flowrate sensors  (Sensirion ag)

Journal: bioRxiv

Article Title: A workcell 1.0 for programmable and controlled operation of multiple fluidic chips in parallel

doi: 10.1101/2023.04.16.536594

Figure Lengend Snippet: Figure 2: (A-D) Schematic depicting the Load, Advance, Introduce, and Reset stages of the flow protocol that is used to move reagents from their tubes to an array of chips an arbitrary distance away, with low dead-volume. (E) Layout showing the different layers of the cooling block, which the tubes sit in while they are docked to the pressure-head. (F) Characterization of the cooling system. Temperature readings are generated by a high-precision resistance temperature detector (RTD, Pt-100) which sits in water inside of a dummy laboratory tube. (G) Chips that were used on the workcell in this study. Chip from , C, E (top), chip from (middle), chip from (bottom). (H) Demo protocol for controlling the workcell to operate chips (functional syntax is similar in simplicity). Hierarchical function definitions are shown below for “flow”, which calls “Load”, “Advance”, “Introduce”, and “Reset” functions. Functions are imported at the beginning of a protocol file. (I) Schematic overview of software architecture. The automancer software communicates by OPCUA to software and hardware running on the PLC. (J-K) Depictions of programs running on the PLC. (J) Depiction of inlet-valve pulse-width modulation (PWM) used to automate reagent mixing and on-chip dilutions. Automancer communicates to turn on PWM-mode for a specific channel, and supplies a period, and duty-cycle to the PLC, to select a specific dilution level or mixing ratio. Schematic waveforms are shown for a 40% duty cycle used to dilute orange reagent (top). An example pulse from the PLC is shown as characterized using a logic analyzer (top right). More extensive PWM characterization is shown in Supplementary Figure 3. (K) Characterization of the flowrate controller. Automancer directs the PLC to operate in flowrate-control mode, and supplies a flowrate setpoint. A characterization across a wide range of flowrates is shown in Supplementary Figure 2, and stability across resistance perturbations in .

Article Snippet: In our flow-controller we use Sensirion flowrate sensors, Emerson ED02 pressure controllers, and we implement proportional integral derivative (PID) control through a Siemens Simatic S-1500 series programmable logic controller (PLC), to enable rapid and high-resolution flowrate control ( ).

Techniques: Introduce, Blocking Assay, Generated, Functional Assay, Software

Journal: Children

Article Title: Partial Obstruction of Ventricular Catheters Affects Performance in a New Catheter Obstruction Model of Hydrocephalus

doi: 10.3390/children9101453

Figure Lengend Snippet: Experimental setup of the catheter performance system. A syringe pump (Fusion 200-X, Chemyx, Inc., Stafford, TX, USA) injecting artificial CSF at 1 mL/min was used as the fluid source. ( A ) Commercial pressure transducer (PX409-100 GUSBH, Omega, Inc., Biel/Bienne, Switzerland) and flow rate sensor (SLF3S-0600F, Sensirion, Inc., Stäfa, Switzerland) were used for measurement of internal pressure of the phantom and CSF flow rate through the catheter, respectively. ( B ) Experimental setup for pressure measurement in the catheter. ( C ) The 3D-printed ventricular phantom; actual printed part ( left ). The phantom was designed by Fusion 360 software and fabricated by SLA (Stereolithography) 3D printer (Form 3B, Formlabs) using elastic resin (Elastic 50A, Formlabs). Cross-sectional schematic of the phantom with the inserted catheter (middle). Catheters obstructed by epoxy resin by 20%, 40%, 60%, 80%, and 95% (from left to right ). ( D ) A catheter was inserted into the silicon tubing instead of the phantom.

Article Snippet: The bench-top setup consisted of the ventricular catheter (barium striped silicone catheter, Medtronic, Inc., Dublin, Ireland), 3D printed ventricle phantom, syringe pump (Fusion 200-X, Chemyx, Inc., Stafford, TX, USA), a pressure transducer (PX409-100 GUSBH, Omega, Inc., Biel/Bienne, Switzerland), and flowrate sensor (SLF3S-0600F, Sensirion, Inc., Stäfa, Switzerland).

