Precision Labeling Technology

Site-Specific Protein Labeling Services

Achieve precise, homogeneous protein labeling with our advanced site-specific technologies. Eliminate heterogeneity and ensure consistent 1:1 stoichiometric conjugation at predefined positions for your research and therapeutic applications.

1:1 Stoichiometry

MS Verified

Multiple Platforms

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Trusted by leading research and pharmaceutical institutions

Harvard

Pfizer

MIT

Roche

Stanford

Novartis

Why Choose Us

1:1 labeling ratio guaranteed

>95% labeling efficiency

Multiple tag systems available

Expert consultation included

Enzyme-Mediated Tags

SNAP-tag, CLIP-tag, HaloTag systems

Peptide Tag Systems

SpyTag, SnoopTag, isopeptide bonding

Bioorthogonal Chemistry

Azide-alkyne click, strain-promoted reactions

Labeling Efficiency

>95%

Service Overview

Precision Labeling for Consistent Results

Our site-specific protein labeling services eliminate the heterogeneity associated with traditional random labeling methods.

1:1 Stoichiometric Ratio

Every protein molecule gets labeled at exactly one predefined position. No mixture of singly, doubly, or un-labeled species. Consistent batch-to-batch quality guaranteed.

Homogeneous conjugates
Precise stoichiometry
Reproducible results

Preserve Protein Function

Labels are placed away from active sites and binding interfaces. Your protein retains full biological activity after conjugation for accurate functional studies.

Active site protection
Full biological activity
Structural integrity

Multiple Platforms

Choose from enzyme-mediated tags, bioorthogonal chemistry, or genetic code expansion. We match the right technology to your specific experimental requirements.

SNAP-tag, HaloTag
Click chemistry
Unnatural amino acids

Mass Spec Verified

Every batch verified by ESI-MS for labeling efficiency and position confirmation.

High Efficiency

Standard >95% labeling efficiency ensures optimal conjugate yield.

Flexible Scale

From 0.1 mg analytical scale to gram-scale commercial production.

Full QC Package

SDS-PAGE, MS analysis, and Certificate of Analysis included.

Technology Platform

Advanced Labeling Technologies

Industry-leading platforms for precise, covalent protein modification.

Enzyme-Mediated Tags

Self-labeling protein tags that covalently attach to customized substrates with tunable specificity for various applications.

SNAP-tag CLIP-tag HaloTag

Covalent, near-irreversible binding
Multiple orthogonal systems
Wide substrate compatibility

Peptide Tag Systems

Short peptide tags that spontaneously form covalent isopeptide bonds with their cognate catcher proteins.

SpyTag/SpyCatcher SnoopTag

Complete reaction in 15-60 min
No catalyst required
High yield under mild conditions

Bioorthogonal Chemistry

Azide-alkyne click chemistry and strain-promoted cycloadditions for chemoselective labeling with zero cross-reactivity.

Azide-Alkyne Click SPAAC

Exceptional chemoselectivity
Works in complex biological mixtures
Compatible with live cells

Genetic Code Expansion

Incorporation of unnatural amino acids bearing bioorthogonal handles at the genetic level for true single-site precision.

Unnatural Amino Acids p-Acetylphenylalanine

True single-position labeling
Minimal tag size (~200 Da)
Applicable to any protein

Specifications

Flexible Options for Diverse Needs

Comprehensive specifications to meet your research requirements.

Parameter	Options Available
Label Types	Fluorophores (FITC, Cy3, Cy5, Alexa Fluor series), Biotin, HRP, Alkaline Phosphatase, His-tag, FLAG-tag
Tag Systems	SNAP-tag, CLIP-tag, HaloTag, SpyTag/SpyCatcher, SnoopTag, AviTag, His-tag
Protein Types	Antibodies, Enzymes, Receptors, Structural Proteins, Fusion Proteins
Expression Systems	E. coli, Yeast, Insect Cells, Mammalian Cells (HEK293, CHO)
Purity Requirements	Research Grade (>85%), High Purity (>95%), GMP Grade (per request)
QC Analysis	SDS-PAGE, Mass Spectrometry (ESI-MS), HPLC, MS-based Labeling Efficiency
Scale Range	Analytical (0.1-1 mg), Research (1-100 mg), Pilot (100 mg - 1 g), Commercial (g+)

1:1

Labeling Stoichiometry Guaranteed

>95%

Labeling Efficiency Standard

Verified on Every Batch

Workflow

Streamlined Process from Design to Delivery

Our proven 6-step workflow ensures quality and efficiency at every stage.

