Peptide nucleic acid–nanodiamonds: covalent and stable conjugates for DNA targeting

Abstract

et al.. Peptide nucleic acid-nanodiamonds: covalent and stable conjugates for DNA targeting.This article highlights our recent application of functional nanodiamonds (NDs) with peptide nucleic acids (PNA) to develop tools for DNA detection. NDs appear as an ideal nanocarrier due to their versatile surface chemistry, their non-cytotoxicity and since they could benefit from intrinsic luminescent properties. In this work, we report for the first time the possibility to prepare a covalent, stable and functional conjugate of PNA with 20 nm HPHT (High Pressure High Temperature) nanodiamonds. Peptide nucleic acid is a DNA mimic related to both peptides via its backbone and to nucleic acid via its bases. It binds more specifically and more strongly than DNA itself to either DNA or RNA. We have initiated a novel functionalization route based on an optimized amidation of ND carboxylic acid groups, to produce ND-PNA conjugates via an efficient, simple and reproducible method. We describe the synthesis and characterization of those conjugates. The covalent binding of the ND-PNA and the loading of nucleic acid grafted onto the NDs were performed using various characterization methods including FTIR, Kaiser tests and thermogravimetry. Then, ND-PNA conjugates were validated through a successful recognition of complementary DNA in a mixture, showing their efficiency toward nucleic acid detection. Moreover, the impact of ND-PNA on A 549 cells' viability was analysed with flow cytometry and showed an absence of ND-PNA conjugates cytotoxicity. Such nucleic acid-functionalized nanodiamonds offer a wide range of applications and namely the possibility to target and to recognize DNA.

Nanodiamonds: From Synthesis and Purification to Deposition Techniques, Hybrids Fabrication and Applications

“…These different strategies were recently reviewed [202]. Anti-cancer drugs [203], nucleic acids [87,204] and insulin [205] can be either electrostatically adsorbed onto NDs or covalently grafted [206,207]. Drug loading and its release by a response to a stimulus like the pH value [208][209][210] are current challenges.…”

Nanodiamond: A high impact nanomaterial

“…Unlike other nanocarbon species such as carbon nanotubes (CNTs), nanodiamonds feature a rich surface chemistry resulting from the synthesis and purification steps and this provides a platform for a number of subsequent functionalization schemes. A number of interesting functionalization schemes have been developed for tailoring the surface groups of NDs, including amino functionalities for bioapplications [60] and attachment of biotin [61], streptavidin [61,62], and peptide nucleic acids (PNA) [63], among others. These functionalities, and many others, demonstrate that NDs can be functionalized with a wide variety of groups, and are thus suitable for potential application in a number of environments -of particular interest is targeted delivery to cell membranes for imaging, drug delivery, or even surgery.…”

Electrocatalytic processes promoted by diamond nanoparticles in enzymatic biosensing devices

“…Until now, although they present a wide range of interesting properties, DNPs have been less employed for this purpose than the rest of the carbon nanomaterials. Among the properties that make them suitable candidates for biosensing can be mentioned [4][5][6][7]: i) their production at large-scale by detonation methods with a narrow size distribution and a moderate cost, ii) the presence on their surface, as a consequence of the production and purification methods, of several oxygenated functional groups, which facilitate the immobilization of biomolecules (peptide nucleic acids, antibodies, enzymes) [8][9][10][11] and iii) their biocompatibility and noncytotoxic nature.…”