Luminol chemiluminescense reaction: a new method for monitoring nitric oxide in vivo Original Research Article

A new method employing a combination of microdialysis sampling and chemiluminescence (CL) detection was developed to monitor nitric oxide (NO) in vivo. A special probe was designed with an interference-free membrane to achieve very high selectivity for NO. High sensitivity was achieved by optimizing the working system and improving the NO sampling time. This system was used in vivo to monitor blood and brain tissue in rats and rabbits. The system is sensitive enough to detect variations of NO formation under different physiological states. The linear valid range of NO determination is 5 nM to 1 μM, with a 3σ detection limit of 1 nM; real NO concentrations in test animals used in this work were found to be in the range of 1–5 nM or even less. Finally, the effects of body temperature, NO donors, Viagra, NO activators, NO cofactors and NO interference (such as O2) were investigated carefully in different physiological situations.