Amine-functionalized Mesoporous Silica Research Articles

Immobilizing Pd nanoparticles on amine-functionalized yolk-shell mesoporous silica nanospheres for efficient H2 production from formic acid dehydrogenation

Ultrafine Pd nanoparticles (NPs), immobilized within amine-functionalized yolk-shell mesoporous silica nanospheres (YSMSNs), have been elaborately prepared to facilitate the highly effective formic acid (FA) dehydrogenation. The optimized Pd/YSMSNs-NH2(10–3, 10 wt% Pd loading and 3 mL of amine treatment on YSMSNs), displays the extraordinary turnover frequency (TOF, 9108 h-1) and stability at 343 K, achieving 100% FA conversion and H2 selectivity, which is higher than other documented heterogeneous catalysts. The radially oriented pore channels can facilitate the mass transfer of reactants. The amine groups on the YSMSNs-NH2 effectively promote the cleavage of the O-H bond within FA. Furthermore, the ultrafine size of the Pd NPs and their high dispersion on the YSMSNs-NH2 provide a wealth of active sites for catalysis. Lastly, the metal-support interaction (MSI) between the Pd NPs and YSMSNs-NH2 further enhances the catalytic performance. This work provides a new strategy into developing effective silica-based heterogeneous catalysts for FA dehydrogenation.

Amine-Functionalized SBA-15 Mesoporous Silica-Anchored Ni Nanocatalyst for CO2 Hydrogenation Reaction

Abstract: In this study, we successfully synthesized amine-functionalized SBA-15 mesoporous silicasupported Nickel nanoparticles (Ni NPs) and investigated their potential for CO2 transition to formic acid via high-pressure hydrogenation reaction. The metal-support interface between the Ni NPs and the amine-functionalized SBA-15 mesoporous silica was examined using various techniques, including BET, TEM, and XPS analyses. Our findings reveal a robust metal-support interaction between the NiNPs and the mesoporous silica substrate, highlighting the suitability of the catalyst for the CO2 conversion reaction. Additionally, the catalyst CAT$Ni-1 exhibited good catalytic activity over CAT$Ni-2 and CAT$Ni-3, and we were able to recycle them up to five runs with no significant reduction in catalytic activity. These results suggest that the synthesized Ni NP catalysts have the potential for large-scale CO2 conversion, contributing to the development of sustainable technologies for reducing greenhouse gas emissions.

Hydrogel Contact Lenses Embedded with Amine-Functionalized Large-Pore Mesoporous Silica Nanoparticles with Extended Hyaluronic Acid Release.

Contact lenses (CLs) have emerged as an effective method for delivering ophthalmic drugs. In this research, we designed hydrogel CLs capable of extended release, utilizing large-pore mesoporous silica nanoparticles (LPMSNs) to deliver hyaluronic acid (HA) for treating dry eye syndrome. LPMSNs were functionalized with amine groups (LPMSN-amine) to enhance HA loading and release capacity. In vitro release studies demonstrated that LPMSN-amine CLs exhibited superior slower HA release than LPMSN-siloxane and standard CLs. Within 120 h, the cumulative amount of HA released from LPMSN-amine CLs reached approximately 275.58 µg, marking a 12.6-fold improvement compared to standard CLs, when loaded from 0.1 wt% HA solutions. Furthermore, LPMSN-amine CLs effectively maintained moisture, mitigating ocular surface dehydration, making them a promising solution for dry eye management. This study successfully developed LPMSN-amine CLs for extended HA release, identifying the optimal functional groups and loading conditions to achieve sustained release.

Size variations of mesoporous silica nanoparticle control uptake efficiency and delivery of AC2-derived dsRNA for protection against tomato leaf curl New Delhi virus.

