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Protein electrophoresis is a method for analysing the proteins in a fluid or an extract. The electrophoresis may be performed with a small volume of sample in a number of alternative ways with or without a supporting medium:
SDS polyacrylamide gel electrophoresis (in short: gel electrophoresis, PAGE, or SDS-electrophoresis),
free-flow electrophoresis,
electrofocusing
Isoelectric focusing (IEF), also known as electrofocusing, is a technique for separating different molecules by differences in their isoelectric point (pI). It is a type of zone electrophoresis usually performed on proteins in a gel that takes ad ...
,
isotachophoresis
Isotachophoresis (ITP) is a technique in analytical chemistry used for selective separation and concentration of ionic analytes. It is a form of electrophoresis; charged analytes are separated based on ionic mobility, a quantity which tells ...
,
affinity electrophoresis
Affinity electrophoresis is a general name for many analytical methods used in biochemistry and biotechnology. Both qualitative and quantitative information may be obtained through affinity electrophoresis. The methods include the so-called elect ...
,
immunoelectrophoresis
Immunoelectrophoresis is a general name for a number of biochemical methods for separation and characterization of proteins based on electrophoresis and reaction with antibodies. All variants of immunoelectrophoresis require immunoglobulins, a ...
,
counterelectrophoresis, and
capillary electrophoresis
Capillary electrophoresis (CE) is a family of electrokinetic separation methods performed in submillimeter diameter capillaries and in micro- and nanofluidic channels. Very often, CE refers to capillary zone electrophoresis (CZE), but other electr ...
. Each method has many variations with individual advantages and limitations.
Gel electrophoresis
Gel electrophoresis is a method for separation and analysis of biomacromolecules ( DNA, RNA, proteins, etc.) and their fragments, based on their size and charge. It is used in clinical chemistry to separate proteins by charge or size (IEF ...
is often performed in combination with
electroblotting
Electroblotting is a method in molecular biology/biochemistry/ immunogenetics to transfer proteins or nucleic acids onto a membrane by using PVDF or nitrocellulose, after gel electrophoresis. The protein or nucleic acid can then be further anal ...
immunoblotting
The western blot (sometimes called the protein immunoblot), or western blotting, is a widely used analytical technique in molecular biology and immunogenetics to detect specific proteins in a sample of tissue homogenate or extract. Besides detect ...
to give additional information about a specific protein. Because of practical limitations, protein electrophoresis is generally not suited as a preparative method.
Denaturing gel methods
SDS-PAGE
SDS-PAGE,
sodium dodecyl sulfate
Sodium dodecyl sulfate (SDS) or sodium lauryl sulfate (SLS), sometimes written sodium laurilsulfate, is an organic compound with the formula . It is an anionic surfactant used in many cleaning and hygiene products. This compound is the sodium sal ...
polyacrylamide gel electrophoresis, describes a collection of related techniques to separate
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...
s according to their
electrophoretic mobility
Electrophoresis, from Ancient Greek ἤλεκτρον (ḗlektron, "amber") and φόρησις (phórēsis, "the act of bearing"), is the motion of dispersed particles relative to a fluid under the influence of a spatially uniform electric fi ...
(a function of the molecular weight of a polypeptide chain) while in the
denatured (unfolded) state. In most proteins, the binding of SDS to the polypeptide chain imparts an even distribution of charge per unit mass, thereby resulting in a fractionation by approximate size during electrophoresis.
SDS is a strong detergent agent used to denature native proteins to unfolded, individual
polypeptide
Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides.
A p ...
s. When a protein mixture is heated to 100 °C in presence of SDS, the
detergent
A detergent is a surfactant or a mixture of surfactants with cleansing properties when in dilute solutions. There are a large variety of detergents, a common family being the alkylbenzene sulfonates, which are soap-like compounds that are more ...
wraps around the polypeptide backbone. In this process, the intrinsic charges of polypeptides becomes negligible when compared to the negative charges contributed by SDS. Thus polypeptides after treatment become rod-like structures possessing a uniform charge density, that is same net negative charge per unit length. The electrophoretic mobilities of these proteins will be a linear function of the
logarithm
In mathematics, the logarithm is the inverse function to exponentiation. That means the logarithm of a number to the base is the exponent to which must be raised, to produce . For example, since , the ''logarithm base'' 10 o ...
s of their molecular weights.
