Micro and Millifluidics Lab

Microfluidics System

KRG Microfluidics Lab (Wetlab) is equipped with Nikon ECLIPSE Ti2-E inverted microscope with Hamamatsu Orcaflash 4.0 16-bit CMOS Scientific camera. The system is fully motorized and can take upto 100 fps. The pump system allows both constant pressure and constant flow operation: the system includes two Cetoni neMESYS Low-Pressure module 290N syringe pumps (nanoliter - 0.1L per min), Elveflow MPS pressure sensors (low P model & high P model), and Fluigent Flow-EZ pressure pump & flow meters. PDMS microfluidic chips are fabricated at Minnesota Nano Center (MNC).

Millifluidics System

The KRG fluidics lab also uses millifluidic devices to capture fluid and chemical reaction phenomena in larger systems. In the current setup, polycarbonate plates are machined to form the desired flow channels and are manufactured in the UMN CSE machine shop. The plates are highly reusable, allowing for many experiments to be run from a single experimental system, and are currently used for mineral reaction experiments with cast plaster of paris. Flow is induced in these systems using a Harvard Apparatus 33 DDS syringe pump, capable of providing independent, twin, or reciprocating flows with low pulsation from flow rates of 1 picoliter/min to 0.1 liter/min with two syringes. The pump operates standalone, or can be controlled via computer, and can be used to sustain constant flow in one direction with a 1-way valve manifold. Experiments are performed on a ThorLabs vibration table, which reduces experimental disruptions due to ambient vibrations. Finally, the experiments can be imaged using an Alvium 1800u-511m scientific camera, a monochrome computer vision camera that provides 12-bit images and uses a 25 mm fixed focal length lens.

Micro PIV System

The KRG fluidics lab features a Dantec Dynamics micro Particle Image Velocimetry (uPIV) Stereoscope for characterizing flow fields in micro and millifluidic experiments. Featuring a 0.73x to 24x magnification range, the system is capable of resolving 3D 3 component velocities from micrometer/min to m/s velocities through the use of fluorescence beads. This is accomplished using a synchronized pulsed 532 nm laser and two cameras that utilize the stereoscopic effect to resolve vertical particle movement. The system is also capable of performing 2D Laser-Induced Fluorescence (LIF) imaging to capture trends in tracer transport or temperature variations, through the use of dyed fluids. The resulting images are processed and constructed into quantitative data through the use of the DynamicStudio software package.

Microbiology Instruments

Microbiology instruments at KRG include Labconco Logic-plus Class II A2 biosafety cabinet which meets BSL 1, 2, and 3 standards. Microbes are cultured in the VWR orbital shaking incubator and samples are stored in Lab Ref/Freezer combo units. Eberbach Waring Single Speed Blender is used to homogenize microbial solution and cell concentration is estimated using Shimadzu UV-1700 Spectrophotometer. An autoclave located on the first floor is used to sterilize samples and equipment. Cultured microbes are used in microfluidic experiments