Accelerated Development of Hippocampal Neurons and Limited Adhesion of Astrocytes on Negatively Charged Surfaces

This work examines the development of primary neurons and astrocytes on thoroughly controlled functional groups. Negatively charged surfaces presenting carboxylate (COO^-) or sulfonate (SO₃^-) groups prove beneficial to neuronal behavior, in spite of their supposed repulsive electrostatic interactions with cellular membranes. The adhesion and survival of primary hippocampal neurons on negatively charged surfaces are comparable to or slightly better than those on positively charged (poly-d-lysine-coated) surfaces, and neuritogenesis and neurite outgrowth are accelerated on COO^- and SO₃^- surfaces. Moreover, such favorable influences of the negatively charged surfaces are only seen in neurons but not for astrocytes. Our results indicate that the in vitro developmental behavior of primary hippocampal neurons is sophisticatedly modulated by angstrom-sized differences in chemical structure or the charge density of the surface. We believe that this work provides new implications for understanding neuron-material interfaces as well as for establishing new ways to fabricate neuro-active surfaces.

Xerogel modified diatomaceous earth microparticles for controlled drug release studies

An alternative facile approach for the surface modification of naturally available diatoms with xerogel for controlled drug release applications.

Dacarbazine-Loaded Hollow Mesoporous Silica Nanoparticles Grafted with Folic Acid for Enhancing Antimetastatic Melanoma Response

Dacarbazine (DTIC) is one of the most important chemotherapeutic agents for the treatment of melanoma; however, its poor solubility, photosensitivity, instability, and serious toxicity to normal cells limit its clinical applications. In this article, we present a rationally designed nanocarrier based on hollow mesoporous silica nanoparticles (HMSNs) for the encapsulation and targeted release of DTIC for eradicating melanoma. The nanocarrier (DTIC@HMLBFs) is prepared by modifying HMSNs with carboxyl groups to enhance the loading of DTIC, followed by further enveloping of folic acid-grafted liposomes, which act as a melanoma active target for controlled and targeted drug release. In vitro, DTIC@HMLBFs exhibited the strongest cytotoxicity to melanoma cells compared with DTIC@HMSNs and free DTIC. The in vivo investigations demonstrate that the rationally designed nanocarrier loaded with DTIC achieves significant improvement against lung metastasis of melanoma via targeting melanoma cells and tumor-associated macrophages. This study provides a promising platform for the design and fabrication of multifunctional nanomedicines, which are potentially useful for the treatment of melanoma.