Silica Nanostructures Research Articles

Role of Folic Acid in the Therapeutic Action of Nanostructured Porous Silica Functionalized with Organotin(IV) Compounds Against Different Cancer Cell Lines.

The synthesis, characterization and cytotoxic activity against different cancer cell lines of various mesoporous silica-based materials containing folate targeting moieties and a cytotoxic fragment based on a triphenyltin(IV) derivative have been studied. Two different mesoporous nanostructured silica systems have been used: firstly, micronic silica particles of the MSU-2 type and, secondly, mesoporous silica nanoparticles (MSNs) of about 80 nm. Both series of materials have been characterized by different methods, such as powder X-ray diffraction, X-ray fluorescence, absorption spectroscopy and microscopy. In addition, these systems have been tested against four different cancer cell lines, namely, OVCAR-3, DLD-1, A2780 and A431, in order to observe if the size of the silica-based systems and the quantity of incorporated folic acid influence their cytotoxic action. The results show that the materials are more active when the quantity of folic acid is higher, especially in those cells that overexpress folate receptors such as OVCAR-3 and DLD-1. In addition, the study of the potential modulation of the soluble folate receptor alpha (FOLR1) by treatment with the synthesized materials has been carried out using OVCAR-3, DLD-1, A2780 and A431 tumour cell lines. The results show that a relatively high concentration of folic acid functionalization of the nanostructured silica together with the incorporation of the cytotoxic tin fragment leads to an increase in the quantity of the soluble FOLR1 secreted by the tumour cells. In addition, the studies reported here show that this increase of the soluble FOLR1 occurs presumably by cutting the glycosyl-phosphatidylinositol anchor of membrane FR-α and by the release of intracellular FR-α. This study validates the potential use of a combination of mesoporous silica materials co-functionalized with folate targeting molecules and an organotin(IV) drug as a strategy for the therapeutic treatment of several cancer cells overexpressing folate receptors.

Noble Metal Nanoparticles Incorporated Siliceous TUD-1 Mesoporous Nano-Catalyst for Low-Temperature Oxidation of Carbon Monoxide.

This report, for the first time, demonstrated the low-temperature oxidation of carbon monoxide (CO) using nano-catalysts consisting of noble metal nanoparticles incorporated in TUD-1 mesoporous silica nano-structures synthesized via a one-pot surfactant-free sol–gel synthesis methodology. Herein, we investigated a nano-catalyst, represented as M-TUD-1 (M = Rh, Pd, Pt and Au), which was prepared using a constant Si/M ratio of 100. The outcome of the analytical studies confirmed the formation of a nano-catalyst ranging from 5 to 10 nm wherein noble metal nanoparticles were distributed uniformly onto the mesopores of TUD-1. The catalytic performance of M-TUD-1 catalysts was examined in the environmentally impacted CO oxidation reaction to CO2. The catalytic performance of Au-TUD-1 benchmarked other M-TUD-1 catalysts and a total conversion of CO was obtained at 303 K. The activity of the other nano-catalysts was obtained as Pt-TUD-1 > Pd-TUD-1 > Rh-TUD-1, with a total CO conversion at temperatures of 308, 328 and 348 K, respectively. The Au-TUD-1 exhibited a high stability and reusability as indicated by the observed high activity after ten continuous runs without any treatment. The outcomes of this research suggested that M-TUD-1 are promising nano-catalysts for the removal of the toxic CO gas and can also potentially be useful to protect the environment where a long-life time, cost-effectiveness and industrial scaling-up are the key approaches.

Synthesis, charaterization and optical properties of nanostructured silica hybrid materials obtained by soft chemistry from perhydropolysilazane/1,2,4-triazole precursors

Nanostructured silica hybrid materials have been synthesized via soft chemistry way, by the incorporation of functional 1,2,4-triazole components into a silica network, using a perhydropolysilazane (PHPS) as a silica source and 1,2,4-triazole components as templates. The compositions, morphological and textural properties of the as-synthesized samples have been studied by 13C and 29Si CP MAS NMR, FTIR and SEM. The spectroscopy results suggest that the organic moieties have been chemically linked to the silica skeleton leading to hybrid materials in which Si–N, Si–O and Si–S bridges are created. Nitrogen adsorption-desorption analysis (BET) shows that the surface area varied between 385 and 425 m2 g−1. The 29Si CP-MAS NMR displays signals between -70 and -120 ppm corresponding to Q2, Q3 and Q4 units. The optical properties have been studied also by UV–visible diffuse reflection spectroscopy and photoluminescence (PL). This study reveals that the direct gap energies varied between 0.71 and 2.53 eV. Photoluminescence shows that the silica nanohybrids are suitable to the emission of blue light with wavelength (λem) values of about 470-480 nm. The PL emission results also from some silicon/oxygen-related defect species.

