Paper-Based Devices for Capturing Exosomes and Exosomal Nucleic Acids From Biological Samples.

Area of Science:

• Biotechnology
• Nanomedicine
• Analytical Chemistry

Background:

• Exosomes are nanovesicles containing disease biomarkers like microRNAs (miRNAs).
• Current diagnostic methods for exosomal miRNAs are complex and not suitable for point-of-care testing (POCT).
• There is a need for inexpensive, robust, and user-friendly tools for exosome and miRNA analysis in POCT settings.

Purpose of the Study:

• To develop a paper-based extraction kit for exosomes and exosomal miRNAs.
• To create an analytical system compatible with downstream nucleic acid detection for POCT.
• To establish an easy sample preparation method for exosomal miRNA analysis.

Main Methods:

• Paper-based immunoaffinity devices were created by immobilizing anti-CD63 antibodies on filter paper to capture exosomes.
• Paper-based silica devices with silica nanoparticles were used to trap nucleic acids from captured exosomes.
• Exosome concentrations were quantified using enzyme-linked immunosorbent assay (ELISA).
• MicroRNA 21 (miR-21) levels were determined using reverse transcription quantitative polymerase chain reaction (RT-qPCR).

Main Results:

• Paper-based immunoaffinity devices successfully captured and quantified exosomes from cell cultures.
• Paper-based silica devices effectively trapped exosomal nucleic acids.
• The developed kit demonstrated successful isolation of exosomes and exosomal nucleic acids from clinical samples like platelet-poor plasma and lesion fluid.

Conclusions:

• The developed paper-based kit provides a simple and effective method for exosome and exosomal nucleic acid isolation.
• This technology has potential for point-of-care diagnostic applications.
• The study successfully demonstrated the feasibility of paper-based devices for exosome and miRNA analysis in biological samples.