroxide or ammonia solution. The strength and the concentration are both part of the order.
An amino acid is a building block of a peptide and of a protein. The L or D form, and a free acid or a salt, are different articles.
An analytical balance reads a small mass, to 0.1 mg or finer. A precision balance reads a coarser step and lives on the next shelf. The instrument is a balance.
Analytical grade limits the impurities that would disturb a titration, a digestion or a photometric reading. A chemical marked ACS meets that reagent specification for analysis. The same name on a solvent means the solvent grade.
An antibiotic limits the growth of bacteria. In cell culture and in microbiology it is a selective agent in the medium. The organism it acts on is part of the choice.
An antibody binds one target. A primary antibody sees the sample. A secondary antibody sees the primary and usually carries the label that the reader detects.
An autoclave sterilises with steam under pressure. The cycle states a temperature and a holding time. Glassware, media and waste each need their own cycle.
An autosampler vial is the small closed bottle a chromatograph picks up by itself. The neck, the cap and the septa have to match the tray.
A base accepts a proton. A strong base and a weak base are different reagents, and a solid base and its solution are different articles.
A beaker is an open cylindrical vessel with a spout, for dissolving, heating and rough volumes. It is a working vessel. A volumetric flask is the vessel that delivers a stated volume.
A Buchner funnel is a rigid filter funnel used with vacuum. The paper or the frit sits on a perforated plate, and the filtrate is pulled through.
A buffer resists a change in pH when a little acid or base is added. The pH, the concentration and the chemical family are the specification. A biological buffer and a pH standard for a meter are different shelves.
A burette delivers a measured volume in a titration, read from the glass scale. Class AS names the tolerance and a short waiting time. A burette marked DE-M has been assessed under the German measurement act.
A calibration weight is a mass of a stated class, used to check a balance. The class after OIML, such as E1 or E2, is that accuracy class.
A carbohydrate is a sugar or a chain of sugars. A hydrate and an anhydrous grade are different masses for the same named sugar. The grade says which impurities were limited.
Cell culture grows cells outside the organism, in a flask or a plate, in a medium. The medium, the serum and the vessel are separate articles. A sterile surface is part of the method.
A centrifuge spins samples so that denser material moves outward. The rotor, the speed and the tube have to match. A microcentrifuge and a floor-standing centrifuge are different instruments on this shelf.
A centrifuge tube is the vessel that goes in the rotor. The volume, the material and the maximum speed belong together. A tube rated below the run will fail in the rotor.
Chromatography separates compounds by how they move between a mobile phase and a stationary phase. HPLC is the liquid method under pressure. Gas chromatography and TLC are the other two large shelves.
Click chemistry joins two groups that react with each other and with little else, often an azide and an alkyne. It is a way to build or to label a molecule. The reagents sit with the organic synthesis reagents.
Conductivity is how well a solution carries an electric current. Ions raise it. A meter reads it through a cell, and a standard solution checks that cell.
A crucible is a small cup for strong heat: an ashing, a fusion or a ignition. Porcelain, platinum and other materials survive different temperatures.
A cryogenic vial stores a sample in a freezer or in liquid nitrogen. The cap, the seal and the temperature rating are the specification. A ordinary reaction tube is a different vessel.
A culture medium feeds microorganisms, as a powder to dissolve or as a ready plate. A medium marked Ph. Eur. meets that pharmacopoeia. The organism the formula selects is written on the article.
A cuvette is the small transparent cell a photometer looks through. The path length, often 10 mm, and the material, glass or plastic, decide which wavelengths pass.
A desiccator is a closed vessel that keeps a sample dry, over a desiccant or under vacuum. It cools a dried crucible without letting moisture back in.
A deuterated solvent has hydrogen replaced by deuterium, so the solvent peak stays small in an NMR spectrum. The degree of deuteration is the grade. The sample sits in an NMR tube.
A disinfectant reduces microbes on a surface or in a liquid. The contact time and the spectrum are the instruction. A cleaner that only removes dirt is on the cleaning shelf beside it.
