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High-performance liquid chromatography (HPLC) is a technique in analytical chemistry used to separate the components in a mixture, and to identify and quantify each component. It was initially discovered as an analytical technique in the early twentieth century and was first used to separate colored compounds. The word chromatography means color writing . It was the botanist M. S. Tswett ( [link] ) who invented this method in around 1900 to study leaf pigments (mainly chlorophyll). He separated the pigments based on their interaction with a stationary phase. In 1906 Tswett published two fundamental papers describing the various aspects of liquid-adsorption chromatography in detail. He also pointed out that in spite of its name, other substances also could be separated by chromatography. The modern high performance liquid chromatography has developed from this separation; the separation efficiency, versatility and speed have been improved significantly.

Russian born Italian botanist Mikhail Semyonovich Tswett (1872-1919).

The molecular species subjected to separation exist in a sample that is made of analytes and matrix . The analytes are the molecular species of interest, and the matrix is the rest of the components in the sample. For chromatographic separation, the sample is introduced in a flowing mobile phase that passes a stationary phase . Mobile phase is a moving liquid, and is characterized by its composition, solubility, UV transparency, viscosity, and miscibility with other solvents. Stationary phase is a stationary medium, which can be a stagnant bulk liquid, a liquid layer on the solid phase, or an interfacial layer between liquid and solid. In HPLC, the stationary phase is typically in the form of a column packed with very small porous particles and the liquid mobile phase is moved through the column by a pump. The development of HPLC is mainly the development of the new columns, which requires new particles, new stationary phases (particle coatings), and improved procedures for packing the column. A picture of modern HPLC is shown in [link] .

A picture of modern HPLC instrument.


The major components of a HPLC are shown in [link] . The role of a pump is to force a liquid (mobile phase) through at a specific flow rate (milliliters per minute). The injector serves to introduce the liquid sample into the flow stream of the mobile phase. Column is the most central and important component of HPLC, and the column’s stationary phase separates the sample components of interest using various physical and chemical parameters. The detector is to detect the individual molecules that elute from the column. The computer usually functions as the data system, and the computer not only controls all the modules of the HPLC instrument but it takes the signal from the detector and uses it to determine the retention time, the sample components, and quantitative analysis.

Schematic representation of a HPLC system: (1) solvent, (2) gradient valve, (3) high-pressure pump, (4) sample injection loop, (5) analytical column, (6) detector, and (7) computer.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
Privacy Information Security Software Version 1.1a
advantages of NAA
Sai Reply
how I can reaction of mercury?
Sham Reply

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