Physicochemical Properties Of Nanoparticles Research Articles

Effects of Different Surface Functionalizations of Silica Nanoparticles on Mesenchymal Stem Cells.

Physicochemical properties of nanoparticles, such as particle size, surface charge, and particle shape, have a significant impact on cell activities. However, the effects of surface functionalization of nanoparticles with small chemical groups on stem cell behavior and function remain understudied. Herein, we incorporated different chemical functional groups (amino, DETA, hydroxyl, phosphate, and sulfonate with charges of +9.5, + 21.7, -14.1, -25.6, and -37.7, respectively) to the surface of inorganic silica nanoparticles. To trace their effects on mesenchymal stem cells (MSCs) of rat bone marrow, these functionalized silica nanoparticles were used to encapsulate Rhodamine B fluorophore dye. We found that surface functionalization with positively charged and short-chain chemical groups facilitates cell internalization and retention of nanoparticles in MSCs. The endocytic pathway differed among functionalized nanoparticles when tested with ion-channel inhibitors. Negatively charged nanoparticles mainly use lysosomal exocytosis to exit cells, while positively charged nanoparticles can undergo endosomal escape to avoid scavenging. The cytotoxic profiles of these functionalized silica nanoparticles are still within acceptable limits and tolerable. They exerted subtle effects on the actin cytoskeleton and migration ability. Last, phosphate-functionalized nanoparticles upregulate osteogenesis-related genes and induce osteoblast-like morphology, implying that it can direct MSCs lineage specification for bone tissue engineering. Our study provides insights into the rational design of biomaterials for effective drug delivery and regenerative medicine.

Nanoparticles for efficient drug delivery and drug resistance in glioma: New perspectives.

Gliomas are the most common primary tumors of the central nervous system, with glioblastoma multiforme (GBM) having the highest incidence, and their therapeutic efficacy depends primarily on the extent of surgical resection and the efficacy of postoperative chemotherapy. The role of the intracranial blood-brain barrier and the occurrence of the drug-resistant gene O6-methylguanine-DNA methyltransferase have greatly limited the efficacy of chemotherapeutic agents in patients with GBM and made it difficult to achieve the expected clinical response. In recent years, the rapid development of nanotechnology has brought new hope for the treatment of tumors. Nanoparticles (NPs) have shown great potential in tumor therapy due to their unique properties such as light, heat, electromagnetic effects, and passive targeting. Furthermore, NPs can effectively load chemotherapeutic drugs, significantly reduce the side effects of chemotherapeutic drugs, and improve chemotherapeutic efficacy, showing great potential in the chemotherapy of glioma. In this article, we reviewed the mechanisms of glioma drug resistance, the physicochemical properties of NPs, and recent advances in NPs in glioma chemotherapy resistance. We aimed to provide new perspectives on the clinical treatment of glioma.

Abstract 493: Unlocking solid tumors to nano-immunotherapy

Abstract Despite the remarkable efficiency of cancer immunotherapies, only a low percentage of patients achieve long-lasting clinical responses. Non-tumor cells within the tumor microenvironment (TME), including tumor vasculature and immune stromal cells, dictate therapeutic efficacy. The presence of germinal centers (GC) within the TME of cancer patients, including infiltrating T follicular helper (Tfh) cells and B cells, has been considered predictive of response to immunotherapies. We are developing nano-immunotherapies to induce immunological memory to control tumor relapse without any follow-up treatment.Nanomaterials co-incorporated tumor-associated antigens, clinically relevant toll-like receptor ligands, and regulators of tumor progression, namely the PD-L1/PD-1 expression and the secretion of TGF-β. Nanoparticle (NP) physicochemical properties were fully addressed. The immunotherapeutic potential of this nano-immunotherapy was addressed in melanoma, colorectal cancer (CRC), pancreatic cancer, and triple-negative breast cancer (TNBC) 3D models. These were created using patient-derived tumor cells, cancer-associated fibroblasts, and endothelial cells, to which paired patients' peripheral blood mononuclear cells were added to assess T-cell infiltration and tumor sprouting to identify the best nano-immunotherapy dosage/schedule. Our in vivo studies evaluated tumor volume, and animals’ survival, and characterized the tumor-infiltrating immune cells within TME, including the differentiation of Tfh cells and primary GC by flow cytometry.Our nano-immunotherapy remodeled the TME of B16F10 melanoma, MC38 CRC, 4T1 and E0771 TNBC, and KPC PDAC. Different TME subpopulations were identified as major blockers of anti-tumor immunity, and this knowledge guided the selection of combination approaches using modulators of those tumor immune evasion-related pathways (e.g., PD-L1, FAK). Our combination nano-immunotherapies tailored to address the tumor immune suppression profile found in vaccinated animals, significantly delayed tumor development, and increased disease-free survival rates. We found that the adjuvants delivered by our NP led to a ~4-fold increase in antibody production, being far more effective in generating GC responses. Thus, the effectiveness of combinational immunotherapy is at least partially related to the modulation of Tfh cells driving the formation of GC responses.Our nano-immunotherapy is a promising clinically translatable approach to defeating solid tumors. Acknowledgments: This work was supported by PTDC/BTM-SAL/4350/2021 and LCF/PR/HR22/52420016. Citation Format: Barbara Carreira, Rita C. Acúrcio, Ana I. Matos, Liane M. Moura, Ana C. Santos, Raquel Gouveia, Jéssica Cordeiro, Carina Peres, Daniela Vaskovich-Koubi, Ron Kleiner, Sabina Pozzi, Ronit Satchi-Fainaro, Helena F. Florindo. Unlocking solid tumors to nano-immunotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 493.

