Abstract：
Biochar, a sustainable sorbent derived from pyrolyzed biomass, has garnered attention for its efficacy in solid-phase extraction (SPE) of antibiotics, with a particular focus on tetracyclines (TCs). Despite its recognized potential, the intricate separation mechanisms operative in biochar-based SPE systems have not been fully deciphered. This investigation contrasts chlorella biochar against commercial bamboo biochar, harnessing an array of analytical methodologies-microstructure characterization, adsorption thermodynamics, competitive adsorption kinetics, H+ back titration, and selectivity adsorption studies-complemented by a Box-Behnken design for the optimization of chlorella/bamboo-SPE and subsequent application in the analysis of animal-derived foodstuffs. The study unveils that a hybrid sorbent, integrating nitrogen-doped microporous chlorella biochar with mesoporous bamboo biochar in a 95/5 mass ratio, markedly diminishes irreversible adsorption while enhancing selectivity, surpassing the performance of single biochar SPE systems. The elucidated separation mechanisms implicate a partition model, propelled by oxygen-rich functional groups on chlorella biochar and the rapid adsorption kinetics of bamboo biochar, all orchestrated by electrostatic interactions within the mixed biochar framework. Moreover, the synergy of mixed biochar-SPE with high-performance liquid chromatography (HPLC) demonstrates exceptional proficiency in detecting TCs in animal viscera, evidenced by recovery rates spanning 80.80 % to 106.98 % and RSDs ranging from 0.24 % to 14.69 %. In essence, this research not only sheds light on the multifaceted factors influencing SPE efficiency but also propels the use of biochar towards new horizons in environmental monitoring and food safety assurance.
摘要：
生物炭,一种来自热解生物质的可持续吸附剂，因其在抗生素固相萃取（SPE）中的功效而受到关注，特别关注四环素（TC）。尽管它具有公认的潜力，在基于生物炭的SPE系统中操作的复杂分离机制尚未完全破译。这项研究将小球藻生物炭与商业竹生物炭进行了对比，利用一系列分析方法-微观结构表征，吸附热力学，竞争吸附动力学，H+反滴定,和选择性吸附研究-辅以Box-Behnken设计，以优化小球藻/竹子-SPE，并随后将其应用于动物源性食品的分析。这项研究揭示了一种混合吸附剂，以95/5的质量比将氮掺杂的微孔小球藻生物炭与介孔竹生物炭集成，显著减少不可逆吸附，同时增强选择性，超越单一生物炭SPE系统的性能。阐明的分离机制暗示了一个分区模型，小球藻生物炭上的富氧官能团和竹子生物炭的快速吸附动力学,所有这些都是由混合生物炭框架内的静电相互作用协调的。此外，混合生物炭-SPE与高效液相色谱（HPLC）的协同作用证明了在动物内脏中检测TC的非凡熟练程度，回收率从80.80%到106.98%，RSD从0.24%到14.69%。实质上,这项研究不仅揭示了影响SPE效率的多方面因素，而且推动了生物炭在环境监测和食品安全保障方面的应用。
