- Format: Single-Chain Variable Fragment (pelB Leader ⟶ VH 3-23 ⟶ (G4S)3 Linker ⟶ VK 1-39 ⟶ HA / 6xHis / Amber Cassette ⟶ cP3)
- Functional Diversity: 5.8×1010
- Phage Titer: ≥ 4.8 x 1012 pfu/mL
- The diversity and in-frame of the library were checked by NGS.
Product Description
The Fusion BioLabs Next-Generation Human Synthetic scFv Phage Display Library Kit (SKU: ADL-13) is an advanced antibody discovery platform designed for immediate therapeutic developability, clean freedom-to-operate (FTO), predictable industrial yields, and zero post-screen humanization bottlenecks.
Built upon the premier human germline pair VH 3-23 / VK 1-39, the library links the variable domains via a universal (G4S)3 peptide linker and incorporates a C-terminal HA tag, 6xHis tag, and Amber stop codon cassette prior to cP3. By utilizing targeted Trinucleotide Mutagenesis (TRIM) across the CDR loops while locking structural anchors solid, ADL-13 delivers high-affinity binding surfaces while maintaining exceptional thermal stability, an in-frame ratio of ≥ 95%, and high solubility.
Platform Architecture & CDR Design Summary
Fusion BioLabs ADL-13 Next-Generation Human Synthetic scFv CDRs Design Strategy
pelB Leader
→
VH Domain (VH3-23)
HCDR1
Soft Random.
Soft Random.
HCDR2
Soft Random.
Soft Random.
HCDR3
Trimer Mix
(12, 15, 18 AA)
Trimer Mix
(12, 15, 18 AA)
→
(G4S)3 Linker
→
VL Domain (VK1-39)
LCDR1
Soft Random.
Soft Random.
LCDR2
100% Fixed
100% Fixed
LCDR3
Trimer Mix
(Fixed 9 AA)
Trimer Mix
(Fixed 9 AA)
→
C-Terminal Cassette
HA • 6xHis • Amber Stop • cP3
HA • 6xHis • Amber Stop • cP3
| Region / Feature | Scaffold Baseline | Randomization Design | Functional Benefit |
|---|---|---|---|
| Frameworks | Human VH 3-23 / VK 1-39 | 100% Fixed Germline Anchors | High thermal stability and aggregation resistance |
| HCDR1 & HCDR2 | Germline IGHV 3-23 | Targeted Soft Randomization | Solvent-exposed diversity; structural anchors locked |
| HCDR3 | Synthetic TRIM Pools | Tri-Pool Lengths (12, 15, 18 AA) | Enriched binding pocket diversity without hydrophobic collapse |
| LCDR1 | Germline IGKV 1-39 | Targeted Soft Randomization | Balanced light-chain paratope engagement |
| LCDR2 | Germline IGKV 1-39 | 100% Fixed Baseline | Rigid structural bedrock preserving high expression yields |
| LCDR3 | Germline IGKV 1-39 | Fixed 9 AA Length | Optimal packaging geometry against heavy-chain domain |
| C-Terminal Tag | Synthetic Cassette | Fixed Functional Cassette | HA Tag + 6xHis Tag + Amber Stop Codon prior to cP3 |
Key Features & Design Highlights
- Massive Functional Diversity: Industry-leading diversity of 8 x 1010 unique transformants validated via Next-Generation Sequencing (NGS).
- Human Germline Master Scaffold (VH 3-23 / VK 1-39): Engineered on the stable human IGHV 3-23*01 and IGKV 1-39*01 (O12 allele) framework to maximize physical stability, resist aggregation, and ensure high microbial expression yields.
- Integrated HA / 6xHis / Amber Cassette: Standard C-terminal cassette enables streamlined nickel-affinity (IMAC) purification and direct soluble scFv expression in non-suppressor coli strains.
- Targeted CDR Diversification Strategy:
- HCDR1 & HCDR2: Soft-randomized at solvent-exposed contact positions while preserving internal loop anchors to maintain native loop geometry.
- HCDR3: Tri-pool length diversity strategy (12, 15, and 18 amino acids) biased toward functional antigen-binding residues to maximize pocket depth and contact diversity.
- LCDR1: Targeted soft randomization on exposed positions to ensure light-chain contribution during paratope engagement.
- LCDR2: 100% Fixed wild-type germline framework serving as a rigid structural bedrock to guarantee folding integrity.
- LCDR3: Fixed optimal 9-amino-acid loop length with controlled diversification to eliminate entropic binding penalties.
Target Application
- Therapeutic Discovery: Isolate high-affinity human single-chain binders requiring no humanization step prior to clinical development.
- CAR-T & Multispecific Engineering: Rapidly generate stable scFv candidates for immediate integration into chimeric antigen receptors (CARs) or bispecific antibody formats.
- High-Throughput Soluble Screening: Utilize the Amber stop codon to easily switch between phage display (in suppressor hosts) and soluble periplasmic expression (in non-suppressor hosts) for microtiter plate assays.
Kit Components
The following components are included in the kit.
Ready-to-panning Next-Generation Human Synthetic scFv Phage Display Library Kit Content
| Component | Quantity | Composition |
|---|---|---|
| Next-Generation Human Synthetic scFv library Phage (ready-to-panning phage; 4.8×1012pfu/ml) | 1.0 ml | 1×PBS with 25% glycerol |
| M13KO7 Helper Phage (2.0×1012 pfu/ml) | 0.5 ml | 1×PBS with 25% glycerol |
| Chemically Competent TG1 E. coli (2.5x108cfu/ml) | 0.5 ml | 2xYT with 25% Glycerol |
| M13 Rev Primer (1.6 μM) | 0.2 ml | 1×TE Buffer |
| pIII Rev Primer (1.6 μM) | 0.2 ml | 1×TE Buffer |
