When we first began developing a standardized protocol for μSiM-CA bacterial assays (described here), bad assay performance led some to believe our issues were due to availability of pores within the membranes inside of the μSiMs. At the same time,…
Category: NRG
Innocent Until Proven Guilty: Evaluating Pore Patency Across 0.5 μm Microporous Membranes for use in μSiM-CA Bacterial Assays
Posted in NRG
A Power-free Pneumatic System for Controlling Fluid Flow
Introduction When searching for a flow control system for microfluidic cell culture, we look to balance the ease of use, accessibility, and precision of fluidic control. For instance, researchers have explored different powered actuation methods for miniaturized precise proportional fluid…
Spot the Difference: Testing the Spatial Resolution of the Andor Dragonfly Confocal Microscope Using GFP Tagged Staphylococcus aureus and Nonporous Membranes
While imaging GFP tagged Staphylococcus aureus on our membranes within µSiM-CA devices, the question of whether or not we can differentiate between bacteria on the top and bottom of the membrane versus within the membrane has persisted. We know that during our…
Posted in NRG
Development of a TEER module for barrier tissue characterization
Introduction Tissue barriers separate different compartments of body organs. These barriers regulate the absorption of nutrients, maintain homeostasis, and prevent toxins from entering. In vitro models of tissue barriers have been developed to understand human diseases and investigate drug toxicity…
Staph Discipline: Pulling Staphylococcus aureus onto the Membrane to Encourage Timely Transmission
Since our attempt to standardize the Staphylococcus aureus µSiM-CA division assay, described here, we have moved towards investigating biological reasons as to why our assay performance is not where we want it to be. While biofilms have been suspect from the…
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Gene expression analysis of HUVECs cultured on uSiM (static vs flow)
Introduction Studies have shown that the shear-stimulation of endothelial cells results in the upregulation of the shear-sensitive transcription factor Kruppel-like factor 2 (KLF2). KLF2 plays a critical role in the regulation of endothelial activity such as the regulation of vascular…
Plasma Urea Clearance of Liftoff Device
Introduction This experiment is a continuation of previous work, cited below. Instead of urea spiked 1x PBS, whole heparinized bovine blood was pushed through the device over a period of four hours to then perform a urea assay on the…
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Urea Clearance of Liftoff Device
Introduction These results are thanks to assistance from Sam Walker and his previous posts regarding urea clearance that helped lay the foundation of this experiment. “Single Slot Inverted-Chip and Double Slot: Single-Pass Dialysis Devices” (Walker 2018) https://trace-bmps.org/single-slot-inverted-chip-and-double-slot-single-pass-dialysis-devices/ More information…
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Staphing Issues: Standardizing the Staphylococcus aureus µSiM-CA Division Assay
After continually seeing variability in assays using the microfluidic silicon membrane canalicular array (µSiM-CA) and developing a new technique to visualize bacterial division in the µSiM-CA, discussed here, we wanted to improve and stabilize the performance of our assays. Currently,…
Posted in NRG
A Move in the Light Direction: Visualizing Staphylococcus aureus Division Across Membranes Within µSiM-CA Devices Using Confocal Microscopy
Recently, several studies on Staphylococcus aureus (S. aureus) have been hindered due to poor performance from assays using the µSiM-Canalicular Array (CA). As discussed here, we attempted to improve assay performance by coating our membranes with fibronectin. This did not…
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