Cytotoxicity of Calcium Rectorite Micro/Nanoparticles before and after Organic Modification

Emerging chitin nanogels/rectorite nanocomposites for safe and effective hemorrhage control

Excessive bleeding due to trauma, surgery and diseases may cause severe mortalities. Here, an emerging chitin nanogel/rectorite nanocomposite is developed for effective hemorrhage control. Chitin chains are intercalated into rectorite and subsequent mechanical high speed stirring generates chitin nanogels, which assemble on the surface of the rectorite nanoplates through electrostatic interactions to form a sandwich structure. The in vitro experiments reveal that the nanocomposite exhibits favorable biocompatibility and negligible hemolysis (<3.5%) as compared to rectorite (40%). The nanocomposite stops bleeding in 121 s in rat tail incision and exhibits higher hemostatic activity in the rabbit artery injury model as compared to a commercialized chitosan hemostat, Celox. The efficient blood clotting activity is attributed to the induction of a coagulation cascade by rectorite and the quick adsorption and aggregation of platelets and red blood cells by chitin. The enhanced biocompatibility and hemostatic activity of the chitin/rectorite nanocomposite make it a safe and cost effective hemostat to control bleeding.

Enhanced tumor targeting effects of a novel paclitaxel-loaded polymer: PEG-PCCL-modified magnetic iron oxide nanoparticles

BACKGROUND

Multifunctional magnetic nanoparticles (MNP) have been newly developed for tumor-targeted drug carriers. To address challenges including biocompatibility, stability, nontoxicity, and targeting efficiency, here we report the novel drug deliverer poly(ethylene glycol) carboxyl-poly(ɛ-caprolactone) modified MNP (PEG-PCCL-MNP) suitable for magnetic targeting based on our previous studies.

METHODS

Their in vitro characterization and cytotoxicity assessments, in vivo cytotoxicity assessments, and antitumor efficacy study were elaborately investigated.

RESULTS

The size of PEG-PCCL-MNP was 79.6 ± 0.945 nm. PEG-PCCL-MNP showed little in vitro or in vivo cytotoxicity and good biocompatibility, as well as effective tumor-specific cell targeting for drug delivery with the presence of external magnetic field.

DISCUSSION

PEG-PCCL-MNP is a potential candidate of biocompatible and tumor-specific targeting drug vehicle for hydrophobic drugs.

Influence of Nanotoxicity on Human Health and Environment: The Alternative Strategies

Currently, nanotechnology revolutionizing both scientific and industrial community due to their applications in the fields of medicine, environmental protection, energy, and space exploration. Despite of the evident benefits of nanoparticles, there are still open questions about the influence of these nanoparticles on human health and environment. This is one of the critical issues that have to be addressed in the near future, before massive production of nanomaterials. Manufactured nanoparticles, which are finding ever-increasing applications in industry and consumer products fall into the category of emerging contaminants with ecological and toxicological effects on populations, communities and ecosystems. The existing experimental knowledge gave evidence that inhaled nanoparticles are less efficiently separated than larger particles by the macrophage clearance mechanisms and these nanoparticles are known to translocate through the lymphatic, circulatory and nervous systems to many tissues and organs, including the brain. In this review we highlight adverse impacts of nanoparticles on human and the environment with special emphasis on green nanoscience as a sustainable alternative.

Presence of nano-sized chitosan-layered silicate composites protects against toxicity induced by lead ions

Protecting cells from toxicosis even apoptosis induced by a variety of toxic heavy metals stimulus has drawn more and more attentions. This study was designed to elucidate whether chitosan-organic rectorite (CS-OREC) composites exhibited any protective effects on altered oxidative stress parameter in PC12 cells exposed to lead ions (Pb²⁺). The cells were exposed to Pb²⁺ either alone or in combination with CS-OREC composites for designated time to evaluate the efficacy of the composites on Pb²⁺-induced toxicity. The MTT assay results showed that the cell viability of PC12 was remarkably decreased when exposed to Pb²⁺, but significantly retained after adding CS-OREC composites compared to that of the control. The beneficial effect of CS-OREC composites on cytotoxicity was related, at least in part, to its ability to protect against apoptosis in PC12 cells exposed to 50μM Pb²⁺. Their protective effect was also associated with the inhibitory effect on Pb²⁺-induced activation of Bax/Bcl-2, P-38, and caspase-3 pathways, while was independent on JNK pathway.