Heinrich Schnitger (10 May 1925 in Lemgo - 27 August 1964 in Upper Bavaria) was a German physician. He is considered the inventor of the piston stroke Micropipette, a laboratory device for dispensing small amounts of liquid.
Heinrich Schnitger (10 May 1925 in Lemgo - 27 August 1964 in Upper Bavaria) was a German physician. He is considered the inventor of the piston stroke Micropipette, a laboratory device for dispensing small amounts of liquid.
Heinrich Schnitger was born in 1925 in Lemgo, Westphalia, Germany, the son of an inventor who designed, among other things, a once widely used bicycle lock. As a young boy, Schnitger had already tinkered with and made many changes and improvements to various gadgets. After suffering from tuberculosis as a soldier in the Second World War, he decided to study medicine. He attained PhD after studying medicine in 1956 at the Philipps University of Marburg with a thesis on the development of a device for the automated determination of blood clotting times . During his subsequent work at the Institute of Physiological Chemistry University of Marburg, among other things, he worked on large amounts of chromatography samples with a volume of less than a milliliter for further analysis. At that time the usual method was to use thin glass pipettes in which the fluids were aspirated directly or via a hose to the mouth.
Heinrich Schnitger constructed in the spring of 1957 in cooperation with the mechanical workshop of the Institute for this work a novel device with which it was possible to dispense small amounts of fluid quickly and precisely by hand. In the same year he presented under the title "A rapid and precise pipetting of small liquid quantities" a patent at the German Patent Office one, issued in 1961. The company Eppendorf improved the first "Marburg pipette" sold apparatus in cooperation with Heinrich Schnitger on and took over the exclusive license of the patent for commercialization.
Heinrich Schnitger died in 1964, before the global spread of his invention, due to an accident while swimming in a mountain lake in Upper Bavaria.
The Micropipette developed by Heinrich Schnitger, which is often referred to as "Eppendorf pipette" in laboratory usage, [ citation needed ] counts today in various designs as standard almost every biomedical laboratories. For biologists, biochemists, biology laboratory technicians, medical-technical assistants and similar professions handling of these devices is an integral part of education and often a daily part of their work. For manual dosing of small volumes in the field of biomedical research, clinical chemistry, and the environmental and food analysis micropipettes have almost completely replaced other methods due to their ease of use and its precision.
The main contribution of Eppendorf, by the commercial success of the piston stroke was the development of interchangeable pipette tips made of polyethylene and polypropylene . From the American Gilson, attributed by Schnitger's invention in the early years of little importance, came in the early 1970s, the first piston pipettes with variably adjustable pipetting on the market, currently represent the most commonly used form. Further, based on the developed by Heinrich Schnitger basic principle variants are called multi-channel pipettes for simultaneous dosing over eight or twelve channels and pipettes with electronic adjustment and control of dosage.
An engine or motor is a machine designed to convert one form of energy into mechanical energy. Heat engines convert heat into work via various thermodynamic processes. The internal combustion engine is perhaps the most common example of a heat engine, in which heat from the combustion of a fuel causes rapid pressurisation of the gaseous combustion products in the combustion chamber, causing them to expand and drive a piston, which turns a crankshaft. Electric motors convert electrical energy into mechanical motion, pneumatic motors use compressed air, and clockwork motors in wind-up toys use elastic energy. In biological systems, molecular motors, like myosins in muscles, use chemical energy to create forces and ultimately motion.
A carburetor or carburettor is a device that mixes air and fuel for internal combustion engines in an appropriate air–fuel ratio for combustion. The term is sometimes colloquially shortened to carb in the UK and North America or to carby in Australia. To carburate or carburete means to mix the air and fuel or to equip with a carburetor for that purpose.
A burette is a graduated glass tube with a tap at one end, for delivering known volumes of a liquid, especially in titrations. It is a long, graduated glass tube, with a stopcock at its lower end and a tapered capillary tube at the stopcock's outlet. The flow of liquid from the tube to the burette tip is controlled by the stopcock valve. There are two main types of burette; the volumetric burette and the Piston burette or Digital burette.
A pipette is a laboratory tool commonly used in chemistry, biology and medicine to transport a measured volume of liquid, often as a media dispenser. Pipettes come in several designs for various purposes with differing levels of accuracy and precision, from single piece glass pipettes to more complex adjustable or electronic pipettes. Many pipette types work by creating a partial vacuum above the liquid-holding chamber and selectively releasing this vacuum to draw up and dispense liquid. Measurement accuracy varies greatly depending on the instrument.
A syringe is a simple reciprocating pump consisting of a plunger that fits tightly within a cylindrical tube called a barrel. The plunger can be linearly pulled and pushed along the inside of the tube, allowing the syringe to take in and expel liquid or gas through a discharge orifice at the front (open) end of the tube. The open end of the syringe may be fitted with a hypodermic needle, a nozzle or tubing to direct the flow into and out of the barrel. Syringes are frequently used in clinical medicine to administer injections, infuse intravenous therapy into the bloodstream, apply compounds such as glue or lubricant, and draw/measure liquids.
A Stirling engine is a heat engine that is operated by the cyclic compression and expansion of air or other gas at different temperatures, resulting in a net conversion of heat energy to mechanical work. More specifically, the Stirling engine is a closed-cycle regenerative heat engine with a permanent gaseous working fluid. Closed-cycle, in this context, means a thermodynamic system in which the working fluid is permanently contained within the system, and regenerative describes the use of a specific type of internal heat exchanger and thermal store, known as the regenerator. Strictly speaking, the inclusion of the regenerator is what differentiates a Stirling engine from other closed-cycle hot air engines.
