Phycobiliproteins [R-phycoerythrin (R-PE) and allophycocyanin (APC)] are commonly used ultrasensitive fluorescent dyes for biological assays. They are over 100 times more sensitive than traditional organic fluorophores. In practical applications in flow cytometry and immunoassays, the detection sensitivity of phycobiliprotein-conjugated antibodies is often far greater than that of corresponding organic fluorescent molecule conjugates (such as Alex Fluor and iFluor).
Despite their outstanding fluorescence performance, phycobiliproteins present one of the greatest challenges in antibody engineering.
With molecular weights of approximately 240 kDa for PE and 105 kDa for APC, these large protein fluorophores are traditionally attached to antibodies through chemical conjugation. While widely used, conventional conjugation methods suffer from several inherent limitations:
● Random labeling sites
● Uncontrolled dye-to-antibody ratios
● Batch-to-batch variability
● Loss of antibody activity during conjugation
● Difficult manufacturing standardization
● Reduced product consistency
Achieving site-specific, quantitative, and reproducible antibody-phycobiliprotein labeling has therefore remained an important yet unresolved goal in the antibody reagent industry.
Anti-Human IgG (Fcγ Fragment specific), AlpSdAbs® VHH (PE/APC)thus emerged. It is a product of the fusion expression and purification of high-affinity nanoantibodies that recognize Human IgG Fcγ Fragment with phycobiliprotein. It has high affinity and high specificity, making it very convenient for qualitative or quantitative analysis of antigen-antibody in flow cytometry experiments!
Anti-Human IgG (Fcγ Fragment specific), AlpSdAbs® VHH (PE/APC) does not bind to common mouse, rat, rabbit, or goat IgG!
a. Anti-Human IgG (Fcγ Fragment-specific), AlpSdAbs® VHH (PE/APC) binds well to all four subtypes of human IgG!
b. BLI affinity detection was performed using the BLI method to detect the binding of Anti-Human IgG (Fcγ Fragment specific), AlpSdAbs® VHH (PE/APC) to Human IgG1. with an affinity KD of 6.69E-10
c. Combined with Anti-Human IgG (Fcγ Fragment specific) with common mutations, AlpSdAbs® VHH (PE/APC) recognizes common mutations such as LALA, LALA+YTE, and dual antibody KIH structures
Anti-Human IgG (Fcγ Fragment specific) and AlpSdAbs® VHH (PE) flow cytometry assays were used to detect the binding ability of different antibodies to cells. The flow cytometric results showed high signal values and low background values.
Anti-Human IgG (Fcγ Fragment specific), AlpSdAbs® VHH (APC) flow cytometry was used to detect the binding ability of different antibodies to cells, with high flow cytometry signal values and low background values.
Code | Description | Applications | Size |
023-101-010 | Flow Cyt | 0.1mL | |
023-101-011 | Flow Cyt | 0.1mL |
As one of China's leading developers of recombinant nanobody reagents, AlpVHHs is committed to providing innovative tools for life science research and biopharmaceutical development.
Our expanding portfolio includes:
● Recombinant secondary antibodies
● Customized nanobody development services
By combining proprietary nanobody engineering with advanced recombinant expression technologies, AlpVHHs continues to deliver highly consistent, high-performance reagents that help researchers generate more reliable experimental results.
