Altering Colloidal Surface Functionalization Using DNA Encapsulated Inside Monodisperse Gelatin Microsphere Templates

• Published in: Langmuir 2013-05, Vol.29 (18), p.5534-5539
• Main Authors: Hardin, James O, Fernandez-Nieves, Alberto, Martinez, Carlos J, Milam, Valeria T
• Format: Article
• Language: English
• Subjects: Capsules - chemistry; Chemistry; Colloidal state and disperse state; Colloids - chemistry; DNA - chemistry; Exact sciences and technology; Gelatin - chemistry; General and physical chemistry; Microspheres; Particle Size; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Surface Properties
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/la400280x

Soluble oligonucleotides are typically introduced to bulk solution to promote hybridization activity on DNA-functionalized surfaces. Here, an alternative approach is explored by encapsulating secondary target strands inside semipermeable colloidal satellite assemblies, then triggering their release at 37 °C for subsequent surface hybridization activity. To prepare DNA-loaded satellite assemblies, uniform gelatin microspheres are fabricated using microfluidics, loaded with 15 base-long secondary DNA targets, capped with a polyelectrolyte bilayer, and finally coated with a monolayer of polystyrene microspheres functionalized with duplexes comprised of immobilized probes and soluble, 13 base-long hybridization partner strands. Once warmed to 37 °C, secondary DNA targets are released from the gelatin template and then competitively displace the shorter, original hybridization partners on the polystyrene microspheres.