Native gel methods
Native gels, also known as non-denaturing gels, analyze proteins that are still in their folded state. Thus, the electrophoretic mobility depends not only on the charge-to-mass ratio, but also on the physical shape and size of the protein.
Blue native PAGE
BN-PAGE is a native
PAGE
Page most commonly refers to:
* Page (paper), one side of a leaf of paper, as in a book
Page, PAGE, pages, or paging may also refer to:
Roles
* Page (assistance occupation), a professional occupation
* Page (servant), traditionally a young m ...
technique, where the
Coomassie brilliant blue
Coomassie brilliant blue is the name of two similar triphenylmethane dyes that were developed for use in the textile industry but are now commonly used for staining proteins in analytical biochemistry. Coomassie brilliant blue G-250 differs from ...
dye provides the necessary
charge
Charge or charged may refer to:
Arts, entertainment, and media Films
* '' Charge, Zero Emissions/Maximum Speed'', a 2011 documentary
Music
* ''Charge'' (David Ford album)
* ''Charge'' (Machel Montano album)
* ''Charge!!'', an album by The Aqu ...
s to the protein complexes for the electrophoretic separation. The disadvantage of Coomassie is that in binding to proteins it can act like a
detergent
A detergent is a surfactant or a mixture of surfactants with cleansing properties when in dilute solutions. There are a large variety of detergents, a common family being the alkylbenzene sulfonates, which are soap-like compounds that are more ...
causing complexes to
dissociate
Dissociation in chemistry is a general process in which molecules (or ionic compounds such as salts, or complexes) separate or split into other things such as atoms, ions, or radicals, usually in a reversible manner. For instance, when an acid ...
. Another drawback is the potential
quenching
In materials science, quenching is the rapid cooling of a workpiece in water, oil, polymer, air, or other fluids to obtain certain material properties. A type of heat treating, quenching prevents undesired low-temperature processes, such as pha ...
of
chemoluminescence
Chemiluminescence (also chemoluminescence) is the emission of light (luminescence) as the result of a chemical reaction. There may also be limited emission of heat. Given reactants A and B, with an excited intermediate ◊,
: + -> lozenge - ...
(e.g. in subsequent
western blot
The western blot (sometimes called the protein immunoblot), or western blotting, is a widely used analytical technique in molecular biology and immunogenetics to detect specific proteins in a sample of tissue homogenate or extract. Besides detect ...
detection or activity assays) or
fluorescence
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, tha ...
of proteins with
prosthetic group
A prosthetic group is the non-amino acid component that is part of the structure of the heteroproteins or conjugated proteins, being tightly linked to the apoprotein.
Not to be confused with the cofactor that binds to the enzyme apoenzyme (eith ...
s (e.g.
heme
Heme, or haem (pronounced / hi:m/ ), is a precursor to hemoglobin, which is necessary to bind oxygen in the bloodstream. Heme is biosynthesized in both the bone marrow and the liver.
In biochemical terms, heme is a coordination complex "consisti ...
or
chlorophyll
Chlorophyll (also chlorophyl) is any of several related green pigments found in cyanobacteria and in the chloroplasts of algae and plants. Its name is derived from the Greek words , ("pale green") and , ("leaf"). Chlorophyll allow plants to a ...
) or labelled with fluorescent dyes.
Clear native PAGE
CN-PAGE (commonly referred to as Native PAGE) separates acidic water-soluble and membrane
proteins
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...
in a
polyacrylamide
Polyacrylamide (abbreviated as PAM) is a polymer with the formula (-CH2CHCONH2-). It has a linear-chain structure. PAM is highly water-absorbent, forming a soft gel when hydrated. In 2008, an estimated 750,000,000 kg were produced, mainly fo ...
gradient gel. It uses no charged dye so the electrophoretic mobility of proteins in CN-PAGE (in contrast to the charge shift technique BN-PAGE) is related to the intrinsic charge of the proteins. The migration distance depends on the protein charge, its size and the pore size of the gel. In many cases this method has lower resolution than BN-PAGE, but CN-PAGE offers advantages whenever
Coomassie dye would interfere with further analytical techniques, for example it has been described as a very efficient microscale separation technique for
FRET
A fret is any of the thin strips of material, usually metal wire, inserted laterally at specific positions along the neck or fretboard of a stringed instrument. Frets usually extend across the full width of the neck. On some historical instrume ...
