Effect of oil-water interface and payload-DNA interactions on payload-encapsulated DNA nanogels

Herein, we investigated the influence of emulsion process and DNA sequence on the morphology and surface property of the as-fabricated gel particles with and without payload. Nanogels can be prepared by using synthetic and kiwifruit-derived DNA above a certain concentration whilst nanocapsules can only be prepared by using a synthetic 19-mer DNA containing A nitrogen base. Kiwifruit-derived DNA was used to encapsulate two payloads, which were DOX and lipase, via oil-in-water and water-in-oil processes. The oil-water interface and payload-DNA interactions dictated their size, surface property, and payload encapsulation. The DOX-encapsulated nanogels exhibited comparable payload encapsulation regardless the emulsion process because DOX would not only intercalate in the DNA but also bind with the negatively charged DNA. The lipase-encapsulated nanogels prepared via oil-in-water process exhibited higher payload encapsulation and activity than those via water-in-oil process due to its hydrophobic nature and the creation of oil-water interface. Moreover, the advantage of enzyme encapsulation was revealed in the case at acidic solution pH. This study revealed the importance of the oil-water interface and payload-DNA interactions on the preparation of payload-encapsulated DNA nanogels.