The Brayton cycle is a thermodynamic cycle named after George Brayton that describes the workings of a constant-pressure heat engine. The original Brayton engines used a piston compressor and piston expander, but more modern gas turbine engines and airbreathing jet engines also follow the Brayton cycle. Although the cycle is usually run as an open system, it is conventionally assumed for the purposes of thermodynamic analysis that the exhaust gases are reused in the intake, enabling analysis as a closed system.
The patch clamp technique is a laboratory technique in electrophysiology used to study ionic currents in individual isolated living cells, tissue sections, or patches of cell membrane. The technique is especially useful in the study of excitable cells such as neurons, cardiomyocytes, muscle fibers, and pancreatic beta cells, and can also be applied to the study of bacterial ion channels in specially prepared giant spheroplasts.
A liquid handling robot is used to automate workflows in life science laboratories. It is a robot that dispenses a selected quantity of reagent, samples or other liquid to a designated container.
Microinjection is the use of a glass micropipette to inject a liquid substance at a microscopic or borderline macroscopic level. The target is often a living cell but may also include intercellular space. Microinjection is a simple mechanical process usually involving an inverted microscope with a magnification power of around 200x.
Eppendorf, a company with its registered office in Germany, develops, produces and sells products and services for laboratories around the world.
A hydraulic motor is a mechanical actuator that converts hydraulic pressure and flow into torque and angular displacement (rotation). The hydraulic motor is the rotary counterpart of the hydraulic cylinder as a linear actuator. Most broadly, the category of devices called hydraulic motors has sometimes included those that run on hydropower but in today's terminology the name usually refers more specifically to motors that use hydraulic fluid as part of closed hydraulic circuits in modern hydraulic machinery.
An eye dropper, also known as a Pasteur pipette, or dropper, is a device used to transfer small quantities of liquids. They are used in the laboratory and also to dispense small amounts of liquid medicines. A very common use was to dispense eye drops into the eye. The commonly recognized form is a glass tube tapered to a narrow point and fitted with a rubber bulb at the top, although many styles of both plastic and glass droppers exist. The combination of the pipette and rubber bulb has also been referred to as a teat pipette. The Pasteur pipette name is from the French scientist Louis Pasteur, who used a variant of them extensively during his research. In the past, there was no equipment to transfer a chemical solution without exposing it to the external environment. The hygiene and purity of chemical compounds is necessary for the expected result of each experiment. The eye dropper, both glass and plastic types, can be sterilized and plugged with a rubber bulb at the open end of the pipette preventing any contamination from the atmosphere. Generally, they are considered cheap enough to be disposable, however, so long as the glass point is not chipped, the eye dropper may be washed and reused indefinitely.
A micromanipulator is a device which is used to physically interact with a sample under a microscope, where a level of precision of movement is necessary that cannot be achieved by the unaided human hand. It may typically consist of an input joystick, a mechanism for reducing the range of movement and an output section with the means of holding a microtool to hold, inject, cut or otherwise manipulate the object as required. The mechanism for reducing the movement usually requires the movement to be free of backlash. This is achieved by the use of kinematic constraints to allow each part of the mechanism to move only in one or more chosen degrees of freedom, which achieves a high precision and repeatability of movement, usually at the expense of some absolute accuracy.
Piston-driven air displacement pipettes are a type of micropipette, which are tools to handle volumes of liquid in the microliter scale. They are more commonly used in biology and biochemistry, and less commonly in chemistry; the equipment is susceptible to damage from many organic solvents.
An automatic soap dispenser is a device that dispenses a controlled amount of soap solution. They are often used in conjunction with automatic faucets in public restrooms. They function to conserve the amount of soap used and stem infectious disease transmission.
An automated pipetting system is generally a device which performs programmed transfers of liquid between preselected groups of containers.
Reverse pipetting is a technique to dispense a measured quantity of liquid by means of air displacement pipette. The technique is mainly recommended for solutions with a high viscosity or a tendency to foam: as it reduces the risk of splashing, foam or bubble formation. Reverse pipetting is more precise in dispensing small volumes of liquids containing proteins and biological solutions compared to forward pipetting, which is mostly used for aqueous solutions, such as buffers, diluted acids or alkalis.
A media dispenser or a culture media dispenser is a device for repeatedly delivering small fixed volumes of liquid such as a laboratory growth medium like molten agar or caustic or volatile solvents like toluene into a series of receptacles. It is often important that such dispensers operate without biological or chemical contamination, and so must be internally sealed from the environment and designed for easy cleaning and sterilization before use. At a minimum, a media dispenser consists of some kind of pump connected to a length of discharge tubing or a spout. Dispensers used in laboratories are also frequently connected to microcontrollers to regulate the speed and volume of the medium as it leaves the pump.
An internal combustion engine (ICE) is a heat engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal combustion engine, the expansion of the high-temperature and high-pressure gases produced by combustion applies direct force to some component of the engine. The force is applied typically to pistons, turbine blades, a rotor, or a nozzle. This force moves the component over a distance, transforming chemical energy into useful work. This replaced the external combustion engine for applications where weight or size of the engine is important.