Techniques: Software

Journal: bioRxiv

Article Title: Pressure-driven perfusion system to control, multiplex and recirculate cell culture medium for Organs-on-Chips

doi: 10.1101/2022.07.21.500785

Figure Lengend Snippet: (a) Used fluidic circuit (b) Applying a fixed Pressure difference results in a constant decrease of the flowrate per displaced volume due to effect of P head .(b) Fixed flowrate shows a steady increase in applied pressure due to the changing P head using fixed flowrate.

Article Snippet: A Flowrate sensor (Fluigent, XL) was thoroughly cleaned by rinsing with 70% ethanol, followed by incubation with hypochlorite (Glorix) for 20 min. After incubation the sensor was subsequently rinsed with 10 ml ddH 2 0, 10 ml propanol and dried with nitrogen.

Techniques:

Journal: bioRxiv

Article Title: Pressure-driven perfusion system to control, multiplex and recirculate cell culture medium for Organs-on-Chips

doi: 10.1101/2022.07.21.500785

Figure Lengend Snippet: (a) Schematic of the fluidic circuit used to validate sensor accuracy. A 10 ml serologic pipette was attached to the outlet of the circuit and the pressure controller was set to a fixed flowrate using the internal PID-loop. At multiple intervals, time was noted and the flowrate was calculated (b) A clean sensor accurately measures the flowrate of cell culture medium (orange plot); after two days of continuous perfusion, the sensor becomes inaccurate(blue plot)

Article Snippet: A Flowrate sensor (Fluigent, XL) was thoroughly cleaned by rinsing with 70% ethanol, followed by incubation with hypochlorite (Glorix) for 20 min. After incubation the sensor was subsequently rinsed with 10 ml ddH 2 0, 10 ml propanol and dried with nitrogen.

Techniques: Transferring, Cell Culture

Journal: bioRxiv

Article Title: Pressure-driven perfusion system to control, multiplex and recirculate cell culture medium for Organs-on-Chips

doi: 10.1101/2022.07.21.500785

Figure Lengend Snippet: (a) Schematic of the fluidic circuit used shows the microfluidic analogy of the Graetz bridge used in an AC/DC convertor using check-valves, if the pressure in R1 is higher than R2, fluidic flow follows the gray arrows. When the pressure is reversed, fluidic flow follows the black arrows, remaining unidirectional at Q1 and bidirectional a Q2 (b) direct measurement of the recirculation. When pressure commands are reversed, the flow is reversed at flowrate sensor Q2, however, remains unidirectional at flowrate sensor Q1 (c) High resolution recording of the pressure switch at the fluidic reservoirs shows small overshoot and undershoot in pressure resulting in spike in flowrate. Interestingly EZ1 vents slower than EZ2 affecting the algorithm (d) Measured flowrate shows the overshoot due to the pressure overshoot and settling time of approximately 4 seconds, due to the venting lag of EZ1 settling time is approximately 8 secs. See video S1 to see perfusion of suspended micro beads during switching.

Article Snippet: A Flowrate sensor (Fluigent, XL) was thoroughly cleaned by rinsing with 70% ethanol, followed by incubation with hypochlorite (Glorix) for 20 min. After incubation the sensor was subsequently rinsed with 10 ml ddH 2 0, 10 ml propanol and dried with nitrogen.

Techniques:

Journal: bioRxiv

Article Title: Pressure-driven perfusion system to control, multiplex and recirculate cell culture medium for Organs-on-Chips

doi: 10.1101/2022.07.21.500785

Figure Lengend Snippet: (a) Schematic of the used fluidic circuit shows the FCB with 6 channels connected. The free channels were blocked using a dummy chip (b) Pressure difference relationship for a single channel (green plot) and six channels in parallel (blue plot). The measurements show correlation with the predicted values (Figs.s4); however, the six channels in parallel show a 5-fold increase in flowrate dependence but this can be attributed to the tolerances of the fabricated FCB.