Deconvolving Passive and Active Targeting of Liposomes Bearing LDL Receptor Binding Peptides Using the Zebrafish Embryo Model.

Improving target versus off-target ratio in nanomedicine remains a major challenge for increasing drug bioavailability and reducing toxicity. Active targeting using ligands on nanoparticle surfaces is a key approach but has limited clinical success. A potential issue is the integration of targeting ligands also changes the physicochemical properties of nanoparticles (passive targeting). Direct studies to understand the mechanisms of active targeting and off-targeting in vivo are limited by the lack of suitable tools. Here, the biodistribution of a representative active targeting liposome is analyzed, modified with an apolipoprotein E (ApoE) peptide that binds to the low-density lipoprotein receptor (LDLR), using zebrafish embryos. The ApoE liposomes demonstrated the expected liver targeting effect but also accumulated in the kidney glomerulus. The ldlra-/- zebrafish is developed to explore the LDLR-specificity of ApoE liposomes. Interestingly, liver targeting depends on the LDLR-specific interaction, while glomerular accumulation is independent of LDLR and peptide sequence. It is found that cationic charges of peptides and the size of liposomes govern glomerular targeting. Increasing the size of ApoE liposomes can avoid this off-targeting. Taken together, the study shows the potential of the zebrafish embryo model for understanding active and passive targeting mechanisms, that can be used to optimize the design of nanoparticles.

Study on preparation of Fe₃O₄@lapatinib nanoparticles for application as a targeted drug delivery system in the treatment of breast cancer

Systems for targeted drug delivery in the treatment of cancer using nanoparticles are currently of interest to many domestic and foreign scientists. In this work, for application as a target drug delivery system in the treatment of breast cancer Fe3O4@lapatinib nanoparticles were prepared by coprecipitation of solutions of Fe2+ and Fe3+ salts in alkaline, followed by purification in a magnetic separation system. Physicochemical properties of nanoparticles were studied and determined by XRD, TEM, DLS, HPLC, VSM, AAS and zeta potential methods. The results showed that the size of Fe3O4@lapatinib nanoparticles is in the range of 10 to 40 nm, hydrodynamic diameter is 27.4 ± 0.6 nm, saturation magnetization is 39.1 ± 3.1 emu/g, Fe content is 16.35 ± 0.97 mg/ml, lapatinib content is 8.08 ± 0.06 mg/ml, and the zeta potential is -16.2 ± 1.3 mV. Thus, the obtained Fe3O4@lapatinib nanoparticles are fully suitable for targeted drug delivery in the breast cance treatment

Iron oxide nanoparticles coated with Glucose and conjugated with Safranal (Fe3O4@Glu-Safranal NPs) inducing apoptosis in liver cancer cell line (HepG2)

