A Coaxial Jet Mixer for Rapid Kinetic Analysis in Flow Injection and Flow Injection Cytometry

Abstract

A simple coaxial jet mixer for rapid and efficient confluent mixing under laminar flow conditions (Re < 5) is described. This device demonstrates exceptional control of mixing between two laminar streams by creating shear forces due to variable flow velocities at the point of confluence. It is suitable for flow injection and cytometric analyses of rapid kinetic events which require contact mixing of two solutions and subsecond measurements of the evolving reaction. This apparatus was devised for flow injection cytometry as performed on a Becton Dickinson FACS Analyzer. Under normal cytometric conditions and at a sample introduction rate of 60 microL/min, the laminar jet mixer is capable of complete mixing of two solutions within 55 ms. Kinetic measurements can be performed on the FACS Analyzer in a variable time range of 100 ms to 3 min with 14-30 ms temporal resolution of the studied event. Since no boost in core flow is required, potential spectral distortions due to core flow variations are eliminated. This coaxial jet mixer can be easily constructed and employed on a variety of cytometers as well as conventional flow injection analysis systems, since it is an effective mixer under most flow conditions.

Investigation of Nonlinear Electrokinetic and Rheological Behaviors of Typical Non-Newtonian Biofluids through Annular Microchannels

“…Microannulus is a widely applicable form of microchannels used in the design and fabrication process of many practical micro technologies such as micro-heat pipes, -heat exchangers, -mixers, and micro-reactors (Nouri-Borujerdi and Layeghi 2005;Westheimer and "Bud" Peterson 2001;Scampavia et al 1995;Kuznetsov et al 2009). In practice, EOF in a capillary annulus is encountered in applications such as electrophoretic separation of proteins and chemical remediation of contaminated soil.…”

Transient electro-osmotic flow in cylindrical microcapillaries containing salt-free medium

“…[12][13][14] Further, the cylindrical capillary has been widely used in biological chips such as micropumps, 15 capillary electrophoretic devices for separation of proteins, 16 and coaxial jet mixing devices used in chemical analysis and biomedical diagnostics. 17,18 Therefore, it is necessary to study the transient response of EOF in a cylindrical microcapillary containing a salt-free medium.…”

Nozzle design parameters and their effects on rapid sample delivery in flow cytometry

“…Because the time scale for many cellular events occurs in seconds or even milliseconds, which is too fast for traditional flow cytometric instrumentation, special-purpose flow cytometers have been developed. There are two rapid approaches for analyzing mixed reactions on a flow cytometer, time window methods (2)(3)(4)(5) and continuous analysis methods (6 -13).…”

“…This method is exemplified by coaxial mixing flow cytometers, which use a special purpose mixer that allows for the sample to be mixed rapidly with minimal disturbance of the sample or sheath flow. The mixing device is small, so it can be positioned close to the point of analysis allowing for observation of the reaction within 100 ms (4). By changing the position of the mixer relative to the analysis point, reactions have been monitored from 100 ms to 3 s (5).…”