Synthetic Biology
Home / Services / By Technology / Protein Engineering Services / Protein Modification and Labeling Services
Trusted by Leading Research Institutions

Protein Modification & Labeling Services

Precision protein chemical modification and site-specific labeling solutions. From fluorescent tagging to therapeutic conjugates, we deliver homogeneous products with guaranteed batch consistency.

Site-Specific
99.5% Efficiency
ISO 9001
Learn More

Trusted by leading research and pharmaceutical institutions

Harvard
Pfizer
MIT
Roche
Stanford
Merck

Why Choose Us

Homogeneous site-specific conjugates
20+ modification chemistries
Complete analytical characterization
Function preserved after modification

Enzymatic Labeling

BirA, Sortase A, Transglutaminase

Chemical Bioconjugation

NHS ester, Maleimide, Click chemistry

ADC Development

cGMP manufacturing available

Market CAGR
12.4%
Overview Technology Specifications Workflow Applications FAQ
Service Overview

Precision Protein Modification Solutions

Our platform combines cutting-edge bioconjugation chemistry with rigorous quality control to deliver precisely modified proteins.

Site-Specific Precision

Achieve homogeneous labeling with our enzymatic and engineered modification platforms. Every molecule in your sample is modified at the same position with the same label.

  • Homogeneous products
  • Defined 1:1 stoichiometry
  • Consistent batch-to-batch

Function Preserved

Our mild reaction conditions and distal tag placement ensure your protein's native structure and biological activity remain intact after modification.

  • Mild reaction conditions
  • Activity retention verified
  • Distal modification sites

Complete Characterization

Every conjugate undergoes comprehensive analytical profiling including mass spectrometry and HPLC analysis.

Regulatory Support

Full documentation package including Certificate of Analysis for IND submissions and clinical applications.

Scalable Manufacturing

From milligram research scales to gram-scale GMP manufacturing without process changes.

Ready to Accelerate Your Research?

Get a customized quote for your protein modification project.

Technology Platform

Advanced Modification Technologies

Our integrated platform combines multiple modification strategies to achieve your specific labeling requirements.

Enzymatic Labeling

Leveraging the absolute specificity of biocatalysts to attach probes, tags, or functional groups to highly defined locations.

BirA Ligase Sortase A

Chemical Bioconjugation

Classic electrophilic chemistry for modifying nucleophilic amino acid residues with different selectivity profiles.

NHS Ester Maleimide

Self-Labeling Tags

Engineered protein tags that covalently bind to specific ligands, enabling rapid and complete labeling.

HaloTag SNAP-tag

Quality Control

MS LC-MS identity confirmation
HPLC Purity assessment
UV-Vis DOL determination
Activity Functional assay verification

Purification Methods

SEC Size exclusion chromatography
IEC Ion exchange chromatography
Affinity Tag-based purification
RP-HPLC Reversed-phase purification
Specifications

Service Specifications

Comprehensive modification options to meet diverse research and development needs.

Service Type Modification Options Typical DOL/DAR Scale Range
Fluorescent Labeling Alexa Fluor, FITC, Cy3/5, PE, APC 1-4 dyes per protein 0.1-10 mg
Biotinylation NHS-biotin, Maleimide-biotin, AviTag 1:1 stoichiometry 0.5-5 mg
Pegylation 2K, 5K, 10K, 20K PEG 1-8 PEG chains 1-100 mg
Site-Specific Labeling N-term, C-term, engineered sites Defined 1:1 ratio 0.5-50 mg
ADC Conjugation MMAE, MMAF, DM1, Payloads DAR 2, 4, or 8 10-1000+ mg
Crosslinking Homo/heterobifunctional, cleavable Variable 1-500 mg
Workflow

Streamlined Process from Design to Delivery

Our proven workflow ensures quality and efficiency at every stage.

1

Consultation

Project requirements review and strategy design

2

Method Development

Pilot reactions optimize conditions

3

Scale-up

Full-scale production with monitoring

4

Purification

Multi-step chromatography

5

Delivery

QC verification and documentation

Applications

Diverse Applications Across Biotechnology

Our modification services support research and development in multiple fields.

Live-Cell Imaging

Self-labeling tags enable real-time protein tracking in living cells without fixation artifacts. Rapid kinetics capture dynamic cellular processes.

  • Live-cell compatible labeling
  • Super-resolution microscopy support
  • Multiplex imaging capability
  • FRET studies
95%
Activity retention after labeling

Therapeutic Development

Homogeneous ADC development and therapeutic protein conjugation with controlled drug-to-antibody ratios and proven stability.

  • Antibody-drug conjugates
  • Therapeutic pegylation
  • Bispecific antibodies
  • cGMP manufacturing
20+
Payload options

Diagnostic Applications

High-signal conjugates with defined degree of labeling ensure bright, specific detection in panel design and multicolor diagnostics.

  • Flow cytometry
  • ELISA and immunoassays
  • Companion diagnostics
  • Lateral flow assays
1:1
Defined stoichiometry
Testimonials

What Our Clients Say

Trusted by researchers worldwide for quality and reliability.

