苯基修饰二氧化硅纳米片纤维的制备及其对多环芳烃的固相微萃取

采用水热处理和溶胶-凝胶法在镍钛合金（NiTi）纤维表面组装了二氧化硅纳米片（SiO₂NFs），成功制备了新型SiO₂纤维涂层，并用苯基三氯硅烷进行了自组装表面修饰，得到了可用于固相微萃取（SPME）的NiO/TiO₂@SiO₂NFs-Ph纤维。将制备的SPME纤维与高效液相色谱联用，通过对典型芳香化合物的分析评价了所制备纤维的萃取性能。该纤维对多环芳烃（PAHs）具有较高的萃取率和良好的萃取选择性。实验优化了pH值、搅拌速率、萃取温度、萃取时间和离子强度对PAHs萃取率的影响。在优化条件下，5种PAHs在各自的范围内呈良好的线性关系，相关系数（r）大于0.999，检出限为0.013~0.108 μg/L。使用单根纤维对含有50 μg/L PAHs的加标水样进行萃取，其含量的日内及日间RSD分别为4.1%~5.9%和4.8%~6.8%。实际环境水样中5种PAHs在10 μg/L和30 μg/L加标水平下的加标回收率分别为90.8%~105.7%和93.6%~103.1%。该法制备的NiO/TiO₂@SiO₂NFs-Ph纤维稳定性高、制备重现性好，适用于环境水样中目标PAHs的富集和测定。

Preparation of phenyl-modified silica nanoflake fibers and the solid-phase microextraction of polycyclic aromatic hydrocarbons

A novel silica-based solid-phase microextraction (SPME) fiber was successfully fabricated by the immobilization of silica nanoflakes (SiO₂NFs) onto the hydrothermally treated nickel-titanium alloy (NiTi) wire using sol-gel method, followed by self-assembled surface modification of phenyltrichlorosilane. The extraction performance of the fabricated fiber was evaluated using typical aromatic compounds in direct-immersion mode of SPME. The fiber exhibited the high extraction capability and good extraction selectivity for polycyclic aromatic hydrocarbons (PAHs) in water samples. The influences of stirring rate, extraction temperature, extraction time and ionic strength on the extraction efficiencies were optimized coupled to HPLC with UV detection. Under the optimized conditions, the five PAHs presented good linearity in the certain mass concentration ranges with correlation coefficients (r) greater than 0.999, and LODs ranged from 0.013 to 0.108 μg/L. The intra-day and inter-day RSDs were from 4.1% to 5.9% and 4.8% to 6.8% for the PAHs at the spiked level of 50 μg/L with the single fiber, respectively. The recoveries of the five PAHs in real water samples spiked at 10 μg/L and 30 μg/L ranged from 90.8% to 105.7% and 93.6% to 103.1%, respectively. Moreover, the phenyl-modified SiO₂NFs coated NiTi fiber has high stability and good preparation reproducibility. The developed method is suitable for the concentration and determination of the target PAHs in environmental water samples.