Applications
Many applications and instruments were developed specifically for allophycocyanin. It is commonly used in immunoassays such as flow cytometry and high-throughput screening. It is also a common acceptor dye for FRET assays.
Structural Characteristics
Allophycocyanin can be isolated from various species of red or blue-green algae, each producing slightly different forms of the molecule. It is composed of two different subunits (α and β) in which each subunit has one phycocyanobilin (PCB) chromophore. The subunit structure for APC has been determined as (αβ)3. The molecular weight of APC is 105,000 Daltons.
| Absorption maximum | 652 nm |
| Additional Absorption peak | 625 nm |
| Emission maximum | 657.5 nm |
| Stokes Shift | 5.5 nm |
| Extinction Coefficient | 2.4 x 105 M-1cm-1 |
| Quantum Yield | 0.68 |
| Brightness | 1.6 x 105 M-1cm-1 |
Specifications
| A650/A280 ≥ 4.0 |
| A650/A620 ≥ 1.25 |