We report the size dependent uptake of dsRNA loaded MSNPs into the leaves and roots of Nicotiana benthamiana plants and accessed for their relative reduction in Tomato leaf curl New Delhi viral load. A non-GMO method of RNA interference (RNAi) has been recently in practice through direct delivery of double stranded RNA into the plant cells. Tomato leaf curl New Delhi virus (ToLCNDV), a bipartitie begomovirus, is a significant viral pathogen of many crops in the Indian subcontinent. Conventional RNAi cargo delivery strategies for instance uses viral vectors and Agrobacterium-facilitated delivery, exhibiting specific host responses from the plant system. In the present study, we synthesized three different sizes of amine-functionalized mesoporous silica nanoparticles (amino-MSNPs) to mediate the delivery of dsRNA derived from the AC2 (dsAC2) gene of ToLCNDV and showed that these dsRNA loaded nanoparticles enabled effective reduction in viral load. Furthermore, we demonstrate that amino-MSNPs protected the dsRNA molecules from nuclease degradation, while the complex was efficiently taken up by the leaves and roots of Nicotiana benthamiana. The real time gene expression evaluation showed that plants treated with nanoparticles of different sizes ~ 10nm (MSNPDEA), ~ 32nm (MSNPTEA) and ~ 66nm (MSNPNH3) showed five-, eleven- and threefold reduction of ToLCNDV in N. benthamiana, respectively compared to the plants treated with naked dsRNA. This work clearly demonstrates the size dependent internalization of amino-MSNPs and relative efficacy in transporting dsRNA into the plant system, which will be useful in convenient topical treatment to protect plants against their pathogens including viruses. Mesoporous silica nanoparticles loaded with FITC, checked for its uptake into Nicotiana benthamiana.

PdIr nanoparticles on NH2-functionalized dendritic mesoporous silica nanospheres for efficient dehydrogenation of formic acid

Developing highly efficient solid catalysts for formic acid (HCOOH, FA) dehydrogenation is essential to utilize FA as a hydrogen (H2) carrier. In this work, ultrafine bimetallic PdIr nanoparticles (NPs) supported on the amine-functionalized dendritic mesoporous silica nanospheres (PdIr/DMSNs-NH2) have been successfully synthesized by the simple surface functionalization and co-reduction method. The optimized Pd4Ir1/DMSNs-NH2 (Pd/Ir molar ratio = 4:1) catalyst displayed the remarkable catalytic performance with 100 % H2 selectivity of the FA dehydrogenation, and the initial turnover frequency (TOF) could achieve 1333 h−1 with the additive of sodium formate (SF) at 298 K, which is comparable to the most effective mesoporous silica supported Pd-containing solid catalysts. The activation energy (Ea) for the FA dehydrogenation of Pd4Ir1/DMSNs-NH2 catalyst in the FA-SF mixture is 39.7 KJ/mol, lower than most reported catalysts. Furthermore, the optimized catalyst maintained 100 % H2 selectivity even after five runs, only with a negligible decrease in the activity, displaying the excellent stability of the catalyst. The superior catalytic performance could be attributed to the synergistic effect of open dendritic pore channel, high dispersion and ultrafine size of PdIr NPs as the active sites on DMSNs-NH2, and regulated electronic effects of Pd and Ir. More importantly, introducing –NH2 groups to the DMSNs could facilitate the O–H bond dissociation of FA and improve the FA dehydrogenation activity under mild conditions. This work will significantly promote FA as a hydrogen carrier on fuel cells.

PCL/gelatin nanofibers embedded with doxorubicin-loaded mesoporous silica nanoparticles/silver nanoparticles as an antibacterial and anti-melanoma cancer

Melanoma cancer wound healing is critical and complex and poses a significant challenge to researchers. Drug resistance, adverse side effects, and inefficient localization of chemotherapeutic drugs limit common treatment strategies in melanoma cancer. Using drug delivery nanostructures with low side effects and high efficiency, besides having antibacterial and antiseptic properties, can effectively repair the damage caused by the disease. To this end, this study aimed to develop a drug delivery nanosystem based on doxorubicin (DOX)-loaded amine-functionalized mesoporous silica nanoparticles (MSNs), linked with green synthesized silver nanoparticles (AgNPs). Characterization methods including microscopic methods and X-ray diffraction (XRD) confirmed the synthesis and functionalization of the well-dispersed nanoparticles with nanosized and uniform structures. The poly(ε-caprolactone) (PCL) nanofibers as a strong scaffold were produced by the blow spinning method and DOX-loaded nanoparticles were blow spun on PCL nanofibers along with gelatin solution. The resulting nanosystem including nanofibers and nanoparticles (NFs/NPS) showed a fine loading percent with a proper release profile of DOX and AgNPs and low hemolysis activity. Moreover, besides preventing infection by AgNPs, the DOX-loaded NFs/NPs could effectively destroy melanoma cancer cells. The attachment of normal cells to the nanoparticles-loaded nanofibers scaffold revealed the possibility of healing wounds caused by melanoma cancer.

Repurposing Anthelmintics: Rafoxanide- and Copper-Functionalized SBA-15 Carriers against Methicillin-Resistant Staphylococcus aureus.

