Galactose Functionalized Mesoporous Silica Nanoparticles As Delivery Vehicle in the Treatment of Hepatitis C Infection

Silicon-containing nanomedicine and biomaterials: materials chemistry, multi-dimensional design, and biomedical application

The invention of silica-based bioactive glass in the late 1960s has sparked significant interest in exploring a wide range of silicon-containing biomaterials from the macroscale to the nanoscale. Over the past few decades, these biomaterials have been extensively explored for their potential in diverse biomedical applications, considering their remarkable bioactivity, excellent biocompatibility, facile surface functionalization, controllable synthesis, etc. However, to expedite the clinical translation and the unexpected utilization of silicon-composed nanomedicine and biomaterials, it is highly desirable to achieve a thorough comprehension of their characteristics and biological effects from an overall perspective. In this review, we provide a comprehensive discussion on the state-of-the-art progress of silicon-composed biomaterials, including their classification, characteristics, fabrication methods, and versatile biomedical applications. Additionally, we highlight the multi-dimensional design of both pure and hybrid silicon-composed nanomedicine and biomaterials and their intrinsic biological effects and interactions with biological systems. Their extensive biomedical applications span from drug delivery and bioimaging to therapeutic interventions and regenerative medicine, showcasing the significance of their rational design and fabrication to meet specific requirements and optimize their theranostic performance. Additionally, we offer insights into the future prospects and potential challenges regarding silicon-composed nanomedicine and biomaterials. By shedding light on these exciting research advances, we aspire to foster further progress in the biomedical field and drive the development of innovative silicon-composed nanomedicine and biomaterials with transformative applications in biomedicine.

Multivalent Lactobionic Acid and N-Acetylgalactosamine-Conjugated Peptide Nucleic Acids for Efficient In Vivo Targeting of Hepatocytes

Peptide nucleic acids (PNAs) are used/applied in various studies to target genomic DNA and RNA to modulate gene expression. Non-specific targeting and rapid elimination always remain a challenge for PNA-based applications. Here, the synthesis, characterization, in vitro and in vivo study of di lactobionic acid (diLBA) and tris N-acetyl galactosamine (tGalNAc) conjugated PNAs for liver-targeted delivery are reported. For proof of concept, diLBA, and tGalNAc conjugated PNAs (anti-miR-122 PNAs) were synthesized to target microRNA-122 (miR-122) which is over-expressed in the hepatic tissue. Different lengths of anti-miR-122 PNAs conjugated with diLBA and tGalNAc are tested. Cell culture and in vivo analyses to determine biodistribution, efficacy, and toxicity profile are performed. This work indicates that diLBA conjugates show significant retention in hepatocytes in addition to tGalNAc conjugates after in vivo delivery. Full-length PNA conjugates show significant downregulation of miR-122 levels and subsequent de-repression of its downstream targets with no evidence of toxicity. The results provide a robust framework for ligand-conjugated delivery systems for PNAs that can be explored for broader biomedical applications.

Enhanced adsorption and colorimetric detection of tetracycline antibiotics by using functional phosphate/carbonate composite with nanoporous network coverage

This work presents efficient tetracycline (TC) antibiotics adsorption using a functional porous phosphate/carbonate composite (PCC). The PCC was fabricated by anion-exchange of phosphate on the surface of vaterite-phase calcium carbonate particle scaffolds. The PCC, having dense nanoporous network coverage with large surface area and pore volume, exhibited excellent TC adsorption in solution. Its adsorption isotherm fitted well to the Freundlich model, with a maximum adsorption capacity of 118.72 mg/g. The adsorption process was spontaneous, endothermic, and followed pseudo-second-order kinetics. From the XPS analysis, the hydrogen bonding and surface complexation were the key interactions in the process. In addition, a colorimetric TC detection method was developed considering its complexation with phosphate ions, originating from PCC dissolution, during adsorption. The method was used to detect TC in mg/L concentrations in water samples. Thus, the multifunctional PCC exhibited potential for use in TC removal and environmental remediation.

Current status of silica-based nanoparticles as therapeutics and its potential as therapies against viruses

In the past decade, interest in nanoparticles for clinical indications has been steadily gaining traction. Most recently, Lipid Nanoparticles (LNP) have been used successfully to construct the SARS-CoV-2 mRNA vaccines for rapid pandemic response. Similarly, silica is another nanomaterial which holds much potential to create nanomedicines against pathogens of interest. One major advantage of silica-based nanoparticles is its crystalline and highly ordered structure, which can be specifically tuned to achieve the desired properties needed for clinical applications. Increasingly, clinical research has shown the potential of silica nanoparticles not only as an antiviral, but also its ability as a delivery system for antiviral small molecules and vaccines against viruses. Silica has an excellent biosafety profile and has been tested in several early phase clinical trials since 2012, demonstrating good tolerability and minimal reported side effects. In this review, we discuss the clinical development of silica nanoparticles to date and identify the gaps and potential pitfalls in its path to clinical translation.

