DNA Aptamers That Bind to Alginate Hydrogels.

Area of Science:

• Biomaterials Science
• Drug Delivery Systems
• Molecular Biology

Background:

• Hydrogels are widely used in wound treatment due to their biocompatibility and healing promotion.
• The porous nature of hydrogels leads to rapid diffusion of encapsulated therapeutics, limiting their effectiveness.
• Aptamers, specific DNA/RNA sequences, offer a potential solution for controlled therapeutic release.

Purpose of the Study:

• To develop DNA aptamers capable of binding to alginate hydrogels.
• To investigate the potential of these aptamers as tethers for therapeutics to control diffusion.
• To evaluate the efficacy of aptamer-tethered therapeutics in extended drug delivery.

Main Methods:

• An in vitro selection method was employed to identify DNA aptamers targeting alginate hydrogels.
• The binding affinity and specificity of selected aptamers to alginate hydrogels were assessed.
• Aptamers were conjugated to bovine serum albumin (BSA) to test their functionality as tethers in diffusion studies.

Main Results:

• Two DNA aptamers were identified that bind to alginate hydrogels across a concentration range of 0.5-2%.
• These aptamers demonstrated specificity for alginate over agarose.
• Aptamer-conjugated BSA exhibited significantly longer retention within hydrogels over a one-week period, irrespective of encapsulation or post-gelation introduction.

Conclusions:

• Developed DNA aptamers effectively bind alginate hydrogels, serving as versatile tethers for therapeutic molecules.
• These aptamers enable sustained drug delivery by preventing premature diffusion from hydrogel matrices.
• The findings offer a flexible strategy for enhancing therapeutic outcomes in hydrogel-based wound treatments.