Immunoassay on free-standing electrospun membranes

Area of Science:

• Biomaterials Science
• Analytical Chemistry
• Immunotechnology

Background:

• Electrospun membranes offer unique properties for bioassays.
• Poly(epsilon-caprolactone) (PCL) fibers provide tenacity, flexibility, and suitable surface energy.
• Protein adsorption via hydrophobic interactions is crucial for immunoassay sensitivity.

Purpose of the Study:

• To develop a highly sensitive immunoassay platform using electrospun PCL membranes.
• To investigate the impact of membrane processing on immunoassay performance.
• To compare the sensitivity of electrospun membranes with conventional immunoassay materials.

Main Methods:

• Fabrication of nonwoven PCL fiber membranes via electrospinning.
• Modification of membrane porosity and thickness through a fold-and-press process.
• Quantification of protein adsorption and fluorescence signal enhancement.
• Establishment of immunoassay parameters including linear detection range and limit of detection (LOD) using anti-HSA and HSA-FITC.

Main Results:

• The fold-and-press process reduced membrane porosity to <10% and increased thickness to 280 microm, enhancing fluorescence signal >120x.
• A linear detection range from 500 ng/mL down to 1 ng/mL was achieved.
• The limit of detection (LOD) was approximately 0.08 ng/mL, significantly lower than conventional nitrocellulose or unprocessed PCL membranes (approx. 100 ng/mL).

Conclusions:

• Electrospun PCL membranes provide a sensitive and efficient platform for immunoassays.
• The processed membranes combine the simplicity of conventional assays with the high sensitivity of advanced bioassays.
• This technology holds promise for low-cost, high-performance diagnostic applications.