Fluorescent Dye based Exosome Labeling Service

Overview Services Features FAQs

Overview

Exosomes, as nano-scale particles, need to be labeled to observe the traces of exosomes in vivo and in vitro. For the study of exosome function, it is generally necessary to observe whether the corresponding phenotypic indicators in the recipient cells, tissues, or organs change after the exosomes are taken up by the recipient cells or reach the target tissues and organs. Therefore, exosome labeling is the basis and key step for the study of exosome function. Creative Biolabs has a complete technical platform and rich service experience and can provide a variety of commonly used fluorescent dyes for labeling exosomes, including carbocyanine dyes, PKH dyes, and penetrant dyes.

In the exosome-related articles published so far, most of the exosomes are labeled with lipophilic dyes. The specific labeling principle is that the lipophilic fluorescent dye embeds its aliphatic tails into the phospholipid biomolecules of exosomes in a non-covalent manner, thereby emitting a stable and long-lasting strong fluorescent signal.

Tab. 1 Dyes for Labeling Exosomes

Category	Dyes	Characteristics	Mechanism of Action	Application
Lipophilic Carbocyanine Dyes	DiL, DiR, DiO, DiD	High extinction coefficient, polarity dependence, short excited state lifetime; clean background to avoid interference from autofluorescence in the visible range	After entering the exosome membrane, the dyes diffuse and label the entire membrane structure, significantly enhancing fluorescence intensity	Labeling cell membranes and other lipid-soluble biological structures
Lipophilic PKH Dyes	PKH-67, PKH-26	Low toxicity, low fluorescence background, high fat solubility, strong penetrability, strong and stable fluorescence; PKH-67 has a fluorescent half-life of 10-12 days in vivo, PKH-26 can last up to 100 days or more	PKH dye molecules have long aliphatic tails that insert into the phospholipid bilayers while the fluorophores stay outside the exosome membrane and emit strong fluorescence	Labeling exosomes
Penetrating Dyes	CFSE, Calcein-AM	CFSE is colorless and non-fluorescent itself; Calcein-AM increases hydrophobicity by introducing AM groups	CFSE reacts with intracellular amino groups after esterases remove the acetate group, forming a stable fluorescent conjugate; Calcein-AM is cleaved by esterases to form impermeable Calcein, emitting strong green fluorescence	Detecting the integrity of exosomes

Tab. 2 Excitation and Emission Wavelengths of Commonly Used Fluorescent Dyes

Fluorescent dyes	Observed Color	Marked location	Excitation Wavelength	Emission Wavelength
DiO	Green	Intramembrane	484 nm	501 nm
DiL	Orange	Intramembrane	549 nm	565 nm
DiD	Red	Intramembrane	644 nm	665 nm
DiR	Deep Red	Intramembrane	750 nm	780 nm
PKH-67	Green	Extramembrane	484 nm	501 nm
PKH-26	Red	Extramembrane	551 nm	567 nm
CFSE	Green	Inside	494 nm	521 nm
Calcein-AM	Green	Inside	490 nm	515 nm

Services

The above-mentioned commonly used fluorescent dyes for labeling exosomes can be used for in vivo and in vitro functional studies of exosomes, such as exosome tracking services such as exosome labeling, in vitro cell uptake, and in vivo animal imaging. Creative Biolabs has launched various exosome dye products and exosome tracing services. You can contact us to put forward your needs according to your research purposes. We will make the most suitable plan for you.

DiO-labeled exosomes were uptaked by HEK 293T cells. (Creative Biolabs Original) Fig.1 Exosomes labeled using the DiO-Membrane EVs Labeling & Purification Kit (green) (Cat.# ELP-01) were internalized by HEK 293T cells.

Features

Diverse dye selection
Efficient labeling technology
High-quality fluorescence imaging
Strict experimental procedures

FAQs

Q: How does your technical service ensure the activity of exosomes during the entire labeling process?

A: We use optimized labeling techniques and strict experimental procedures to protect the integrity of the exosomes to the greatest extent possible.

Q: What research applications can labeled exosomes be used for?

A: Labeled exosomes can be used in various research applications, such as flow cytometry, cell uptake experiments, and in vivo and in vitro tracking. Our labeling service is designed to provide reliable tools and data support for your research.

Q: What sample quantity and volume can you handle?

A: We can handle samples of various scales, from small experimental batches to large-scale samples. The required sample volume will depend on the specific experimental design and labeling needs.

Q: What should customers do before submitting samples?

A: We will provide you with detailed sample preparation guidelines, including specific requirements for sample collection, storage, and transportation. Ensuring sample quality is crucial for achieving optimal labeling results.

Q: Are labeled exosomes suitable for in vivo experiments?

A: Yes, labeled exosomes can be used for in vivo experiments, such as exosome tracking and distribution studies in animal models. To avoid interference from tissue autofluorescence, it is recommended to use red dyes, such as DiD, DiR, and PKH-26.