analyses. Also CN-PAGE is milder than BN-PAGE so it can retain labile supramolecular assemblies of
membrane protein
Membrane proteins are common proteins that are part of, or interact with, biological membranes. Membrane proteins fall into several broad categories depending on their location. Integral membrane proteins are a permanent part of a cell membrane ...
complexes that are
dissociate
Dissociation in chemistry is a general process in which molecules (or ionic compounds such as salts, or complexes) separate or split into other things such as atoms, ions, or radicals, usually in a reversible manner. For instance, when an acid ...
d under the conditions of BN-PAGE.
Quantitative native PAGE
The
folded protein complex
A protein complex or multiprotein complex is a group of two or more associated polypeptide chains. Protein complexes are distinct from multienzyme complexes, in which multiple catalytic domains are found in a single polypeptide chain.
Protein c ...
es of interest separate cleanly and predictably due to the specific properties of the polyacrylamide gel. The separated proteins are continuously eluted into a physiological eluent and transported to a fraction collector. In four to five PAGE fractions each the metal cofactors can be identified and absolutely quantified by high-resolution
ICP-MS
Inductively coupled plasma mass spectrometry (ICP-MS) is a type of mass spectrometry that uses an inductively coupled plasma to Ionization, ionize the sample. It atomizes the sample and creates atomic and small polyatomic ions, which are then dete ...
. The respective structures of the isolated
metalloproteins
Metalloprotein is a generic term for a protein that contains a metal ion cofactor. A large proportion of all proteins are part of this category. For instance, at least 1000 human proteins (out of ~20,000) contain zinc-binding protein domains al ...
can be determined by solution
NMR
Nuclear magnetic resonance (NMR) is a physical phenomenon in which nuclei in a strong constant magnetic field are perturbed by a weak oscillating magnetic field (in the near field) and respond by producing an electromagnetic signal with ...
spectroscopy.
Buffer systems
Most protein separations are performed using a "discontinuous" (or DISC)
buffer
Buffer may refer to:
Science
* Buffer gas, an inert or nonflammable gas
* Buffer solution, a solution used to prevent changes in pH
* Buffering agent, the weak acid or base in a buffer solution
* Lysis buffer, in cell biology
* Metal ion buffer
* ...
system that significantly enhances the sharpness of the bands within the gel. During electrophoresis in a discontinuous gel system, an ion gradient is formed in the early stage of electrophoresis that causes all of the proteins to focus into a single sharp band. The formation of the ion gradient is achieved by choosing a pH value at which the ions of the buffer are only moderately charged compared to the SDS-coated proteins. These conditions provide an environment in which
Kohlrausch's reactions determine the
molar conductivity
The molar conductivity of an electrolyte solution is defined as its conductivity divided by its molar concentration.
: \Lambda_\text = \frac,
where:
: ''κ'' is the measured conductivity (formerly known as specific conductance),
: ''c'' is the mol ...
. As a result, SDS-coated proteins are concentrated to several fold in a thin zone of the order of 19 μm within a few minutes. At this stage all proteins migrate at the same migration speed by
isotachophoresis
Isotachophoresis (ITP) is a technique in analytical chemistry used for selective separation and concentration of ionic analytes. It is a form of electrophoresis; charged analytes are separated based on ionic mobility, a quantity which tells ...
. This occurs in a region of the gel that has larger pores so that the gel matrix does not retard the migration during the focusing or "stacking" event. Separation of the proteins by size is achieved in the lower, "resolving" region of the gel. The resolving gel typically has a much smaller pore size, which leads to a sieving effect that now determines the electrophoretic mobility of the proteins. At the same time, the separating part of the gel also has a pH value in which the buffer ions on average carry a greater charge, causing them to "outrun" the SDS-covered proteins and eliminate the ion gradient and thereby the stacking effect.
