Biomedical Applications of Nanodiamond (Review)

The interest in nanodiamond applications in biology and medicine is on the rise over recent years. This is due to the unique combination of properties that nanodiamond provides. Small size (~5 nm), low cost, scalable production, negligible toxicity, chemical inertness of diamond core and rich chemistry of nanodiamond surface, as well as bright and robust fluorescence resistant to photobleaching are the distinct parameters that render nanodiamond superior to any other nanomaterial when it comes to biomedical applications. The most exciting recent results have been related to the use of nanodiamonds for drug delivery and diagnostics—two components of a quickly growing area of biomedical research dubbed theranostics. However, nanodiamond offers much more in addition: it can be used to produce biodegradable bone surgery devices, tissue engineering scaffolds, kill drug resistant microbes, help us to fight viruses, and deliver genetic material into cell nucleus. All these exciting opportunities require an in-depth understanding of nanodiamond. This review covers the recent progress as well as general trends in biomedical applications of nanodiamond, and underlines the importance of purification, characterization, and rational modification of this nanomaterial when designing nanodiamond based theranostic platforms

Salt-Assisted Ultrasonic Deaggregation of Nanodiamond

We report a new facile, inexpensive, and contaminant-free technique of salt-assisted ultrasonic deaggregation (SAUD) of nanodiamond into single-digit particles stable in aqueous colloidal solution in a wide pH range. The technique utilizes the energy of ultrasound to break apart nanodiamond aggregates in sodium chloride aqueous slurry. In contrast to current deaggregation techniques, which introduce zirconia contaminants into nanodiamond, the single-digit nanodiamond colloids produced by SAUD have no toxic or difficult-to-remove impurities and are therefore well-suited to produce nanodiamonds for numerous applications, including theranostics, composites, and lubrication, etc. Requiring only aqueous slurry of sodium chloride and standard horn sonicator, and yielding highly pure well-dispersed nanodiamond colloids, the technique is an attractive alternative to current nanodiamond deaggregation protocols and can be easily implemented in any laboratory or scaled up for industrial use

Insights into the Effects of Electrolyte Composition on the Performance and Stability of FeF 2 Conversion-Type Cathodes

As an alternative to commercial Ni- and Co-based intercalation-type cathode materials, conversion-type metal fluoride (MF x ) cathodes are attracting more interest due to their promises to increase cell-level energy density when coupled with lithium (Li) or silicon (Si)-based anodes. Among metal fluorides, iron fluorides (FeF 2 and FeF 3 ) are regarded as some of the most promising candidates due to their high capacity, moderately high potential and the very low cost of Fe. In this study, the impacts of electrolyte composition on the performance and stability of nanostructured FeF 2 cathodes are systematically investigated. Dramatic impacts of Li salt composition, Li salt concentration, solvent composition, and cycling potential range on the cathode's most critical performance parameters-stability, capacity, rate, and voltage hysteresis are discovered. In contrast to previous beliefs, it is observed that even if the Fe 2+ cation dissolution could be avoided, the dissolution of F ? anions may still negatively affect cathode performance. Formation of the more favorable cathode solid electrolyte interface (CEI) is found to minimize both processes.Different aspects of this work were supported by the Army Research Office (ARO grant number W911NF-12-1-0259) and by the Qatar National Research Fund under its National Priorities Research Program (grantnumber NPRP7-567-2-216). The authors also acknowledge fellowship support of Q.H. and X.R. by the China Scholarship Council.Scopu