Magnetic nanoparticles can be considered a reliable tool for targeted drug delivery to cancer tissues. Based on this, in this study, the anticancer effect of iron oxide nanoparticles coated with glucose and conjugated with Safranal (Fe3O4@Glu-Safranal NPs) on a liver cancer cell line (HepG2) was investigated. Physicochemical properties of nanoparticles were characterized using FT-IR, XRD, VSM, EDS-mapping, SEM and TEM imaging, zeta potential, and DLS analyses. MTT test was used to investigate the inhibitory effect of nanoparticles on cancer and normal cell lines. Also, the reactive oxygen species (ROS) level, the population of apoptotic cells, and cell cycle analysis were evaluated in control and nanoparticle-treated cells. The synthesized particles were spherical, in a size range of 17–49 nm, without impurities, with a surface charge of − 13 mV and hydrodynamic size of 129 nm, and with magnetic saturation of 22.5 emu/g. The 50% inhibitory concentration (IC50) of Safranal, Fe3O4, Fe3O4@Glu-Safranal and Cisplatin drug on liver cancer cells were 474, 1546, 305 and 135 µg/mL, respectively. While, the IC50 of Fe3O4@Glu-Safranal for normal cell line was 680 µg/mL. Treating liver cancer cells with nanoparticles significantly increased the population of apoptotic cells from 2.5% to 34.7%. Furthermore, the population of the cells arrested at the G2/M phase increased in nanoparticle-treated cells. Due to the biocompatibility of the constituent compounds of these nanoparticles, their magnetic properties, and their inhibitory effects on cancer cells, Fe3O4@Glu-Safranal NPs can be further considered as a promising anticancer compound.

Uncovering the Importance of Ligand Mobility on Cellular Uptake of Nanoparticles: Insights from Experimental, Computational, and Theoretical Investigations.

The cellular uptake of nanoparticles (NPs) by biological cells is an important and fundamental process in drug delivery. Previous studies reveal that the physicochemical properties of nanoparticles as well as those of functionalized ligands can both critically affect the uptake behaviors. However, the effect of the conjugation strategy (i.e., the "bond" between the ligand and the NP) on the cellular uptake is overlooked and remains largely elusive. Here, by taking the broadly employed gold nanoparticle as an example, we comprehensively assessed the relationship between the conjugation strategy and uptake behaviors by introducing three ligands with the same functional terminal but different anchoring sites. As revealed by in vitro cell experiments and multiscale molecular simulations, the uptake efficiency of gold NPs was positively correlated with the strength of the "bond" and more specifically the ligand mobility on the NP surface. Moreover, we validated the results presented above by proposing a thermodynamic theory for the wrapping of NPs with mobile ligands. Further, we also showed that the endocytic pathway of NPs was highly dependent on ligand mobility. Overall, this study uncovered a vital role of conjugation strategy in the cellular uptake and may provide useful guidelines for tailoring the biobehaviors of nanoparticles.

Hybrid Nanoparticle for Co-delivering Paclitaxel and Dihydroartemisinin to Exhibit Synergic Anticancer Therapeutics.

Anticancer treatment is required to provide effective and safe patient medicines. This research aided in developing and applying nanoparticles (NPs) for cancer treatment. The poor solubility of paclitaxel (PTX) restricts its therapeutic efficacy because of allergic side effects caused by formulation excipients. To overcome this, PTX was coupled with artemisinin derivatives and loaded into an NP drug delivery system to enhance its effects while addressing its low solubility. This study prepared and characterized a hybrid PLGA-lecithin NP containing dihydroartemisinin (DHA) and PTX for synergic anticancer therapy. A lyophilization study improved the stability of the NP drug formulations. Dual PTX- and DHA-loaded PLGA- and lecithin-based NPs were prepared using a single-step solvent evaporation method. The NP suspensions were lyophilized, and the types and ratios of cryoprotectants were investigated. The physicochemical properties of NPs and lyophilized cakes (Lyo-NPs) were characterized. The stability of the Lyo-NPs was investigated at 2-8°C and room conditions. The anticancer effects of the drug combination, NP suspension, and lyophilized powder were analyzed using an in vitro cytotoxicity assay and an in vivo model. The optimal PTX-DHA loaded PLGA-lecithin-NP was formulated (200 nm, PDI: 0.248 ± 0.003, Zeta potential: -33.60 ± 3.39 mV). Mannitol was selected for lyophilization. Lyo-NPs improved the stability of the NPs (1 year), wherein the physicochemical properties of the NPs were maintained (RDI was close to 1.0). An in-vitro cytotoxicity assay of PTX combined with DHA showed a synergistic anticancer effect (CI <1.0). The suppressive effects of Lyo-NPs on tumor growth in vivo were dose-dependent. While the cocktail of free drugs showed high toxicity (7.5 mg PTX-15 mg DHA/kg) in-vivo, Lyo-NPs showed no statistical differences in hematological and biochemical parameters compared to the control. Dual-drug-loaded hybrid PLGA-lecithin NP is a potential system to minimize severe side effects while enhancing antitumor efficacy, in which lyophilization is a key process to increase stability.</p>.

