丙酮萃取分光光度法测定水中叶绿素a实验条件的优化

基于丙酮萃取分光光度法,对叶绿素a测定方法进行深入研究,并通过单因素重复试验对冻存时间、冻存温度、萃取时间、萃取温度、细胞破碎方式、萃取剂浓度及萃取混合液提取方式等7方面的测定条件进行优化。优化后的实验条件为:水样经过抽滤后,置于-25℃低温冰箱中冻存12 h后取出,在常温下加入分析纯丙酮,用力振摇2 min至滤膜充分粉碎后定容到10 m L,静置不超过0.5 h,在离心机内以4 000 r/min的速度离心,取上清液进行比色。

Optimization of the Experimental Parameters in the Determination of Chlorophyll a in Water using Acetone Extraction Spectrophotometry

Based on acetone extraction spectrophotometry, the determination of chlorophyll-a was investigated in depth. Seven exper-imental parameters were optimized through single factor repeat experiments, including freezing time, extraction time and tempera-ture, cell lysis approaches, extractant concentrations and extraction approaches. The optimized experimental procedures were as fol-lows. Water samples were filtered and stored at -25℃ for 12 h. The samples were then allowed to restore to room temperature be-fore adding acetone and shaken vigorously for 2 min until the membrane was crushed completely. Samples were diluted to 10 mL and rested aside for less than 0. 5 h. Finally, the samples were centrifuged at 4 000 r/min and taken the supernatant for colorimetry.