DRUG DELIVERY SYSTEM FOR ION CHANNEL SCREENING
The Dynaflow® Resolve system is an add-on to your existing patch-clamp setup that offers solution exchange at unsurpassed speed, control, and flexibility.
The system allows for recording of any ion channel current in any patch-clamp recording configuration. You can use all type of cells and all kinds of compounds that are required for your successful experiments.
Contact us if you need more information at email@example.com
- True versatility
Works with any cell type, any patch-clamp configuration, and any type of ion channel from single-cell channel recordings to secondary screening.
- Complex perfusion protocols
Rapid solution exchange (low millisecond range) enables analysis of fast kinetics.
- Low compound consumption and reusable chip
Allows long experiments with less than 150 μl, minimizing compound and buffer consumption.
- Optimized for safety pharmacology
Enables long experiments and long exposure times. Optimized for sticky compounds and designed for cumulative dose-response.
- Maximized data quality
Numerous cells per chip. Multiple compounds analyses per chip. Full dose-response for every compound. Gigaseal recordings with superior experimental control.
The system includes a motorized scan stage with stage controller and a joystick, a syringe pump to drive the flow in the microfluidic chip, as well as the Dynaflow® Commander software. It fully integrates with most inverted microscopes.
A system contains:
1 – Dynaflow® Resolve Chip
The Dynaflow® Resolve chip has 16 microchannels and is composed of a glass microfluidic chip and a plastic interface forming the wells and the recording chamber. The chip is reusable and developed to reduce the risk for non-specific binding of “sticky compounds” and offering improved cost-efficiency through low compound consumption.
2 – Syringe Pump
A easy setup syringe pump especially designed to drive the flow in the Dynaflow® Resolve chip.
3 – Motorized Scan Stage with Stage Controller and Joystick
A motorized scan stage is used to automatically translate chip movements. It includes a stage controller and a joystick and it is controlled by the Dynaflow® Commander software.
4 – Dynaflow® Commander Software
The Commander software assures control and pre-programming of the movements of the scan stage. It synchronizes precision solution exchange with real time tagging of the acquired data. The Windows-based Dynaflow® Commander software allows a full control of experiments, including scan protocols, exposure times and instant protocol changes.
Probing Structure and Function of Ion Channels Using Limited Proteolysis and Microfluidics View paper >>
Glycine/Serine Polymorphism at Position 38 Influences KCNE1 Subunit’s Modulatory Actions on Rapid and Slow Delayed Rectifier K+ Currents View paper >>
Kinetics of drug interaction with the Kv11.1 potassium channel View paper >>
Effect of cholesterol depletion on the pore dilation of TRPV1 View paper >>
Sub-anesthetic concentrations of (R,S)-ketamine metabolites inhibit acetylcholine-evoked currents in α7 nicotinic acetylcholine receptors View paper >>
A method for bidirectional solution exchange—“Liquid bullet” applications of acetylcholine to α7 nicotinic receptors View paper >>
Alternatively spliced domains interact to regulate BK potassium channel gating View paper >>
AF-353, a novel, potent and orally bioavailable P2X3/P2X2/3 receptor antagonist View paper >>
Arrangement of Kv1 α subunits dictates sensitivity to tetraethylammonium View paper >>
Novel Alpha-7 Nicotinic Acetylcholine Receptor Agonists Containing a Urea Moiety: Identification and Characterization of the Potent, Selective, and Orally Efficacious Agonist 1-[6-(4-Fluorophenyl)pyridin-3-yl]-3-(4-piperidin-1-ylbutyl) Urea (SEN34625/WYE-103914) View paper >>
Telithromycin blocks neuromuscular transmission and inhibits nAChR currents in vitro View paper >>
MEC-2 and MEC-6 in the Caenorhabditis elegans Sensory Mechanotransduction Complex: Auxiliary Subunits that Enable Channel Activity View paper >>
Differential Structure of Atrial and Ventricular KATP Atrial KATP Channels Require SUR1 View paper >>
Role of cAMP sensor Epac as a determinant of K-ATP channel ATP-sensitivity in human pancreatic beta cells and rat INS-1 cells View paper >>