Utilization of nanoporous biosilica of diatoms as a potential source material for fabrication of nanoelectronic device and their characterization

Biosilica obtained from frustules of diatoms have very delicate nanostructures similar to many micro- and nanofluidic devices. In the present investigation, a cheaper and ecofriendly metal-oxide-semiconductor (MOS) tool has been fabricated exploiting frustules of the diatom Halamphora subturgida. The structural, optical, and chemical characterizations of the cleaned frustules of cultured diatom were investigated through various techniques. Electron microscopic images revealed intricate morphology of the nanostructured silica with very minute pores making the frustules very hard but light material. UV-Vis spectroscopy showed maximum absorbance at 223 nm. The absorption maximum for photoluminescence was centered at 462 nm and that of cathodoluminescence was at 439.9 nm and 466.6 nm. Bulk of extracted silicon dioxide (SiO2) nano-powder from diatom frustules was used as a source material for preparing a high-quality crystalline film on P-type silicon (p-Si) by vapor-liquid-solid (VLS) method. The crystalline quality of the film was tested by X-ray diffraction (XRD) and the crystalline size obtained was 62 ± 2.4 nm. From scanning electron microscopic (SEM) investigation, the growth of a continuous film from diatom biosilica on p-Si substrate was revealed. The thickness of the as-grown SiO2 film was 22.2 ± 1.6 nm, obtained from spectroscopic ellipsometry (SE) study. The performances of fabricated Al/SiO2/Si metal-oxide-semiconductor capacitor were tested by measuring leakage current (~ 43 ± 8 × 10−11 A μm−2 at +2 V), capacitance-voltage, constant current (0.1 μA), and voltage stress (at − 2 V) for reliable gate dielectrics applications in MOS devices. Overall, the process was cost-effective and provides an alternative technique to design high-quality diatom-derived “Bio-SiO2 films” on p-Si substrate.

Enhanced one- and two-photon pumped amplified spontaneous emissions of Ag-SiO2 core-shell nanowire composite embedded CH3NH3PbBr3 in SiO2 mesopores

Benefiting from high-performance of photoelectric, hybrid organic-inorganic perovskite shows great development potential. We introduce a composite nanostructure of monolayer well-organized mesoporous silica, with a wrapped silver nanowire as a core. A gain material, methyl ammonium lead bromide (MAPbBr3) was embedded in mesoporous silica (mSiO2). Using 400-nm and 800-nm femtosecond lasers for pumping, which were corresponding to one-photon and two-photon regimes, the laser sign peaks appeared at 549 nm and 546 nm. The amplified spontaneous emissions (ASE) were observed, as well, giant enhancements of ASE can be obtained due to the localized field of surface plasmon resonance caused by silver-core. Compared with composites without silver nanowire cores to enhance the field distribution, the thresholds are significantly down to ∼62% and 32% of original values under 400-nm and 800-nm femtosecond lasers pump, respectively.

Photonic Crystal Enhanced SERS Detection of Analytes Separated by Ultrathin Layer Chromatography Using a Diatom Frustule Monolayer

AbstractDiatoms are single‐celled algae that biologically fabricate nanostructured silica shells with ordered pore arrays called frustules that resemble a 2D photonic crystal. A monolayer of Pinnularia frustules isolated from cell culture is deposited on a glass substrate and then conformally coated with silver nanoparticles (AgNPs) to serve as a nanostructured thin film for ultrathin layer chromatography (UTLC). Malachite green and Nile red are resolved in toluene mobile phase and the separated analytes are profiled micro‐Raman spectroscopy, where plasmonic AgNPs provide surface‐enhanced Raman scattering (SERS). The AgNP‐diatom frustule monolayer improves SERS detection of malachite green by an average factor of 1.8 ± 0.1 over the plasmonic AgNP layer on glass. Analysis of hot spots on the AgNP‐diatom frustule monolayer reveals that nearly 20% of the SERS active area intensifies the SERS signal at least tenfold over the SERS signal for AgNP on glass. Diatom‐SERS enhancement is attributed to guided‐mode resonances of the Raman laser source, which in turn further enhances the localized surface plasmonic resonance from AgNPs. Overall, the AgNP‐diatom frustule monolayer thin film is a new functional material that uniquely enables separation of analytes by UTLC, quantitative SERS detection of separated analytes, and photonic enhancement of the SERS signals.