An electrochemical aptasensor based on AuPt@PEI-g-C3N4 combined with a rolling circle amplification strategy for ultrasensitive detection of ciprofloxacin

The precise and sensitive quantification of ciprofloxacin (CIP) is imperative due to its prevalent misapplication and overutilization, which can elicit detrimental side effects. Here, an electrochemical aptasensor based on PEI-g-C3N4 compounded with gold-platinum nanoshell nanomaterials (AuPt@PEI-g-C3N4) combined with a rolling circle amplification (RCA) strategy for an ultrasensitive detection of CIP. Physicochemical properties of nanoparticles and aptamers and analytical parameters of aptasensor were determined by Fourier Transform Infrared, scanning and transmission electron microscopy, gel electrophoresis, cyclic voltammetry, and electrochemical impedance spectroscopy. Furthermore, the RCA strategy was employed to generate long G-rich sequences to load an amount of methylene blue (MB) as signal probes in a potassium ions (K+) environment for signal amplification. In the presence of CIP, the formation of the Apt-CIP complex will cause the dissociation of signal probes from gold electrodes (AuE), reducing electrochemical signals significantly. Under optimal experimental conditions, the designed aptasensor showed excellent comprehensive performance with a good linear relationship in the wide range of 1.0 × 10−4 to 1.0 × 102 ng/mL, and its detection limit was low at 1.03 × 10−5 ng/mL. The assay revealed satisfactory levels of specificity, immunity to interference, stability, and repeatability. Additionally, we successfully applied this aptasensor to spiked milk and surface water samples from Dongfeng Canal (China) for CIP detection.

Improving ruthenium nanoparticle physicochemical properties and chemotherapeutic efficacy by dual-encapsulating with new amphiphilic chitosan and imidazolium ionic liquid

This study introduces new amphiphilic low-molecular-weight chitosan (ALMC) and imidazolium ionic liquid (IIL) as encapsulating agents for in-situ ruthenium nanoparticles (RuNPs) synthesis, resulting in Ru-nanobicomposites (RNBCs: Ru/IIL, RNBC1; Ru-IIL/ALMC, RNBC2) with mean diameters of (2.16–5.19 nm). RNBCs display remarkable collodial stability with high ζ-potential values ((+39.95)–(+48.07) mV) and uniform size distribution with low polydispersity index values (0.23–0.21). In vitro experiments revealed that RNBCs had potent anti-cancer properties, with IC50 values indicating that they were more toxic to HepG2 cells (IC50 = 2.16 ± 0.17–9.12 ± 0.71 μg/ml) than CaCo-2 cells (IC50 = 0.61 ± 0.25–11.05 ± 0.48 μg/ml). Specifically, IIL and ALMC's dual-encapsulated RuNPs (RNBC2) could be a potential anticancer drug. RNBC2 increased intrinsic apoptotic markers P53 and Bax gene expression and inhibited Topo II, damaging liver cancer cells. These findings show that RuNPs' encapsulating materials affect their interactions with cancer cells and enhance their anticancer capabilities.

Preparation of PMMA-Based Temperature/pH Responsive Nanoparticles Encapsulating 5-Fluorouracil and Methotrexate In Situ by One-Pot Dispersion Photopolymerization.

In order to achieve long-term and controllable release of anti-tumor drugs at specific sites, temperature/pH responsive nanoparticles encapsulating 5-fluorouracil and methotrexate in situ are prepared through dispersion photopolymerization under green LED irradiation. The physicochemical properties of nanoparticles are characterized by scanning electron microscopy, Fourier transform infrared, dynamic light scattering, thermogravimetric/differential scanning calorimetry, and X-ray diffraction. In vitro drug release at different temperatures and pH values is examined to ascertain the release pattern of two drugs, which can be well described by Korsmeyer-Peppas kinetic model. The cytotoxicity evaluation illustrates that the tumor cells could be more effectively killed by the drug-loaded nanoparticles, and the improved therapeutic effect is attributed to the controllable and sustainable drug release as well as the enhanced cellular uptake. The blood safety and good biocompatibility of nanoparticles are further confirmed by hemolysis assay, indicating the prepared nanoparticles are potential candidates for effective tumor treatment.