Gain-of-Function Mutations in the MEC-4 DEG/ENaC Sensory Mechanotransduction Channel Alter Gating and Drug Blockade View paper >>
Controlling Desensitized States in Ligand-Receptor Interaction Studies with Cyclic Scanning Patch-Clamp Protocols View paper >>
A Biohybrid Dynamic Random Access Memory View paper >>
An isoflurane- and alcohol-insensitive mutant GABAA receptor 1 subunit with near normal apparent affinity for GABA: characterization in heterologous systems and production of knock-in mice View paper >>
Blocking Characteristics of hERG, hNav1.5, and hKvLQT1/ hminK after Administration of the Novel Anti-Arrhythmic Compound AZD7009 View paper >>
Microfluidic device for creating gradients View paper >>
A chemical waveform synthesizer View paper >>
Microfluidic technologies in drug discovery View paper >>
Patch clamp electrophysiology steps up a gear View paper >>
Microfluidic Gradient Generating Device for Pharmacological Profiling View paper >>
Blocking characteristics of hKv1.5 and hKv4.3/hKChIP2.2 after administration of the novel antiarrhythmic compound AZD7009 View paper >>
A Microfluidics Approach to the Problem of Creating Separate Solution Environments Accessible from Macroscopic Volumes View paper >>
Stabilization of High-Resistance Seals in Patch-Clamp Recordings by Laminar Flow View paper >>
Automated Electrophysiology: High Throughput of Art View paper >>
A Cell-Based Bar Code Reader for High-Throughput Screening of Ion Channel-Ligand Interactions View paper >>
Screening of ion channel receptor agonists using capillary electrophoresis-patch clamp detection with resensitized detector cells View paper >>
“We use the Dynaflow Resolve in the context of drug-profiling at the NMI-TT Pharmaservices. It is a very reliable and efficient tool for automated compound application with excellent performance in fast solution exchange. The new reusable glass chip design offers improved performance with sticky compounds, so that we now started to use it in safety pharmacology studies, where the highest standards in accuracy of compound application have to be met.”
“We bought the Dynaflow Resolve system because we needed a manual patch clamp system with reliable and fast solution application.
Compared to our conventional patch clamp system, the Dynaflow offers:
- low solution quantity demand,
- fast solution exchange,
- reliable drug application.
In conclusion, after several years of use, we are satisfied with the Dynaflow Resolve system. It provides reliable and fast solution exchange. It is especially suitable for detailed characterization of drug effects on ion channel function.”
“We believe that the Dynaflow Resolve System is the most easy to use, and robust, perfusion system available for whole cell patch-clamp recordings of isolated cells. We almost never have problems with unstable flows, and the solution exchange times are very reliable. The system is also easy to clean which minimize the risks of contamination of drugs compared to other tubing systems which are made of plastic materials”
Are there any requirements regarding instrumentation, i.e. does this system work with any conventional patch clamp set-up?
Yes, the Dynaflow® Resolve technology fully integrates with conventional patch clamp set-ups and with most inverted microscopes. Fluicell provides everything needed to run the Dynaflow® Resolve platform.
The Dynaflow® Resolve platform includes:
- The Dynaflow® Resolve chip and a mounting socket,
- A motorized scan stage with stage controller and a joystick,
- A syringe pump,
- A lid with connector and tubing to connect to the syringe pump,
- The Dynaflow®Commander software.
No, this type of chip will not work with an up-right microscope.
No, but the chip is very easy to fill with a manually operated syringe.
About 10 minutes, depending on how fast you perform the patch clamp procedure.
The lid is used directly to connect pressure source to all the channels. The plastic lid can easily be opened and resealed to the chip using two nuts and a rubber ring sealing. When the lid is attached, it encloses a common volume of air over all substance wells. By pressurizing this air through the lid, the flow is driven from each well and out into the recording chamber. Additionally the lid functions as a protective barrier, shielding both the user and the solutions.