The development of materials that can more efficiently administer antimicrobial agents in a controlled manner is urgently needed due to the rise in microbial resistance to traditional antibiotics. While new classes of antibiotics are developed and put into widespread usage, existing, inexpensive compounds can be repurposed to fight bacterial infections. Here, we present the synthesis of amine-functionalized SBA-15 mesoporous silica nanomaterials with physisorbed rafoxanide (RFX), a commonly used salicylanilide anthelmintic, and anchored Cu(II) ions that exhibit enhanced antimicrobial efficacy against the pathogenic bacterium Staphylococcus aureus. The synthesized nanomaterials are structurally characterized by a combination of physicochemical, thermal, and optical methods. Additionally, release studies are carried out in vitro to determine the effects of pH and the synthetic sequence used to produce the materials on Cu(II) ion release. Our results indicate that SBA-15 mesoporous silica nanocarriers loaded with Cu(II) and RFX exhibit 10 times as much bactericidal action against wild-type S. aureus as the nanocarrier loaded with only RFX. Furthermore, the synthetic sequence used to produce the nanomaterials could significantly affect (enhance) their bactericidal efficacy.

Biodegradable Dual-Function Nanocomposite Hydrogels for Prevention of Bisphosphonate-Related Osteonecrosis of the Jaw.

This study presents the development of composite hydrogels, comprising a biodegradable polymer (carboxymethyl chitosan (CMCS or CM)) and a mixture of plasma-treated mesoporous silica nanoparticles (PMCM-41 or PM) and amine-functionalized mesoporous silica nanoparticles (NMCM-41 or NM), coloaded with a hydrophilic antibiotic (clindamycin hydrochloride (CDM or C)) and a poorly water-soluble compound (geranylgeraniol (GGOH or G)) for prevention of bisphosphonate-related osteonecrosis of the jaw (BRONJ). The CG-loaded hydrogel stabilities were better maintained when CDM-preloaded PMCM-41 and NMCM-41 were initially used and governed by weight ratios of CDM-loaded PMCM-41 to NMCM-41 and CDM quantity utilized. 5PM240C-1NM-CM demonstrated the best CDM-loaded hydrogel for GGOH postloading. The scanning electron microscopy (SEM) and X-ray microcomputer-tomography (μCT) images of 5PM240C-1NM-CM revealed a porous structure with homogeneously distributed nanoparticles. Two GGOH-loaded 5PM240C-1NM-CM hydrogels were generated after GGOH loadings. Their biphasic drug release profiles were fitted by Ritger-Peppas and Hixson-Crowell models. The copresence of GGOH could hinder CDM releases, while GGOH was released with a slower rate. The hydrogels prolonged the CDM and GGOH releases up to 9 days. They possessed antibacterial activities against Streptococcus sanguinis for up to 14 days and satisfactorily provided good cytoprotection against zoledronic acid for osteoclastic and osteoblastic progenitors, thus preserving a pool of viable progenitor cells that had the capacity to differentiate into mature osteoclasts and osteoblasts in vitro, suggesting their potential local application for prevention of BRONJ.

Synthesis of spherical amine-functionalized silica molecular sieve and application as selective adsorbents for aromatic hydrocarbons analysis

In this work, spherical amine-functionalized mesoporous silica (Sp-Amino-Si) molecular sieve was fabricated by an acid hydrothermal method using 3-aminopropyltriethoxysilane as a modifier and toluene as the solvent. The results of scanning electron microscopy, Barrett-Joyner-Halenda pore size distribution, Fourier transform-infrared spectroscopy, and low-angle X-ray diffraction patterns revealed that the Sp-Amino-Si was monodispersed microspheres with uniform and controllable pore sizes sharing two-dimensional hexagonal P6mm symmetry and a large number of amino groups. The Sp-Amino-Si molecular sieve was verified to be suitable for the selective separation of aromatic hydrocarbons (AMHs) containing two fused benzene rings among other compounds from environmental water matrix. Under the optimized conditions, the Sp-Amino-Si exhibited much higher adsorption efficiency for AMHs (above 88.19%), comparing to the original SBA-15 (below 44.52%). The maximum adsorption capacities for naphthalene, methyl naphthalene, 2-methyl naphthalene, and acenaphthene were 477.1, 1006.5, 893.3, and 1253.2 µg·g−1, respectively. The high selectivity of Sp-Amino-Si for the four AMHs attributed to the size sieving and p-π interactions between the lone pair electrons of amine groups and the π-electrons in AMHs molecules. The Sp-Amino-Si based solid-phase extraction coupled with high performance liquid chromatography detection method was constructed for the analysis of the four AMHs, and the recoveries of spiked AMHs ranged from 89.67% to 112.74% with a relative standard deviation lower than 5.75%. This study provides some inspiration and a reliable method for AMHs separation, removal, and analysis.

