Investigation of Inclusion States of Silicate and Carbonate Ions in Hydroxyapatite Particles Prepared under the Presence of Sodium Silicate

Biological hydroxyapatite (HA) contains the different minor ions which favour its bio-reactivity in vivo. In this study, the preparation of HA particles containing both silicate and carbonate ions under the presence of sodium silicate was investigated, and the physicochemical properties were evaluated according to the contents and states of silicate and carbonate ions. The increment in the silicate ion reduced the crystallinity and expanded the crystalline size along with a-axis. Solid-state ²⁹Si–NMR spectra indicated the increase in the adsorption of oligomeric silicate species on the HA particle surfaces in addition to the substitution state of silicate ions, suggesting the occurrence of the surface coating of silicates on the surfaces. The possible states of carbonate and silicate ions at the HA surfaces will provide the bioactivity.

Recent Advances in Nanotherapeutics for Multiple Myeloma

Simple Summary

Nanotherapeutics are useful tools to improve the deliverability of drugs, especially anti-cancer drugs that need to target specific cells. Several approaches have been studied for multiple myeloma, considering that immune cells are not easy to target with the available drugs. These pharmacological agents are administered in various combinations using Thalidomide (or Lenalidomide, Pomalidomide), corticosteroids (Dexamethasone), proteasome inhibitors (Bortezomib, Carfilzomib, Ixazomib), deacetylase inhibitors (Panobinostat), and monoclonal antibodies (Elotuzumab, Daratumumab). As all drugs these agents might have serious side effects and in addition, the reliance on stochastic events to deliver drugs to tumors reduces their effectiveness either through rapid clearance from blood or inadequate concentration in cancer cells. To address these issues liposomes, micelles, polymeric nanoparticles, inorganic nanoparticles, and carbon-based nanomaterials have been successfully tested in vivo and can be considered as useful tools to improve delivery of active pharmaceuticals that show poor bioavailability or poor internalization into myeloma cells.

Abstract

Anticancer therapies cannot be included in a one-size-fits-all scenario; it is imperative to adapt therapies to the tumor molecular profile and most importantly to develop target-specific therapeutics. Nanotherapeutics can combine molecular imaging with molecular therapy in order to provide the maximum benefit to patients in terms of disease prevention, identification, and treatment. Nanotechnology applied to therapy provides numerous advantages in diagnostics and in drug delivery, especially for those malignant cells that are difficult to target or for drugs with poor bioavailability, such as those used for multiple myeloma (MM). This review summarizes the recent advances in the development of nanoparticle-based systems for the treatment of MM, taking into account the methods used for their functionalization, biocompatibility, and anticancer activity.

Fluorophore-free luminescent double-shelled hollow mesoporous silica nanoparticles as pesticide delivery vehicles

Recently, mesoporous silica nanoparticles (MSNs) have become popular nanomaterials in smart delivery systems. Although research progress in the application of MSNs as pesticide carriers has been achieved, multifunctional MSNs endowed with bright luminescent centers facilitating the tracking of MSNs in biological systems and versatile structural properties possessing a high drug loading capacity and regulable release are still highly desirable. In the present work, we reported a fluorophore-free method to endow MSNs with stable fluorescence and a double-shelled hollow structure; they were prepared by a selective-etching strategy and subsequent annealing treatment. The strong and stable luminescence is found to originate from the carbon dots generated from the calcination. Their well-defined morphological structure was confirmed by SEM and TEM imaging. These versatile silica nanoparticles served as a novel delivery system for the pesticide pyraclostrobin with a loading content of 28.5%. The pyraclostrobin-loaded nanoparticles showed an initial burst, followed by subsequent sustained release behavior. The fungicidal activity of pyraclostrobin-loaded silica nanoparticles against the fungus Phomopsis asparagi (Sacc.) as well as their visual observation in the mycelium was explored. Furthermore, the effect of pyraclostrobin-loaded nanoparticles on the morphology and ultrastructure of the mycelium was investigated by SEM and TEM observations. This research seeks to develop a novel nanocarrier platform for the potential application of pesticides in sustainable plant protection.

Host–guest luminescent materials based on highly emissive species loaded into versatile sol–gel hosts

By mostly focusing on the findings of our group, this concise review provides insights into the development of promising new host–guest optical materials based on sol–gel assemblies of versatile hosts and highly luminescent guests.