pH Environment Research Articles

Achieving Room‐Temperature Phosphorescence in Solution Phase from Carbon Dots Confined in Nanocrystals

Carbon dots (CDs) have attracted growing interest in the construction of room‐temperature phosphorescent (RTP) materials. However, in the solution phase of CDs, it is still challenging to obtain efficient and stable phosphorescent emission due to the intense quenching effect by dissolved oxygen and solvent molecules. Herein, we report robust phosphorescence in the solution phase, achieved by encapsulating citrate‐derived CDs into NaYF4 nanocrystals via a one‐step method of high‐temperature coprecipitation. Combined characterizations show that the triplet emission from CDs is related to the abundance of C=O in the CDs, the formation of ionic‐bond networks around the CDs, and the spatial confinement and quenching inhibition effects of NaYF4 nanocrystals. Notably, the transition of CDs@NaYF4 from hydrophobicity to hydrophilicity can be easily achieved by simple surface modulation of NaYF4 nanocrystals, which allows the RTP of CDs to be maintained in either polar or nonpolar solvents. In addition, CDs@NaYF4 exhibits stable afterglow in different pH environments, suggesting its excellent stability. Finally, we demonstrated the application of CDs@NaYF4 in 3D printing, oily anti‐counterfeiting patterns, and cell imaging. Our work can serve the controllable preparation of solution‐phase RTP materials and their various applications.

Achieving Room-Temperature Phosphorescence in Solution Phase from Carbon Dots Confined in Nanocrystals.

Carbon dots (CDs) have attracted growing interest in the construction of room-temperature phosphorescent (RTP) materials. However, in the solution phase of CDs, it is still challenging to obtain efficient and stable phosphorescent emission due to the intense quenching effect by dissolved oxygen and solvent molecules. Herein, we report robust phosphorescence in the solution phase, achieved by encapsulating citrate-derived CDs into NaYF4 nanocrystals via a one-step method of high-temperature coprecipitation. Combined characterizations show that the triplet emission from CDs is related to the abundance of C=O in the CDs, the formation of ionic-bond networks around the CDs, and the spatial confinement and quenching inhibition effects of NaYF4 nanocrystals. Notably, the transition of CDs@NaYF4 from hydrophobicity to hydrophilicity can be easily achieved by simple surface modulation of NaYF4 nanocrystals, which allows the RTP of CDs to be maintained in either polar or nonpolar solvents. In addition, CDs@NaYF4 exhibits stable afterglow in different pH environments, suggesting its excellent stability. Finally, we demonstrated the application of CDs@NaYF4 in 3D printing, oily anti-counterfeiting patterns, and cell imaging. Our work can serve the controllable preparation of solution-phase RTP materials and their various applications.

Effect of ocean acidification on the oxygen consumption of the sea urchins Paracentrotus lividus (Lamarck, 1816) and Arbacia lixula (Linnaeus, 1758) living in CO2 natural gradients

Ocean acidification (OA) stands out as one of the main threats to marine ecosystems. OA leads to a reduction in the availability of carbonate ions, which are essential for marine calcifiers such as echinoderms. We aim to understand the physiological responses of two sea urchin species, Paracentrotus lividus and Arbacia lixula to low pH conditions and determine whether their responses result from phenotypic plasticity or local adaptation. The study is divided into two parts: plasticity response over time, measuring respiration rates of individuals from the Mediterranean Sea exposed to low pH over seven days, and adaptation and plasticity under changing pH, analyzing individuals inhabiting a pH gradient in a natural CO2 vent system located in La Palma Island, Spain. Over the seven days of low pH exposure, distinct patterns in respiration rates were revealed, with both species demonstrating potential for acclimatization. Notably, P. lividus and A. lixula displayed unsynchronized acidosis/alkalosis cycles, suggesting different physiological mechanisms. Additionally, environmental history seemed to influence adaptive capacity, as specimens from fluctuating pH environments exhibited respiration rates similar to those from stable environments with heightened phenotypic plasticity. Overall, our results suggest that both species possess the capacity for metabolic plasticity, which may enhance their resilience to future OA scenarios but likely involve energetic costs. Moreover, CO2 vent systems may serve as OA refugia, facilitating long-term survival. Understanding the plastic responses versus adaptations is crucial for predicting the effects of OA on species distribution and abundance of marine organisms in response to ongoing climate change.