Molecular Level Characterisation of the Surface of Carbohydrate-Functionalised Mesoporous silica Nanoparticles (MSN) as a Potential Targeted Drug Delivery System via High Resolution Magic Angle Spinning (HR-MAS) NMR Spectroscopy

Atomistic level characterisation of external surface species of mesoporous silica nanoparticles (MSN) poses a significant analytical challenge due to the inherently low content of grafted ligands. This study proposes the use of HR-MAS NMR spectroscopy for a molecular level characterisation of the external surface of carbohydrate-functionalised nanoparticles. MSN differing in size (32 nm, 106 nm, 220 nm) were synthesised using the sol-gel method. The synthesised materials displayed narrow particle size distribution (based on DLS and TEM results) and a hexagonal arrangement of the pores with a diameter of ca. 3 nm as investigated with PXRD and N₂ physisorption. The surface of the obtained nanoparticles was functionalised with galactose and lactose using reductive amination as confirmed by FTIR and NMR techniques. The functionalisation of the particles surface did not alter the pore architecture, structure or morphology of the materials as confirmed with TEM imaging. HR-MAS NMR spectroscopy was used for the first time to investigate the structure of the functionalised MSN suspended in D₂O. Furthermore, lactose was successfully attached to the silica without breaking the glycosidic bond. The results demonstrate that HR-MAS NMR can provide detailed structural information on the organic functionalities attached at the external surface of MSN within short experimental times.

NVCL-Based Galacto-Functionalized and Thermosensitive Nanogels with GNRDs for Chemo/Photothermal-Therapy

Dual-function nanogels (particle size from 98 to 224 nm) synthesized via surfactant-free emulsion polymerization (SFEP) were tested as smart carriers toward synergistic chemo- and photothermal therapy. Cisplatin (CDDP) or doxorubicin (DOX) and gold nanorods (GNRDs) were loaded into galacto-functionalized PNVCL-based nanogels, where the encapsulation efficiency for CDDP and DOX was around 64 and 52%, respectively. PNVCL-based nanogels were proven to be an efficient delivery vehicle under conditions that mimic the tumor site in vitro. The release of CDDP or DOX was slower at pH 7.4 and 37 °C than at tumor conditions of pH 6 and 40 °C. On the other hand, in the systems with GNRDs at pH 7.4 and 37 °C, the sample was irradiated with a 785 nm laser for 10 min every hour, obtaining that the release profiles were even higher than in the conditions that simulated a cancer tissue (without irradiation). Thus, the present study demonstrates the synergistic effect of chemo- and photothermal therapy as a promising dual function in the potential future use of PNVCL nanogels loaded with GNRDs and CDDP/DOX to achieve an enhanced chemo/phototherapy in vivo.

In Situ Formation of Au-Glycopolymer Nanoparticles for Surface-Enhanced Raman Scattering-Based Biosensing and Single-Cell Immunity

Successful synthesis of glyconanoparticles has attracted much attention due to their various biointeractive capabilities, but it is still a challenge to understand different single-cell responses to exogenous particles among cell populations. Herein, we designed polyaniline-containing galactosylated gold nanoparticles (Au@PGlyco NPs) via in situ polymerization of ortho-nitrophenyl-β-galactoside assisted by Au nucleation. The nanogold-carrying polyaniline block produced electromagnetic enhancement in surface-enhanced Raman scattering (SERS). The underlying polymerization mechanism of ortho-nitrophenyl compounds via the formation of Au nanoparticles was investigated. Depending on how the galactoside moiety reacted with β-galactosidase derived from bacteria, the Au@PGlyco NPs-mediated SERS biosensor could detect low amounts of bacteria (∼1 × 102 CFU/mL). In addition, a high accumulation of Au@PGlyco NPs mediated the immune response of tumor-associated M2 macrophages to the immunogenic M1 macrophage transition, which was elicited by reactive oxygen levels biostimulation using single-cell SERS-combined fluorescence imaging. Our study suggested that Au@PGlyco NPs may serve as a biosensing platform with the labeling capacity on galactose-binding receptors expressed cell and immune regulation.