China
Africa
Explore chapters and articles related to this topic
Phototherapy Using Nanomaterials
Published in D. Sakthi Kumar, Aswathy Ravindran Girija, Bionanotechnology in Cancer, 2023
A. N. Resmi, V. Nair Resmi, C. R. Rekha, V. Nair Lakshmi, Shaiju S. Nazeer, Ramapurath S. Jayasree
In another work, the photosensitize MB was encapsulated into three types of nanoparticles: polyacrylamide, sol–gel silica, and organically modified silicate (ORMOSIL). On light irradiation, the entrapped MB was able to generate 1O2 and a significant amount diffused out of the matrix entered the adjacent cell membranes and destroyed tumor cells. Photocytotoxicity of these nanoparticles was evaluated on rat C6 glioma tumor cells in vitro [182]. In addition, nanoparticle based on polyacrylamide matrix provides protection for embedded MB against the reduction of diaphorase enzymes, thereby retaining the photoactive form of MB for efficient PDT treatment. It was observed that upon light irradiation, the MB-containing NP could induce photodynamic effects on rat C6 glioma cells. The encapsulated MB allows sufficient light-stimulated generation of 1O2 as well as adequate diffusion out of the matrix to cause damage to the tumor cells [183].
Nanomedicine(s) under the Microscope *
Published in Valerio Voliani, Nanomaterials and Neoplasms, 2021
Smaller luminescent porous silicon nanoparticles (LPSiNPs ∼126 nm) including an NIR probe to monitor biodistribution and degradation [349] were shown to accumulate in the liver and spleen after iv injection. They disappear within 4 weeks, and this was attributed to degradation to soluble silicic acid. PEGylationis being explored as a means of tuning the degradation rate of silicon [350, 351]. Stoddart and colleagues have taken a different approach. Their mesoporous silica nanoparticles have surface-bound rotaxanes (encircled by cucurbit[6]uril or α-cyclodextrin rings) designed for reductive or pH triggered degradation. This chemistry acts as a gateway (“nanostoppers” or “nanovalves”) for drug release [344, 351, 352], and the field of molecular/supramolecular switches is reviewed in Ref. [353]. Organically modified silica (ORMOSIL) nanoparticles (20–25 nm) conjugated with NIR fluorophores and radiolabeled with [124I] iodide for optical and PET imaging [354] also accumulated in liver and spleen thus diminishing the opportunity for tumor drug delivery or tumor imaging.
Mesoporous silica nanoparticles: synthesis methods and their therapeutic use-recent advances
Published in Journal of Drug Targeting, 2021
Mohsen Ghaferi, Maedeh Koohi Moftakhari Esfahani, Aun Raza, Sitah Al Harthi, Hasan Ebrahimi Shahmabadi, Seyed Ebrahim Alavi
The colloidal instabilities and large particle size are still the two disadvantages of MSNPs that must be addressed to improve their applications. In this regard, ORMOSIL NPs can be considered as exciting hybrid materials. These NPs can be readily synthesised at room temperature as an oil-in-water microemulsion from TEOS/vinyltriethoxysilane (VTES) and (3-aminopropyl)triethoxysilane (APTES)/mercaptopropyltrimethoxysilane (MPTMS)/diethylenetriamine (DETA) as inorganic and organic silica precursor, respectively. Also, to synthesise ORMOSIL NPs, weak alkali solutions are used as catalysts. The synthesis method of ORMOSIL NPs is feasible and time-saving as its synthesis does not depend upon surfactants and corrosive solvents.