Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA) Universidad Nacional de La Plata - CONICET Sucursal, 4 Casilla de Correo 16, 1900 La Plata, Argentina; Escuela de Ciencias Básicas, Tecnología e Ingeniería, Universidad Nacional Abierta y a Distancia (UNAD), Bucaramanga, Santander, 680001 Colombia.
Soft Matter Nanotechnology Group, CIC biomaGUNE, Paseo Miramón 182 C, 20009 San Sebastián, Spain.
Bioelectrochemistry. 2021 Apr;138:107688. doi: 10.1016/j.bioelechem.2020.107688. Epub 2020 Nov 10.
Supported Lipid Bilayers (SLBs) on Polyelectrolyte Multilayers (PEMs) have large potential as models for developing sensor devices. SLBs can be designed with receptors and channels, which benefit from the biological environment of the lipid layers, to create a sensing interface for ions and biomarkers. PEMs assembled by the Layer-by-Layer (LBL) technique and used as supports for a lipid bilayer enable an easy integration of the bilayer on almost any surface and device. For electrochemical sensors, LBL assembly enables nanoscale tunable separation of the lipid bilayer from the electrode surface, avoiding undesired effects of the electrode surface on the lipid bilayers. We study the fabrication of valinomycin-doped SLBs on PEMs as a model system for biophysical studies and for selective ion sensing. SLBs are fabricated from dioleoylphosphatidylcholine (DOPC) and dioleoylphosphatidylserine (DOPS) 50:50 vesicles doped with valinomycin, as a K-selective carrier. SLBs were deposited on electrodes coated with poly(allyl amine hydrochloride) (PAH) and poly(styrene sodium sulfonate) (PSS) multilayers. Lipid bilayer formation was monitored by using Quartz Crystal Microbalance with Dissipation (QCMD) technique and Atomic Force Microscopy (AFM). Electrochemical impedance spectroscopy (EIS) and potentiometric measurements were performed to assess K selectivity over other ions and the potential of valinomycin-doped SLBs for K-sensing.
基于聚电解质多层膜（PEMs）的支撑脂质双层（SLBs）在开发传感器设备方面具有很大的潜力。SLBs 可以设计带有受体和通道，这得益于脂质层的生物环境，从而为离子和生物标志物创建一个传感界面。通过层层（LBL）技术组装的 PEM 用作脂质双层的支撑，可使双层很容易集成到几乎任何表面和设备上。对于电化学传感器，LBL 组装可实现纳米级可调脂质双层与电极表面的分离，避免电极表面对脂质双层产生不必要的影响。我们研究了在 PEM 上制备缬氨霉素掺杂的 SLBs，作为生物物理研究和选择性离子传感的模型系统。SLBs 由二油酰基磷脂酰胆碱（DOPC）和二油酰基磷脂酰丝氨酸（DOPS）50:50 囊泡组成，其中掺杂了缬氨霉素作为 K 选择性载体。将 SLBs 沉积在涂有聚烯丙基胺盐酸盐（PAH）和聚苯乙烯磺酸钠（PSS）多层膜的电极上。通过使用石英晶体微天平耗散（QCMD）技术和原子力显微镜（AFM）监测脂质双层的形成。进行电化学阻抗谱（EIS）和电位测量，以评估对其他离子的 K 选择性以及缬氨霉素掺杂的 SLBs 用于 K 传感的潜力。