Comammox Nitrospira act as key bacteria in weakly acidic soil via potential cobalamin sharing

AbstractThe discovery of comammox Nitrospira in low pH environments has reshaped the ammonia oxidation process in acidic settings, providing a plausible explanation for the higher nitrification rates observed in weakly acidic soils. However, the response of comammox Nitrospira to varying pH levels and its ecological role in these environments remains unclear. Here, a survey across soils with varying pH values (ranging from 4.4 to 9.7) was conducted to assess how comammox Nitrospira perform under different pH conditions. Results showed that comammox Nitrospira dominate ammonia oxidation in weakly acidic soils, functioning as a K‐strategy species characterized by slow growth and stress tolerance. As a key species in this environment, comammox Nitrospira may promote bacterial cooperation under low pH conditions. Genomic evidence suggested that cobalamin sharing is a potential mechanism, as comammox Nitrospira uniquely encode a metabolic pathway that compensates for cobalamin imbalance in weakly acidic soils, where 86.8% of metagenome‐assembled genomes (MAGs) encode cobalamin‐dependent genes. Additionally, we used DNA stable‐isotope probing (DNA‐SIP) to demonstrate its response to pH fluctuations to reflect how it responds to the decrease in pH. Results confirmed that comammox Nitrospira became dominant ammonia oxidizers in the soil after the decrease in pH. We suggested that comammox Nitrospira will become increasingly important in global soils, under the trend of soil acidification. Overall, our work provides insights that how comammox Nitrospira perform in weakly acidic soil and its response to pH changes.

Development and Evaluation of Gelatin-Based Gummy Jellies Enriched with Oregano Oil: Impact on Functional Properties and Controlled Release

Functional foods play a crucial role in contemporary dietary strategies. This study investigates the incorporation of oregano oil, a bioactive extract that is known for its antimicrobial and antioxidant properties, into gelatin-based gummy jellies to develop functional food products with controlled release properties. The jellies were evaluated for mass uniformity, swelling index, disintegration time, and tensile strength under simulated oral and gastric conditions. The results showed that oregano oil significantly reduced the swelling index (e.g., 128.76 ± 0.67% at pH 5) and prolonged the disintegration time (e.g., 6–18 min across pH environments), highlighting its potential for controlled release. The mechanical strength remained stable (5.2 ± 0.3 N), ensuring structural integrity. These findings suggest that oregano-oil-enriched gummy jellies offer health benefits, although further studies are needed to explore their long-term stability and bioavailability.

Development and characterization of hydrogel beads with carboxymethyl chitosan/graphene quantum dots@Pectin/MIL-88 for targeted doxorubicin delivery: An adaptable nanocomposite approach.

Hydrogels are adaptable substances with a 3D framework able to hold large quantities of water, which is why they are ideal for use in the field of biomedicine. This research project focused on creating a new hydrogel combining carboxymethyl chitosan (CMCS), graphene quantum dots (GQDs), pectin (Pe), and MIL-88 for precise and controlled release of the cancer drug doxorubicin (DOX). The creation of CMCS/GQDs@Pe/MIL-88 hydrogel beads was achieved through an eco-friendly one-step synthesis method. The hydrogel beads were then analyzed using various techniques including FE-SEM, EDX, FT-IR, XRD, BET surface area, DLS, and zeta potential measurements. The hydrogel beads showed great swelling ability and controlled breakdown in different pH environments, mimicking the conditions of the gastrointestinal tract and body. Research on drug loading and release showed that the hydrogel components can be adjusted to control the release of DOX. Cytotoxicity tests in a lab setting using K562 cells demonstrated successful delivery of DOX and the ability to target cancer cells specifically while reducing negative effects. Adding GQDs improved both the imaging abilities and the stability and mechanical characteristics of the hydrogel. This research indicates that the CMCS/GQDs@Pe/MIL-88 combination hydrogel beads show great potential for advanced drug delivery systems, especially in cancer treatment.

