Introduction

In biological detection techniques such as Western blotting, achieving highly sensitive detection of target molecules is essential. Although early methods widely relied on radioactive labeling due to their high sensitivity, they suffered from safety and stability issues, creating an urgent need for non-radioactive alternatives. Among the various detection methods, alkaline phosphatase (ALP)–based chemiluminescence has become dominant thanks to its high sensitivity, wide linear range, safety, and stability.

History of Alkaline Phosphatase Chemiluminescent Detection System

The first-generation alkaline phosphatase chemiluminescent substrates (such as AMPPD) laid the technological foundation for ALP-triggered chemiluminescence, but they exhibited insufficient signal-to-noise ratio in practical applications. This created strong market demand for a solution that maintains high sensitivity while providing lower background, stronger signals, and more stable output.

The second-generation substrates (such as CDP-Star) achieved a breakthrough through sophisticated chemical structural modifications. Their outstanding signal-to-noise ratio rapidly made them a preferred choice for high-end membrane detection. More importantly, CDP-Star strikes a critical balance among performance, cost, and technological maturity. Even after the emergence of third-generation substrates, it remains the top choice for laboratories seeking exceptional cost-effectiveness and reliable high performance.

The third-generation/new-generation substrates (such as APS-5) further optimize the molecular structure and enhancer systems based on the second generation, aiming to achieve an ideal balance among signal intensity, reaction speed, and background suppression.

CDP-Star: How does it achieve ultra-high sensitivity?

The chemiluminescent reaction of CDP-Star is specifically triggered by alkaline phosphatase:
First, ALP catalyzes the hydrolysis of the phosphate ester bond in the CDP-Star molecule, generating an unstable intermediate. Then, this intermediate undergoes spontaneous intramolecular electron rearrangement, causing the cleavage of the 1,2-dioxetane ring and producing an excited-state carboxylate ion. Finally, as the excited-state molecule returns to the ground state, it dissipates energy in the form of photon emission (maximum emission wavelength ~471 nm).

As a classic 1,2-dioxetane phosphate substrate, CDP-Star produces stable and intense luminescent signals upon ALP-catalyzed dephosphorylation. Compared with earlier substrates, the dephosphorylated product of CDP-Star has enhanced hydrophobicity and can form micelles with surfactants to enable signal amplification and background suppression, thereby delivering higher signal-to-noise ratios and faster detection speeds. This has made CDP-Star a flagship product in the field.

To further improve detection performance, Hzymes incorporates a specialized enhancer into the reaction system. By forming micelle structures with the luminescent intermediates, the enhancer amplifies signals and suppresses background, resulting in an exceptional signal-to-noise ratio. From CDP-Star molecular synthesis to enhancer optimization and luminescent formulation development, Hzymes has independently developed the entire process, producing a CDP-Star chemiluminescent solution with outstanding performance in signal-to-noise ratio, reaction speed, ease of use, and thermal stability—providing robust support for high-sensitivity detection.

Outstanding Performance of CDP-Star Chemiluminescent Solution

Long signal duration

CDP-Star chemiluminescent solution features rapid reaction kinetics, high signal intensity, and long-lasting signal stability.

High sensitivity and high signal-to-noise ratio

Comparative testing with different manufacturers’ chemiluminescent solutions was conducted using a fully automated chemiluminescent immunoassay analyzer with a PCT project.
① Background comparison shows that Hzymes’ CDP-Star solution has excellent background consistency.

② Calibration sample testing shows that Hzymes’ CDP-Star solution provides high sensitivity and a strong signal-to-noise ratio.

Inter-batch variation controlled within ±10%

Testing across multiple batches demonstrates inter-batch deviation maintained within ±10%.

Reduced injection volume while maintaining strong response

Adjusting the injection volume of the chemiluminescent solution still yields robust signal responses even with reduced volume.

37°C accelerated stability for 7 days with >90% signal retention

Comparative 37°C / 7-day thermal stability testing shows that Hzymes’ chemiluminescent solution retains over 90% of its luminescence value.

Product Information