Nanoparticles traversing the extracellular matrix induce biophysical perturbation of fibronectin depicted by surface chemistry.

While the filtering and accumulation effects of the extracellular matrix (ECM) on nanoparticles (NPs) have been experimentally observed, the detailed interactions between NPs and specific biomolecules within the ECM remain poorly understood and pose challenges for in vivo molecular-level investigations. Herein, we adopt molecular dynamics simulations to elucidate the impacts of methyl-, hydroxy-, amine-, and carboxyl-modified gold NPs on the cell-binding domains of fibronectin (Fn), an indispensable component of the ECM for cell attachment and signaling. Simulation results show that NPs can specifically bind to distinct Fn domains, and the strength of these interactions depends on the physicochemical properties of NPs. NP-NH3+ exhibits the highest affinity to domains rich in acidic residues, leading to strong electrostatic interactions that induce severe deformation, potentially disrupting the normal functioning of Fn. NP-CH3 and NP-COO- selectively occupy the RGD/PHSRN motifs, which may hinder their recognition by integrins on the cell surface. Additionally, NPs can disrupt the dimerization of Fn through competing for residues at the dimer interface or by diminishing the shape complementarity between dimerized proteins. The mechanical stretching of Fn, crucial for ECM fibrillogenesis, is suppressed by NPs due to their local rigidifying effect. These results provide valuable molecular-level insights into the impacts of various NPs on the ECM, holding significant implications for advancing nanomedicine and nanosafety evaluation.

Antigen-Specific Stimulation of CD8+ T Cells by Murine Bone Marrow-Derived Dendritic Cells After Treatment with Nanoparticles.

The assessment of antigen presentation by dendritic cells and subsequent antigen-dependent activation of T lymphocytes is a critical step underlying the efficacy of nanoparticle-based therapeutic vaccines. Since nanoparticle physicochemical properties determine their interactions with the immune system, the early stages of nanotechnology-based vaccine development commonly involve optimizing the particles' properties to create a formulation with desired stability, antigen release, targeting of desired cell populations, and efficacy. To accelerate this process, in vitro models suitable for the rapid assessment of a novel vaccine candidate's efficacy are highly desirable. One such model is described in this protocol. Herein, nanoparticles are formulated to deliver a model antigen, SIINFEKL (OVA257-264), the immunodominant class I peptide derived from ovalbumin. These nanoparticles are added to the culture of murine bone marrow-derived dendritic cells, which are subsequently co-incubated with CD8+ T cells from OT-I transgenic mice. The efficient antigen presentation by dendritic cells results in the antigen-dependent proliferation of CD8+ T cells, which is detected by flow cytometry.

GAD plasma-assisted synthesis of ZnO nanoparticles and their photocatalytic activity

In this study we present an efficient method for synthesizing highly pure ZnO nanoparticles using a Gliding Arc Discharge (GAD) plasma system as a non-thermal plasma source. This approach offers distinct advantages over conventional techniques, including simplicity, a short synthesis time, utilization of readily available air as the source gas, and potential scalability, rendering it a promising alternative for sustainable ZnO nanoparticle production. The synthesized nanoparticles physicochemical properties were characterized using various techniques, such as scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDAX), UV-visible spectroscopy (UV–vis), Fourier-transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), Thermogravimetric Analysis (TGA), and Differential Scanning Calorimetry (DSC). Furthermore, we evaluated the effectiveness of the synthesized ZnO nanoparticles for wastewater treatment by assessing their photocatalytic activity against methylene blue (MB), Brilliant Cresyl Blue (BCB), and Congo Red (CR) under UV light irradiation for 2 h and 30 min. The results confirmed the successful synthesis of highly pure ZnO nano-powder with an average size of 27.18 nm and a band gap energy of 3.28 eV in an exceptionally brief duration and through straightforward steps. Additionally, GAD plasma-assisted ZnO nanoparticles exhibited a significant dye removal rate, showcasing their potential as highly effective materials for photocatalytic wastewater treatment. This study contributes new insights into the application of GAD plasma for nanoparticle synthesis.