"The site-specific labeling achieved homogeneity we could not get elsewhere. Our ADC development timeline accelerated significantly with their homogeneous DAR product."

R
Research Director
Pharmaceutical Company

"Batch-to-batch consistency is exceptional. We have scaled from research quantities to GMP manufacturing without any process changes. True partnership."

P
Principal Scientist
Biotechnology Company

"Their enzymatic labeling preserved enzyme activity that chemical methods destroyed. The comprehensive analytical data gave us confidence in our results."

L
Principal Investigator
Academic Research Institution
Scientific Literature

Scientific Foundation

Our platform is backed by peer-reviewed research.

78 Citations

Development and Recent Advances in Lysine and N-Terminal Bioconjugation for Peptides and Proteins

Tantipanjaporn A, Wong MK. Molecules. 2023.

Comprehensive review of lysine and N-terminal chemical modification methods including NHS esters, isothiocyanates, and site-selective strategies.

View DOI
45 Citations

C-terminal modification and functionalization of proteins via a self-cleavage tag triggered by a small molecule

Zeng Y, Shi W, Liu Z, Xu H, Liu L, Hang J, Wang Y, Lu M, Zhou W, Huang W, Tang F. Nature Communications. 2023.

Novel small molecule-triggered C-terminal modification method using self-cleaving tag technology achieving over 95% conversion efficiency.

View DOI
62 Citations

Photochemical protein modification in complex biological environments

Taylor MT. Biological Chemistry. 2022.

Review of photochemical protein modification technologies including affinity labeling, activity-based protein profiling, and photoaffinity labeling.

View DOI
38 Citations

Copper assisted sequence-specific chemical protein conjugation at a single backbone amide

Guo MZ, Zhao K, Guo L, Zhou R, He Q, Lu K, Li T, Liu D, Chen JF, Tang J, Fu X, Zhou JY, Zheng B, Mann SI, Zhang YD, Huang J, Yang B, Zhou T, Lei YJ, Dang BB. Nature Communications. 2023.

CAST method for site-specific protein backbone modification achieving rapid kinetics and homogeneous ADC preparation.

View DOI
22 Citations

Photoredox-Catalyzed Labeling of Hydroxyindoles with Chemoselectivity (PhotoCLIC)

Singha Roy SJ, Loynd C, Jewel D, Canarelli SE, Ficaretta ED, Pham QA, Weerapana E, Chatterjee A. Angewandte Chemie. 2023.

Visible light-catalyzed site-specific protein labeling using genetically encoded 5-hydroxytryptophan with over 95% conversion efficiency.

View DOI
FAQ

Frequently Asked Questions

Find answers to common questions about our service.

What is the difference between random and site-specific labeling?
Random labeling targets all reactive residues of a given type, resulting in a heterogeneous mixture with variable degree of labeling. Site-specific labeling modifies only one predetermined position, producing homogeneous conjugates with consistent properties.
How do you ensure batch-to-batch consistency?
We implement rigorous process controls at each step: optimized reaction conditions, real-time monitoring, and standardized purification protocols. Every batch undergoes identical analytical testing, and we maintain detailed batch records.
What quality control methods do you use?
Our standard QC package includes LC-MS for identity confirmation, HPLC/SEC for purity assessment, SDS-PAGE for aggregate analysis, UV-Vis for concentration and DOL determination, and functional assays where applicable.
Can you work with proprietary proteins?
Yes. We routinely handle customer-supplied proteins under strict confidentiality. We accommodate specific handling requirements and can often optimize conditions to maximize recovery and activity.
What is the typical degree of labeling (DOL)?
For random labeling, DOL typically ranges from 2-6 depending on protein and dye properties. For site-specific labeling, we achieve precise 1:1 stoichiometry with over 95% modification at the target site.
Do you offer cGMP manufacturing for clinical applications?
Yes. We have cGMP-compliant manufacturing capabilities for ADC development and therapeutic protein conjugation. Our facilities support scales from pilot to large-scale production with full regulatory documentation support for IND submissions.

Ready to Start Your Project?

Get a customized quote for your Protein Modification and Labeling Services project. Our experts will respond within 24 hours.

No obligation
24h response
Expert consultation

Recommended Services

· Protein PEGylation
· Site-Specific Protein Labeling Service
· Protein Structure Characterization Services
· Fluorescent Labeling of Proteins Service
· Protein Biotinylation Service

Related Resources

· Cost and Efficiency Analysis of CRlSPR-Cas9 Knockout Services in Mice and Cell Lines
· Validating CRISPR Knockouts: Best Practices for qPCR, Sequencing, and Functional Assays
· Step-by-Step Guide to Generating CRISPR Knockout Cell Lines for Research
Quick Links

Home

Products

Services

About Us

Contact Us

Follow Us
CONTACT US

USA

Tel:

Email:

Japan

Tel:

Email:

Korea

Tel:

Email:

Copyright © 2026 CD Biosynsis. All rights reserved.