Article Snippet: A Flowrate sensor (Fluigent, XL) was thoroughly cleaned by rinsing with 70% ethanol, followed by incubation with hypochlorite (Glorix) for 20 min. After incubation the sensor was subsequently rinsed with 10 ml ddH 2 0, 10 ml propanol and dried with nitrogen.

Techniques:

Journal: bioRxiv

Article Title: Pressure-driven perfusion system to control, multiplex and recirculate cell culture medium for Organs-on-Chips

doi: 10.1101/2022.07.21.500785

Figure Lengend Snippet: (a) Schematic of the used fluidic circuit shows a single sample. For this experiment ddH 2 0 was used to demonstrate the functionality of the software in maintaining constant flowrate without the effect of sensor fouling (b) Flowrate and pressure difference for 4 minutes during a flow reversal shows little variation (c) two day perfusion using ddH 2 O shows minimal variation. Error band shows the interquartile range of that time segment.

Article Snippet: A Flowrate sensor (Fluigent, XL) was thoroughly cleaned by rinsing with 70% ethanol, followed by incubation with hypochlorite (Glorix) for 20 min. After incubation the sensor was subsequently rinsed with 10 ml ddH 2 0, 10 ml propanol and dried with nitrogen.

Techniques: Software

Journal: bioRxiv

Article Title: Pressure-driven perfusion system to control, multiplex and recirculate cell culture medium for Organs-on-Chips

doi: 10.1101/2022.07.21.500785

Figure Lengend Snippet: (a) Used fluidic circuit (b) Applying a fixed Pressure difference results in a constant decrease of the flowrate per displaced volume due to effect of P head .(b) Fixed flowrate shows a steady increase in applied pressure due to the changing P head using fixed flowrate.

Article Snippet: The Fluigent-compatible flowrate sensor is a thermal mass-based and commonly used for high accuracy lab-on-a-chip purposes.

Techniques:

Journal: bioRxiv

Article Title: Pressure-driven perfusion system to control, multiplex and recirculate cell culture medium for Organs-on-Chips

doi: 10.1101/2022.07.21.500785

Figure Lengend Snippet: (a) Schematic of the fluidic circuit used to validate sensor accuracy. A 10 ml serologic pipette was attached to the outlet of the circuit and the pressure controller was set to a fixed flowrate using the internal PID-loop. At multiple intervals, time was noted and the flowrate was calculated (b) A clean sensor accurately measures the flowrate of cell culture medium (orange plot); after two days of continuous perfusion, the sensor becomes inaccurate(blue plot)

Article Snippet: The Fluigent-compatible flowrate sensor is a thermal mass-based and commonly used for high accuracy lab-on-a-chip purposes.

Techniques: Transferring, Cell Culture

Journal: bioRxiv

Article Title: Pressure-driven perfusion system to control, multiplex and recirculate cell culture medium for Organs-on-Chips

doi: 10.1101/2022.07.21.500785

Figure Lengend Snippet: (a) Schematic of the fluidic circuit used shows the microfluidic analogy of the Graetz bridge used in an AC/DC convertor using check-valves, if the pressure in R1 is higher than R2, fluidic flow follows the gray arrows. When the pressure is reversed, fluidic flow follows the black arrows, remaining unidirectional at Q1 and bidirectional a Q2 (b) direct measurement of the recirculation. When pressure commands are reversed, the flow is reversed at flowrate sensor Q2, however, remains unidirectional at flowrate sensor Q1 (c) High resolution recording of the pressure switch at the fluidic reservoirs shows small overshoot and undershoot in pressure resulting in spike in flowrate. Interestingly EZ1 vents slower than EZ2 affecting the algorithm (d) Measured flowrate shows the overshoot due to the pressure overshoot and settling time of approximately 4 seconds, due to the venting lag of EZ1 settling time is approximately 8 secs. See video S1 to see perfusion of suspended micro beads during switching.

