Asymmetric Capillary Membrane Dialyzer for Pathogen Removal
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Solution Overview
Problem
Conventional dialysis machines fail to effectively filter out viruses and bacteria from the blood due to their membrane structure, which allows these pathogens to remain in the bloodstream.
Innovation Solution
The dialysis machine reverses the conventional direction of ultrafiltration by guiding the blood circuit along the outer surface of capillary membranes with larger pores, allowing viruses, bacteria, and endotoxins to be caught and removed, while the dialysate circuit flows through the inner surface with smaller pores, enhancing the absorption area for toxin removal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional dialysis machines use standard capillary membranes with uniform pore sizes, then the dialysis process can be performed in a conventional manner, but viruses and bacteria cannot be effectively filtered from the blood
Solution Approach 1:
The capillary membrane is designed with asymmetric pore distribution, where the outer surface has larger pores (1-4 μm) for trapping viruses and bacteria, while the inner surface has smaller pores (<5 nm) for conventional dialysis. This local differentiation of pore sizes allows the membrane to perform multiple functions simultaneously without requiring completely separate membrane structures.
Solution Approach 2:
The invention inverts the conventional ultrafiltration direction by guiding blood to flow along the outer surface of the capillary membrane rather than through the lumen. This reversal allows blood-derived pathogens to be trapped at the outer surface with larger pores while maintaining conventional dialysis function at the inner surface.
2Productivity
If the blood circuit is guided through the lumen of capillary membranes, then conventional dialysis can be performed, but the absorption area for toxin removal is limited
Solution Approach 1:
The invention inverts the conventional circuit configuration by guiding blood to flow along the outer surface of capillary membranes rather than through the lumen. This reversal increases the effective absorption area by approximately 1,500 m² and allows pathogens to be trapped at the outer surface while maintaining conventional dialysis function at the inner surface.
Solution Approach 2:
The invention transitions from one-dimensional flow through the lumen to two-dimensional flow along the outer surface of the capillary membranes. This dimensional change significantly increases the contact area between blood and membrane, enhancing toxin removal efficiency without requiring additional membrane surface area.
3Reliability
If the blood circuit flows along the outer surface of capillary membranes with larger pores, then viruses and bacteria can be trapped and removed, but the configuration becomes more complex compared to conventional dialysis
Solution Approach 1:
The asymmetric membrane structure with differentiated pore sizes at outer and inner surfaces allows localized optimization for pathogen trapping without requiring complete redesign of the entire dialysis system. The larger outer pores specifically target pathogens while the smaller inner pores maintain conventional dialysis function.
Solution Approach 2:
The asymmetric capillary membrane serves multiple functions simultaneously: it acts as a barrier to trap viruses and bacteria at the outer surface while maintaining conventional dialysis function at the inner surface. This multi-functionality is achieved within a single membrane structure rather than requiring separate components.
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 configuration increases the absorption area by approximately 1,500 m², effectively trapping and removing large-molecular toxins, bacteria, and viruses from the blood, improving the dialysis process by utilizing the larger pores on the outer surface for adsorption and size exclusion.
Implementation Method 1
the invention makes use of the idea of reversing the conventional direction of ultrafiltration along the capillary membranes of the dialyzer
Implementation Method 2
Viruses, bacteria and endotoxins can get caught in the larger pores during ultrafiltration from the outside in and can thus be removed from the patient's blood by adsorption or size exclusion
Implementation Method 3
Viruses, bacteria and endotoxins can get caught in the larger pores during ultrafiltration from the outside in and can thus be removed from the patient's blood by adsorption or size exclusion
Implementation Method 4
high-flux dialysis benefits not only from the large pore sizes but also from convective (filtrate drag - solvent drag) processes
Implementation Method 5
in low-flux dialysis the blood is washed mainly on the basis of diffusive processes
Data Source
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AI summary
The invention relates to a dialysis apparatus comprising a dialyzer (4) that includes a cluster of capillary membranes (8), each of which has an outer face (13) and an inner face (14), the mean pore size being larger in the area of the outer face (13) than in the area of the inner face (14), further comprising a blood circulation system (6) and a dialysate circulation system (7), the blood circulation system (6) extending along the outer faces (13) and the dialysate circulation system (7) extending along the inner faces (14).