Fluorescent Isothiocyanate (FITC) Labeling Services

Service Description

Fluorescent isothiocyanate (FITC) labeling is a powerful technology that is widely used in a variety of scientific applications, particularly in the fields of molecular biology, immunology and biochemistry. FITC is commonly used to bind fluorescent dyes to biological molecules such as proteins, peptides, antibodies, and nucleic acids, allowing real-time tracking and detailed analysis of these molecules in complex systems. BOC Sciences provides high-quality FITC labeling services to meet the needs of researchers and pharmaceutical companies.

FITC-siRNA hybrids with sense-strand modifiers. (Kozuch S D., 2018)

What is fluorescein isothiocyanate (FITC)?

FITC is a small-molecule organic compound that can bind to various antibody proteins. After binding, the antibody does not lose its specificity in binding to certain antigens and still has strong green fluorescence in alkaline solutions. After adding acid, precipitate is precipitated, the fluorescence disappears, and it is slightly soluble in acetone, ether and petroleum ether.

What is FITC labeling?

FITC labeling involves binding the fluorescent dye fluorescein isothiocyanate to amine-containing molecules. Ideal as a probe for a variety of laboratory techniques such as flow cytometry, immunofluorescence and protein detection, during the labeling process, the isothiocyanate group of FITC reacts with primary amines to form a stable thiourea bond. As the fluorescent dye of choice in fluorescence-activated cell sorting (FACS), FITC reacts with the lysine residues of the antibody to label the antibody. The standard coupling strategy is to couple 3 to 6 FITC molecules per antibody molecule to avoid solubility and fluorescence brightness problems caused by too high ratios. The optimal labeling conditions were selected by comparing the antibody brightness and background at different FITC ratios. FITC has an excitation wavelength of 488 nm and an emission wavelength of 530 nm, which makes it useful for precise detection and quantification of cellular markers in FACS analysis. The optimized FITC labeling technology ensures high contrast and low background fluorescence signals in experiments.

FITC labeling protocol

FITC (fluorescein isothiocyanate) labeling is a technology for fluorescent biomarkers that bind to biomolecules such as proteins and antibodies to produce fluorescence for microscopy or flow cytometry analysis. Here is an overview of a typical FITC marking protocol:

Material preparation: First, tools such as FITC reagents, proteins or antibodies to be labeled, buffers (such as PBS buffers), and centrifugal filters need to be prepared. Make sure all reagents are fresh to ensure the marking effect.

Solution preparation: Dissolve the FITC in a suitable solvent, usually DMSO. This process should be carried out under dark conditions to prevent the FITC from breaking down due to light.

Treatment of proteins or antibodies: The protein is dissolved in a suitable buffer, usually a carbonate buffer with a pH of 8.0-9.0, as needed. This pH helps to improve the efficiency of FITC binding to proteins.

Reaction process: Mix the FITC solution with the protein solution, usually in accordance with a certain molar ratio (such as FITC: protein =1:1 to 10:1). This mixing needs to be done at room temperature and away from light, usually for 1-2 hours, in order for the marking to be fully completed.

Removal of unbound FITC: Unbound FITC molecules are removed by techniques such as dialysis or column chromatography to avoid affecting subsequent experimental results.

Confirmation of labeling efficiency: The labeling efficiency of FITC can be confirmed by detecting the labeled protein solution with an ultraviolet spectrophotometer, and the typical absorption peak appears at 495 nm. The analysis is generally based on fluorescence intensity or through SDS-PAGE.

Storage: The labeled product should be stored away from light at a low temperature (e.g. 4 °C) to maintain its activity and fluorescence intensity.

Once labeled, the resulting FITC-protein complex can be used in a variety of fluorescence imaging analyses to further understand the function and behavior of biomolecules.

Applications of FITC labeling

FITC labeling finds widespread use across various scientific and clinical applications due to its ability to enable highly sensitive and specific detection of biomolecules.

Flow cytometry

Flow cytometry is one of the most common applications of FITC labeling. In this technique, FITC-labeled antibodies or cells are passed through a laser beam, and the fluorescence emitted by the FITC label is detected. This allows for precise analysis of cell populations, receptor expression, and cellular events. BOC Sciences provides FITC labeling services for antibodies and cell markers used in flow cytometry, enabling accurate data collection and analysis.

Immunofluorescence microscopy

FITC labeling is widely used in immunofluorescence microscopy to visualize the location of specific proteins or molecules within cells or tissues. The high fluorescence intensity of FITC allows for clear imaging of cellular structures, enabling researchers to track protein localization, gene expression, and cell signaling pathways.

Apoptosis detection

FITC is frequently used in assays designed to detect apoptosis, such as the Annexin V-FITC assay. In this application, FITC-conjugated annexin V binds to phosphatidylserine on the surface of apoptotic cells, allowing for easy detection using flow cytometry or fluorescence microscopy.

Receptor-mediated targeting

FITC labeling is also used in studies involving receptor-mediated drug delivery. By labeling drug carriers or targeting molecules with FITC, researchers can track the cellular uptake and distribution of these compounds in vitro and in vivo, providing valuable insights into the effectiveness of targeted therapies.