The Resistance Abilities of Some Bacillus Species to Gastrointestinal Tract Conditions: Whole Genome Sequencing of the Novel Candidate Probiotic Strains Bacillus clausiiBA8 and Bacillus subtilisBA11.

This study aims to investigate the resistance of potential probiotic Bacillus species to various conditions in the gastrointestinal (GI) tract and their safety characteristics. MALDI-TOF MS identified all tested strains with a good safety score of ≥ 2.0; the strains demonstrated the capacity to pass through the Gl tract, exhibiting a reduction of > 6 log/CFU live cells. Furthermore, they exhibited varying survival rates in an acidic environment (pH 2.0-3.0) and the presence of Ox-Bile (1% w/v) (p < 0.05). Following exposure to pH 3.0 and Ox-Bile, the survival rate of Bacillus spp. ranged between 85.94% and 91.24% and 87.30% and 91.54%, respectively. The results of the invitro experiments showed that the six Bacillus strains had comparable characteristics (e.g., tolerance to GI track enzyme, auto-aggregation ability) to the reference probiotic strain Lactiplantibacillus plantarum LA15. The auto-aggregation results of the B. clausii BA8 strain, which has demonstrated resistance to GI tract conditions, were also noteworthy. This strain showed 72.32% after 2 h and 74.55% at the end of 5 h. Most suitable for use as probiotic strains B. clausii BA8 and B. subtilis BA11, sequenced via Illumina NovaSeq, showed average nucleotide identity (ANI) values of 98.1% and 97.8%, respectively. The genome annotation of B. clausii and B. subtilis with Prokka revealed 4,498,248-4,215,606 bp genome length, 44%-43% GC content, and 110-26 contigs, respectively. B. clausii BA8 has been comprehensively characterized, is of low risk for human consumption, and has been recommended as a potential probiotic strain. However, further invivo experimentation is required to confirm these findings.

Development of an amorphous octenyl succinate anhydride starch-based emulsion to improve the stability and bioaccessibility of phloretin.

Phloretin (PHT) is a natural functional compound with antioxidant properties. However, its poor water solubility and high sensitivity to extreme pH environments, oxygen, and high temperatures limit its absorption and stability. Therefore, in this study, amorphous octenyl succinic anhydride starch (AOS) was employed to enhance the stability of PHT-loaded emulsions, and characteristics of these emulsions were evaluated. In total, three AOS samples with varying degrees of amorphous were prepared as emulsifiers. Notably, amorphous starch prepared at 90°C was found to stabilize the emulsion by forming a superior gel network structure, facilitating the efficient loading of PHT and protecting this compound from degradation in extreme environments. Finally, in vitro digestion and release experiments confirmed the effectiveness of these emulsions in PHT delivery. Compared to the existing β-cyclodextrin-PHT drug delivery system, the prepared emulsion exhibited superior PHT release at the site of intestinal absorption. Therefore, the emulsions established in this study show promise as PHT delivery systems for future applications in the food industry.

Biotechnological uses of purified and characterized alkaline cellulase from extremophilic Bacillus pumilus VLC7 from Lake Van

The present study focuses on the isolation and characterization of a bacterium from Lake Van adapted to an alkaline pH environment with significant cellulase production potential. The identified isolate, Bacillus pumilus VLC7 (GenBank Acc No: OR415888.1), exhibited the highest cellulase activity among other alkaliphilic isolates. The purification employing protein precipitation by ammonium sulfate, ultrafiltration, and ion exchange chromatography resulted in 20-fold purification with a specific activity of 16 U/mg protein. Cellulase had a molecular weight of 76 kDa, 3.13 mM Km and 0.160 U/mg Vmax values. The enzyme displayed maximum activity at pH 9.0 and 40 °C and retained at least 80% of its activity at temperatures of 25–60 °C for 90 min and pH 4–12 for one hour. Stability tests also revealed the enzyme’s resilience to various reagents, metal ions, organic solvents, and detergents. Furthermore, the biotechnological applications of cellulase were explored, demonstrating its effectiveness in fabric biopolishing (removing pilling), as well as in the removal of fabric dyes. The research findings underscore the potential of B. pumilus VLC7 as a valuable source for eco-friendly industrial biotechnology applications.Graphical

Combining SNAC and C10 in oral tablet formulations for gastric peptide delivery: A preclinical and clinical study.

