Exploration of solid-state nanopores in characterizing reaction mixtures generated from a catalytic DNA assembly circuit

We adapt a solid-state nanopore for analyzing DNA assembly mixtures, which is usually a tougher task for either traditional characterization methods or nanopores themselves. A trigger induced nucleic acid amplifier, SP-CHA, is designed as a model. We propose an electrophoresis-gel like, but homogeneous, quantitative method that can comprehensively profile the “base-pair distribution” of SP-CHA concatemer mixtures.

Characterization of a liquid bridge microdroplet dispenser for use in molecular diagnosis

Microfluidic solutions offer the possibility of minimizing time-to-result, reagents and labour costs of molecular diagnosis, while improving their quality and accuracy. The use of droplets as microreactors represents one of the points of focus of this research. The current paper presents a geometry, referred to as a ‘two-way liquid bridge’, for dispensing microdroplets upstream of a nucleid acid amplifier. A single continuous phase, drawn through a capillary tube, can be automatically segmented into droplets of a predetermined size, with each droplet separated from its nearest neighbour and the wetted surface by an immiscible phase. The device has many advantages over previously reported segmenters. An experimental study, conducted in an adjustable device, demonstrates the effect of geometric parameters on the volume of fluid dispensed. Based on these experimental observations, a quasi-empirical theory is proposed to predict the dispensed volume for a given range of dispensed volumes, which is then demonstrated to work as a first-order design tool.