Nanoestructuras de sílice, con diámetro y distribución de mesoporos variable, modificadas con ácido tungstofosfórico como catalizadores en la síntesis de quinoxalinas

Se sintetizaron catalizadores (SNX#WPA) basados en ácido tungstofosfórico, en soportes de nanoestructuras de sílice (SNX), con distribución de diámetros y tamaños de mesoporos variables. Las SNX se prepararon en medio de octano/agua, usando poliestireno y bromuro de cetiltrimetilamonio como plantillas. Los materiales se caracterizaron por DRX, TEM y adsorción/desorción de nitrógeno. La relación octano/agua influyó tanto en la morfología y el tamaño de las SNX como en la distribución del tamaño de poro. Las SNX obtenidas utilizando relaciones OCT/H2O en el rango de 0,07-0,35, presentan mesoporos pequeños (5-6 nm) y grandes (28-34 nm), generados principalmente por poliestireno. Los mesoporos grandes y su contribución de volumen fueron claramente más altos que en las muestras SN1, SN2 y SN3. La estructura y la morfología de SNX#WPA fueron similares a las de las SNX usadas como soporte. Además, la caracterización de todos los materiales SNX#WPA por FT-IR y 31P NMR indicó la presencia de especies [PW12O40]3− y [H3-XPW12O40](3-X)− sin degradar. Según los resultados de la valoración potenciométrica, los sólidos presentaron sitios ácidos muy fuertes. Se evaluó la actividad de SNX#WPA como catalizadores en la síntesis de quinoxalinas, a partir de lo cual se obtuvieron altos rendimientos, sin formación de subproductos. De ello resultó que los materiales preparados son catalizadores altamente selectivos y reutilizables.

Site-Specific Synthesis of Silica Nanostructures on DNA Origami Templates.

DNA origami has been widely investigated as a template for the organization of various functional elements, leading to potential applications in many fields such as biosensing, nanoelectronics, and nanophotonics. However, the synthesis of inorganic nonmetallic nanomaterials with predesigned patterns using DNA origami templates has seldom been explored. Here, a novel method is reported to site-specifically synthesize silica nanostructures with designed patterns on DNA origami templates. The molecular dynamic simulation confirms that the positively charged silica precursors have a stronger electrostatic affinity to protruding double-stranded DNA (dsDNA) than DNA origami surfaces. The work describes a novel strategy to fabricate silica nanostructures with nanoscale precision. Moreover, the site-specific silicification of DNA nanoarchitectures expands the scope of customized synthesis of inorganic nonmetallic nanomaterials.

Two-Dimensional Superstructures of Silica Cages.

Despite extensive studies on mesoporous silica since the early 1990s, the synthesis of two-dimensional (2D) silica nanostructures remains challenging. Here, mesoporous silica is synthesized at an interface between two immiscible solvents under conditions leading to the formation of 2D superstructures of silica cages, the thinnest mesoporous silica films synthesized to date. Orientational correlations between cage units increase with increasing layer number controlled via pH, while swelling with oil and mixed surfactants increase micelle size dispersity, leading to complex clathrate type structures in multilayer superstructures. The results suggest that a three-dimensional (3D) crystallographic registry within cage-like superstructures emerges as a result of the concerted 3D co-assembly of the organic and inorganic components. Mesoporous 2D superstructures can be fabricated over macroscopic film dimensions and stacked on top of each other. The realization of previously inaccessible mesoporous silica heterostructures with separation or catalytic properties unachievable via conventional bulk syntheses is envisioned.

