10779/crick.12639464.v1 Robert Edgington Robert Edgington Katelyn M Spillane Katelyn M Spillane George Papageorgiou George Papageorgiou William Wray William Wray Hitoshi Ishiwata Hitoshi Ishiwata Mariana Labarca Mariana Labarca Sergio Leal-Ortiz Sergio Leal-Ortiz Gordon Reid Gordon Reid Martin Webb Martin Webb John Foord John Foord Nicholas Melosh Nicholas Melosh Andreas T Schaefer Andreas T Schaefer Functionalisation of detonation nanodiamond for monodispersed, soluble DNA-nanodiamond conjugates using mixed silane bead-assisted sonication disintegration The Francis Crick Institute 2020 Chemical Phenomena DNA Dynamic Light Scattering Microscopy, Atomic Force Nanodiamonds Silanes Solubility Sonication Schaefer FC001153 Tolar FC001185 PC 0601 Biochemistry and Cell Biology 0299 Other Physical Sciences 2020-07-15 11:08:54 Journal contribution https://crick.figshare.com/articles/journal_contribution/Functionalisation_of_detonation_nanodiamond_for_monodispersed_soluble_DNA-nanodiamond_conjugates_using_mixed_silane_bead-assisted_sonication_disintegration/12639464 Nanodiamonds have many attractive properties that make them suitable for a range of biological applications, but their practical use has been limited because nanodiamond conjugates tend to aggregate in solution during or after functionalisation. Here we demonstrate the production of DNA-detonation nanodiamond (DNA-DND) conjugates with high dispersion and solubility using an ultrasonic, mixed-silanization chemistry protocol based on the in situ Bead-Assisted Sonication Disintegration (BASD) silanization method. We use two silanes to achieve these properties: (1) 3-(trihydroxysilyl)propyl methylphosphonate (THPMP); a negatively charged silane that imparts high zeta potential and solubility in solution; and (2) (3-aminopropyl)triethoxysilane (APTES); a commonly used functional silane that contributes an amino group for subsequent bioconjugation. We target these amino groups for covalent conjugation to thiolated, single-stranded DNA oligomers using the heterobifunctional crosslinker sulfosuccinimidyl 4-(N-maleimidomethyl)cyclohexane-1-carboxylate (Sulfo-SMCC). The resulting DNA-DND conjugates are the smallest reported to date, as determined by Dynamic Light Scattering (DLS) and Atomic Force Microscopy (AFM). The functionalisation method we describe is versatile and can be used to produce a wide variety of soluble DND-biomolecule conjugates.