Characterization of a Protein Nanoparticle, Bsanano and its Interaction With-Emodin

Abstract

Despite the widespread use of high-throughput planar patch-clamp instruments, the conventional pipette-based technique remains the method of choice for recording single-channel activity. Generally, planar platforms are not well suited for single-channel studies due to excess noise resulting from low seal resistances and the use of substrates with poor dielectric properties. Since these platforms typically use the same pore to position a cell by suction and establish a seal, biological debris from the cell suspension can contaminate the pore surface prior to seal formation, thereby reducing the seal resistance. Here, femtosecond laser ablation is used to fabricate dual-pore glass chips for use in low-noise, single-channel recordings that circumvent this problem. One pore positions a cell by suction while another nearby pore, the recording pore, avoids contamination by maintaining positive pressure until a cell is positioned and then establishes a seal. Taking advantage of the high seal resistances and low capacitive and dielectric noise realized using glass substrates, patch-clamp experiments with these dual-pore chips consistently achieved high seal resistances (>10 GU), maintained gigaseals for prolonged durations (up to 6 hrs), and enabled single-channel recordings in cell-attached mode that are comparable to those obtained by conventional patch-clamp.