Chromic hydroxide-decorated palladium nanoparticles confined by amine-functionalized mesoporous silica for rapid dehydrogenation of formic acid.

Formic acid (FA), one of the products of biomass conversion and CO2 reduction, has attracted much attention as a renewable liquid hydrogen carrier with a high hydrogen content (4.4wt%). Searching for efficient catalysts to realize hydrogen evolution from FA are highly desired but challenging. Herein, ultrafine and mono-dispersed Pd-Cr(OH)3 nanoparticles (1.3nm) loaded on amine-functionalized mesoporous silica (AFMS) have been prepared and applied as an effective catalyst for rapid hydrogen production from additive-free FA. The as-synthesized Pd-Cr(OH)3/AFMS catalysts exhibited efficient catalytic activity and 100% hydrogen selectivity and conversion toward FA dehydrogenation reaction without additives, giving an initial TOF value of 3112h-1 at 323K, which is comparable to most of the highly efficient heterogeneous catalysts reported so far under similar reaction conditions. This work provides a feasible idea for the design metal hydroxide-modified Pd-based efficient heterogeneous catalyst, which is expected to enhance the application of FA in fuel cells.

Synthesis, characterization, and use of an amine-functionalized mesoporous silica SBA-15 for the removal of Congo Red from aqueous media

Synthesis, characterization, and use of an amine-functionalized mesoporous silica SBA-15 for the removal of Congo Red from aqueous media

Ultrasonic-assisted d-µ-SPE based on amine-functionalized KCC-1 for trace detection of lead and cadmium ion by GFAAS

In this work, an efficient ultrasonic-assisted dispersive micro-solid phase extraction method (ultrasonic-assisted d-µSPE), based on amine-functionalized mesoporous silica KCC-1, was successfully utilized for the extraction and highly sensitive detection of lead and cadmium ions in water and agricultural products. The lead and cadmium ions were determined by graphite furnace atomic absorption spectrometry (GFAAS). In addition, the impact of significant factors, including pH, sorbent mass, and the sonication time in the retention step and concentration of the eluent, volume of the eluent, and the sonication time in the elution step was optimized using the Box-Behnken design. The obtained models by the Box-Behnken design for the retention and elution steps were meticulously evaluated. The results show that the proposed models for predicting and optimizing influencing parameters in the pre-concentration procedure have good adequacy and accuracy. In the optimal pre-concentration conditions, the calibration curves were linear in the range of 0.08–1.4 µg/L for cadmium and 0.6–30 µg/L for lead ions. The limits of quantification (LOQ) and the limits of detection (LOD) were 0.08 µg/L and 0.02 µg/L for cadmium ions and 0.60 µg/L and 0.18 µg/L for lead ions. The obtained relative recovery values from the analysis of spiked real samples were in the 97.2–104.0 % and 98.0–107.0 % range for cadmium and lead ions, respectively. Intra-day and inter-day relative standard deviations were 4.4 and 6.1 % for cadmium ions and 2.9 and 4.9 % for lead ions (1.0 µg/L; Number of replicate = 3).

CO2 capture-driven thermal battery using functionalized solvents for plus energy building application

Renewable energy has the drawback of intermittent power generation, and it should be linked to an energy storage system. However, the efficiency and density of the conventional thermal energy storage technologies are low. Herein, for building applications, CO2 capture-driven thermal battery has been developed using solvents composed of amine-functionalized mesoporous silica (3-APTES-SBA-15) and an amine absorbent (MEA). The thermal energy is discharged through the exothermic reaction of amine-CO. When the renewable energy is supplied to the battery, amine-CO2 bonds are broken, which corresponds to charging process. 3-APTES-SBA-15/MEA presents a superior energy storage density of 2.187 kJ/g and an efficiency of 91.5%. It is sufficient for producing heating/hot water considering the discharging temperature, and there is no loss even if stored for a long time. The thermal battery system presents a coefficient of performance of 0.66 and a thermal energy storage density of 0.57 kJ/g. When the thermal battery is combined with solar thermal energy harvesting system, the thermal and electric energy consumptions are reduced by 22.0% (477.9 MJ/m2) and 19.6% (156.9 MJ/m2), respectively. The CO2 capture-driven thermal battery will contribute to manage renewable energy and reduce grid energy consumption for building applications.