3 kPa positive pressure is needed when using standard settings.
More details can be found in the Thesis “On Microfluidics in Biotechnology: New Devices and Applications” (Johan Pihl), p. 18-19.
The substance reservoirs hold 150 µl. This is sufficient for 90 min flow time with a flow-rate of 26 µl/min.
The flow rate is set to be approximatively 4 mm/s at the channel outlets.
The chip is composed of a glass microfluidic component and a plastic interface (PEEK) forming the wells and the recording chamber. The plastic interface has been treated with titanium first, then with silicon oxide to allow for even wetting. The bottom of the chip is made of hard anodised aluminium. The lid is made from polycarbonate, O rings and seals from Viton and tubing in Teflon. We are using material that is standard for biological applications.
Using a glass chip has several advantages such as reusability, reducing risk for non-specific binding of “sticky compounds” and non-absorption of highly hydrophobic compounds.
Yes, The Dynaflow® Resolve chip is reusable meaning that the chip is emptied and washed properly after every use.
The Dynaflow® Resolve chip needs to be washed after every use to remove any traces of components such as cell debris, particles, potential salt crystals, all of which can contaminate or block channels.
Overtime, regular cleanings are not sufficient to remove all traces of components within the chip and an annual refurbishment is necessary to maintain the chip.
This is not a problem when the cell is in the collimated flow zones, where only the substance that flows out of the channel is present. But, the cells present in the recording chamber will be affected by the compounds which flow out. If the flow has been running during a whole scan it is advisable to add new fresh cells. Additionally, the chamber should be rinsed thoroughly before applying new cells.
During which phases of the drug development process is the system applicable? Characterization and validation.
Concentration response curves, (EC50, IC50), receptor kinetics, receptor activation, thermodynamics of ligand binding.
Dynaflow® Resolve is used for target identification and validation, lead identification and optimization and preclinical assays.
Yes, it is possible to screen substances with or without re-sensitisation of receptor responses.
The number of substances one can screen per day with the Dynaflow® Resolve system depends very much on the character of experiments. As the chip is reusable, many assays can be performed per day.
Using the Dynaflow® Resolve technology you have unprecedented control of the following parameters:
– The composition of the solution surrounding the cell,
– The time the cell spends in the exposure zone.
By adding agonist free buffer in every other channel of the chip, an intermittent wash out between each agonist is established. The scan stage is easily programmed so that the time the cell spends in the rinsing buffer would be sufficient for reactivation of the ion channel receptors.
Both voltage and ligand gated ion channels, the system is very flexible.
Experimental control is an important issue. With the Dynaflow® resolve system, you always know the true molecular composition of the bioactive substances around the patch-clamped cell, as well as the exposure time and switching speed.
The cell should fit with in the diffusion zones of the collimated flow, and the size and shape of the cell determines the forces acting on the cell by the flow.
Apart from this, as long as a cell can be patch clamped and lifted, it can be employed together with the Dynaflow® Resolve system.
With the present system, the cells need to be dislodged from the surface if they are adherent. We recommend a few different methods for use such as; treatment with Ca2+ free buffers, trypsin or simple mechanical dissociation.
It is OK as long as the user feels comfortable with it. An internal control substance should always be used.
In our experiments, we have seen an effect of more stable seals and higher resistances when the cell is in the flow, due to the flow field pushing the cell against the tip, indicating that the seal becomes better using Dynaflow® Resolve System. Experiments have been performed for over 20 minutes.
Data suggests that the seal becomes stabilized by the flow which means increased stability in the measurements. However, viscous drag could become apparent at high acceleration of lateral movement.
Is the cell negatively affected, seen from a physiological point of view, by long measurement times?
This does not differ from conventional patch clamp and depends to a large extent on which ion channel systems are studied. Some ion channels are reconstituted in membrane without loss of function. Others need an “intracellular cocktail” in the buffer to function properly.