Magnetic Nanoscalpel for the Effective Treatment of Ascites Tumors

Abstract

One of the promising novel methods for radical tumor resection at a single-cell level is magneto-mechanical microsurgery (MMM) with magnetic nano- or microdisks modified with cancer-recognizing molecules. A low-frequency alternating magnetic field (AMF) remotely drives and controls the procedure. Here, we present characterization and application of magnetic nanodisks (MNDs) as a surgical instrument (“smart nanoscalpel”) at a single-cell level. MNDs with a quasi-dipole three-layer structure (Au/Ni/Au) and DNA aptamer AS42 (AS42-MNDs) on the surface converted magnetic moment into mechanical and destroyed tumor cells. The effectiveness of MMM was analyzed on Ehrlich ascites carcinoma (EAC) cells in vitro and in vivo using sine and square-shaped AMF with frequencies from 1 to 50 Hz with 0.1 to 1 duty-cycle parameters. MMM with the “Nanoscalpel” in a sine-shaped 20 Hz AMF, a rectangular-shaped 10 Hz AMF, and a 0.5 duty cycle was the most effective. A sine-shaped field caused apoptosis, whereas a rectangular-shaped field caused necrosis. Four sessions of MMM with AS42-MNDs significantly reduced the number of cells in the tumor. In contrast, ascites tumors continued to grow in groups of mice and mice treated with MNDs with nonspecific oligonucleotide NO-MND. Thus, applying a “smart nanoscalpel” is practical for the microsurgery of malignant neoplasms.

Green Ultrasound-Assisted Synthesis of Surface-Decorated Nanoparticles of Fe3O4 with Au and Ag: Study of the Antifungal and Antibacterial Activity

“…In the case of the SERS methodology, it is based on an amplification of Raman scattering of the specific molecules absorbed on the metallic nanostructures or rough metal surfaces [ 16 ]. On the other hand, the magnetic materials, such as the SPION’s, the magnetic properties and functionality of these species have generated multiple applications in magnetic resonance imaging (MRI), specifically as magnetic contrast agents [ 17 ]. In this sense, new researchers are focused on developing nanostructures with iron oxide cores and some coatings or shells with hydrophilic properties with the finality to increase the magnetic susceptibility and consequently, their functionality [ 18 ].…”

“…The green synthesis of nanostructures is commonly based on the use of extracts from plants, bacteria, algae, fungi, roots, and yeasts, among others, as reducing agents during green synthesis [ 4 , 30 , 31 ]. This is due to the nanostructures containing high levels of antioxidants, phenolic compounds, flavonoids, isoflavones flavanones, flavones, flavanols, and anthocyanidins [ 17 , 18 , 19 ]. Additionally, the implementation of ultrasound-assisted green synthesis represents a great alternative for obtaining bifunctional system nanostructures composed of SPIONs, Au, and Ag [ 19 , 25 , 32 ].…”