组成图示
示意图生成中
传感器类型
荧光生物传感器
检测对象
三乙胺(triethylamine, TEA);样品基质:去离子水/囊泡分散液
检测原理
该传感器以 PCDA 脂质囊泡为骨架,掺入 BODIPY 染料(BO558)后经紫外光聚合形成共轭 PDA 囊泡。聚合后 PDA 共轭骨架与 BODIPY 之间发生有效能量转移/电子相互作用,使 BODIPY 荧光被强烈猝灭,形成低背景状态。当加入三乙胺(TEA)等弱碱时,TEA 提高溶液 pH,使囊泡膜头基去质子化并产生负电荷排斥,导致囊泡膨胀、侧链间距增大,PDA 共轭骨架构象与染料间距发生变化,从而减弱染料向 PDA 的能量转移,BODIPY 荧光恢复。荧光增强幅度随 TEA 浓度增加而增大,在 50 μM–2 mM 范围内呈线性,实现直接正向荧光检测。
检测灵敏度
LOD: 10 μM;线性范围: 50 μM–2 mM
效应效果
系统对 TEA 呈线性响应,检测限为 10 μM,线性范围为 50 μM–2 mM。碱处理诱导的荧光恢复可逆,重复加碱后的恢复强度与首次相当,显示良好重现性。DLS 显示囊泡粒径在紫外聚合前后由 113±2 nm 变为 109±2 nm,NaOH 处理后膨胀至 253±5 nm。掺入 PC 会降低猝灭效率,从 97% 降至 72%(50% PC),并使 200 μM TEA 的净荧光恢复从 7650 降至 100;30% PC 仍保留 2100 的恢复信号,说明体系可容纳生物识别单元。作者认为该信号转导快速、可逆且灵敏,适合作为化学/生物传感器平台,但未报告选择性、抗干扰、实际样品回收率或与 ELISA/HPLC/qPCR 的对比。
传感器的构成
- 囊泡骨架/换能材料:10,12-戊二炔酸(PCDA)脂质经紫外光聚合形成共轭聚二炔(PDA)囊泡,提供共轭骨架并介导荧光猝灭/恢复。
- 荧光信号标记:BODIPY 558/568 C12(BO558)脂溶性荧光染料,以 0.25 mol% 掺入囊泡双分子层,作为荧光报告基团。
- 膜组分调节层:磷脂酰胆碱(PC)脂质,可按 10–50 mol% 掺入,稀释二炔共轭链、降低猝灭效率并模拟生物膜。
- 对照脂质层:卵磷脂酰甘油(Egg PG)脂质,用于无二炔对照,证明荧光猝灭与 PDA 共轭结构相关。
- 识别/响应元件:囊泡膜头基与溶液 pH/有机胺相互作用,TEA 作为弱碱提高 pH 并触发荧光恢复;未使用抗体/适配体等特异性生物识别元件。
- 读出介质:去离子水、玻璃比色皿或 96 孔板,承载囊泡分散液并用于荧光光谱测量。
中文摘要
本文报道了一种基于纳米脂质膜的共轭聚二炔(PDA)囊泡传感器,用于有机胺的荧光检测。该囊泡传感器通过将 BODIPY 荧光染料掺入 PDA 囊泡中构建而成,所得囊泡的荧光性质可通过调节脂质组分进行操控,并受环境与溶液条件控制。在二炔脂质囊泡经紫外光聚合形成 PDA 的过程中,BODIPY 荧光被显著猝灭;然而,当溶液 pH 升高等外部刺激作用时,荧光可充分恢复。该荧光恢复过程具有可逆性,降低溶液 pH 可再次引起猝灭。所报道系统能将外部刺激转化为显著的荧光强度变化,展示了在生物传感器设计中开发新型信号报告方法的潜力。BODIPY–PDA 体系的猝灭–恢复现象被认为与染料和 PDA 共轭骨架之间的能量转移有关。作者将该囊泡传感器用于检测有机胺三乙胺(TEA),荧光强度增加与 TEA 浓度之间获得良好线性关系,基于荧光恢复的 TEA 检测限为 10 μM。
英文摘要
We report a nanoscale lipid membrane-based sensor of conjugated polydiacetylene (PDA) vesicles for fluorescence detection of organic amines. The vesicle sensor was constructed by incorporation of a BODIPY fluorescent dye into the PDA vesicles. The fluorescent properties of the resulting vesicles can be manipulated by adjusting lipid components, and are controlled by environmental and solution conditions. The fluorescence of the BODIPY dye was significantly quenched in the polymerization of diacetylene lipid vesicles by a UV irradiation process. However, it was sufficiently recovered by external stimuli such as a hike of solution pH. The fluorescence recovery process was reversible, and a decrease in solution pH resulted in repeated quenching. The reported system transforms an external stimulus into a large fluorescence intensity change, demonstrating great potential in developing new signal reporting method for biosensor design. The quench-recovery phenomenon of the BODIPY-PDA is believed to be related to the energy transfer between the dye and the PDA conjugate backbone. The vesicle sensor was applied for detecting an organic amine, triethylamine (TEA) and a large linear relationship was obtained between the increase in fluorescence intensity and the concentrations of TEA. The detection limit of TEA by vesicle sensors using fluorescence recovery was found to be 10muM.