Distillation separates liquids by their boiling point. The vapour rises, a condenser turns it back into liquid, and the receiver collects it. A rotary evaporator does this under vacuum, on its own shelf.
A dry solvent has had most of its water removed. Water would stop some reactions, so the residual water is the specification. It is a different article from the ordinary solvent of the same name.
A drying oven holds glassware or a sample at a set temperature in air, to drive off moisture. A climate chamber also holds a set humidity. The two sit on one shelf.
A dye is a coloured compound used to stain a tissue, a cell or a fibre, or as a pigment. The colour index and the grade say which article it is. A stain for the microscope has its own shelf.
Electrophoresis moves charged molecules through a gel in an electric field. Smaller molecules travel farther in a given time. The gel, the comb and the power supply are the parts of the run.
ELISA reads how much of a target is in a sample, with an antibody on a plate and an enzyme that makes a colour. A kit holds the plate, the standards and the reagents for that one assay.
An enzyme is a protein that speeds one reaction. The substrate is the molecule it acts on. Activity is stated in units, and those units belong to that method.
An Erlenmeyer flask has a flat base and a cone that rises to a narrow neck. The shape lets a liquid be swirled with less spill. It is a working flask, with a volume mark that is approximate.
An essential oil is the volatile fraction distilled or pressed from a plant. The plant, the part used and the country are the identity. It sits with the natural products.
An excipient is a substance in a preparation besides the active ingredient: a filler, a solvent or a carrier. On this shelf it meets a pharmacopoeia monograph, such as USP, BP or Ph. Eur..
Filter paper is a cellulose sheet that holds solids and lets liquid through. The speed, the retention and the ash content after burning are the grades. A membrane filter is a different sheet, with a stated pore size.
Filtration separates a solid from a liquid, or a particle from a solution, by a sheet with openings. Paper, a membrane and a syringe filter are three forms. The pore size, when stated, is the cut.
A fume cupboard pulls air away from the bench so that vapour from a reaction leaves the room. The sash and the airflow are part of the cabinet. It is a fixed safety installation.
A funnel guides a liquid into a narrow neck. A separating funnel also lets two liquid layers be split. A Buchner funnel is the filter form, used with vacuum.
Gas chromatography carries a vaporised sample through a column in a stream of gas. Compounds leave the column at different times. A capillary column is the usual column on this shelf.
A laboratory glove is a barrier for the hand. Nitrile, latex and vinyl are disposable grades. A chemical-resistant glove is a thicker article, for a named chemical and a named contact time.
A graduated pipette has a scale along the tube, so several volumes can be delivered from one pipette. Class AS names the tolerance and a short waiting time. A volumetric pipette has one mark and one volume.
A green solvent is chosen because its source or its hazard profile differs from a classical solvent of the same job. It still has a boiling point, a purity and a water content. Those three decide whether it can replace the other solvent.
A ground joint is a tapered glass cone and socket that seal without a rubber stopper. NS followed by a size, such as NS 14.5, names that joint. Two pieces join only when the numbers match.
High-density polyethylene, HDPE, is the rigid grade of polyethylene, used for bottles and caps. It holds its shape. The flexible grade is LDPE.
HPLC pushes a liquid sample through a packed column under pressure. Compounds leave at different times. The column, the particle size and a solvent of HPLC grade decide the separation.
Histology prepares a tissue so it can be cut and stained, then read under a microscope. Cassettes, moulds, stains and slides are the articles around that work.
A hydrometer is a floating glass scale that reads the density of a liquid from how deep it sinks. The liquid has to match the range printed on the stem.
An incubator holds culture vessels at a set temperature for hours or days. Some also hold a set carbon dioxide level for cells. It is a heated cabinet.
An indicator changes colour at a point in a titration or at a pH. The transition interval is the specification. A ready solution and the solid dye are different articles.