Current oral formulations of macromolecules including peptides typically rely on single permeation enhancer (PE) to promote absorption and thus bioavailability. In this work, we combined two PEs, namely sodium N-[8-(2-hydroxybenzoyl) amino] caprylate (SNAC) and sodium caprate (C10), in one tablet formulation to potentially gain a synergistic effect for enhanced gastric absorption of a GLP-1 analogue and a PCSK9 inhibitor. Permeability tests on a gastric organoids-based cell model showed that the combination of SNAC and C10 can significantly improve peptide permeability compared to either SNAC or C10 alone. Tablet formulations were then designed, adjusting the total PE amount, relative ratio between SNAC and C10, and the peptide dose. To facilitate drug and PE release, a diluent was added. Upon oral administration in beagle dogs, the lead formulations made of SNAC/C10/diluent demonstrated higher bioavailability than either SNAC, SNAC/diluent and C10/diluent formulations for both peptides. Finally, the SNAC/C10/diluent formulation with PCSK9 inhibitor was tested in human, where it displayed similar bioavailability to the SNAC/diluent reference, thereby suggesting a low translatability between pre-clinical and clinical data when C10 was involved. This may be attributed to the difference in physiology, gastric pH environment as well as C10 concentration and colloidal form in the gastric lumen between dogs and humans. Hence, additional studies are needed for a better understanding of the clinical translation of C10-based peptide formulations.

U(VI) removal by zerovalent manganese modified corn straw biochar in acidic wastewater: Efficiency, characteristics and mechanism.

The chemical and radiological toxicity of uranium can present a significant risk to both human health and environmental safety. Thus, ZVMn-BC was synthesized through borohydride reduction aimed at investigating its performance in removing U(VI) in acidic environment (pH=3). Several batch experiments were conducted to assess the sorption capability under various operational conditions and the relevant experimental data were investigated by kinetics, isotherms and thermodynamic equations. ZVMn-BC exhibited excellent resistance to interference and showed a superiority on U(VI) removal over zerovalent manganese (ZVMn) and corn straw biochar (BC). Under condition of pH 3, and ambient temperature of 303K with 0.4g/L of adsorbent, ZVMn-BC exhibited a theoretical sorption quantity of 274.78mg/g. The sorption process was spontaneous and endothermic, primarily relying on chemical adsorption. The interaction mechanism involved electrostatic interaction, hydrolysis precipitation, complexation, and redox reactions. This study verified that ZVMn-BC exhibits effective performance for U(VI) eliminating in acidic wastewater.

Near-neutral pH sensing by azoheteroarene dyes.

We serendipitously discovered a novel series of azoheteroarene dyes capable of detecting pH variations in near-neutral solutions. These dyes feature thiazole, thiadiazole, triazole, pyrazole, or benzothiazole heteroaryls linked to hydroxyphenyl azo groups. They exhibit distinctive light absorption properties in aqueous solutions and show notable color changes in a narrow pH range, visible to the naked eye. Both experimental data and quantum calculations suggest a plausible mechanism for their function as pH indicators. Additionally, these azoheteroarene dyes effectively monitor pH in complex environments, and we show their use for detecting the pH change of culture medium containing growing cancer cells.

Duodenogastric Reflux in Health and Disease: Insights from a Computational Fluid Dynamics Model of the Stomach.

The stomach is responsible for physically and chemically processing the ingested meal before controlled emptying into the duodenum through the pyloric sphincter. An incompetent pylorus allows reflux from the duodenum back into the stomach, and if the amount of reflux is large enough, it could alter the low pH environment of the stomach and erode the mucosal lining of the lumen. In some cases, the regurgitated contents can also reach the esophagus leading to additional complications. In this work, "StomachSim", an in-silico model of the fluid dynamics of the stomach, is used to study the mechanism of duodenogastric reflux. The effects of variations in food properties and motility disorders on reflux are investigated. The simulations show that the primary driver of reflux is the relaxation of the antrum after a stomach contraction terminates near the pylorus. The region of the stomach walls exposed to the regurgitated contents depends significantly on the density of the stomach contents. For stomach contents of higher viscosity, the increased pressure required to maintain gastric emptying reduces the amount of duodenogastric reflux. Concomitant stomach motility disorders that weaken the relaxation of the walls also affect the amount of reflux. The study illustrates the utility of in-silico models in analyzing the factors at play in gastrointestinal diseases.

