Fabrication of nanodiamonds modified with hyaluronic acid and chlorin e6 for selective photothermal and photodynamic tumor therapy

Designing functionalized nanodiamonds with hyaluronic acid-phospholipid conjugates for enhanced cancer cell targeting and fluorescence imaging capabilities

Nanomedicine aims to develop smart approaches for treating cancer and other diseases to improve patient survival and quality of life. Novel nanoparticles as nanodiamonds (NDs) represent promising candidates to overcome current limitations. In this study, NDs were functionalized with a 200 kDa hyaluronic acid-phospholipid conjugate (HA/DMPE), enhancing the stability of the nanoparticles in water-based solutions and selectivity for cancer cells overexpressing specific HA cluster determinant 44 (CD44) receptors. These nanoparticles were characterized by diffuse reflectance Fourier-transform infrared spectroscopy, Raman spectroscopy, and photoluminescence spectroscopy, confirming the efficacy of the functionalization process. Scanning electron microscopy was employed to evaluate the size distribution of the dry particles, while dynamic light scattering and zeta potential measurements were utilized to evaluate ND behavior in a water-based medium. Furthermore, the ND biocompatibility and uptake mediated by CD44 receptors in three different models of human adenocarcinoma cells were assessed by performing cytofluorimetric assay and confocal microscopy. HA-functionalized nanodiamonds demonstrated the advantage of active targeting in the presence of cancer cells expressing CD44 on the surface, suggesting higher drug delivery to tumors over non-tumor tissues. Even CD44-poorly expressing cancers could be targeted by the NDs, thanks to their good passive diffusion within cancer cells.

Applications of Fluorescent Nanodiamond in Biology

Fluorescent nanodiamond (FND) has emerged as a promising material in several multidisciplinary areas, including biology, chemistry, physics, and materials science. Composed of sp 3 ‐carbon atoms, FND offers superior biocompatibility, chemical inertness, a large surface area, tunable surface structure, and excellent mechanical characteristics. The nanoparticle is unique in that it comprises a high‐density ensemble of negatively charged nitrogen‐vacancy (NV − ) centers that act as built‐in fluorophores and exhibit a number of remarkable optical and magnetic properties. These properties make FND particularly well suited for a wide range of applications, including cell labeling, long‐term cell tracking, super‐resolution imaging, nanoscale sensing, and drug delivery. This article discusses recent applications of FND‐enabled developments in biology.

Nano-GeTe Embedded in a Three-Dimensional Carbon Sponge for Flexible Li-Ion and Na-Ion Battery Anodes

Among the germanium-based compounds, GeTe is a promising anode candidate that exhibits high theoretical capacity (856 mAh g^-1 vs Li⁺/Li and 401 mAh g^-1 vs Na⁺/Na) and low volume expansion during an ion intercalation/deintercalation process. Nevertheless, achieving good dispersion of metal-like GeTe in anode materials remains a significant challenge. Herein, hybrid GeTe/graphene (GeTe/G) is proposed as a highly efficient anode for LiBs and SiBs by facile ball milling. Pulverized GeTe is effectively anchored on peeled graphene sheets that can accelerate Li⁺ transport in electrodes as predicted by theoretical calculations and thus result in improved overall electrochemical performance. For instance, GeTe/G possesses a high reversible capacity of 478 mAh g^-1 under 0.1 A g^-1 in the 300th cycle. Moreover, by further cross-linking the GeTe/G using carbon nanotube (CNT) and carbon nanofiber pyrolysis from cotton cellulose, the as-prepared three-dimensional (3D) flexible anode possesses macropores that acted as positive channels favorably for ion transport. Remarkably, the as-prepared flexible 3D GeTe/G/CNT electrode with a thickness of 1050 μm exhibits a high reversible capacity of 451.4 mAh g^-1 (4.38 mAh cm^-2) vs Li⁺/Li and 372.5 mAh g^-1 (2.08 mAh cm^-2) vs Na⁺/Na, respectively, in the second cycle under 0.1 A g^-1. These results shed some light on the direct application of 3D flexible carbon sponge electrodes in high-performance LiBs/SiBs.