Related Experiment Video
Updated: Apr 28, 2026
Preparation of Multifunctional Silk-Based Microcapsules Loaded with DNA Plasmids Encoding RNA Aptamers and Riboswitches
Published on: October 8, 2021
Silk fibroin layer-by-layer microcapsules for localized gene delivery
Linhao Li1, Sebastian Puhl2, Lorenz Meinel2
1Institute for Pharmacy and Food Chemistry, University of Wuerzburg, Am Hubland, 97074 Wuerzburg, Germany; Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, 400030 Chongqing, PR China.
Silk fibroin microcapsules effectively deliver plasmid DNA (pDNA) for gene therapy applications. These novel microcapsules show low cytotoxicity and high transfection efficiency, offering a promising alternative for localized pDNA delivery.
Area of Science:
- Biomaterials Science
- Nanotechnology
- Gene Delivery Systems
Background:
- Plasmid DNA (pDNA) delivery is crucial for gene therapy, but efficient and safe delivery vectors remain a challenge.
- Silk fibroin (SF) is a biocompatible natural polymer with tunable properties, making it a potential material for drug and gene delivery.
- Layer-by-layer assembly offers precise control over microcapsule structure and functionality.
Purpose of the Study:
- To develop and characterize silk fibroin (SF) microcapsules for plasmid DNA (pDNA) delivery.
- To evaluate the in vitro pDNA release kinetics, cytotoxicity, and transfection efficiency of SF microcapsules.
- To compare the performance of SF microcapsules with conventional pDNA delivery complexes.
Main Methods:
- Fabrication of hollow SF microcapsules using layer-by-layer assembly on polystyrene templates.
- Loading of plasmid DNA encoding enhanced green fluorescent protein (eGFP) via incorporation or surface adsorption.
- In vitro assessment of pDNA release, cytotoxicity (MTT assay), and eGFP expression in cells.
- Characterization of microcapsule size, shell thickness, and surface properties.
Main Results:
- Monodisperse and structurally stable SF microcapsules of controllable size and shell thickness were successfully fabricated.
- Sustained pDNA release over 3 days was achieved, with accelerated release in the presence of protease.
- SF microcapsules demonstrated efficient cell transfection with significantly lower cytotoxicity compared to pDNA/branched polyethylenimine complexes.
- Optimal transfection efficiency was observed with 1 μm SF microcapsules featuring surface-adsorbed pDNA.
Conclusions:
- Silk fibroin microcapsules are a viable and effective platform for localized pDNA delivery.
- The developed SF microcapsules offer a promising combination of low cytotoxicity and high transfection efficiency.
- These findings support the potential of SF microcapsules in advancing gene therapy applications.
