包埋不同淡水耗氧菌BOD传感膜的光谱响应特征研究

利用四甲氧基硅烷（TMOS）、二甲基二甲氧基硅烷（DiMeDMOS）与聚乙烯醇（PVA）构成的有机改性材料分别包埋五种不同淡水耗氧菌，制备光化学生物耗氧量（BOD）的传感敏感膜，并在自行构建的BOD测定仪上考察其光谱响应行为。实验结果表明，分别包埋五种淡水耗氧菌和它们混合菌种的BOD传感膜对BOD的荧光强度响应范围为0～60 mg·L-1至0～120 mg·L-1，线性相关系数为0.976～0.997，响应时间为0.5～8.7 min，传感敏感膜可连续使用30 d以上。实验研究考察了不同实验条件下如温度和测定体系的pH对BOD传感膜响应的影响。实验结果发现，在4 ℃下保存12个月后，BOD传感膜仍保持原有响应值的85%以上，显示出较好的重复性和稳定性。初步应用结果表明，BOD传感膜可应用于地表水中的BOD检测。

Study on the Fluorescence Characteristics of BOD Sensing Films Immobilizing Different Limnetic Microorganism

Taking tetramethoxysilane (TMOS) and dimethyldimethoxysilane (DiMe-DMOS) as precursors for the synthesis of an organically-modified silicates (ORMOSILs)，optical BOD sensing films immobilizing five kinds of limnetic microorganisms were composed by poly(vinyl alcohol) ormosils matrix. Their fluorescence characteristics were studied with a home-made optical BOD apparatus. According to the experimental results, linearity between BOD and the corresponding fluorescence intensity ranging from 0-60 mg·L-1 to 0-120 mg·L-1 could be obtained on the sensing films immobilizing limnetic microorganisms and their mixture. In addition, the linearity coefficient was from 0.976 to 0.997, and the respond time was 0.5 to 8.7 min. In the experiment, effects of the measurement condition such as temperature and pH on the fluorescent responses of BOD sensing films were investigated. These sensing films presented excellent reproducibility and stability since they could be continuously employed for 30 days, and kept 85% of their original activity when stored for 12 months at 4 ℃. The approved approach could be applied in the BOD determination of real limnetic samples according to the obtained results.