An inorganic chemical is a salt, a metal, an oxide or an element. In the ordinary sense it is a compound whose skeleton is not built on carbon. The water of hydration is part of the formula: a hydrate and the anhydrous salt are different masses for the same ion.
An inorganic salt is an ionic solid, such as a chloride, a sulfate, a nitrate or a phosphate. The degree of hydration changes the mass that contains one mole of the ion. Analytical grade limits the foreign ions.
An ion standard is a solution of a known concentration of one element or of several. Standards marked ICP are made for inductively coupled plasma measurement. The concentration and the matrix are the specification.
A lab coat is the cloth layer over clothing. Cotton, a blend or a disposable coat protect against splashes in different ways. The size and how the front closes are part of the article.
A laboratory bottle stores a liquid under a screw cap. GL followed by a number, such as GL 45, names the thread. ISO 4796 names a glass bottle of that standard. A thread described as DIN follows a DIN designation.
A lipid is a fat, an oil, a fatty acid or a steroid, poorly soluble in water. The chain length and a salt or a free acid are different articles of the same family.
A magnetic stirrer spins a bar inside the vessel from a magnet under the plate. The bar has to fit the flask. Many plates also heat.
A measuring cylinder reads an approximate volume from a scale on a tall glass or plastic tube. It is for preparing, and a volumetric flask is for a stated volume. Class A and class B name the tolerance.
A membrane filter is a thin sheet with a stated pore size, such as 0.2 µm or 0.45 µm. PES, PTFE and PVDF are membrane materials. A syringe filter is that sheet in a small housing.
A metal on this shelf is the element or a simple form of it, as powder, shot or sheet. An oxide of the same element is a different article. The purity and the particle size are the specification.
Microbiology works with bacteria, yeasts and other microorganisms. Media, Petri dishes and loops are the articles around a culture. A medium marked for a pharmacopoeia follows that monograph.
A microscope makes a small object large enough to see. A light microscope uses lamps and lenses. Slides and cover glasses hold the specimen. Fluorescence needs a filter set matched to the dye.
A moisture analyser is a balance with a heater over the pan. It follows the mass while the sample dries, and reports the loss as moisture. The drying program and the readability are the specification.
Molecular biology works with DNA, RNA and the enzymes that copy or cut them. Extraction kits, nucleotides and a polymerase are typical articles. PCR is the copying method.
A mortar is a bowl, and the pestle is the club that grinds a solid in it. Porcelain, glass and agate shed different amounts into the sample. The material is part of the choice.
A nanomaterial has particles so small that the size itself is a property, often below 100 nm. The particle size joins the chemical identity in the specification. An ordinary powder of the same formula is a different article.
A natural product is a compound obtained from a plant, an animal or a microorganism, rather than built only from small synthetic blocks. The source and the purity define the article. Essential oils are the volatile part of that shelf.
A nitrile glove is a disposable glove of synthetic rubber, worn where latex is avoided. Thickness and length change the barrier. A powder-free glove and a powdered glove are different articles.
NMR reads how certain nuclei sit in a molecule, from a sample in a thin glass tube. A deuterated solvent keeps the solvent signal small. The tube diameter has to match the probe.
A nucleotide is a building block of DNA or RNA. In a PCR the polymerase adds nucleotides to the growing strand. A master mix that already contains them does not need a second addition.
An organic chemical is built on carbon. In this catalogue it is a building block or a reagent for making another molecule: a starting material, a coupling agent, a polymer or a PEG. The structure and the grade decide whether two bottles are the same substance. Purity is a statement of which impurities remain.
An overhead stirrer drives a shaft that enters the vessel from above. It stirs volumes and viscosities that a magnetic bar cannot move. The shaft and the blade are chosen for the vessel.
An oxide is a compound of an element with oxygen, such as a metal oxide. It is a different article from the metal itself. The purity and, for a powder, the particle size are the specification.
A PCR plate holds many small wells for a PCR, so an instrument can read a whole plate. The skirt, the colour and the well volume have to match the block. Tubes and strips are the smaller forms.
