Microneedle Array With pH Color Change Indicator
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing microneedle systems lack a reliable method to verify sufficient penetration into the skin's stratum corneum, as they often rely on indirect indicators or fail to provide immediate visual confirmation of penetration depth.
Innovation Solution
Incorporating a color change indicator, particularly a pH indicator, into the microneedle array that changes color visibly upon penetrating the skin's stratum corneum, allowing direct and immediate verification of penetration depth.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a microneedle array is used for intradermal delivery, then substance delivery into the skin is enabled, but reliable verification of penetration depth is not possible
Solution Approach 1:
The patent incorporates pH indicators that change color in response to pH variations between the skin surface and stratum corneum. The color change provides immediate visual confirmation that the microneedles have successfully penetrated the stratum corneum, directly resolving the verification problem without requiring additional monitoring systems.
Solution Approach 2:
The patent uses pH indicators as intermediary substances that mediate between the microneedle penetration event and the observable color change. These indicators respond to the pH gradient created by successful penetration, translating the physical penetration event into a visible signal that confirms delivery success.
2Loss of information
If dye is used to indicate penetration, then visualization is possible, but the dye only indicates substance release not actual penetration
Solution Approach 1:
The patent employs pH indicators that change color based on pH differences between skin layers, providing direct visual evidence of penetration into the stratum corneum. This approach precisely indicates the actual penetration event rather than merely showing substance release, thereby improving measurement precision of penetration depth.
3Reliability
If microcapsules with dye are used, then penetration indication is possible, but additional pressure is required to burst the capsules
Solution Approach 1:
The patent extracts the dye from microcapsules and integrates the pH indicator directly into the microneedle structure or delivery system. This eliminates the need for additional pressure to burst capsules, as the color change occurs immediately upon penetration due to direct exposure to the pH gradient, thereby simplifying operation.
4Loss of information
If indirect verification methods are used, then penetration can be inferred, but direct and immediate verification is not achieved
Solution Approach 1:
The patent uses pH indicators that provide immediate visual feedback through color change as soon as the microneedles penetrate the stratum corneum and encounter the different pH environment. This direct verification eliminates the time delay associated with indirect methods and provides real-time confirmation of successful penetration.
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
Enables clear and immediate visualization of successful penetration into the stratum corneum, ensuring effective delivery of substances by providing a visible color change that indicates successful skin penetration.
Implementation Method 1
the pH value on the skin surface is 4 to 5.5 and, by comparison, the pH value of the stratum corneum is 6.5 to 7. Using a pH indicator, it is consequently possible to generate a visible color change during the passage from the skin surface into the stratum corneum
Data Source
AI summary
The invention relates to a microneedle array and to the use thereof for intradermal delivery, comprising a plurality of microneedles on a carrier, wherein this microneedle array is suitable for penetrating the skin of humans or animals and includes at least one color change indicator.