Synthesis of structurally enhanced magnetite cored poly(propyleneimine) dendrimer nanohybrid material and evaluation of its functionality in sustainable catalysis of condensation reactions

The conventional method of dendrimer synthesis especially poly(propyleneimine) dendrimer (PPI) involves complicated reaction workup and tedious separation strategies. Since it has greater number of nitrogen atom in their structure, its applications are innumerable in different fields. But the PPI dendrimer is used once, it cannot be recycled for subsequent utility. In order to overcome these issues, for the first time divergent synthesis of poly(propyleneimine) dendrimer G3 on silica coated magnetite has been achieved with structurally enhanced PPI dendrimer on core-shell type magnetic silica nanostructure. This nanohybrid material was characterized by using HRTEM, FTIR, XRD, TGA, XPS and VSM studies. Further, nitrogen concentration of PPI dendrimer was quantified by conductometric titration and Prussian blue complex methods. The probing of catalytic efficacy of structurally enhanced magnetite cored poly(propyleneimine) dendrimer G3 as magnetically recyclable heterogeneous organic base catalyst was employed for representative reactions such as Knoevenagel condensation, Knoevenagel-Michael cyclocondensation and Henry reaction at ambient conditions. The catalyst was reused for minimum of eight cycles without significant loss of its catalytic activity.

Adsorption of Fibrinogen on Silica Surfaces-The Effect of Attached Nanoparticles.

When a biomaterial is inserted into the body, proteins rapidly adsorb onto its surface, creating a conditioning protein film that functions as a link between the implant and adhering cells. Depending on the nano-roughness of the surface, proteins will adsorb in different amounts, with different conformations and orientations, possibly affecting the subsequent attachment of cells to the surface. Thus, modifications of the surface nanotopography of an implant may prevent biomaterial-associated infections. Fibrinogen is of particular importance since it contains adhesion epitopes that are recognized by both eukaryotic and prokaryotic cells, and can therefore influence the adhesion of bacteria. The aim of this study was to model adsorption of fibrinogen to smooth or nanostructured silica surfaces in an attempt to further understand how surface nanotopography may affect the orientation of the adsorbed fibrinogen molecule. We used a coarse-grained model, where the main body of fibrinogen (visible in the crystal structure) was modeled as rigid and the flexible C-chains (not visible in the crystal structure) were modeled as completely disordered. We found that the elongated fibrinogen molecule preferably adsorbs in such a way that it protrudes further into solution on a nanostructured surface compared to a flat one. This implicates that the orientation on the flat surface increases its bio-availability.

Preparation and Characterization of Nanostructured Titania-coated Silica Microsphere Membranes with Simultaneous Photo-catalytic and Separation Applications for Water Treatment

Preparation and Characterization of Nanostructured Titania-coated Silica Microsphere Membranes with Simultaneous Photo-catalytic and Separation Applications for Water Treatment

Hydrophilic-Oleophobic Membranes Based on Hydrolysis Products of Methoxytrimethylsilane with Additions of Silica Particles

The authors have shown the possibility of obtaining hydrophilic-oleophobic membranes through the application of an oleophobizing compound to a membrane base presented by meshes from stainless steels 100, 200, and 400. The oleophobizing compound is methoxytrimethylsilane from whose hydrolysis oleophobic methyl groups and hydrophilic silanol ones develop which form the type of wettability of a membrane. It has been shown that adding nanostructured silica particles creates surface roughness with an enormous number of pores and channels, which considerably enhances the oleophobicity of synthesized membranes. The resulting membranes exhibit high oleophobicity to organic liquids, letting water pass through their structure. This is promising for their use in the sphere of low-cost gravity separation of water and organic liquids.

Microwave combustion synthesis of tin oxide-decorated silica nanostructure using rice husk template for supercapacitor applications

Supercapacitors are emerged as leading energy storage device and developing new electrode materials for supercapacitors has received much scientific interest from the researchers. In this study, we have synthesized tin oxide-decorated amorphous silica (SnO2@RH-SiO2) nanostructures using rice husk template as a silica source via simple microwave combustion method for supercapacitor applications. XRD, FT-IR, and EDX studies obviously characterize that silica is present in amorphous form along with crystalline SnO2 having a rutile tetragonal structure in the prepared SnO2@RH-SiO2 sample. Further, TEM observation indicates that prepared sample is consisting of amorphous silica nanospheres decorated with agglomerated tin oxide nanoparticles having size of 5–10 nm. Cyclic voltammetry and galvanostatic charge/discharge studies characterize the supercapacitive behavior of working electrode fabricated from prepared SnO2@RH-SiO2 nanostructure. The specific capacitances of SnO2@RH-SiO2 nanostructure are about 448, 330, 275, 240, 225, and 200 F/g with the current density value of 1, 2, 4, 6, 8, and 10 A/g, respectively. The presence SnO2 species in SnO2@RH-SiO2 nanostructure can provide reactive surfaces for the adsorption/desorption charges and it facilitates the charge storage at the surface of sample. The above results suggested that the prepared SnO2@RH-SiO2 nanostructure has potential application for making electrochemical supercapacitors.

