Magnetothermally Activated Nanometer-level Modular Functional Group Grafting of Nanoparticles.

Nanoparticles with multifunctionality and high colloidal stability are essential for biomedical applications. However, their use is often hindered by the formation of thick coating shells and/or nanoparticle agglomeration. Herein, we report a single nanoparticle coating strategy to form 1 nm polymeric shells with a variety of chemical functional groups and surface charges.

Preparation of drug-immobilized anti-adhesion agent using visible light-curable alginate derivative containing furfuryl group.

This study demonstrated the anti-adhesion and wound healing effect of a visible light curable anti-adhesion agent using an alginate derivative modified with a furfuryl moiety. Visible light-curable furfuryl alginate (F-Alg) was prepared in conjugation with alginate and furfurylamine by an amide coupling reaction, and the conjugated F-Alg was characterized by H NMR analysis. The cytotoxicity, cell adhesion, and cell permeability of the F-Alg were evaluated for use in anti-adhesion applications.

Biocompatible, drug-loaded anti-adhesion barrier using visible-light curable furfuryl gelatin derivative.

Recently, many of studies have been attempted to determine how to decrease adhesion. To effectively prevent adhesion, decrease in unnecessary surgical procedures, prevention of contact with other tissue, and drug treatment for inflammation are required. However, current anti-adhesion materials have disadvantages.

Visible and UV-curable chitosan derivatives for immobilization of biomolecules.

Chitosan, which has many biocompatible properties, is used widely in medical field like wound healing, drug delivery and so on. Chitosan could be used as a biomaterial to immobilize protein-drug. There are many methods to immobilize protein-drug, but they have some drawbacks such as low efficiency and denaturation of protein.

Ultrathin Interface Regime of Core-Shell Magnetic Nanoparticles for Effective Magnetism Tailoring.

The magnetic exchange coupling interaction between hard and soft magnetic phases has been important for tailoring nanoscale magnetism, but spin interactions at the core-shell interface have not been well studied. Here, we systematically investigated a new interface phenomenon termed enhanced spin canting (ESC), which is operative when the shell thickness becomes ultrathin, a few atomic layers, and exhibits a large enhancement of magnetic coercivity (H). We found that ESC arises not from the typical hard-soft exchange coupling but rather from the large magnetic surface anisotropy (K) of the ultrathin interface.

Quantitative Measurements of Size-Dependent Magnetoelectric Coupling in FeO Nanoparticles.

Bulk magnetite (FeO), the loadstone used in magnetic compasses, has been known to exhibit magnetoelectric (ME) properties below ∼10 K; however, corresponding ME effects in FeO nanoparticles have been enigmatic. We investigate quantitatively the ME coupling of spherical FeO nanoparticles with uniform diameters (d) from 3 to 15 nm embedded in an insulating host, using a sensitive ME susceptometer. The intrinsic ME susceptibility (MES) of the FeO nanoparticles is measured, exhibiting a maximum value of ∼0.

Size-controlled construction of magnetic nanoparticle clusters using DNA-binding zinc finger protein.

Nanoparticle clusters (NPCs) have attracted significant interest owing to their unique characteristics arising from their collective individual properties. Nonetheless, the construction of NPCs in a structurally well-defined and size-controllable manner remains a challenge. Here we demonstrate a strategy to construct size-controlled NPCs using the DNA-binding zinc finger (ZnF) protein.

Magnetic nanoparticles for ultrafast mechanical control of inner ear hair cells.

We introduce cubic magnetic nanoparticles as an effective tool for precise and ultrafast control of mechanosensitive cells. The temporal resolution of our system is ∼1000 times faster than previously used magnetic switches and is comparable to the current state-of-the-art optogenetic tools. The use of a magnetism-gated switch reported here can address the key challenges of studying mechanotransduction in biological systems.

Magnetically triggered dual functional nanoparticles for resistance-free apoptotic hyperthermia.

Overcoming resistance: Heat-treated cancer cells possess a protective mechanism for resistance and survival. Resistance-free apoptosis-inducing magnetic nanoparticles (RAINs) successfully promote hyperthermic apoptosis, obstructing cell survival by triggering two functional units of heat generation and the release of geldanamycin (GM) for heat shock protein (Hsp) inhibition under an alternating magnetic field (AMF).

Correlation of expression and activity of matrix metalloproteinase-9 and -2 in human gingival cells of periodontitis patients.

Purpose: Matrix metalloproteinases (MMPs) are capable of degrading extracellular matrix, and they are inducible enzymes depending on an inflammatory environment such as periodontitis and bacterial infection in periodontal tissue. Gingival inflammation has been postulated to be correlated with the production of MMP-2 and MMP-9. The objective of this study was to quantify the expression and activity of MMP-9 and -2, and to determine the correlation between activity and expression of these MMPs in human gingival tissues with periodontitis.

Nanoscale magnetism control via surface and exchange anisotropy for optimized ferrimagnetic hysteresis.

With the aim of controlling nanoscale magnetism, we demonstrate an approach encompassing concepts of surface and exchange anisotropy while reflecting size, shape, and structural hybridization of nanoparticles. We visualize that cube has higher magnetization value than sphere with highest coercivity at 60 nm. Its hybridization into core-shell (CS) structure brings about a 14-fold increase in the coercivity with an exceptional energy conversion of magnetic field into thermal energy of 10600 W/g, the largest reported to date.

Exchange-coupled magnetic nanoparticles for efficient heat induction.

The conversion of electromagnetic energy into heat by nanoparticles has the potential to be a powerful, non-invasive technique for biotechnology applications such as drug release, disease treatment and remote control of single cell functions, but poor conversion efficiencies have hindered practical applications so far. In this Letter, we demonstrate a significant increase in the efficiency of magnetic thermal induction by nanoparticles. We take advantage of the exchange coupling between a magnetically hard core and magnetically soft shell to tune the magnetic properties of the nanoparticle and maximize the specific loss power, which is a gauge of the conversion efficiency.