A very widespread discontinuous buffer system is the tris-glycine or "
Laemmli" system that stacks at a
pH of 6.8 and resolves at a
pH of ~8.3-9.0. A drawback of this system is that these pH values may promote
disulfide
In biochemistry, a disulfide (or disulphide in British English) refers to a functional group with the structure . The linkage is also called an SS-bond or sometimes a disulfide bridge and is usually derived by the coupling of two thiol groups. In ...
bond formation between
cysteine
Cysteine (symbol Cys or C; ) is a semiessential proteinogenic amino acid with the formula . The thiol side chain in cysteine often participates in enzymatic reactions as a nucleophile.
When present as a deprotonated catalytic residue, sometime ...
residues in the proteins because the
pKa of cysteine ranges from 8-9 and because reducing agent present in the loading buffer doesn't co-migrate with the proteins. Recent advances in buffering technology alleviate this problem by resolving the proteins at a pH well below the pKa of cysteine (e.g.,
bis-tris, pH 6.5) and include reducing agents (e.g. sodium bisulfite) that move into the gel ahead of the proteins to maintain a reducing environment. An additional benefit of using buffers with lower pH values is that the acrylamide gel is more stable at lower pH values, so the gels can be stored for long periods of time before use.
SDS gradient gel electrophoresis of proteins
As voltage is applied, the anions (and negatively charged sample molecules) migrate toward the positive electrode (anode) in the lower chamber, the leading ion is
Cl− ( high mobility and high concentration); glycinate is the trailing ion (low mobility and low concentration). SDS-protein particles do not migrate freely at the border between the Cl
− of the gel buffer and the
Gly
Glycine (symbol Gly or G; ) is an amino acid that has a single hydrogen atom as its side chain. It is the simplest stable amino acid (carbamic acid is unstable), with the chemical formula NH2‐ CH2‐ COOH. Glycine is one of the proteinogeni ...
− of the cathode buffer.
Friedrich Kohlrausch found that
Ohm's law
Ohm's law states that the current through a conductor between two points is directly proportional to the voltage across the two points. Introducing the constant of proportionality, the resistance, one arrives at the usual mathematical equat ...
also applies to dissolved
electrolyte
An electrolyte is a medium containing ions that is electrically conducting through the movement of those ions, but not conducting electrons. This includes most soluble salts, acids, and bases dissolved in a polar solvent, such as water. Upon dis ...
s. Because of the voltage drop between the Cl
− and Glycine-buffers, proteins are compressed (stacked) into micrometer thin layers.
The boundary moves through a pore gradient and the protein stack gradually disperses due to a frictional resistance increase of the gel matrix. Stacking and unstacking occurs continuously in the gradient gel, for every protein at a different position. For a complete protein unstacking the polyacrylamide-gel concentration must exceed 16% T. The two-gel system of "Laemmli" is a simple gradient gel. The pH discontinuity of the buffers is of no significance for the separation quality, and a "stacking-gel" with a different pH is not needed.
Visualization
The most popular protein stain is
Coomassie brilliant blue
Coomassie brilliant blue is the name of two similar triphenylmethane dyes that were developed for use in the textile industry but are now commonly used for staining proteins in analytical biochemistry. Coomassie brilliant blue G-250 differs from ...
. It is an anionic dye, which non-specifically binds to proteins. Proteins in the gel are fixed by acetic acid and simultaneously stained. The excess dye incorporated into the gel can be removed by destaining with the same solution without the dye. The proteins are detected as blue bands on a clear background.
When more sensitive method than staining by Coomassie is needed silver staining is usually used. Silver staining is a sensitive procedure to detect trace amounts of proteins in gels, but can also visualize nucleic acid or polysaccharides.
Visualization methods without using a dye such as Coomassie and silver are available on the market. For example
Bio-Rad Laboratories markets ”stain-free” gels for SDS-PAGE gel electrophoresis. Alternatively, reversible fluorescent dyes from
Azure Biosystems such as AzureRed or Azure TotalStain Q can be used.
Similarly as in nucleic acid gel electrophoresis, tracking dye is often used. Anionic dyes of a known electrophoretic mobility are usually included in the sample buffer. A very common tracking dye is
Bromophenol blue
Bromophenol blue (3′,3″,5′,5″-tetrabromophenolsulfonphthalein, BPB), albutest is used as a pH indicator, an electrophoretic color marker, and a dye. It can be prepared by slowly adding excess bromine to a hot solution of phenolsulfonpht ...
. This dye is coloured at alkali and neutral pH and is a small negatively charged molecule that moves towards the anode. Being a highly mobile molecule it moves ahead of most proteins.