Liquid-based encapsulation for implantable bioelectronics across broad pH environments

Wearable and implantable bioelectronics that can interface for extended periods with highly mobile organs and tissues across a broad pH range would be useful for various applications in basic biomedical research and clinical medicine. The encapsulation of these systems, however, presents a major challenge, as such devices require superior barrier performance against water and ion penetration in challenging pH environments while also maintaining flexibility and stretchability to match the physical properties of the surrounding tissue. Current encapsulation materials are often limited to near-neutral pH conditions, restricting their application range. In this work, we report a liquid-based encapsulation approach for bioelectronics under extreme pH environments. This approach achieves high optical transparency, stretchability, and mechanical durability. When applied to implantable wireless optoelectronic devices, our encapsulation method demonstrates outstanding water resistance in vitro, ranging from extremely acidic environments (pH = 1.5 and 4.5) to alkaline conditions (pH = 9). We also demonstrate the in vivo biocompatibility of our encapsulation approach and show that encapsulated wireless optoelectronics maintain robust operation throughout 3 months of implantation in freely moving mice. These results indicate that our encapsulation strategy has the potential to protect implantable bioelectronic devices in a wide range of research and clinical applications.

Unraveling dolomite dissolution stoichiometry in circumneutral to alkaline pH environments

Abstract Examining carbonate dissolution kinetics at mineral-water interface is crucial to understand numerous environmental and geochemical processes, including global carbon cycling, CO2 sequestration in deep geological reservoirs, and trace elements release in terrestrial and aquatic environments. Here we explored the effect of circumneutral to alkaline pH solutions (pH 6–11) on dissolution kinetics of pure dolomite and Ca and Mg release stoichiometry in flow-through reactor experiments at 25 ± 1 °C. Results revealed that the dolomite dissolution rates obtained from effluent Ca and Mg concentrations (RCa and RMg in mol/cm2/s) were dependent on input solution pH and HCO3 − log activity. The pH dependence of dissolution rates showed two distinct trends, i.e., at circumneutral pH ranging between 6 and 8, the dissolution rate decreased with increasing pH, with minimum rate at pH 8. While in the highly alkaline pH range (pH 9–11), the dolomite dissolution rate increased with an increasing pH. Irrespective of the input pH, the dolomite dissolution rates indicated a reverse relationship with HCO3 − log activity, with the lowest dissolution rate (RCa = 3.80 × 10–12 mol/cm2/s) at pH 8 where HCO3 − log activity attained the highest value (− 3.957). The lower RCa and RMg obtained at pH 8 compared to all the other pH could possibly be attributed to an inhibition caused by high HCO3 − log activity in solution at this pH. Dolomite dissolution rates were non-stoichiometric at all the experimental pH values, showing higher preferential Ca over Mg release (RCa &gt; RMg) whereas an opposite trend was observed at pH 8, with RCa &lt; RMg at the steady state. Saturation index values calculated using geochemical speciation modelling were positive for Mg-bearing minerals (brucite, dolomite, artinite) at alkaline pH of 10–11, indicating favourable conditions for their precipitation under studied conditions. This study provides insights on the significance of log ion activities of HCO3 − and Me-OH+ under varying pH for elucidating the dissolution mechanism of dolomite in circumneutral to alkaline aqueous environments.

