Cell Sphere Dissociation Using Controlled Shear Stress Conduits
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for dissociating cell spheres into single cells are labor-intensive, time-consuming, and involve physical stress, making it difficult to efficiently expand therapeutic and malignant stem cells for research and regenerative medicine.
Innovation Solution
A system utilizing a peristaltic pump and conduits with specific inner diameters to impart controlled shear stress, allowing for continuous and automated dissociation of cell spheres into single cells, with conduits made from materials like polyether ether ketone (PEEK) and arranged within tubing to ensure effective cell separation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If manual physical trituration of aggregates through pipette tips is used, then dissociation of cell spheres into single cells is achieved, but the process becomes labor-intensive and time-consuming
Solution Approach 1:
The patent replaces manual mechanical trituration with an automated flow-based mechanical dissociation system. Cell aggregates are suspended in fluid and passed through a nozzle that applies controlled shear stress to dissociate cells, eliminating manual labor and significantly reducing processing time while maintaining effective dissociation.
Solution Approach 2:
The system enables self-service dissociation where the fluid flow automatically performs the dissociation function as cell aggregates pass through the nozzle. The process requires no manual intervention during operation, with the flow dynamics itself providing the dissociation force, thereby increasing productivity and reducing time loss.
2Ease of operation
If repeated shear stress is applied through manual pipetting, then cell spheres are dissociated, but cell viability is reduced due to harsh processing
Solution Approach 1:
The patent changes the parameters of shear stress application by controlling fluid flow rate, viscosity, and nozzle geometry to optimize the dissociation process. By adjusting these parameters, the system achieves effective cell separation while minimizing excessive shear stress that would harm cell viability, thus resolving the contradiction between dissociation effectiveness and cell survival.
Solution Approach 2:
The patent introduces fluid as an intermediary medium to transmit shear stress during dissociation. Instead of direct mechanical manipulation with pipettes, cells are dissociated through controlled fluid flow through a nozzle, which acts as an intermediary that distributes stress more uniformly and controllably, reducing localized harsh stress on individual cells.
3Productivity
If automated flow-based dissociation with controlled shear stress is used, then productivity and cell viability are improved, but device complexity increases
Solution Approach 1:
The patent segments the dissociation function into a dedicated nozzle component that can be integrated into existing bioreactor or culture systems. By separating the dissociation function into a distinct, modular element, the system achieves automated high-productivity dissociation without requiring complete system redesign, thus limiting the increase in overall device complexity.
Solution Approach 2:
The patent designs the flow-based dissociation system to be compatible with standard bioreactor and culture vessel configurations. The same fluid flow system can serve multiple functions including cell culture maintenance and dissociation, reducing the need for separate dedicated equipment and thereby limiting the increase in device complexity despite the automation benefits.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method enables efficient and automated dissociation of cell spheres, reducing cell stress and increasing viability, facilitating the expansion of stem cells for research and therapeutic applications.
Implementation Method 1
The conduits have an inner diameter that is sized to provide a shear stress to the fluid of between about 5 to about 60 dynes/cm2, which is sufficient for dissociating the spheres of cells passing through the conduits
Implementation Method 2
A peristaltic pump in fluid communication via tubing with a bioreactor in which cells are cultivated
Data Source
AI summary
Various implementations include systems and methods for automatically and continuously dissociating spheres of cells. In particular, one such system includes a peristaltic pump in fluid communication via tubing with a bioreactor in which cells are cultivated. A plurality of conduits are disposed within a portion of the tubing such that fluid flowing between the bioreactor and the pump passes through the conduits. The conduits have an inner diameter that is sized to provide a shear stress to the fluid of between about 5 to about 60 dynes/cm2, which is sufficient for dissociating the spheres of cells passing through the conduits. For example, each conduit may have an inner diameter of between about 50 and about 250 micrometers.