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The polypeptide is stable at-20 ℃, in particular, freeze dried and kept in a desiccator, before they are exposed to air, freeze dried peptides can be kept at room temperature. It will be the humidity effects, cannot be frozen when dry, the best method is based on small sample volume deposited.
for Cys, Met orTrP peptide, and reducing buffer solution is essential, because this peptide can be prone to oxidation, in front of the bottle, slowly through the peptide nitrogen or argon gas reduces oxidation. Gln and Asn-containing peptides are easily degradable, all of these peptides and peptide which do not contain Glycoside solutions to these problems than, lifetime is limited.
polypeptide solubility preferred solvent for most of the peptide is ultra pure water. Dilute acetic acid or ammonia respectively for alkaline or acid-dissolution of the peptide is very important. These methods are not soluble polypeptide, requires DMF, urea, guanidiniam chloride or acetonitnle to dissolve these solvents may be some experiments have side effects. So we propose to design peptides to attention. Ala
residues, Cys, Ile, Leu, Met, Phe, and Val will increase the difficulty of the dissolution of the peptide.
unique peptides, or any technical help you need, please feel free to contact us. We package your complete satisfaction, we cannot adequately synthesize the order, we do not charge. Save, and actions of the peptide
packaging 1mg or fewer peptides by net weight packaging, vials of the statement does not contain ions and water resistance. For example, the amino acid peptide analysis decisions are 80%, in the 1mg sample, the gross weight is 1.25mg in a bottle.
large number of peptides with gross weight calculation. Mark weight of ions and water resistance, for example, 25mg peptides in the sample is 90%, then the effective peptides for 25mgx90%=22.5mg
don't put the peptide content and purity mixed up. Purity of peptides may be 100%, and peptide electriferous (Arg, Lys) resistance of ions and peptide hydrophilic decision. This is the characteristics of synthetic peptides. Preservation of freeze-dried peptide
all products should be stored in a refrigerator, best of-20 degrees Celsius. Most peptides can be stored for years in this way does not change. Peptide solution saves
peptide solution than freeze dried form is not stable, the solution is neutral pH (pH5-7),-20 ℃ to save, in order to avoid repeated freezing and thawing of the samples, best divided into small storage. A sample is not used after thawing, should be got rid of, bacterial degradation of peptide trouble sometimes become solution, in order to overcome this, peptides should be dissolved in sterile water, or peptide solution 0.2 µm membrane filter.
polypeptide reconstruction and operation
most of the peptide dissolved in sterile distilled water. Solution for the first time, pay attention to the initial concentration for concentration, if peptide only a limited solubility, it allows other solvents or buffer salt.
If more peptide in water in the of dissolved sex limited, has several select can help dissolved:
on alkaline peptide with dilute acetic acid (containing Arg, Lys, His)
acid peptide with dilute ammonia (containing Asp, Glu)
on very sparse water of peptide with 10% organic modified real (Acetonitnile, Methanol)
very not dissolved of peptide with DM50 or DMF
guanicline Concentrated solution of the hydrochloride or urea is also useful, combined with above methods, are also effective means of dissolving peptides.
polypeptides and save
polypeptide with a wide range of solubility. Insoluble peptide secondary structure formation are the main problems. Except for the outside too peptide, it will happen, there would be multiple hydrophobic residues in the peptide significantly. Salt can promote the formation of secondary structures. We recommend first dissolved in sterile distilled water or deionized peptides. Such as the need to increase the solubility, acoustic treatment available. Dissolved still have problems, add a small amount of dilute acetic acid (10%) or ammonia will dissolve.
to the long-term preservation of peptides, it is best to freeze drying, cold dry powder at-20 ℃ or less stored years with little or no degradation. Peptides in aqueous solution is far less stable. Peptides are vulnerable to degradation by bacteria, sterile purified water to dissolve.
Met, Cgs or Try residues in the peptide solution due to oxidation, a limited life span. No oxygen dissolved in solvent, in order to prevent repeated freeze-thaw damage, it is recommended that dissolved large amounts of peptide experiment, save the remaining polypeptide in solid form. Analysis and purification of

HPLC Analysis of HPLC columns and pumps, high pressure can be passed through, it can be used to very fine particles (3-10 μ m) stuffing. This peptide to height was analyzed in a few minutes.
two types of HPLC ion exchange and reverse-phase. Ion-exchange HPLC rely on direct charge and solid phase peptide interactions. Column with a specific charge become a certain range of PH ion, polypeptides or peptide mixture, by its amino acid composition showed an opposite charge. Separation is a charge interaction through variable PH, ionic strength, or both peptides eluted, typically with low ionic strength solution first, then gradually strengthen or step by step strengthened until the peptides eluted in the pillar. An example of an ion-exchange separation using a strong cation exchange column. Sulfoethylaspartimide separated by positively to acid PH.
by reversed-phase HPLC and chromatography normally is the opposite. Peptide by hydrophobic interactions on the connected to column, wash off with lower ionic strength, such as increasing the hydrophobicity of the eluent. Usually posts by Covalent adsorption of hydrogen and carbon to Silicon alkyl chains, the chain length G4-G8 carbon atoms. As Elution is a hydrophobic interactions. Long chain post than a short chain of small, high-charged peptides better. On the larger hydrophobic peptide with short column Elution well. However, the general practice, these two types of column interconversion is not significantly different, alternative carriers formed by carbohydrates, such as phenyl.
typical operations are often made up of two Ribbon granules, 0.1%TFA-H2o and 80% acetonitrile 0.1%TFA--H2o sparse acetonitrile. Linear gradation mix with 0.5% to 1% per minute to change speed. Common analysis and purification in columns for 4.6x250mm (3-10 μ m) and 22x250mm (10 μ m). If you fill the column with radial, then size is 8x100 (3-10 μ m) and 25x250mm (10 μ m)
a large number of various buffers containing many different reagents, such as heptafluorobutyric acid, 0.1% acid, dilute He formic acid (5-6%, pH2-4), 10-100mM NH4HCO3, sodium acetate/spandex, TFA/TEA, sodium or potassium, isoprene forms. So many different combinations to form a buffer, but be aware: reversed-phase column Silicon material long exposure to high pH or slightly alkaline pH, as this would undermine the pillars.