Adsorptive colorimetric determination of chromium(VI) ions at ultratrace levels using amine functionalized mesoporous silica

There is an urgent need for a rapid, affordable and sensitive analytical method for periodic monitoring of heavy metals in water bodies. Herein, we report for the first time a versatile method for ultratrace level metal detection based on colorimetric sensing. The method integrates preconcentration using a nanomaterial with a colorimetric assay performed directly on the metal-enriched nanomaterial surface. This method circumvents the need for tedious sample pre-processing steps and the complex development of colorimetric probes, thereby reducing the complexity of the analytical procedure. The efficacy of the proposed method was demonstrated for chromium(VI) ions detection in water samples. Amine functionalized mesoporous silica (AMS) obtained from a one-pot synthesis was utilized as a pre-concentration material. The structural and chemical analysis of AMS was conducted to confirm its physico-chemical properties. The pre-concentration conditions were optimized to maximise the colorimetric signal. AMS exhibited a discernible colour change from white to purple (visible to the naked eye) for trace Cr(VI) ions concentration as low as 0.5 μg L−1. This method shows high selectivity for Cr(VI) ions with no colorimetric signal from other metal ions. We believe our method of analysis has a high scope for de-centralized monitoring of organic/inorganic pollutants in resource-constrained settings.

Amine-functionalized and non-functionalized mesoporous silica nanoparticles as the delivery system for tertiary butylhydroquinone (TBHQ)

Amine-functionalized and non-functionalized mesoporous silica nanoparticles as the delivery system for tertiary butylhydroquinone (TBHQ)

Amine-Functionalized Mesoporous Silica Adsorbent for CO2 Capture in Confined-Fluidized Bed: Study of the Breakthrough Adsorption Curves as a Function of Several Operating Variables

Carbon capture, utilization, and storage (CCUS) is one of the key promising technologies that can reduce GHG emissions from those industries that generate CO2 as part of their production processes. Compared to other effective CO2 capture methods, the adsorption technique offers the possibility of reducing the costs of the process by setting solid sorbent with a high capacity of adsorption and easy regeneration and, also, controlling the performance of gas-solid contactor. In this work, an amine-functionalized mesoporous sorbent was used to capture CO2 emissions in a confined-fluidized bed. The adoption of a confined environment allows the establishment of a homogeneous expansion regime for the sorbent and allows to improve the exchange of matter and heat between gas and solid phase. The results illustrate how the different concentration of the solution adopted during the functionalization affects the adsorption capacity. That, measured as mg of CO2 per g of sorbent, was determined by breakthrough curves from continuous adsorption tests using different concentrations of CO2 in air. Mesoporous silica functionalized with a concentration of 20% of APTES proves to be the best viable option in terms of cost and ease of preparation, low temperature of regeneration, and effective use for CO2 capture.

Effective adsorption and immobilization of Cr(VI) and U(VI) from aqueous solution by magnetic amine-functionalized SBA-15

• A magnetic amine-functionalized SBA-15 was fabricated successfully. • Adsorption conditions played an important role in uptake of Cr(VI) and U(VI). • Adsorbents exhibited satisfying adsorption performance for Cr(VI) and U(VI). • Adsorption mechanism was conformed by SEM, FT-IR and XPS techniques. Herein, a magnetic amine-functionalized mesoporous silica SBA-15 (Fe 3 O 4 @SBA-15-PDA/HBP-NH 2 ) adsorbent was fabricated by loading Fe 3 O 4 nano-particles on amino-terminated hyperbranched polymers (HBP-NH 2 ) functionalized SBA-15 and exploited for chromium (VI) and uranium (VI) elimination. The morphologies and microstructures of as-obtained materials were observed using different physicochemical and spectroscopic techniques. Meanwhile, batch experiments were performed to investigate the impacts of various water environment conditions on removal process including solution pH, equilibrium time and temperatures. The maximum adsorption capacities of U(VI) and Cr(VI) on Fe 3 O 4 @SBA-15-PDA/HBP-NH 2 reached up to 77.4 mg/g and 66.5 mg/g under optimal water environment conditions. Moreover, the characterization analysis manifested that removal of U(VI) was fulfilled through the surface complexation with amino and phenolic hydroxyl groups, while Cr(VI) were firstly electrostatically adsorbed, and subsequently reduced to less toxic Cr(III) by phenolic hydroxyl groups. These findings demonstrated that this new magnetic amine-functionalized SBA-15 could be considered as valuable materials in environmental cleanup.