Collagen-Hydroxyapatite Scaffold Platform Incorporating Dimethyloxalylglycine Loaded Polymersomes Decorated with BMP-2 Peptide for Bone Tissue Engineering

Introduction: Recent advances in the field of nanotechnology have led to the development of platforms for healing or repairing damaged tissues. The present study aimed to provide a bone extracellular matrix (ECM) mimetic platform made of hydroxyapatite and collagen loaded with nanopolymersomes encapsulating dimethyloxalylglycine (DMOG) and decorated with BMP-2 peptide in order to accelerate and increase the differentiation of mesenchymal stem cells to bone tissue. Method: In this study, polymersome nanoparticles carrying DMOG and targeted with BMP-2 peptide were prepared. The physicochemical properties of nanoparticles were evaluated. Thereafter, it was loaded into collagen-nanohydroxyapatite scaffolds and the expression levels of osteogenic genes OCN and OPN and angiogenic genes vcam, vwf, and kdr were checked in mesenchymal stem cells. Results: The surface charge and particle size of the synthesized nanoparticles were reported as -6 mv and 141 nm, respectively. The nanoparticles were able to slowly release 35% of the loaded DMOG within 30 days. The results demonstrated that the expression levels of OCN and OPN genes in cells exposed to polymersomes targeted with BMP-2 peptide were 27 and 2 times more than those of non-targeted polymersomes, respectively. In addition, the expression of angiogenic genes, vwf, kdr, and vcam, displayed a significant increase in targeted polymersomes compared to the non-targeted types (11.7-, 12.8-, and 2.17-fold, respectively). Conclusion: It seems that providing an environment similar to the bone ECM by combining an osteomimetic scaffold made of collagen-nanohydroxyapatite, DMOG as an angiogenic factor, and BMP-2 as the osteogenic factor can be effective in accelerating and increasing the differentiation of mesenchymal stem cells into osteoblasts.

Direct Assembly of Metal‐Phenolic Network Nanoparticles for Biomedical Applications

AbstractCoordination assembly offers a versatile means to developing advanced materials for various applications. However, current strategies for assembling metal‐organic networks into nanoparticles (NPs) often face challenges such as the use of toxic organic solvents, cytotoxicity because of synthetic organic ligands, and complex synthesis procedures. Herein, we directly assemble metal‐organic networks into NPs using metal ions and polyphenols (i.e., metal‐phenolic networks (MPNs)) in aqueous solutions without templating or seeding agents. We demonstrate the role of buffers (e.g., phosphate buffer) in governing NP formation and the engineering of the NP physicochemical properties (e.g., tunable sizes from 50 to 270 nm) by altering the assembly conditions. A library of MPN NPs is prepared using natural polyphenols and various metal ions. Diverse functional cargos, including anticancer drugs and proteins with different molecular weights and isoelectric points, are readily loaded within the NPs for various applications (e.g., biocatalysis, therapeutic delivery) by direct mixing, without surface modification, owing to the strong affinity of polyphenols to various guest molecules. This study provides insights into the assembly mechanism of metal‐organic complexes into NPs and offers a simple strategy to engineer nanosized materials with desired properties for diverse biotechnological applications.

Direct Assembly of Metal-Phenolic Network Nanoparticles for Biomedical Applications.

Coordination assembly offers a versatile means to developing advanced materials for various applications. However, current strategies for assembling metal-organic networks into nanoparticles (NPs) often face challenges such as the use of toxic organic solvents, cytotoxicity because of synthetic organic ligands, and complex synthesis procedures. Herein, we directly assemble metal-organic networks into NPs using metal ions and polyphenols (i.e., metal-phenolic networks (MPNs)) in aqueous solutions without templating or seeding agents. We demonstrate the role of buffers (e.g., phosphate buffer) in governing NP formation and the engineering of the NP physicochemical properties (e.g., tunable sizes from 50 to 270 nm) by altering the assembly conditions. A library of MPN NPs is prepared using natural polyphenols and various metal ions. Diverse functional cargos, including anticancer drugs and proteins with different molecular weights and isoelectric points, are readily loaded within the NPs for various applications (e.g., biocatalysis, therapeutic delivery) by direct mixing, without surface modification, owing to the strong affinity of polyphenols to various guest molecules. This study provides insights into the assembly mechanism of metal-organic complexes into NPs and offers a simple strategy to engineer nanosized materials with desired properties for diverse biotechnological applications.

