传感器类型
表面等离子共振(SPR)生物传感器
检测对象
苯并咪唑氨基甲酸酯(BZT)残留:阿苯达唑(ABZ)、阿苯达唑亚砜(ABZ-SO)、阿苯达砜(ABZ-SO2)、芬苯达唑(FBZ)、芬苯达唑亚砜(FBZ-SO)、芬苯达砜(FBZ-SO2)、美苯达唑(MBZ)、羟美苯达唑(MBZ-OH)、氟苯达唑(FLU)、羟氟苯达唑(FLU-OH)、奥昔苯达唑(OXI);氨基苯并咪唑(amino-benzimidazole)残留:氨基-阿苯达唑砜(ABZ-NH2-SO2)、氨基-氟苯达唑(FLU-NH2)、氨基-美苯达唑(MBZ-NH2)、氨基-奥昔苯达唑(OXI-NH2)。样品基质:肝组织(liver tissue,DMSO提取液)
检测原理
该SPR生物传感器采用竞争免疫格式。CM5芯片表面经NHS/EDC活化和乙二胺胺化后,共价固定氨基-阿苯达唑羧基衍生物作为捕获抗原;样品提取液与绵羊多克隆抗体混合后流经芯片。肝组织中的BZT或氨基苯并咪唑残留与固定抗原竞争结合抗体,残留浓度越高,抗体与芯片结合越少,SPR共振单位(RU)变化越小。仪器在注射前后设定报告点记录结合信号,经四参数抑制曲线换算浓度。芯片用HCl/NaOH再生,实现无标记、实时、可重复检测。
检测灵敏度
BZT法:LOD: 32 μg kg−1;动态范围: 7 μg kg−1 (IC10)–340 μg kg−1 (IC90);IC50: 86 μg kg−1;CCα: 50 μg kg−1。氨基BZT法:LOD: 41 μg kg−1;动态范围: 22 μg kg−1 (IC10)–238 μg kg−1 (IC90);IC50: 44 μg kg−1;CCα: 75 μg kg−1。
效应效果
两种SPR法均按2002/657/EC验证。BZT法对11种残留的肝基质交叉反应(CR50)约91–110%,氨基法对4种氨基代谢物CR50约80–126%。加标回收率分别为77–132%和103–116%,批间CV为11–17%和8–16%。实际肝样与UHPLC–MS/MS比较,4个不合格样品均被SPR识别,无假合格,假不合格率约5%。方法可一天处理25个样品,适合快速筛查并减少确证分析量。
传感器的构成
- 基底/换能器:CM5 SPR芯片(GE Healthcare),提供SPR光学换能与表面官能团
- 表面活化层:NHS/EDC(N-羟基琥珀酰亚胺/碳二亚胺)活化羧基,形成活性酯
- 胺化层:1 M乙二胺(ethylenediamine)反应生成表面氨基,用于固定氨基苯并咪唑衍生物
- 固定识别层:氨基-阿苯达唑羧基衍生物(carboxy-amino-albendazole derivative)经EDC/NHS共价固定;BZT法固定层未在本文明细(引用前文)
- 封闭层:1 M乙醇胺(ethanolamine)封闭未反应位点,降低非特异结合
- 识别元件:绵羊多克隆抗体(anti-CMB-HSA或anti-amino-albendazole-BTG),与样品残留竞争结合固定抗原
- 读出层:Biacore Q SPR仪,以共振单位RU记录抗体结合变化
中文摘要
本研究开发并验证了两种表面等离子共振(SPR)生物传感器筛查方法,用于检测肝组织中11种苯并咪唑氨基甲酸酯(BZT)和4种氨基苯并咪唑兽药残留。方法采用绵羊来源多克隆抗体分别识别BZT和氨基苯并咪唑。针对BZT残留建立了改良QuEChERS前处理:乙腈提取,C18分散固相萃取净化;氨基苯并咪唑残留则用环己烷脱脂净化。按2002/657/EC标准验证。BZT法检出限32 μg/kg,检测能力CCα 50 μg/kg,平均回收率77–132%;氨基苯并咪唑法LOD 41 μg/kg,CCα 75 μg/kg,回收率103–116%。用UHPLC-MS/MS确证方法比较,所有不合格样品均被SPR生物传感器识别。
英文摘要
Two surface plasmon resonance (SPR) biosensor screening assays were developed and validated to detect 11 benzimidazole carbamate (BZT) and four amino-benzimidazole veterinary drug residues in liver tissue. The assays used polyclonal antibodies, raised in sheep, to detect BZTs and amino-benzimidazoles. A modified Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) extraction method was developed to isolate benzimidazole carbamate residues. Liver samples were extracted using an acetonitrile extraction method. BZTs were purified by dispersive solid phase extraction (d-SPE) using C(18) sorbent. Residues of amino-benzimidazoles were effectively cleaned-up using a simple cyclohexane defatting step. The assays were validated in accordance with the performance criteria described in 2002/657/EC. The BZT assay limit of detection was calculated to be 32 μg kg(-1), the detection capability (CCβ) was determined to be 50 μg kg(-1) and the mean recovery of analytes was in the range 77-132%. The amino-benzimidazole assay limit of detection was determined to be 41 μg kg(-1), the CCβ was determined to be 75 μg kg(-1) and analyte recovery was in the range 103-116%. Biosensor assay performance was tested by analysing liver tissue from animals treated with benzimidazole drugs and comparing the results with an ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) confirmatory method. All non-compliant samples were identified using the biosensor assays.