Zeqi Zheng,Weitao Liu,Qixing Zhou,Jiantao Li,Aurang Zeb,Qi Wang,Yuhang Lian,Ruiying Shi,Jianlin Wang
Considering the stability and economy of immobilized enzymes, this study prepared co-modified biochar immobilized laccase product named Fe 3 O 4 @ [email protected] @LC via orthogonal experimental design and explored its possibility of remediating polycyclic aromatic hydrocarbons (PAHs) contaminated soil in steel plants. Compared with the free laccase treatment, the relative activity of Fe 3 O 4 @ [email protected] @LC remained 60 % after 50 days of incubation at room temperature. The relative activity of Fe 3 O 4 @ [email protected] @LC could still retain nearly 80 % after five reuses. In the process of simulating the PAHs-contaminated site treatment experiment in Hangzhou Iron and steel plant, immobilized laccase exhibited efficient adsorption and degradation performances and even the removal rate of 5-ring PAHs reached more than 90 % in 40 days, resulting in improving urease activity and dehydrogenase in the soil and promoted the growth of a PAH degrading bacteria ( Massilia ). Our results further explained the efficient degradation effects of Fe 3 O 4 @ [email protected] @LC on PAHs, which make it a promising candidate for PAHs-contaminated soil remediation.
Yi-Kun Li,Wei-tao Li,Xun Liu,Ting Yang,Ming-Li Chen,Jian-Hua Wang
A magnetic functionalized bio-sorbent based on aptamer was designed for the selective separation of ultra-trace Pb 2+ , shortly termed as Fe 3 O 4 @ [email protected] Pb(II) specific aptamer attached to the magnetic solid substrate served as affinity probe to capture and separate trace lead. Oligonucleotides with a polyA block were employed for the immobilization on the surface of AuNPs, with adenine sequences (polyA) as the part of effective anchoring block. The prepared Fe 3 O 4 @ [email protected] composites were characterized by FT-IR, SEM and XPS. The binding of lead on Fe 3 O 4 @ [email protected] composites surface was pH-dependent, the adsorption follows Langmuir model, and the adsorption dynamic fits the pseudo-second-order kinetics model. Procedure for lead separation and preconcentration was explored and combined with detection of graphite furnace atomic absorption spectrometry (GFAAS). Under the optimum condition, an enrichment factor of 17.73 was obtained with a sample volume of 1.0 mL. The limit of detection (LOD) was 57 ng L −1 along with a relative standard deviation (RSD) of 2.06 (n = 9). The procedure was further validated by a certified reference material GBW08608 and several environmental and blood samples.
危险品化学品经营许可证（带存储）