Preparation of the Chitosan/Poly-γ-Glutamic Acid/Glabrid in Hybrid Nanoparticles and Study on its Releasing Property.

The aim of this study was to encapsulate glabridin (GB) into nanoparticles, prepared by an ionic-gelation method blended with chitosan (CS) and poly-γ-glutamic acid (γ-PGA) to address the issue of poor stability and low water solubility of glabridin. The physicochemical properties of nanoparticles were investigated by transmission electron microscope (TEM), dynamic light scattering (DLS) and fourier-transform infrared (FT-IR) spectroscopy. FT-IR results indicated that the spontaneous interaction between CS, γ-PGA and GB can form a cross linked network-structure, leading to the spontaneous formation of nanoparticles. Morphology of the complex particles was nano-scale spherical shape. Furthermore, particle size was decreased according to the decrease of γ-PGA contents and CS, accompanying with the increase of mixed solution transmittance. The mγ-PGA : mGB = 1: 1 and mCS: (mγ-PGA + mGB) =1: 1 were considered to be a proper preparation condition of CS/γ-PGA/GB hybrid nanoparticles, which produced the smaller nanoparticles with the satisfactory encapsulation efficiency (EE), loading content (LC) and sustained GB release. With the increase of pH values, the potential, EE, and LC decreased gradually, while the particle size increased. The nanoparticles prepared with higher molecular weight γ-PGA had larger particle size and less loading capacity on GB. Additionally, moderate weight ratio of CS/γ-PGA/GB, low pH, and high molecular weight of γ-PGA were favorable for sustained release. It can be concluded that the physicochemical properties of nanoparticles and GB release behaviors were affected by several factors including the weight ratio of CS/γ-PGA/GB, pHvalues, and γ-PGA molecular weight (MW). Nanoencapsulation using CS, γ-PGA and GB has a potential application for the development of functional cosmetic products with skin-whitening effect.

Unraveling the Adsorption Behavior of Thymol on Carbon and Silica Nanospheres for Prolonged Antibacterial Activity: Experimental and DFT Studies.

Functionalization of thymol (Thy) on nanocarriers is a key step in achieving prolonged antimicrobial activity. This requires nanomaterials with uniform particle diameters and suitable thymol sorption. Herein, hollow carbon (HC) and SiO2-carbon core-shell (SiO2@C) were investigated due to their diverse morphologies and ease of surface modification. HC (14 ± 1 nm size) and SiO2@C (10 ± 1.5 nm size) were synthesized by the Stöber method before thymol was loaded by incipient wetness impregnation. Nanoparticle physicochemical properties were characterized by advanced techniques, including X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS). Adsorption energies of thymol on the carbon and SiO2 surfaces were elucidated by density functional theory (DFT) simulations. Moreover, the in vitro thymol release profiles and antibacterial activity were evaluated. The experimental results indicated that the oxy-carbon surface species of HC led to longer thymol release profiles than the -OH group of SiO2@C. The DFT calculations revealed that the weaker physical interaction of thymol on HC was better for drug release than that on SiO2@C. Thus, a longer thymol release profile of HC with hollow structures showed better antibacterial performance against Gram-positive bacteria Staphylococcus aureus than that of SiO2@C with core-shell structures. This work confirms the important role of carbon morphology and specific functional groups in thymol release profiles for the further development of inhibition products.

Interpretable XGBoost-SHAP Model Predicts Nanoparticles Delivery Efficiency Based on Tumor Genomic Mutations and Nanoparticle Properties.

Understanding the complex interaction between nanoparticles (NPs) and tumors in vivo and how it dominates the delivery efficiency of NPs is critical for the translation of nanomedicine. Herein, we proposed an interpretable XGBoost-SHAP model by integrating the information on NPs physicochemical properties and tumor genomic profile to predict the delivery efficiency. The correlation coefficients were 0.66, 0.75, and 0.54 for the prediction of maximum delivery efficiency, delivery efficiency at 24 and 168 h postinjection for test sets. The analysis of the feature importance revealed that the tumor genomic mutations and their interaction with NPs properties played important roles in the delivery of NPs. The biological pathways of the NP-delivery-related genes were further explored through gene ontology enrichment analysis. Our work provides a pipeline to predict and explain the delivery efficiency of NPs to heterogeneous tumors and highlights the power of simultaneously using omics data and interpretable machine learning algorithms for discovering interactions between NPs and individual tumors, which is important for the development of personalized precision nanomedicine.