Fluorescent labeled peptides can be used to identify specific targets after combining with imaging technology. Confocal or fluorescence microscopy in vitro imaging is still the study of various biological processes and phases in cells.

One of the most effective methods of interaction. Unlike proteins, these peptides are located at specific targets on actin and are not easy to aggregate proteins, so they are very suitable for
In vitro tracking. Similarly, FITC-labeled CPP can also be used for imaging of intracellular components, and its cytotoxicity is low.
Among them, FITC is an amine-active fluorescent dye that can be widely used to label peptides and proteins. Synbiotics label Fitc at the N-terminus, and it is recommended to follow
An alkyl spacer such as aminocaproic acid (Ahx) is introduced between each amino group and the thiourea bond produced by the reaction of isothiocyanate and amino group. Link cutting
An acidic environment is required. The peptides labeled with FITC at the N-terminus need to undergo cyclization to form fluorescein, usually accompanied by the removal of the latter amino acid, but when there is one
This situation can be avoided when spacers such as aminocaproic acid, or when the peptide of interest is cut from the resin through a non-acidic environment. Steric hindrance is considered to be a fluorescent dye
The main reason for using Ahx before feeding is not the reason why FITC cannot be directly coupled to the peptide.

For longer sequences, it is recommended to use FRET pairs (fluorescence resonance energy transfer pairs) for modification.
Fluorescence resonance energy transfer (FRET) is a mechanism that describes the energy transfer between two fluorophores. Since FRET efficiency is partly based on the relationship between the donor and acceptor molecules
Distance, so this technique is often used to study enzyme efficiency, protein-protein interaction or other molecular dynamics.





Figure 1. FRET mechanism for protease research.
(When the peptide remains intact, the acceptor molecule will quench the donor molecule, and fluorescence will not be detected. If the sequence is cleaved by protease activity, the acceptor will no longer be quenched
Donor, and fluorescence signal will be detected)






FRET peptide is a convenient tool for studying the specificity of peptidase. Because the reaction process can be continuously monitored, it provides a convenient method for the detection of enzyme activity.
The fluorescence produced by the hydrolysis of the peptide bond of the donor/acceptor pair can be used to measure the enzyme activity at nanomolar concentrations. When the FRET peptide is intact, it shows the internal fluorescence burst
However, when any peptide bond of the donor/acceptor pair is broken, fluorescence will be released. This fluorescence can be continuously detected, so that the enzyme activity can be quantitatively analyzed.
FRET peptides can be used as suitable substrates for various enzyme research, such as:
1. The dynamic and functional characteristics of peptidases, proteases, kinases, and phosphatases.
2. Screening and testing of new proteolytic enzymes.
3. Research on the conformation of polypeptide folding.

Warm tips: Suzhou Beike nano products are only used for scientific research, not for human body,different batches of products have different specifications and performance

Message

Name： * Mobile： * E-mail： * Content：

Scan code concerns WeChat official account QQCommunication group：1092348845

Warm tips: Suzhou Beike nano products are only used for scientific research, not for human body,different batches of products have different specifications and performance.The website pictures are from the Internet. The pictures are for reference only. Please take the real object as the standard. In case of infringement, please contact us to delete them immediately.