Fabrication of Functional Polymers with Gradual Release of a Bioactive Precursor for Agricultural Applications

Biodegradable and biocompatible polymeric materials and stimulus-responsive hydrogels are widely used in the pharmaceutical, agricultural, biomedical, and consumer sectors. The effectiveness of these formulations depends significantly on the appropriate selection of polymer support. Through chemical or enzymatic hydrolysis, these materials can gradually release bioactive agents, enabling controlled drug release. The objective of this work is to synthesize, characterize, and apply two controlled-release polymeric systems, focusing on the release of a phyto-pharmaceutical agent (herbicide) at varying pH levels. The copolymers were synthesized via free radical polymerization in solution, utilizing tetrahydrofuran (THF) as the organic solvent and benzoyl peroxide (BPO) as the initiator, without the use of a cross-linking agent. Initially, the herbicide was grafted onto the polymeric chains, and its release was subsequently tested across different pH environments in a heterogeneous phase using an ultrafiltration (UF) system. The development of these two controlled-release polymer systems aimed to measure the herbicide’s release across different pH levels. The goal is to adapt these materials for agricultural use, enhancing soil quality and promoting efficient water usage in farming practices. The results indicate that the release of the herbicide from the conjugate systems exceeded 90% of the bioactive compound after 8 days at pH 10 for both systems. Furthermore, the two polymeric systems demonstrated first-order kinetics for herbicide release in aqueous solutions at different pH levels. The kinetic constant was found to be higher at pH 7 and 10 compared to pH 3. These synthetic hydrogels are recognized as functional polymers suitable for the sustained release of herbicides in agricultural applications.

Effect of enzyme-probiotic preparation “Profort” on rumen microflora and reproductive function of cows

The aim of the study was to evaluate the effect of enzyme-probiotic feed additive “Profort” on rumen microflora and reproductive function of Holstein cows under conditions of year-round uniform feeding. The object of research were high-yielding cows (n = 40) of Holstein breed, kept loose, in conditions of yearround uniform silage-hay-concentrate type of feeding. In total, two groups of lactating cows of 20 heads in each group were formed: control group with feeding of the basic ration (OR) and experimental group OR + enzymeprobiotic feed additive “Profort” 30.0g per head per day daily, for 15 days, three times with a break of 15 days. “Profort” contains a probiotic mixture consisting of two types of bacteria: Enterococcus faecium 1–35 and Bacillus megaterium B-4801. As a result of the research it was found that the use of feed additive to animals of the experimental group contributed to an increase in the content in the rumen microbiome of cellulosolytic bacteria that activate the breakdown of plant feed fiber: Prevotellaceae, Lachnospiraceae, Clostridia UCG-014, Eubacterium, Oscillospiraceae, Hungateiclostridiaceae, Christensenellaceae and Ruminococcaceae, as well as lactate-utilizing bacteria, preventing the decrease in pH of the rumen environment, reproduction and colonization of opportunistic and pathogenic microflora in other organs of the animal body, including the reproductive system. The cows of the experimental group have improved reproductive ability indicators: fertilizability, decreased duration of service period, labor and postpartum complications. The number of calves obtained in the state of physiological maturity (normotrophy) increases.

Ameliorating macrophage pyroptosis via ANXA1/NLRP3/Caspase-1/GSDMD pathway: Ac2-26/OGP-loaded intelligent hydrogel enhances bone healing in diabetic periodontitis

Craniofacial bone defect healing in periodontitis patients with diabetes background has long been difficult due to increased blood glucose levels which cause overproduction of reactive oxygen species (ROS) and a low pH environment. These conditions negatively affect the function of macrophages, worsen inflammation and oxidative stress, and ultimately, hinder osteoblasts' bone repair potential. In this study, we for the first time found that ANXA1 expression in macrophages was reduced in a diabetic periodontitis environment, with the activation of the NLRP3/Caspase-1/GSDMD signaling pathway, and, eventually, increased macrophage pyroptosis. Next, we have developed a new GPPG intelligent hydrogel system which was ROS and pH responsive, and loaded with Ac2-26, an ANXA1 bioactive peptide, and osteogenic peptide OGP as well. We found that Ac2-26/OGP/GPPG can effectively reduce ROS, mitigates macrophage pyroptosis via the ANXA1/NLRP3/Caspase-1/GSDMD pathway and enhanced osteogenic differentiation. The effect of Ac2-26/OGP/GPPG in regulation of pyroptosis and bone defect repair was also further validated by animal experiments on periodontitis-induced tooth loss model in diabetic rats. To conclude, our study unveils the effect of ANXA1 on macrophage pyroptosis in periodontitis patients with diabetes, based on which we introduced a promising innovative hydrogel system for improvement of bone defects repair in diabetic periodontitis patients via targeting macrophage pyroptosis and enhancing osteogenic potential.

