Anti-interference Method And System Design In Situ Detection Of Cyanobacteria

Blooming has become one of the most important issues that threaten the global water environment,which brings great disaster to our production,life and ecosystems.In recent years,bloom often bursts in China's freshwater lakes which has destroyed the balance of water ecosystems.What's more,lots of algal toxins released by cyanobacteria are big threats to our health.So it is necessary to detect the planktonic algae which leads to the bloom in a timly,portable,fast and accurate way.There are many shortcomings in the current research method,such as complex process,time lag,high price and low efficiency.Besides,there are unavoidable fluorescence interferences among the pigments with fluorescence analysis,which results in the unaccuracy detection.Based on the the decoupling control and the Lambert's Law,we describe a method to improve the accuracy of phycocyanin in situ detection by anti-fluorescence interference decoupling algorithm,excluding the coupling interferences of the main pigments such as Chlorophyll a,Chlorophyll b and Phycocyanin.According to our research,we describe a method on selecting pigments' excitation and emission wavelengths to minimize the fluorescence interference among the main pigments.Then we combined this with multiple linear regression to build the detection modle between the fluorescence intensity and pigment concentration.So the detection of cyanobacteria biomass would be improved excluding the interference from others.Under our experimental conditions,we studied on the fluorescence spectral characteristics of Chlorophyll a,Chlorophyll b and Phycocyanin as well as the live algae including Microcystis aeruginosa and Chlorellavulgaris,and proved our method was effective.According to our results,The fluorescence interference can be minimized when Chlorophyll a was detected by excitation wavelength 442 nm and emission wavelength 682 nm,Chlorophyll b detected by excitation wavelength 464 nm and emission wavelength 662 nm,Phycocyanin detected by excitation wavelength 594 nm and emission wavelength 646 nm.And cyanobacteria biomass can be detected precisely.