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Hollow Microneedle-based Sensor for Multiplexed Transdermal Electrochemical Sensing
Published on: June 1, 2012
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Synthetic biology-instructed transdermal microneedle patch for traceable photodynamic therapy
Gang He1, Yashi Li1, Muhammad Rizwan Younis1
1Marshall Laboratory of Biomedical Engineering, International Cancer Center, Laboratory of Evolutionary Theranostics (LET), School of Biomedical Engineering, Shenzhen University Health Science Center, Shenzhen, 518060, China.
Nature Communications
|October 20, 2022
Summary
This study introduces a novel microneedle patch for 5-aminolevulinic acid photodynamic therapy. It enhances tumor treatment by increasing protoporphyrin IX accumulation and monitoring oxygen levels, improving therapeutic outcomes.
Area of Science:
- Biomedical Engineering
- Synthetic Biology
- Nanotechnology
Background:
- 5-Aminolevulinic acid (ALA)-based photodynamic therapy (PDT) efficacy is limited by inefficient delivery and poor accumulation of protoporphyrin IX (PpIX).
- Tumor hypoxia and limited imaging navigation hinder optimal therapeutic parameter selection in ALA-PDT.
Purpose of the Study:
- To develop a transdermal theranostic microneedle patch for enhanced ALA-PDT.
- To improve intratumoral PpIX accumulation and enable real-time monitoring of therapeutic parameters.
Main Methods:
- Constructed a synthetic biology-based microneedle patch co-loading ALA and catalase within tumor acidity-responsive copper-doped calcium phosphate nanoparticles.
- Utilized in vivo fluorescence/photoacoustic duplex imaging for simultaneous monitoring of intratumoral oxygen saturation and PpIX metabolic kinetics.
- Investigated the role of catalase in reversing tumor hypoxia and modulating PpIX biosynthesis and efflux pathways.
Main Results:
- Catalase activity in vivo reversed tumor hypoxia, leading to enhanced PpIX accumulation.
- The system downregulated hypoxia-inducible factor-1α and ferrochelatase, blocking PpIX efflux.
- Upregulation of ALA-synthetase and provision of exogenous ALA boosted PpIX biosynthesis.
- Dual-mode imaging provided real-time feedback for optimizing therapeutic parameters.
Conclusions:
- The developed theranostic microneedle patch significantly enhances ALA-PDT efficacy by maximizing intratumoral PpIX enrichment.
- This approach offers a promising strategy for Ca2+/Cu2+-interferences-enhanced repeatable PDT with potential for clinical translation.
- Simultaneous imaging and therapeutic delivery pave the way for personalized cancer treatment optimization.