Perfluoroalkoxy, PFA, is a fluoropolymer that can be moulded into tubing and vessels. It resists strong chemicals and stays clear enough to see the liquid. It is a different plastic from PTFE.
A Petri dish is a flat lidded dish for a gel of culture medium. Colonies grow on the surface. The diameter and a sterile or non-sterile pack are the choice.
pH is a number for how acidic or alkaline a solution is. A pH meter reads it with an electrode, checked against buffer standards. A buffer resists a drift of that number.
A pharmacopoeia is a published book of monographs for reagents and excipients. The monograph, not the common name, fixes the identity tests and the impurity limits. USP is the United States Pharmacopeia. BP is the British Pharmacopoeia. Ph. Eur. is the European Pharmacopoeia. DAB is the German pharmacopoeia. Meeting one monograph does not by itself mean the article meets another.
A pipette delivers a volume of liquid. A volumetric pipette has one mark. A graduated pipette has a scale. A piston pipette is the handheld instrument with a tip. Class AS applies to the glass volumetric and graduated forms.
Polyethersulfone, PES, is a membrane plastic used in syringe filters and membrane discs. It wets with water and has a low binding of protein. The pore size is still the cut that the filter makes.
Polyethylene is the polymer of ethylene. The rigid grade, HDPE, is used for bottles and caps. The flexible grade, LDPE, is used for bags and soft tubing. A plastic bottle on the bottle shelf is often the rigid grade.
Polyethylene glycol, often called PEG, is a water-soluble polymer of ethylene oxide. The average chain length, written as a number after PEG, changes the melting point and the use. It sits with the polymers.
A polymer is a long molecule built by repeating a smaller unit. A PEG, a silicone and a plastic resin are polymers. The average size of the chain is part of the name, because a short chain and a long chain behave differently.
A polymerase is the enzyme that copies a nucleic acid, adding nucleotides to a growing strand. In a PCR the tube also holds nucleotides and a buffer, often already combined as a master mix. A hot-start enzyme and a proofreading enzyme do different jobs. Adding nucleotides again to a master mix that already contains them spoils the reaction.
Polypropylene, PP, is a rigid plastic used for bottles, tubes and small vials. It keeps its shape when warm and can be autoclaved in many grades. A plastic bottle on the bottle shelf may be this plastic or polyethylene.
Polytetrafluoroethylene, PTFE, is a smooth fluoropolymer used for seals, stopcocks, tubing and filter membranes. Very little sticks to it. It is the membrane in many solvent-resistant syringe filters.
Polyvinylidene fluoride, PVDF, is a fluoropolymer membrane in syringe filters. It binds protein less than some other membranes and stands up to many solvents. The pore size is chosen for the sample.
A precision balance reads a mass to a step coarser than an analytical balance, often 1 mg or 0.01 g, and it takes a heavier load. The readability and the capacity are the two numbers that choose it.
A protein is a chain of amino acids folded into a working shape. Extraction, a marker and a purification resin are the articles around it. An antibody is a protein with a chosen target.
A reference material is the article against which another result is compared. Its value is stated, and the uncertainty of that value is part of the product. A standard solution and a neat reference substance are two forms.
Reversed phase, RP, is a chromatography mode in which the column is less polar than the liquid running through it. Many HPLC columns work in this mode. The carbon chain on the silica, such as C18, is the phase.
A rotary evaporator removes a solvent under vacuum while the flask turns in a warm bath. Turning spreads the liquid as a film, so it evaporates faster. The vacuum pump is a separate instrument.
A round-bottom flask is the spherical flask used for heating and for distillation. The neck is often a ground joint. The volume is the working size, and the joint size has to match the rest of the rig.
A safety cabinet stores flammable liquids or aggressive chemicals so that a fire or a leak stays inside the cabinet. The rating says which liquids it is built for. It is storage, and a fume cupboard is the place where a bottle is opened for work.
Safety glasses shield the eyes from a splash or a flying chip. Side shields are part of that. Goggles seal to the face and are a different article, for more splash.
