球形棕囊藻的荧光光谱特征及定量测定

The Characteristics of Fluorescence Emission Spectra in Vivo of Phaeocystis globosa and Quantitative Analysis

研究了球形棕囊藻的活体荧光光谱,发现在红光区681 nm荧光峰为主峰,735 nm有一肩峰。在681nm和735 nm两处分别测定了激发光谱,两光谱形状相同,只是强度有较大差别。在同步发射光谱中,球形棕囊藻的荧光峰处于684 nm,发生了红移。通过与经0.2μm微孔滤膜过滤的藻液光谱图相比较,发现550 nm处散射峰强度与藻细胞微粒数量成正相关。文中藻密度范围从104cell/mL到106cell/mL,在λex=467 nm,λem=681 nm和λex=λem=550 nm两测定条件下,发现藻密度与荧光强度、散射峰强度均呈较好的线性关系。因此,用球形棕囊藻产生的叶绿素荧光和共振瑞利散射对球形棕囊藻进行定量的两种方法是可行的。

The characteristics of fluorescence spectra of Phaeocystis globosa were studied, it was found that the fluorescence emission spectra of Phaeocystis globosa excited by λ467nm λ533nm and λ588nm, respectively, exhibited two distinct peaks in the infrared region： the principal peak at λ681nm and the shoulder peak at λ735nm. Both were emitted by chlorophyll a. The excitation spectra measured at λ681nm and λ735nm, respectively, all exhibited three peaks at λ467nm,λ533nm and λ588nm, but their intensities were quite different. The peak in the synchronous emission spectra of Phaeocystis globosa was red shifted to λ684 nm compared with the fluorescence emission peak of Phaeocystis globosa at λ681nm. In the synchronous emission spectra, the intensity of the scattering peak at λ550nm was correlated well with the number of algae cell. Under the conditions： λex =467 nm, λem =681 nm for fluorescence, and λex =λem = 550 nm for resonance Rayleigh scattering （RRS）, the fluorescence intensity and the RRS intensity were linearly proportional to the Phaeocystis globosa cell density, respectively. The cell density was in the range of 10^4 cell/mL to 10^6 cell/mL.