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The prompt introduction of single-molecule science into undergraduates' curricula is an urgent but challenging task. However, the research experiments are often too complicated and the instruments are too expensive to be widely transferred into a compulsory course of undergraduate students. Herein, we introduce a recently developed nanopore technique into an accessible laboratory course for students with the advantages of simple operation, high repeatability, and low cost. The nanopore course serves to help undergraduates in practice to understand single-molecule behaviors, think at a single molecule level, and gradually develop single-molecule solutions for scientific issues. The learning activities for undergraduate students include setup of the instrument, fabrication of a biological nanopore on an artificial lipid bilayer membrane, detection of individual oligonucleotides, and data analysis. An experiment example is single-molecule detection of the model DNA sample poly(dA)[subscript n] (n = 4, 5) using the aerolysin nanopore. As our developed nanopore sensing system is simple, portable, and easy to handle, the experiment course could be implemented and popularized in undergraduates' laboratory education. For the undergraduate students who have taken general chemistry and/or biochemistry courses, this hands-on experience of nanopore experiments would benefit them with a better understanding of the chemical world at a single-molecule level and further using single-molecule tools in various applications including DNA and/or protein sequencing.

The microtubule‐associated protein tau participates in neurotransmission regulation via its interaction with synaptic vesicles (SVs). The precise nature and mechanics of tau's engagement with SVs, especially regarding alterations in vesicle dynamics, remain a matter of discussion. We report an electrochemical method using a synapse‐mimicking nanopipette to monitor vesicle dynamics induced by tau. A model vesicle of ~30 nm is confined within a lipid‐modified nanopipette orifice with a comparable diameter to mimic the synaptic lipid environment. Both tau and phosphorylated tau (p‐tau) present two‐state dynamic behavior in this biomimetic system, showing typical ionic current oscillation, induced by lipid‐tau interaction. The results indicate that p‐tau has a stronger affinity to the lipid vesicles in the confined environment, blocking the vesicle movement to a higher degree. Taken together, this method bridges a gap for sensing synaptic vesicle dynamics in a confined lipid environment, mimicking vesicle movement near the synaptic membrane. These findings contribute to understanding how different types of tau protein regulate synaptic vesicle motility and to underlying its functional and pathological behaviours in disease. [ABSTRACT FROM AUTHOR]

Cell migration is known to be a fundamental biological process, playing an essential role in development, homeostasis, and diseases. This paper introduces a cell tracking algorithm named HFM-Tracker (Hybrid Feature Matching Tracker) that automatically identifies cell migration behaviours in consecutive images. It combines Contour Attention (CA) and Adaptive Confusion Matrix (ACM) modules to accurately capture cell contours in each image and track the dynamic behaviors of migrating cells in the field of view. Cells are firstly located and identified via the CA module-based cell detection network, and then associated and tracked via a cell tracking algorithm employing a hybrid feature-matching strategy. This proposed HFM-Tracker exhibits superiorities in cell detection and tracking, achieving 75% in MOTA (Multiple Object Tracking Accuracy) and 65% in IDF1 (ID F1 score). It provides quantitative analysis of the cell morphology and migration features, which could further help in understanding the complicated and diverse cell migration processes. [ABSTRACT FROM AUTHOR]