Environmentally superior cleaning of diatom frustules using sono-Fenton process: Facile fabrication of nanoporous silica with homogeneous morphology and controlled size.

Existing techniques for the preparation of silica structures from diatom cells include cleaning of frustules through baking at high temperature and oxidant cleaning using concentrated sulfuric acid, hydrogen peroxide, nitric acid, or sodium dodecyl sulfate (SDS)/ethylenediaminetetraacetic acid (EDTA). In this study, sono-Fenton (SF) process was examined to prepare nanoporous silica through cleaning diatom frustules, while preserving their structural features. Single colonies of Cyclotella sp. were cultivated in batch mode f/2-enriched seawater. Combination of Fenton process with ultrasonication was found to be more efficient than the sum of individual processes in the removal of organic compounds from Cyclotella sp. structure. The optimized amounts of operational parameters were determined as suspension pH of 3, diatom cell density of 4.8×105 cell mL-1, H2O2 concentration of 60mM, Fe2+ concentration of 15mM, ultrasound irradiation power of 400W and the temperature of 45°C. The results of energy-dispersive X-ray spectroscopy (EDX) and thermal gravimetry (TG) analyses proved that organic materials covering the cell wall were significantly removed from the frustules through SF process. Scanning electron microscopy (SEM) images showed that after SF treatment, silica nanostructures were produced having uniform pores less than 15nm in diameter. N2 adsorption-desorption isotherms demonstrated that almost non-porous structure of diatom frustules became mesoporous during removing the organic matrix. Lipids, amino acids, carbohydrates and organic acids or their oxidized products were identified using GC-MS analysis as the main organic compounds released from diatom cells to the solution after SF treatment. Treated frustules exhibited adsorption capability of 91.2mg/g for Methylene Blue, which was almost 2.5 times higher than that of untreated frustules (34.8mg/g).

Silica Nanodepletors: Targeting and Clearing Alzheimer's β‐Amyloid Plaques

AbstractAbnormal accumulation of β‐amyloid (Aβ) peptide aggregates in the brain is a major hallmark of Alzheimer's disease (AD). Aβ aggregates interfere with neuronal communications, ultimately causing neuronal damage and brain atrophy. Much effort has been made to develop AD treatments that suppress Aβ aggregate formation, thereby attenuating Aβ‐induced neurotoxicity. Here, the design of Aβ nanodepletors consisting of ultralarge mesoporous silica nanostructures and anti‐Aβ single‐chain variable fragments, with the goal of targeting and eliminating aggregative Aβ monomers, is reported. The Aβ nanodepletors impart a notable decline in Aβ aggregate formation, resulting in significant mitigation of Aβ‐induced neurotoxicity in vitro. Furthermore, stereotaxic injections of Aβ nanodepletors into the brain of an AD mouse model system successfully suppress Aβ plaque formation in vivo up to ≈30%, suggesting that Aβ nanodepletors can serve as a promising antiamylodoisis material.

The influence of amine-functionalized SiO2 nanostructures upon nanofiltration membranes

The addition of nanostructures to nanofiltration (NF) membranes is a strategy commonly used to improve certain of membranes properties. The functionalization of these nanostructures can be used to modify some of their characteristics. Thus, silica nanostructures (SiO2 NSs) amine-functionalized with (3-aminopropyl)trimethoxysilane (APTMS) (SiO2 NS@1) and with 3-[2-(2-aminoethylamino)ethylamino]-propyltrimethoxysilane (AEAEAPTMS) (SiO2 NS@3) were incorporated into NF membranes. These membranes were prepared with polysulfone (PSU), as a support layer, and a thin film comprised of polydopamine (PDA) and polyethyleneimine (PEI). Four different membrane compositions were prepared: M0 (PSU/PDA/PEI), MS (PSU/PDA/PEI+SiO2 NS), M1 (PSU/PDA/PEI+SiO2 NS@1) and M3 (PSU/PDA/PEI+SiO2 NS@3). Morphology, topography, chemical structure, hydrophilicity, flux and rejection of MgCl2 and NaCl were evaluated. Membrane leaching was performed to investigate the possibility of SiO2 NSs release and the ability to impart toxicity to the liquid medium. There was an improvement in the membranes properties, especially when amine-functionalized materials were incorporated. M1 provided the highest permeate flux and salt rejection values. Leaching assays resulted in low Si release from the membranes and the leachates were not toxic to Daphnia magna. Therefore, the addition of amine-functionalized SiO2 NSs in NF membranes can result in better performance and in this study no toxicity was observed to the organism tested.