Consultation

Review protein and recommend labeling strategy

Site Selection

Identify optimal labeling position

Cloning

Tag integration at designated position

Expression

Recombinant protein production

Labeling & QC

Conjugation and MS verification

Delivery

Shipment with Certificate of Analysis

Applications

Versatile Solutions Across Research Areas

Our site-specific labeling services support research and development in multiple fields.

Live Cell Imaging Applications

Track protein movement and localization in real-time with minimal perturbation. Our small tags maximize imaging resolution for super-resolution microscopy applications.

Protein trafficking studies
Super-resolution microscopy
Multiplex imaging with orthogonal tags
Live cell dynamics tracking

1:1

Precise labeling for accurate imaging

Therapeutic Development

Site-specific labeling ensures consistent drug-to-antibody ratios for ADC development. Batch-to-batch consistency is critical for regulatory approval and clinical success.

Antibody-drug conjugates (ADCs)
Bispecific antibodies
Radiopharmaceuticals
Fc-fusion proteins

>95%

Labeling efficiency for therapeutics

Diagnostic Development

Consistent labeling improves assay reproducibility and sensitivity for diagnostic applications. Defined conjugates ensure reliable performance in point-of-care devices.

ELISA development
Flow cytometry reagents
Lateral flow assays
Immunohistochemistry

Consistent

Batch-to-batch reproducibility

Structural Biology

Minimal tag footprint reduces interference for high-resolution structure determination. Precise label placement is critical for accurate distance measurements in FRET studies.

Cryo-EM studies
FRET distance measurements
HDX-MS analysis
EPR spectroscopy

Minimal

Tag footprint for structural studies

Testimonials

What Our Clients Say

Trusted by researchers worldwide for quality and reliability.

"The 1:1 labeling ratio transformed our FRET experiments. No more accounting for heterogeneous conjugates in our analysis. The batch consistency is remarkable."

Principal Scientist

Structural Biology Laboratory

"Site-specific ADC generation was a game-changer for our oncology program. The batch consistency is remarkable and the QC data is comprehensive."

Research Director

Pharmaceutical Company

"We achieved single-molecule resolution in live cells thanks to the minimal tag footprint. The consultation team was extremely helpful in site selection."

Principal Investigator

Cell Biology Research Institution

Scientific Literature

Scientific Foundation

Our platform is backed by peer-reviewed research.

45 Citations

Affinity-Directed Site-Specific Protein Labeling and Its Application to Antibody-Drug Conjugates

Kim S, Lee SW, Yi H, et al. Advanced Science. 2024.

Novel traceless affinity-directed labeling method using small binding proteins and genetic code expansion for site-specific ADC preparation.

View DOI

28 Citations

Site-Specific Proximity Labeling at Single Residue Resolution for Identification of Protein Partners

Bartholow TG, Burroughs P, Elledge SK, et al. bioRxiv. 2023.

High-resolution site-specific proximity labeling method using iridium-based photocatalysts for protein partner identification.

View DOI

87 Citations

Segmental and Site-Specific Isotope Labelling Strategies for Structural Analysis of Posttranslationally Modified Proteins

Vogl DP, Conibear AC, Becker CFW, et al. RSC Chemical Biology. 2021.

Review of chemical and enzymatic tools for site-specific isotope labeling of post-translationally modified proteins for NMR and structural analysis.

View DOI

62 Citations

Ultrafast Bioorthogonal Spin-Labeling and Distance Measurements in Mammalian Cells

Jana S, Evans EGB, Zhang S, et al. Journal of the American Chemical Society. 2023.

Systematic evaluation of bioorthogonal non-natural amino acid incorporation for site-specific labeling in live mammalian cells.

View DOI

34 Citations

Development of a New DHFR-Based Destabilizing Domain with Enhanced Basal Turnover and Applicability in Mammalian Systems

Nakahara E, Mullapudi V, Collier GE, Joachimiak LA, Hulleman JD. ACS Chemical Biology. 2022.

Development of a novel DHFR-based destabilizing domain with enhanced basal turnover and broad applicability as a chemical biology tool for gene therapy.