Protein-protein interaction studies

FITC labeling enables the study of protein-protein interactions by tagging one protein of interest with FITC and detecting interactions with other labeled molecules. This approach can be combined with techniques like surface plasmon resonance (SPR) or co-immunoprecipitation to gain deeper insights into molecular interactions.

Enzyme activity assays

FITC labeling is also used in enzyme activity assays, where FITC-labeled substrates are incubated with target enzymes. The fluorescence emission from FITC allows for the monitoring of enzyme activity in real-time, providing valuable information about enzyme kinetics and substrate specificity. This application is used in drug screening, enzyme inhibitor studies, and metabolic pathway analysis.

Advantages of FITC labeling

High sensitivity: FITC's high quantum efficiency ensures that even low concentrations of the labeled biomolecule can be detected with high sensitivity. This makes it particularly useful for applications that require precise measurements, such as flow cytometry or quantitative PCR.

Non-radioactive: Unlike traditional radioisotope labeling, FITC labeling does not require special handling, disposal, or regulatory compliance, making it a safer and more convenient alternative for researchers.

Versatility: FITC can be used to label a wide variety of biomolecules, including proteins, peptides, nucleic acids, and antibodies. Its versatility makes it suitable for a broad range of applications in molecular biology, immunology, and drug development.

Brightness and stability: FITC exhibits strong fluorescence and remains stable under a wide range of experimental conditions, allowing for reliable results across multiple assays.

FITC labeling services at BOC Sciences

BOC Sciences offers a comprehensive suite of FITC labeling services to support research and development efforts in various scientific fields. Our expert team is equipped with state-of-the-art facilities and years of experience to provide high-quality, customized FITC labeling solutions. We offer the following services:

Protein and enzyme FITC labeling: FITC acts as a fluorescent probe to react with an amino group on the amino acid side chain of a protein or enzyme to form a stable covalent binding. This process allows researchers to observe and track the movement, position and interactions of these biomolecules through fluorescence microscopy or fluorescence metrology techniques.

Peptide and antibody FITC labeling: BOC Sciences provides FITC labeling services for peptides, antibodies, and other biomolecules, enabling precise detection in various assays.

Cellular FITC labeling: FITC can be used to label cells for flow cytometry, imaging, and apoptosis detection. We assist researchers in tracking cellular processes and receptor-mediated targeting.

Nucleic acid FITC labeling: BOC Sciences offers custom FITC labeling for nucleic acids, including DNA, RNA, and oligonucleotides, ensuring optimal conjugation that does not compromise the integrity or stability of the nucleic acid. We work with various types of oligonucleotides, including primers, probes, and synthetic genes, to provide FITC-labeled molecules with ideal fluorescence for your specific application. The FITC-to-nucleic acid ratio is typically kept at 1:10 to 1:15, balancing strong fluorescence signals with the preservation of nucleic acid functionality for applications like PCR amplification and gene knockdown assays.

Biotin, avidin and lectin FITC labeling: Biotin is a small molecule that binds avidin proteins with high efficiency. Lectins are proteins that specifically recognize and bind to sugar molecules. By tagging FITCs to these molecules, researchers can track and locate them in complex biological systems, studying their functions and interactions. Fitc-labeled molecules emit green fluorescence under ultraviolet or blue excitation, which provides an effective means for molecular visualization and quantitative analysis.

Custom FITC labeling services: We offer flexible and tailored FITC labeling services to meet the unique needs of your project. Whether you need high-throughput labeling or specialized conjugation, BOC Sciences is your trusted partner.

Separation and purification of FITC-labeled biomolecules: To ensure that only FITC-conjugated biomolecules are used in downstream applications, we provide comprehensive purification services, including dialysis, size-exclusion chromatography, and affinity chromatography. These methods are highly effective in removing unreacted FITC, ensuring that your samples are free from contamination that could affect experimental outcomes. The purification process is optimized based on the size and nature of the biomolecule, and we use molecular weight cutoffs ranging from 3 kDa to 50 kDa to select the most suitable purification strategy for your sample.

Our services advantages

Expertise and experience: With over 20 years of experience in the pharmaceutical and biotechnology industries, BOC Sciences ensures that your FITC labeling project is handled by highly trained professionals.

Customization: We provide tailored labeling services, adapting the protocol to your specific biomolecule and application requirements.

High quality: We adhere to strict quality control protocols, ensuring that each FITC-labeled product meets the highest standards of purity, efficiency, and reproducibility.

Timely delivery: Our efficient processes and state-of-the-art facilities allow us to deliver results on time, helping you stay on track with your research and development timelines.

Quality Services

Resources

FITC Conjugated Antibody

FITC labeled siRNA

FAQ

1. What types of biomolecules can be labeled with FITC?

FITC can be used to label a wide range of biomolecules, including proteins, peptides, antibodies, nucleic acids, and other amine-containing compounds.

2. Is FITC labeling safe?

Yes, FITC labeling is non-radioactive and does not pose significant safety concerns. However, as with any chemical reagent, it is important to follow proper handling and disposal procedures.

3. Can FITC labeling be used for in vivo applications?

Yes, FITC labeling can be used for in vivo studies, particularly in receptor-mediated targeting, drug delivery, and cellular tracking experiments.

4. What is the shelf life of FITC-labeled products?

FITC-labeled products should be stored in a dark, cool place to maintain their fluorescence stability. When stored properly, they can remain functional for several months.