Medical applications
In
medicine
Medicine is the science and practice of caring for a patient, managing the diagnosis, prognosis, prevention, treatment, palliation of their injury or disease, and promoting their health. Medicine encompasses a variety of health care pract ...
, protein electrophoresis is a method of analysing the
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...
s mainly in
blood serum
Serum () is the fluid and solute component of blood which does not play a role in clotting. It may be defined as blood plasma without the clotting factors, or as blood with all cells and clotting factors removed. Serum includes all proteins not u ...
. Before the widespread use of
gel electrophoresis
Gel electrophoresis is a method for separation and analysis of biomacromolecules ( DNA, RNA, proteins, etc.) and their fragments, based on their size and charge. It is used in clinical chemistry to separate proteins by charge or size (IEF ...
, protein electrophoresis was performed as free-flow electrophoresis (on paper) or as immunoelectrophoresis.
Traditionally, two classes of
blood proteins
Blood-proteins, also termed plasma proteins, are proteins present in blood plasma. They serve many different functions, including transport of lipids, hormones, vitamins and minerals in activity and functioning of the immune system. Other blood pr ...
are considered:
serum albumin
Serum albumin, often referred to simply as blood albumin, is an albumin (a type of globular protein) found in vertebrate blood. Human serum albumin is encoded by the ''ALB'' gene. Other mammalian forms, such as bovine serum albumin, are chemical ...
and
globulin
The globulins are a family of globular proteins that have higher molecular weights than albumins and are insoluble in pure water but dissolve in dilute salt solutions. Some globulins are produced in the liver, while others are made by the immune ...
. They are generally equal in proportion, but
albumin
Albumin is a family of globular proteins, the most common of which are the serum albumins. All the proteins of the albumin family are water-soluble, moderately soluble in concentrated salt solutions, and experience heat denaturation. Albumins ...
as a molecule is much smaller and lightly, negatively-charged, leading to an accumulation of albumin on the electrophoretic gel. A small band before albumin represents
transthyretin
Transthyretin (TTR or TBPA) is a transport protein in the plasma and cerebrospinal fluid that transports the thyroid hormone thyroxine (T4) and retinol to the liver. This is how transthyretin gained its name: ''transports thyroxine and retinol'' ...
(also named prealbumin). Some forms of medication or body chemicals can cause their own band, but it usually is small. Abnormal bands (spikes) are seen in
monoclonal gammopathy of undetermined significance
Monoclonal gammopathy of undetermined significance (MGUS) is a plasma cell dyscrasia in which plasma cells or other types of antibody-producing cells secrete a myeloma protein, i.e. an abnormal antibody, into the blood; this abnormal protein is u ...
and
multiple myeloma
Multiple myeloma (MM), also known as plasma cell myeloma and simply myeloma, is a cancer of plasma cells, a type of white blood cell that normally produces antibodies. Often, no symptoms are noticed initially. As it progresses, bone pain, an ...
, and are useful in the diagnosis of these conditions.
The globulins are classified by their banding pattern (with their main representatives):
* The ''
alpha
Alpha (uppercase , lowercase ; grc, ἄλφα, ''álpha'', or ell, άλφα, álfa) is the first letter of the Greek alphabet. In the system of Greek numerals, it has a value of one. Alpha is derived from the Phoenician letter aleph , whic ...
'' (α) band consists of two parts, 1 and 2:
** α
1 -
α1-antitrypsin, α
1-acid glycoprotein.
** α
2 -
haptoglobin
Haptoglobin (abbreviated as Hp) is the protein that in humans is encoded by the ''HP'' gene. In blood plasma, haptoglobin binds with high affinity to ''free'' hemoglobin released from erythrocytes, and thereby inhibits its deleterious oxidative ...
,
α2-macroglobulin,
α2-antiplasmin,
ceruloplasmin
Ceruloplasmin (or caeruloplasmin) is a ferroxidase enzyme that in humans is encoded by the ''CP'' gene.
Ceruloplasmin is the major copper-carrying protein in the blood, and in addition plays a role in iron metabolism. It was first described in 194 ...
.
