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GenScript’s Comprehensive Protein Analysis Platform is an advanced, integrated system designed for in-depth study and evaluation of protein characteristics. It offers a wide range of services, including qualitative & quantitative analysis, protein modification analysis, impurity analysis, molecular interaction analysis, and more customized analysis. Together, these capabilities make the platform an essential tool in protein research, drug development, and biopharmaceutical production.
Qualitative & Quantitative Analysis
Protein Modification Analysis
Impurity
Analysis
Molecular Interaction
Analysis
Customized
Analysis
Waters BioAccord LC-MS
Thermo QE Orbitrap LC-MS/MS
Waters Xevo G3 QTOF
Biacore 8K
Octet RED
qPCR
Plate reader
TR-FRET
LabChip CE-SDS
Maurice iCIEF
Agilent GC
Cedex analyzer
Waters UPLC
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Qualitative & Quantitative Analysis
Molecular Interaction Analysis
Qualitative & Quantitative
Analysis
Protein Modification & Molecular
Interaction Analysis
Qualitative & Quantitative Analysis
Molecular Interaction
Protein Modification & Molecular Interaction Analysis
Discover their applications, benefits, and explore case studies below.
Qualitative & Quantitative Analysis | ||
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Applications | Assay list | Benefits |
Purity Analysis | SDS-PAGE |
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CE-SDS |
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HPLC |
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UPLC |
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Routine molecular weight detection |
Non-deglycosylated detection:
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N-glycan removal detection:
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Characterization of heavily glycosylated proteins |
Denatured N-glycan removal detection:
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Denatured N-glycan and O-glycan removal detection:
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Characterization of complex formation under the native state |
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Characterization of the complete protein sequence |
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Characterization of protein N-terminal and C-terminal sequences |
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Case1 Native mass - BsAb – Identification of the non-covalently linked chain
Native mass spectrometry is often used to identify the components of bispecific antibodies. The molecular weights of the marker bands in Fig 1A are 150 kDa, 120 kDa, 100 kDa, 74 kDa, and 23 kDa. Under denaturing conditions, the 150 kDa light chain was not identified by conventional mass spectrometry. This indicates that non-covalent interactions between proteins were disrupted under these conditions (Fig 1B). In contrast, native mass spectrometry reflected the original state of the proteins and successfully identified the light chain (Fig 1C).
Figure 1 SDS-PAGE and Mass analysis of BsAb1
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B
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Case 2 In-gel sequence coverage - Biotinylated protein – Identification for low concentration protein
Detection of biotinylation efficiency for protein-1 was requested by the customer. However, its concentration is far below the requirement and it is difficult to concentrate. Nevertheless, the SDS-PAGE bands were relatively clear (Fig 1). By excising the target band from the gel and performing coverage analysis, the biotinylation efficiency was successfully identified (Fig 2, Tab 1).
Figure 1 SDS-PAGE of protein-1
Figure 2 Fragment coverage map of protein-1
Table 1 Peptide coverage analysis of protein-1
Site | Mod | M/Z | Charge St. | Mono Mass Exp. | Mono Mass Theo. | △ ppm | Biotinylation ratio % |
K1296 | Biotinylation | 980.803 | 3 | 2938. 385 | 2938.392 | -2.36 | 99.3 |
Protein Modification Analysis | |
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Assay List | Benefits |
Glycosylation mirror comparison |
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Biotinylation ratio (peptide mapping) |
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Disulfide bond analysis |
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N-glycosylation site |
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PTM-phosphorylation |
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PTM-deamidaton | |
PTM-oxidation |
Case1 Glycosylation mirror comparison – Glycoprotein – Production process optimization and selection
Ab-1 and Ab-2 are the same protein produced by different hosts with different glycosylation patterns. Glycosylation mapping analysis identifies the glycosylation sites and proportions of Ab-1 and Ab-2, facilitating process optimization and selection.
Figure 1 Reduced Mass analysis of Ab-1 & Ab-2
Table 1 Glycosylation analysis of Ab-1 & Ab-2
NO. | Mass (Da) | Glycan Name | Ratio% | |
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Ab-1 | Ab-2 | |||
1 | 50063 | N Glycosylation Man5 | 3.3% | 1.4% |
2 | 50086 | N Glycosylation G0F-GlcNac | 5.9% | 4.2% |
3 | 50290 | N Glycosylation G0F | 84.5% | 85.9% |
4 | 50452 | N Glycosylation G1F | 6.3% | 8.6% |
Note:Mass value is from Ab-1.
Molecular Interaction Analysis | |||
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Applications | Assay List | Benifits | Recommendation |
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Bio-Layer Interferometry >> |
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Surface Plasmon Resonance >> |
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Case 1 SPR – IgG Affinity –SPR has high sensitivity and broad affinity detection range (KD = 10-3-10-15)
As shown in Fig 1 and Tab 1, SPR has higher sensitivity and a wider affinity detection range than BLI. SPR is suitable for both low-affinity (KD ~µM) and high-affinity (KD ~0.1 nM) samples, which may not be successfully detected by BLI.
Figure 1 Affinity binding curves of human IgG-1, 2, 3
Human IgG-1
Human IgG-2
Human IgG-3
Table 1 Affinity binding detailed analysis report of human IgG-1, 2, 3
Ab | Chip | Affinity | Test item | Chi² (RU²) | Ka (1/Ms) | kdis (1/s) | KD (M) |
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Human IgG-1 | ProA | Medium | Affinity | 4.90e-02 | 1.39e+05 | 2.07e-03 | 1.49e-08 |
Human IgG-2 | ProA | High | Affinity | 3.41e-01 | 2.75e+04 | 3.59e-05 | 1.30e-09 |
Human IgG-3 | ProA | Low | Kinetics | 4.75 | - | - | 3.818E-07 |
Case2 BLI v.s. SPR – IgG Affinity - BLI and SPR results are comparable for most antibody-antigen interactions
Most antigen-antibody interactions fall into the category of medium affinity samples, for which the detection results (KD) of BLI and SPR are nearly identical.
Rabbit IgG
Rabbit IgG
Mouse IgG
Impurity Analysis | ||
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Applications | Test Items | Benefits |
Host cell protein analysis | ELISA or LCMS |
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Residual DNA | qPCR based | / |
Residual Protein A | ELISA | / |
Case 1 Host cell protein analysis – Impurity protein – SDS-PAGE unknown band Identification
An unknown band was detected in several production batches of the protein (Fig 1). After excluding protein contamination, this band was suspected to be a host cell protein (HCP). HCP analysis preliminarily identified the band as phosphopyruvate hydratase (Tab 1). Further sequence analysis revealed a sequence coverage of 90.9% for this protein, confirming the band as the host cell protein phosphopyruvate hydratase (Fig 2).
Figure 1 SDS-PAGE of expression sample
Table 1 Sequence coverage map report of the unkown band
Figure 2 Sequence coverage map of the unkown band