Streptavidin-clAPC Conjugate (SA-clAPC) | Flogen

Streptavidin-clAPC Conjugate (SA-clAPC) is a high-performance fluorescent detection reagent combining the exceptional biotin-binding capacity of streptavidin (Kd ≈ 10⁻¹⁵ M) with the enhanced stability of Flogen's proprietary cross-linked Allophycocyanin (clAPC).

Cross-linking stabilizes the native APC subunit structure, delivering superior photostability and stronger signal retention compared to standard APC conjugates — making it particularly valuable for detecting low-density targets and extended acquisition protocols.

SA-clAPC excites at 650 nm and emits at 660 nm, making it ideal for the far-red APC channel with minimal spectral overlap with FITC and PE. It is widely used in:

• Flow cytometry
• Bead-based multiplex assays (e.g., Luminex xMAP®)
• Microarray platforms (e.g., Affymetrix GeneChip®)
• Immunohistochemistry (IHC)
• Microplate-based immunoassays

Produced under strict QC control with ≥95% purity by SDS-PAGE. Available in 1 mg and 25 mg sizes, with custom specifications on request.

Product Specifications

Why Researchers Choose Flogen® SA-clAPC:

1. Proprietary clAPC raw material: Built on Flogen's in-house cross-linked APC, which is chemically stabilized to prevent subunit dissociation — delivering stronger, more reliable signals than standard APC conjugates.
2. Superior photostability: Cross-linking locks the APC trimeric structure in place, maintaining fluorescence intensity even under prolonged laser exposure or extended acquisition protocols.
3. High biotin-binding capacity: Streptavidin tetramers bind up to four biotin molecules with exceptionally high affinity (Kd ≈ 10⁻¹⁵ M), maximizing signal amplification from each binding event.
4. Far-red detection with minimal spectral overlap: Excitation at 650 nm and emission at 660 nm fits cleanly in the APC channel with negligible spillover into FITC and PE channels — ideal for multi-color panel design.
5. High purity: ≥95% by SDS-PAGE with SA:APC labeling ratio of 0.8–1.2, ensuring consistent lot-to-lot performance.
6. Low-density target detection: Enhanced signal retention makes SA-clAPC particularly effective when detecting rare or weakly expressed targets.
7. Custom specifications available: Available in 1 mg and 25 mg standard sizes, with bulk and custom conjugation options on request.

SA-clAPC is used in:

1. Flow cytometry (far-red APC channel; compatible with 633 nm and 640 nm red lasers)
2. Bead-based multiplex assays (e.g., Luminex xMAP®)
3. Microarray platforms (e.g., Affymetrix GeneChip®)
4. Immunohistochemistry (IHC)
5. Microplate-based fluorescent immunoassays
6. Detection of biotinylated antibodies, nucleic acids, and other biomolecules.