藻类毒素是由有害藻类产生的次级代谢产物;这些代谢产物具有很强的毒性,多样化的结构和生物积累。以有害藻类为食的水生生物可以在体内积累藻类毒素,人类食用这些生物会导致瘫痪的症状,腹泻,甚至死亡。中毒的发作可以在短短30分钟内发生;在许多情况下,没有合适的解毒剂为藻类毒素是可用的。因此,藻类毒素对人类健康构成重大威胁,水产养殖业,和水生生态系统。因为藻类毒素的潜在风险是一个关键问题,这些毒素已成为研究热点。应对水环境和各类水产品进行监测和分析,以确保其安全。然而,由于可能的基质效应和实际样品中藻毒素含量低,在仪器分析之前,需要一种有效的预处理方法。高效的样品预处理技术不仅可以减少或消除分析过程中来自样品基质的干扰,而且可以富集目标分析物,以满足分析仪器的检测限,从而保证了检测方法的灵敏度和准确性。近年来,样品预处理技术,如固相萃取(SPE),固相微萃取(SPME),磁性SPE(MSPE),色散SPE(DSPE),基于移液管尖端的SPE(PT-SPE)在藻类毒素分离和分析领域得到了广泛的关注。这些预处理技术的性能在很大程度上取决于提取材料的特性。鉴于藻类毒素的不同物理化学性质,包括它们不同的分子大小,疏水性/亲水性,和指控,适用于藻类毒素提取的材料的设计和制备是一项必不可少的工作。最佳提取材料应当能够可逆地吸附藻类毒素,并且优选地具有大表面积的多孔结构,以允许高回收率和与毒素的良好界面接触。此外,提取材料应在工作pH范围内的样品溶液和洗脱溶剂中表现出良好的化学稳定性;否则,它可能会溶解或失去其官能团。许多研究努力试图开发具有这些特性的新型吸附材料,用于分离和分析藻类毒素。专注于碳基材料,金属有机框架(MOFs),共价有机骨架(COFs),分子印迹聚合物(MIP),以及它们的功能化对应物。碳基材料,MOFs,和COFs具有表面积大、吸附位点丰富等优点。这些提取材料广泛应用于复杂环境中目标物质的分离分析,生物,和食品样品由于其优异的性能和独特的微观结构。它们也是用于提取藻类毒素的主要吸附剂。这些提取材料在藻类毒素的提取中起着至关重要的作用,但它们也存在一些局限性:(1)碳基材料,MOFs,和COFs对目标物质的选择性吸附能力相对较差;(2)大多数MOFs在水溶液中不稳定,在从水基样品溶液中提取时难以应用;(3)COFs主要由轻质元素组成,使它们难以使用离心力从样品溶液中完全分离,这限制了它们的应用范围;(4)尽管MIP具有良好的选择性,模板分子丢失等问题,缓慢的传质速率,和低吸附能力必须解决。因此,设计和制备专门为藻类毒素定制的新型功能化提取材料,以及对新型复合提取材料的研究是非常理想的。本文收集了近十年来国内外藻类毒素分析研究的代表性文献,总结了相关发现,对新型功能材料在藻类毒素提取过程中的应用进行了分类,并对其未来发展前景进行了展望。
Algal toxins are secondary metabolites produced by harmful algae; these metabolites are characterized with strong toxicity, diverse structure and bioaccumulation. Aquatic organisms that feed on harmful algae can accumulate algal toxins in their bodies, and the consumption of these organisms by humans can cause symptoms of paralysis, diarrhea, and even death. The onset of poisoning can occur within as little as 30 min; in many cases, no suitable antidote for algal toxins is available. Thus, algal toxins present significant threats to human health, the aquaculture industry, and aquatic ecosystems. Because the potential risks of algal toxins are a critical issue, these toxins have become a research hotspot. The water environment and various types of aquatic products should be monitored and analyzed to ensure their safety. However, because of possible matrix effects and the low content of algal toxins in actual samples, an efficient pretreatment method is necessary prior to instrumental analyses. Efficient sample pretreatment techniques can not only reduce or eliminate interferences from the sample matrix during analysis but also enrich the target analytes to meet the detection limit of the analytical instrument, thereby ensuring the sensitivity and accuracy of the detection method. In recent years, sample pretreatment techniques such as solid-phase extraction (SPE), solid-phase microextraction (SPME), magnetic SPE (MSPE), dispersive SPE (DSPE), and pipette tip-based SPE (PT-SPE) have gained wide attention in the field of algal-toxin separation and analysis. The performance of these pretreatment techniques largely depends on the characteristics of the extraction materials. Given the diverse physicochemical properties of algal toxins, including their different molecular sizes, hydrophobicity/hydrophilicity, and charges, the design and preparation of materials suitable for algal-toxin extraction is an essential undertaking. The optimal extraction material should be capable of reversible algal-toxin adsorption and preferably possess a porous structure with a large surface area to allow for high recovery rates and good interfacial contact with the toxins. Additionally, the extraction material should exhibit good chemical stability in the sample solution and elution solvent within the working pH range; otherwise, it may dissolve or lose its functional groups. Many research efforts have sought to develop novel adsorbent materials with these properties in the separation and analysis of algal toxins, focusing on carbon-based materials, metal organic frameworks (MOFs), covalent organic frameworks (COFs), molecularly imprinted polymers (MIPs), and their functionalized counterparts. Carbon-based materials, MOFs, and COFs have advantages such as large surface areas and abundant adsorption sites. These extraction materials are widely used in the separation and analysis of target substances in complex environmental, biological, and food samples owing to their excellent performance and unique microstructure. They are also the main adsorbents used for the extraction of algal toxins. These extraction materials play an essential role in the extraction of algal toxins, but they also present a number of limitations: (1) Carbon-based materials, MOFs, and COFs have relatively poor selective-adsorption ability towards target substances; (2) Most MOFs are unstable in aqueous solutions and challenging to apply during extraction from water-based sample solutions; (3) COFs mainly consist of lightweight elements, rendering them difficult to completely separate from sample solutions using centrifugal force, which limits their application range; (4) Although MIPs have good selectivity, issues such as template-molecule loss, slow mass-transfer rates, and low adsorption capacity must be addressed. Therefore, the design and preparation of novel functionalized extraction materials specifically tailored for algal toxins and studies on new composite extraction materials are highly desirable. This article collects representative literature from domestic and international research on algal-toxin analysis over the past decade, summarizes the relevant findings, categorizes the applications of novel functional materials in algal-toxin-extraction processes, and provides an outlook on their future development prospects.