Solid-phase extraction, SPE, pulls a sample through a small cartridge so that the compound of interest sticks and the rest washes away. The sorbent in the cartridge is the choice. A manifold holds several cartridges under vacuum.
A solvent dissolves another substance. Analytical grade, HPLC grade, a dry grade and a technical grade limit different impurities. The same chemical name in two grades can be two articles.
A Soxhlet extractor washes a solid many times with the same solvent. The solvent boils, condenses, fills the chamber and siphons back. It extracts a fat or another soluble fraction from a sample.
Spectroscopy reads how a sample takes up or gives off light at given wavelengths. A photometer or a spectrophotometer is the instrument. The cuvette holds the liquid in the beam.
A stain is a dye solution that colours a cell or a tissue so that structures become visible under the microscope. The ready solution and the powder are different articles. Histology uses a set of stains in a fixed order.
A syringe filter is a small membrane in a housing, pushed by a syringe, to clear a sample before an instrument. PES, PTFE and PVDF are common membranes. The pore size and the solvent decide which one.
A test sieve sorts particles by whether they pass an opening of a stated size. The mesh and the frame diameter are the specification. A sieve shaker repeats the motion so the result can be compared.
A test tube is a slim glass or plastic tube for a small reaction or a sample. A rim and a cap are options. It is not a volumetric vessel: the volume mark, when there is one, is approximate.
A laboratory thermometer reads temperature, as a glass capillary or as a digital probe. An ASTM thermometer follows a named ASTM method and has a stated range and immersion. The immersion depth is part of a correct reading.
Thin-layer chromatography, TLC, separates a sample on a thin layer coated on a plate. The solvent climbs the plate and carries the spots at different speeds. The plate, the layer and the chamber are the articles.
A titration adds a solution of known concentration until the reaction with the sample reaches an end point. A burette delivers the volume by hand. A titrator does the same addition and the same end point with a motor and a sensor. The volumetric standard is the solution of known strength.
Tubing carries a liquid or a gas between two parts of a rig. The inner diameter and the material have to match the chemical and the pressure. PTFE is the smooth fluoropolymer grade. DN followed by a number names a nominal diameter.
Ultrapure water has had ions, organics and particles taken out to a stated resistivity, often 18.2 MΩ·cm at the dispenser. A cartridge set produces it from a purer feed. It is the water for sensitive analysis and for many buffers.
An ultrasonic bath cleans a piece, or disperses a solid, with high-frequency sound in a liquid. The tank volume and the frequency are the specification. The piece sits in a basket, in the liquid.
A vacuum pump lowers the pressure in a flask, a filter or a rotary evaporator. A lower pressure lets a solvent boil at a lower temperature. The ultimate vacuum and the resistance to solvent vapour choose the pump.
A viscometer measures how much a liquid resists flow. Capillary, rotational and falling-ball forms read it in different ways. The temperature of the measurement belongs with the result.
A volumetric flask holds one stated volume when it is filled to the mark, at a stated temperature. It is the flask for preparing a solution of known concentration. Class A and class B name the tolerance.
A volumetric pipette delivers one stated volume, from one mark. Class AS is class A with a short waiting time. A pipette marked USP meets that pharmacopeia. It is a different glass from a graduated pipette, which has a scale.
A volumetric standard is a solution whose concentration is known closely enough for a titration. The factor, or the exact molarity, is part of the label. It is the solution the burette delivers.
A wash bottle is a squeeze bottle that sends a fine stream of water or solvent, to rinse a precipitate or a electrode. The cap and the stem aim the stream. The plastic has to stand the liquid inside.
Water purification takes tap water toward a stated purity: ions out, organics out, particles out. A system produces pure or ultrapure water, and the cartridges are the parts that get replaced. The resistivity at the dispenser is the check.
A western blot moves proteins from a gel onto a membrane, then shows one protein with an antibody. The membrane, the paper stack and the antibody are separate articles. The transfer is the step between the gel and the detection.