* The ''
beta
Beta (, ; uppercase , lowercase , or cursive ; grc, βῆτα, bē̂ta or ell, βήτα, víta) is the second letter of the Greek alphabet. In the system of Greek numerals, it has a value of 2. In Modern Greek, it represents the voiced labiod ...
'' (β) band -
transferrin
Transferrins are glycoproteins found in vertebrates which bind to and consequently mediate the transport of iron (Fe) through blood plasma. They are produced in the liver and contain binding sites for two Fe3+ ions. Human transferrin is encode ...
,
LDL
Low-density lipoprotein (LDL) is one of the five major groups of lipoprotein that transport all fat molecules around the body in extracellular water. These groups, from least dense to most dense, are chylomicrons (aka ULDL by the overall densit ...
,
complement
A complement is something that completes something else.
Complement may refer specifically to:
The arts
* Complement (music), an interval that, when added to another, spans an octave
** Aggregate complementation, the separation of pitch-class ...
* The ''
gamma
Gamma (uppercase , lowercase ; ''gámma'') is the third letter of the Greek alphabet. In the system of Greek numerals it has a value of 3. In Ancient Greek, the letter gamma represented a voiced velar stop . In Modern Greek, this letter re ...
'' (γ) band -
immunoglobulin
An antibody (Ab), also known as an immunoglobulin (Ig), is a large, Y-shaped protein used by the immune system to identify and neutralize foreign objects such as pathogenic bacteria and viruses. The antibody recognizes a unique molecule of the ...
(IgA, IgD, IgE, IgG and IgM).
Paraprotein
A myeloma protein is an abnormal antibody (immunoglobulin) or (more often) a fragment thereof, such as an immunoglobulin light chain, that is produced in excess by an abnormal monoclonal proliferation of plasma cells, typically in multiple myelom ...
s (in multiple myeloma) usually appear in this band.
Normal present medical procedure involves determination of numerous proteins in plasma including hormones and enzymes, some of them also determined by electrophoresis. However, gel electrophoresis is mainly a research tool, also when the subject is blood proteins.
See also
*
Affinity electrophoresis
Affinity electrophoresis is a general name for many analytical methods used in biochemistry and biotechnology. Both qualitative and quantitative information may be obtained through affinity electrophoresis. The methods include the so-called electr ...
*
Electroblotting
Electroblotting is a method in molecular biology/biochemistry/ immunogenetics to transfer proteins or nucleic acids onto a membrane by using PVDF or nitrocellulose, after gel electrophoresis. The protein or nucleic acid can then be further anal ...
*
Electrofocusing
Isoelectric focusing (IEF), also known as electrofocusing, is a technique for separating different molecules by differences in their isoelectric point (pI). It is a type of zone electrophoresis usually performed on proteins in a gel that takes ad ...
*
Polyacrylamide gel electrophoresis, PAGE, or gel electrophoresis
*
Immunoelectrophoresis
Immunoelectrophoresis is a general name for a number of biochemical methods for separation and characterization of proteins based on electrophoresis and reaction with antibodies. All variants of immunoelectrophoresis require immunoglobulins, a ...
*
Immunofixation Immunofixation permits the detection and typing of monoclonal antibodies or immunoglobulins in Blood serum, serum or urine. It is of great importance for the diagnosis and monitoring of certain blood related diseases such as myeloma.
Principle
T ...
*
SDD-AGE
In biochemistry and molecular biology, SDD-AGE is short for Semi-Denaturating Detergent Agarose Gel Electrophoresis. This is a method for detecting and characterizing large protein polymers which are stable in 2% SDS at room temperature, unlike ...
*
Native gel electrophoresis
*
QPNC-PAGE
QPNC-PAGE, or quantitative preparative native continuous polyacrylamide gel electrophoresis, is a bioanalytical, high-resolution and highly accurate technique applied in biochemistry and bioinorganic chemistry to separate proteins quantitatively ...
*
Paraprotein
A myeloma protein is an abnormal antibody (immunoglobulin) or (more often) a fragment thereof, such as an immunoglobulin light chain, that is produced in excess by an abnormal monoclonal proliferation of plasma cells, typically in multiple myelom ...
*
Fast parallel proteolysis (FASTpp)
References
External links
Educational resource for protein electrophoresisGel electrophoresis of proteins
{{Electrophoresis
Electrophoresis
Molecular biology
Protein methods
Laboratory techniques
Blood tests