5 nm Detonation Nanodiamond Suspensions

Detonation nanodiamond (DND) is produced from the carbon contained in high-energy explosives. The characteristic size of primary particles formed in the detonation process is ~ 5 nm, which can be isolated from large tight aggregates formed during synthesis. Colloidal suspensions of detonation nanodiamond in both water and a variety of organic solvents have a wide range of uses, including:

  • (1) drug delivery research

  • (2) nanocomposite strengthening

  • (3) electroplating

  • (4) polishing

  • (5) oil and fuel additives

Technical Characteristics

Adámas offers 5 nm DND as colloidal suspensions in water, Ethylene Glycol (EG) and N-methyl pyrrolidone (NMP), though suspensions can be also made available in Polyalplaolefin (PAO) synthetic oil, Kerosene, and Glycerol (Gly). Primary particles of detonation nanodiamond offer a robust platform for the delivery of molecules or drugs, with an extremely high surface area to volume ratio (~350 m2 /g) and spherical shape (Figure 1).

The particles exhibit a rich surface chemistry, which can be easily modified and functionalized using standard reaction procedures. For most bioapplications, the presence of surface terminal carboxylic acid groups (-COOH) can be modified using standard carbodiimide chemistry (e.g. EDC/NHS) for the attachment of primary amine derivatives or proteins. Functional species can be covalently linked, or, in the case where molecule delivery is required, physically adsorbed to the particle surfaces. A typical FTIR spectra for DND is shown in Figure 2, with carbonyl peak at ~1770 cm -1 .

Figure 1: High Resolution TEM (HRTEM) image of primary particles of detonation nanodiamond.

5 nm series in DI water with positive and negative zeta potentials

5 nm particles are available with either positive or negative zeta potentials.  The negative zeta potential particles are enriched with carboxylic acid functional groups (-COOH) on their surfaces.  The positive zeta potential particles can have a variety of functional groups such as hydroxyls (-OH), ketones (-C=O), and amines (-NH2). A typical zeta potential for the negatively charged particles is around -40mV at pH ~7, whereas the positively charged particles have zeta potentials (+40mV) at pH ~5. Dynamic light scattering (DLS) size distributions for these two materials are shown in Figure 3. Both positive and negative zeta potential versions are sold in water suspensions at 10 mg/mL.

5 nm Particles in Organic Solvents

Owing to their small size and rich surface chemistry, 5 nm nanodiamond particles can be stabilized in a large number of different solvent systems. This versatility allows for rapid implementation into your specific application area where solvents other than water are desired. Stable suspensions in base oils and fuels such as polyalphaolefin (PAO) and kerosene can be used in machinery and automobile engines for enhanced fuel efficiency, whereas suspensions in glycerol can be used in biological and pharmaceutical applications. Few (if any) nanoparticle systems can offer this degree of versatility. NOTE: the PAO suspensions are mixed with proprietary dispersants which causes the particle size to increase. However, 5 nm particles are used as a precursor for these products.

Figure 2: FTIR of carboxylated 5 nm nanodiamond.

Figure 3: Typical size distributions of 5 nm DND in deionized water.