Peptide Purity Levels and Applications
Bio-Synthesis provide several different purity levels to help our client to make right choice for their research applications.

A >75% pure peptide is usually sufficient for generating or testing antibodies. A mixture of closely related peptides is usually able to induced an immune response that will provide the required antibody. However, the presence of impurities which inherit during organic synthesis process can be the source of adverse side effects like inflammatory or even toxic effects during the antibody production procedure. Therefore, our immunograde peptides always undergo a special treatment for complete extraction of organic impurities by undergo our stand purification process.

For enzymology or biological activity studies, a peptide with >85% or 95% is usually required. Thess levels of peptides must go through quality control by reversed phase HPLC and MALDI-TOP mass spec analysis, some times, amino acid analysis, even sequencing is also available.

What kind of impurities found in Crude-Desalted Peptides?
Truncated sequences
Deleted sequences
Incomplete deprotected sequences
Sequences modification during peptide cleavage process
DTT (dithiothreitol)
TFA (trifluoroacetic acid)
Acetic Acid
Side reaction due to proline isomerization or isoaspartimide formation, etc.
What kind of impurities found in Crude-Desalted Peptides?
Deleted sequences
Truncated sequences
Incomplete deprotected sequences
Sequences modification during cleavage porcess
TFA (trifluoroacetic acids
Peptide undergo side reactions such as porline isomerization or aspartimides formations etc.
APPLICATIONS:
What kind of impurities found in Crude-Desalted Peptides?
These peptides are recommend for fist pass/fail screening applications where large numbers of peptides must be tested. Once the initial good screening have been identified, a second screening with more highly purified peptide is recommended. The applications will be:
Epitope mapping
Protein to protein interactions
Immunogenic identification
Receptor-ligand interactions
Nucleic acid binding
Mutation Screening
Sequence optimization
>75% Pure Immunograde
The applications use in our >75% pure peptide will be:
Sequence specific polyclonal antibodies productions.  As the amount of contaminating peptide species is very low, the antigenic response to these will be small.  Sequence selection will play an important role in antibody specificity than the cross-reactivity from contaminating peptides.
The antibody titer using ELISA do not require higher purity peptides than >75% pure.
Affinity purification of polyclonal antibodies
>85% Biochemistry grade
The applications recommended to be used in >85% pure peptide will be:
Peptide blocking studies (non-quantitative)
In-vitro bioassays
Coating tissue culture plates for cell attachment studies
Semi-quantitative enzyme-substrate studies
Phosphorylation reactions
Polyclonal Antibody Production
Protein electrophoresis applications
Coupling to chromatography resins for affinity purifications
90% to >95% Purity
Quantitative Receptor-ligand interaction
In vitro bioassays
In vivo studies
Quantitative blocking and competitive inhibition assays
Quantitative phosphorylation studies
NMR studies
physical properties standards
Structural studies
Enzyme studies
Monoclonal antibody production