Preparation and characterisation of silica-based nanoparticles for cisplatin release on cancer brain cells.

In the present work, the preparation, characterisation, and efficiency of two different silica nanostructures as release vehicles of Cisplatin are reported. The 1-hexadeciltrimethyl-ammonium bromide templating agent was used to obtain mesoporous silica nanoparticles which were later loaded with Cisplatin. While sol-gel silica was very fast prepared using an excess of acetic acid during the hydrolysis-condensation reactions of tetraethylorthosilicate and at the same time the Cisplatin was added. Several physicochemical techniques including spectroscopies, electronic microscopy, X-ray diffraction, N2 adsorption-desorption were used to characterise the silica nanostructures. An in vitro Cisplatin release test was carried out using artificial cerebrospinal fluid. Finally, the toxicity of all silica nanostructures was tested using the C6 cancer cell line. The spectroscopic results showed the suitable stabilisation of Cisplatin into the two different silica nanostructures. A large surface area was obtained for the mesoporous silica nanoparticles, while low areas were obtained in the silica nanoparticles. Cisplatin was released faster from mesoporous silica channels than from inside of aggregates nanoparticles silica. Cisplatin alone, as well as, cisplatin released from both silica nanostructures exerted a toxic effect on cancer cells. In contrast, both silica structures without the drug did not exert any toxic effect.

Fused-silica capillary internally modified with nanostructured octadecyl silica for dynamic in-tube solid-phase microextraction of polycyclic aromatic hydrocarbons from aqueous media

The internal surface of a fused-silica capillary was made much more porous, more adsorptive and resistant to chemical and mechanical stresses by chemical coating using nanostructured octadecyl silica particles. The modification process was conducted using a simple and green nucleosynthesis procedure. The internally modified capillary was used as an in-tube solid-phase microextraction (IT-SPME) device for the extraction and preconcentration of ultratrace levels of polycyclic aromatic hydrocarbons (PAHs) in aqueous samples, followed by determination using gas chromatography-flame ionization detection (GC-FID) system. Morphology and structure of the sorbent was characterized by FT-IR, SEM and energy dispersive X-ray techniques. The effects of a range of experimental variables on the efficiency of the IT-SPME-GC-FID method were evaluated and optimized. Under the optimal conditions, good linearity (R2 > 0.99) was obtained for the calibration graphs over the range of 1–4000 ng mL−1. Detection limits were 0.22–0.47 ng mL−1 and relative standard deviations were obtained in the range 4.4–10.3%. Recoveries of the spiked samples were found to be 78.7–103.5%. The proposed IT-SPME-GC-FID strategy was applied successfully for the analysis of PAHs in real water samples. The results demonstrated good analytical performances, compared with those reported elsewhere for the sampling and quantification of PAHs in aqueous media.

Fabrication of Biogenic Silica Nanostructures from Sorghum bicolor Leaves for Food Industry Applications

Due to the large production of sorghum, the generation of associated agricultural residues, which contain high contents of silica, is inevitable. Also, these agricultural residues are not utilizing properly and it creates environmental pollution. Thus, we are utilizing the sorghum residues as a silica precursor to fabricating biogenic silica nanostructures using sequential processes. The physicochemical features of the synthesized BSNs, i.e., amorphous nature, surface functional groups, thermal stability, structure, and morphology, were analyzed using X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis, scanning electron microscopy, and transmission electron microscopy. The cytotoxic properties of the S. bicolor-derived BSNs were assessed using human colon carcinoma cells as an in vitro model and cell-based assays, including an 3–4,5-dimethylthiazol-2,5-diphenyltetrazolium bromide (MTT) assay, and acridine orange/ethidium bromide staining (AO/EB). The silica content of S. bicolor leaves was around 9.34%. We observed peaks at 1089 cm−1 and 801 cm−1 in the FTIR spectra of BSNs that corresponded to asymmetric, symmetric, and bending vibrations of O–Si–O. The BSNs had spherical morphology with diameters of 30–90 nm and an amorphous nature. The cytotoxic analysis suggested that BSNs do not induce cell death in colon carcinoma cells. Overall, the results suggested that BSNs exhibit good compatibility in colon cells, and may be applicable as an anti-caking agent in the food sector.