In Vitro Efficacy of Curcumin-Loaded Amine-Functionalized Mesoporous Silica Nanoparticles against MCF-7 Breast Cancer Cells.

Purpose: Mesoporous silica nanoparticles (MSNs) have drawn substantial interest as drug nanocarriers for breast cancer therapy. Nevertheless, because of the hydrophilic surfaces, the loading of well-known hydrophobic polyphenol anticancer agent curcumin (Curc) into MSNs is usually very low. Methods: For this purpose, Curc molecules were loaded into amine-functionalized MSNs (MSNs-NH2 -Curc) and characterized using thermal gravimetric analysis (TGA), Fourier-transform infrared (FTIR), field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM), Brunauer-Emmett-Teller (BET). MTT assay and confocal microscopy, respectively, were used to determine the cytotoxicity and cellular uptake of the MSNs-NH2 - Curc in the MCF-7 breast cancer cells. Besides, the expression levels of apoptotic genes were evaluated via quantitative polymerase chain reaction (qPCR) and western blot. Results: It was revealed that MSNs-NH2 possessed high values of drug loading efficiency and exhibited slow and sustained drug release compared to bare MSNs. According to the MTT findings, while the MSNs-NH2 -Curc were nontoxic to the human non-tumorigenic MCF-10A cells at low concentrations, it could considerably decrease the viability of MCF-7 breast cancer cells compared to the free Curc in all concentrations after 24, 48 and 72 hours exposure times. A cellular uptake study using confocal fluorescence microscopy confirmed the higher cytotoxicity of MSNs-NH2 -Curc in MCF-7 cells. Further, it was found that the MSNs-NH2 -Curc could drastically affect the mRNA and protein levels of Bax, Bcl-2, caspase 3, caspase 9, and hTERT relative to the free Curc treatment. Conclusion: Taken together, these preliminary results suggest the amine-functionalized MSNs-based drug delivery platform as a promising alternative approach for Curc loading and safe breast cancer treatment.

Antimicrobial action of mesoporous silica nanoparticles loaded with cefepime and meropenem separately against multidrug-resistant (MDR) Acinetobacter baumannii

The extensive use of antibiotics drives the evolution of drug resistance in pathogenic bacteria clearly. Multidrug-resistance (MDR) is being a major challenge in world public health and A. baumannii is becoming an increasingly important human pathogen due to the emergence of MDR strains. In this study, amine-functionalized mesoporous silica nanoparticles (MSN-NH2) was synthesized and loaded by cefepime (CEF) and meropenem (MEP) as antibiotic drugs. The results showed a high loading efficiency of the CEF and MEP into MSN-NH2 (MSN–NH2–CEF and MSN–NH2–MEP). The prepared nanoparticles were fully characterized by Scanning Electron Microscopy (SEM), nitrogen adsorption/desorption isotherms, Fourier Transform Infrared (FT-IR) spectroscopy, and X-ray Diffraction (XRD) spectroscopy. In order to determine the antibacterial action of MSN–NH2–CEF and MSN–NH2–MEP against MDR A. baumannii, the broth microdilution and well diffusion method were used. The antimicrobial test results against MDR A. baumannii isolate were showed that drug-loaded MSN-NH2 more effective than the free drug. The results of the present study demonstrated that MSN–NH2–CEF and MSN–NH2–MEP potentiate antimicrobial activity than free drugs and enhanced the possibility of combat against A. baumannii isolate.

Isolation and Quantification of miRNA from the Biomolecular Corona on Mesoporous Silica Nanoparticles.

To understand the factors that control the formation of the biomolecular corona, a systematic study of the adsorption of several miRNAs shown to be important in prostate cancer on amine-functionalized mesoporous silica nanoparticles (MSN-NH2) has been performed. Process parameters including miRNA type, nanoparticle concentration, incubation temperature and incubation time were investigated, as well as the potential competition for adsorption between different miRNA molecules. The influence of proteins and particle PEGylation on miRNA adsorption were also explored. We found that low particle concentrations and physiological temperature both led to increased miRNA adsorption. Adsorption of miRNA was also higher when proteins were present in the same solution; reducing or preventing protein adsorption by PEGylating the MSNs hindered adsorption. Finally, the amount of miRNA adsorbed from human serum by MSN-NH2 was compared to a commercial miRNA purification kit (TaqMan®, Life Technologies, Carlsbad, CA, USA). MSN-NH2 adsorbed six times as much miRNA as the commercial kit, demonstrating higher sensitivity to subtle up- and downregulation of circulating miRNA in the blood of patients.