Transdermal Cartridge with Spring-Driven Microneedle Assembly
Solution Overview
Problem
Current transdermal drug delivery systems using microneedle assemblies face challenges in providing a balanced delivery of drugs that require steady-state concentrations, such as insulin, as they often result in variable drug administration rates, which can be inefficient for maintaining consistent blood levels.
Innovation Solution
A drug delivery apparatus featuring a cartridge and microneedle assembly with a deformable membrane and a spring mechanism that allows for controlled penetration and fluid communication, enabling a steady and controlled release of the drug formulation into the skin, ensuring consistent delivery.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If transdermal drug delivery apparatus administer drugs at variable rates, then the device complexity is reduced, but the drug delivery consistency deteriorates
Solution Approach 1:
The microneedle assembly is designed to be movable relative to the cartridge, allowing dynamic adjustment of the delivery rate. The microneedles can penetrate to different depths and maintain contact with the skin for varying durations, enabling the system to deliver drugs at controlled variable rates while maintaining consistency through deliberate dynamic control rather than fixed static parameters
Solution Approach 2:
The system controls drug delivery by changing physical parameters such as microneedle penetration depth, contact time with skin, and applied pressure. These parameter variations allow the apparatus to achieve consistent drug delivery at different rates by deliberately controlling the physical state and motion of the microneedle assembly relative to the cartridge
2Stability of the object's composition
If transdermal drug delivery apparatus slowly administer drugs at a constant rate, then the drug delivery consistency is improved, but the device complexity increases
Solution Approach 1:
The apparatus utilizes the natural properties of the skin and microneedle-skin interaction to self-regulate drug delivery. The microneedles automatically penetrate the skin to a controlled depth and the drug delivery rate is self-regulated by the skin's absorption characteristics and the gradual depletion of drug from the cartridge, eliminating the need for complex external control mechanisms
Solution Approach 2:
The system maintains continuous drug delivery through sustained microneedle-skin contact. The microneedle assembly remains engaged with the skin throughout the treatment period, providing uninterrupted drug flow from the cartridge through the microneedles into the skin, ensuring consistent delivery without requiring complex intermittent activation mechanisms
3Productivity
If conventional subcutaneous delivery delivers large amounts of drug at one time, then the productivity is improved, but the drug delivery consistency deteriorates
Solution Approach 1:
The drug delivery system is segmented into multiple microneedles that deliver drug through separate pathways. The total drug dose is divided and delivered simultaneously through numerous individual microneedle channels, transforming a single large-volume injection into multiple smaller concurrent deliveries that collectively achieve the same productivity while maintaining steady blood concentration
Solution Approach 2:
The system transitions from conventional single-point subcutaneous injection to distributed multi-point transdermal delivery. By spreading the drug delivery across numerous microneedle insertion points on the skin surface, the system achieves equivalent or greater total drug delivery efficiency while the distributed nature of delivery prevents sudden spikes in blood concentration
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
The apparatus ensures a steady and controlled release of the drug, maintaining consistent blood levels and improving the efficacy of drugs like insulin by providing a balanced delivery over an extended period.
Implementation Method 1
a spring for forcing the microneedle assembly outwardly against the skin
Implementation Method 2
a deformable membrane and a spring mechanism that allows for controlled penetration and fluid communication
Data Source
Figure 1~3
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Figure 6~7
AI summary
A cartridge (16), which may be suitable for use as a portion of a transdermal drug delivery apparatus (10), may include a body (96) at least partially defining an interior for containing fluid for being delivered by the transdermal drug delivery apparatus (10). The body (96) may also at least partially define first and second openings to the interior of the body (96), wherein the first and second openings are respectively proximate opposite first and second ends of the body (96). The cartridge (16) may also include a self-sealing member (108) at least partially closing the first opening, and a movable member (116) at least partially closing the second opening, wherein at least a portion of the movable member (116) is for being urged into the interior of the body (96) for increasing pressure within the interior of the body (96).