View DOI

FAQ

Frequently Asked Questions

Find answers to common questions about our service.

What is the difference between site-specific and random labeling?

Random labeling (e.g., lysine or cysteine modification) produces a heterogeneous mixture where each protein molecule may have zero, one, two, or more labels attached at various positions. Site-specific labeling ensures every protein molecule has exactly one label at a predetermined position. This homogeneity improves assay reproducibility, preserves protein function, and enables quantitative studies like FRET.

How do I choose the right labeling position on my protein?

Our scientific team will work with you to analyze your protein structure and identify optimal labeling sites. Key considerations include: avoiding active sites and binding interfaces, ensuring solvent accessibility, selecting flexible regions for minimal structural perturbation, and positioning away from post-translational modification sites.

What labeling technologies do you offer?

We offer multiple orthogonal labeling platforms: SNAP-tag/CLIP-tag systems for dual-color imaging, SpyTag/SpyCatcher for rapid catalyst-free conjugation, HaloTag for versatile applications, bioorthogonal chemistry (azide-alkyne click) for minimal footprint labeling, and genetic code expansion for true single-residue precision.

Can you label proteins that I already have expressed?

Yes, if your protein already contains a compatible tag (e.g., SNAP-tag, HaloTag, SpyTag), we can perform the labeling reaction using your existing material. For untagged proteins, we offer cloning services to add the tag at your desired position, followed by re-expression.

What quality control do you provide?

Every batch undergoes comprehensive quality control: SDS-PAGE analysis for purity assessment, mass spectrometry (ESI-MS or LC-MS/MS) to verify labeling efficiency and position, and endotoxin testing for mammalian cell-expressed proteins. You receive a detailed Certificate of Analysis with all QC data.

What is the minimum order quantity?

We offer flexible scales ranging from analytical (0.1 mg) for screening studies to gram-scale production for commercial applications. For most research applications, 1-10 mg is sufficient. Contact us with your specific requirements.

Do you support GMP-grade production?

Yes, we offer GMP-grade production for clinical and commercial applications. Our facilities comply with international quality standards, and we provide comprehensive documentation including batch records, certificate of analysis, and regulatory support.

How does genetic code expansion differ from other methods?

Genetic code expansion (GCE) enables incorporation of unnatural amino acids bearing bioorthogonal handles at the ribosome. Unlike protein tags (SNAP-tag, HaloTag), GCE adds only a single non-natural amino acid (~200 Da), resulting in minimal perturbation to protein structure and function. This is ideal for super-resolution microscopy and FRET studies.

Ready to Start Your Project?

Get a customized quote for your Site-Specific Protein Labeling Service project. Our experts will respond within 24 hours.

No obligation

24h response

Expert consultation

Request a Quote

Site-Specific Protein Labeling Services

Why Choose Us

Enzyme-Mediated Tags

Peptide Tag Systems

Bioorthogonal Chemistry

Precision Labeling for Consistent Results

1:1 Stoichiometric Ratio

Preserve Protein Function

Multiple Platforms

Mass Spec Verified

High Efficiency

Flexible Scale

Full QC Package

Ready to Eliminate Labeling Heterogeneity?

Advanced Labeling Technologies

Enzyme-Mediated Tags

Peptide Tag Systems

Bioorthogonal Chemistry

Genetic Code Expansion

Flexible Options for Diverse Needs

Streamlined Process from Design to Delivery

Consultation

Site Selection

Cloning

Expression

Labeling & QC

Delivery

Versatile Solutions Across Research Areas

Live Cell Imaging Applications

Therapeutic Development

Diagnostic Development

Structural Biology

What Our Clients Say

Scientific Foundation

Affinity-Directed Site-Specific Protein Labeling and Its Application to Antibody-Drug Conjugates

Site-Specific Proximity Labeling at Single Residue Resolution for Identification of Protein Partners

Segmental and Site-Specific Isotope Labelling Strategies for Structural Analysis of Posttranslationally Modified Proteins

Ultrafast Bioorthogonal Spin-Labeling and Distance Measurements in Mammalian Cells

Development of a New DHFR-Based Destabilizing Domain with Enhanced Basal Turnover and Applicability in Mammalian Systems

Frequently Asked Questions

Ready to Start Your Project?

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