Fe3O4-viral-like Mesoporous Silica Nanoparticle(Fe3O4-vMSN)-Sustained Release of Lenvatinib for Targeted Treatment of Hepatocellular Carcinoma

Background: Lenvatinib is an oral tyrosine kinase inhibitor that selectively inhib-its receptors involved in tumor angiogenesis and tumor growth. It is an emerging first-line treatment agent for hepatocellular carcinoma (HCC). However, there is no intravenous ad-ministration of Lenvatinib. Aims: This study aimed to construct nanocomposites that can efficiently support Lenvatinib and target liver cancer tissues and cells. Objective: In this study, ferric oxide-viral-like mesoporous silica nanoparticles-folic acid (Fe3O4-vMSN-FA) nanocomposites loaded with Lenvatinib were constructed, and their anti-hepatocellular carcinoma effects were evaluated. Methods: The hydrothermal method was used to synthesize ferric oxide (Fe3O4). Ferric ox-ide-viral-like mesoporous silica nanoparticles (Fe3O4-vMSN) were synthesized using a two-phase method. Then, Fe3O4-vMSN was modified with folic acid (Fe3O4-vMSN-FA) to better target tumor cells. Results: The experimental data showed that Fe3O4-vMSN-FA nanocomposites were suc-cessfully synthesized and could be loaded with Lenvatinib (Len@ Fe3O4-vMSN-FA). Fe3O4-vMSN-FA had good stability and biocompatibility, and it can release the loaded Len-vatinib faster in an acidic environment (pH 5.5). CCK8 assay and flow cytometry showed that HepG2 cells in the Len@ Fe3O4-vMSN group had the lowest cell viability and the high-est apoptosis rate, confirming the anticancer properties of Len@ Fe3O4-vMSN-FA in vitro. In addition, transwell experiments showed that the migration and invasion ability of HepG2 cells in the Len@ Fe3O4-vMSN-FA group were significantly inhibited. In vivo fluorescence imaging in mice confirmed the enhanced tumor-targeting ability of Fe3O4-vMSN-FA. The tumor volume of the Len@ Fe3O4-vMSN-FA group was significantly reduced, and there was no significant effect on body weight. Moreover, serum liver function index (ALT and AST) and HE staining showed that Len@ Fe3O4-vMSN-FA did not cause obvious damage to organ tissue. Conclusion: Len@ Fe3O4-vMSN-FA has a good anti-liver cancer effect. Fe3O4-vMSN-FA can be used as an alternative platform for MSCs for drug delivery, providing more options for cancer therapy.

A dual thermo/pH-sensitive hydrogel as 5-Fluorouracil carrier for breast cancer treatment.

Intelligent hydrogels are promising in constructing scaffolds for the controlled delivery of drugs. Here, a dual thermo- and pH-responsive hydrogel called PCG [poly (N-isopropyl acrylamide-co-itaconic acid)/chitosan/glycerophosphate (PNI/CS/GP)] was established as the carrier of 5-fluorouracil (5-FU) for triple-negative breast cancer (TNBC) treatment. The PCG hydrogel was fabricated by blending synthesized [poly (N-isopropyl acrylamide-co-itaconic acid), pNIAAm-co-IA, PNI] with CS in the presence of GP as a crosslinking agent. The interaction between PCG hydrogel compositions was characterized by Fourier transforms infrared, NMR spectroscopy, and scanning electron microscopy. The PCG hydrogel presented an interconnected and porous structure with similar pore size, rapid swelling/deswelling rate in response to both temperature and pH change, and biocompatibility, upon which it was proposed as a great drug carrier. 5-FU had a dual thermo- and pH-responsive controlled release behavior from the PCG hydrogel and displayed an accelerated release rate in an acidic pH environment than in a neutral pH condition. The application of 5-FU-loaded PCG hydrogel exhibited a more promoted anticancer activity than 5-FU against the growth of TNBC cells both in vitro and in vivo. The outcomes suggested that the PCG hydrogel could be an excellent platform for local drug-delivery systems in the clinical therapy of TNBC.