Article Snippet: The Fluigent-compatible flowrate sensor is a thermal mass-based and commonly used for high accuracy lab-on-a-chip purposes.

Techniques:

Journal: bioRxiv

Article Title: Pressure-driven perfusion system to control, multiplex and recirculate cell culture medium for Organs-on-Chips

doi: 10.1101/2022.07.21.500785

Figure Lengend Snippet: (a) Schematic of the used fluidic circuit shows the FCB with 6 channels connected. The free channels were blocked using a dummy chip (b) Pressure difference relationship for a single channel (green plot) and six channels in parallel (blue plot). The measurements show correlation with the predicted values (Figs.s4); however, the six channels in parallel show a 5-fold increase in flowrate dependence but this can be attributed to the tolerances of the fabricated FCB.

Article Snippet: The Fluigent-compatible flowrate sensor is a thermal mass-based and commonly used for high accuracy lab-on-a-chip purposes.

Techniques:

Journal: bioRxiv

Article Title: Pressure-driven perfusion system to control, multiplex and recirculate cell culture medium for Organs-on-Chips

doi: 10.1101/2022.07.21.500785

Figure Lengend Snippet: (a) Schematic of the used fluidic circuit shows a single sample. For this experiment ddH 2 0 was used to demonstrate the functionality of the software in maintaining constant flowrate without the effect of sensor fouling (b) Flowrate and pressure difference for 4 minutes during a flow reversal shows little variation (c) two day perfusion using ddH 2 O shows minimal variation. Error band shows the interquartile range of that time segment.

Article Snippet: The Fluigent-compatible flowrate sensor is a thermal mass-based and commonly used for high accuracy lab-on-a-chip purposes.

Techniques: Software

Journal: Cancer Research

Article Title: A Microfluidic Cancer-on-Chip Platform Predicts Drug Response Using Organotypic Tumor Slice Culture

doi: 10.1158/0008-5472.CAN-21-0799

Figure Lengend Snippet: Microfluidic CoC platform design and overview. A, Top view of the microfluidic chip illustrating its components: the PDMS film in which the microfluidics are embedded, the silicon frame, which includes the inlet and outlet to the channels in the film. Scale bar, 2.5 mm. B, Vertical cross-section of the microfluidic chip. The PDMS film with the microfluidic channel is supported by a silicon frame, which includes a well facing the PDMS layer. The microchannel and the well are separated by a microporous PDMS membrane (4-μm pore size). Scale bar, 100 μm. C, Representation of the CoC platform. The platform, which consists of a bottom and a top plate, houses the microfluidic chip and allows for its connection to external fluidics. The ring is used to seal the system, to maintain adequate pressure for the controlled flow within the fluidic channel, and to minimize leakage. Scale bar, 2 cm. D, Accessories of the CoC platform with two different top plate designs. We have used double flow for this study. E, Cross-section of CoC illustrating the diffusion and perfusion toward the tissue slice. First the tissue slice is added to the microfluidic chip, which is in turn sandwiched between the top and bottom plates and connected to the external pump. Breast PDX tissue slices were perfused with an inlet flowrate of 5 μL/minute through the top and bottom channels. F, CoC platform connected to Fluigent Microfluidic flow control system that was further connected to flowrate sensors (Fluigent FLOW UNIT-S) using Fluigent MAT for the entire culture period.

Article Snippet: The flow rate was maintained by a pressure-driven microfluidic flow control system (Fluigent MFCS TM -EZ) and monitored by flowrate sensors (Fluigent FLOW UNIT-S) using Fluigent Microfluidic Automation Tool (MAT) for the entire culture period.

Techniques: Membrane, Pore Size, Diffusion-based Assay, Control