Surface-Enhanced Infrared Spectral Investigations of 2,3-Bis(chloromethyl)anthracene-1,4,9,10-tetraone on Copper Nanoparticles

ABSTRACT

Surface-enhanced infrared (IR) absorption spectroscopic technique has been employed to investigate the orientation of 2,3-bis(chloromethyl)anthracene-1,4,9,10-tetraone (BCMAT) on copper nanoparticles (NPs). Copper NPs have been prepared by the chemical reduction method. The observed ring stretching modes show higher downshifts, broader bandwidths, and higher enhancement. The observed features in out-of-plane and in-plane CH deformation modes indicate that the BCMAT molecules may be adsorbed in a “flat-on” orientation on the copper NPs. The observed lower enhancement factor of the in-plane C?O deformation mode and C?O stretching mode and the higher enhancement factor of out-of-plane C?O deformation mode elucidate that the BCMAT molecules are adsorbed on the copper NPs in a “flat-on” orientation. All these observations show that BCMAT is adsorbed on copper NPs through the π-anthraquinone ring system in a “flat-on” orientation.     

Stimuli-sensitive nanoparticles for multiple anti-HIV microbicides

This study is aimed to develop and evaluate an advanced intravaginal formulation for the delivery of multiple anti-HIV microbicides. Novel stimuli-sensitive nanoparticles (NPs) which protected the encapsulated drugs from being degraded in acidic pH conditions were made of Eudragit S-100^® (ES100^®), a pH-sensitive polymer. ES100^® NPs were prepared using the quasi-emulsion solvent diffusion technique and loaded with two microbicides namely Tenofovir (TNF) and Etravirine (ETV). The effects of various fabrication parameters on the formulation properties were evaluated for the optimization of ES100^® NPs. The morphology of the ES100^® NPs was examined by scanning electron microscopy. The cytotoxicity of NPs containing microbicides individually or in a combination was assessed using cell viability and trans-epithelial electrical resistance (TEER) measurements. The cellular uptake rates of the model microbicides by human vaginal epithelial cells, VK2 E6/E7 cells, were evaluated using confocal microscopy and florescence-assisted cell sorting technique. ES100^® NPs had a spherical shape, smooth surface, and uniform texture with a little aggregation. The average particle size for NPs loaded with TNF ranged from 125 to 230 nm, whereas those for ETV-loaded NPs ranged from 160 to 280 nm. ES100^® NPs had zeta potential in the range of ?5 to ?10 mV. In-vitro release studies displayed the potential benefits of ES100^® NPs in retaining and protecting the loaded microbicides at vaginal pH (acidic), but immediately releasing them as the pH changes to neutral or 7.4 (physiological pH). Cell viability studies demonstrated that ES100^® NPs did not exert any cytotoxicity individually or in a combination of both microbicides. TEER measurements confirmed that ES100^® NPs loaded with TNF and ETV did not cause any changes in the barrier integrity of VK2 E6/E7 cell monolayer. The cellular uptake study revealed that ES100^® NPs were taken by vaginal epithelial cells through the endocytosis process and that the uptake rate of the model microbicides loaded in nanoparticles was greater than that in the solution. The ES100^® NPs whose degradation rates are dependent on environmental pH would serve as an efficient platform for targeted delivery of multiple microbicides to protect women from sexually transmitted diseases including HIV-1 infection.     

Pressure unfolding facilitates the formation of temperature gels

Abstract

The formation of protein aggregates after pressure treatment was investigated by Fourier Transform Infrared Spectroscopy (FTIR). The results show that the pressure unfolded protein ends in a conformation, after the release of the pressure, which has an increased tendency to aggregate, even at temperatures lower than the denaturation temperature of the untreated protein. After pressure pretreatment the infrared spectrum shows the same intermolecular antiparallel β-structure features as observed after a temperature treatment that gives rise to protein gelation. on the other hand, this structure can be destabilized by applying moderate pressures, which are significantly lower than the corresponding denaturation pressure.     

Nanoparticle transport in water-unsaturated porous media: effects of solution ionic strength and flow rate

This paper presents the influence of ionic strength and flow on nanoparticle (NP) retention rate in an unsaturated calcareous medium, originating from a heterogeneous glaciofluvial deposit of the region of Lyon (France). Laboratory columns 10 cm in diameter and 30 cm in length were used. Silica nanoparticles (Au-SiO₂-FluoNPs), with hydrodynamic diameter ranging from 50 to 60 nm and labeled with fluorescein derivatives, were used to simulate particle transport, and bromide was used to characterize flow. Three flow rates and five different ionic strengths were tested. The transfer model based on fractionation of water into mobile and immobile fractions was coupled with the attachment/detachment model to fit NPs breakthrough curves. The results show that increasing flow velocity induces a decrease in nanoparticle retention, probably as the result of several physical but also geochemical factors. The results show that NPs retention increases with ionic strength. However, an inversion of retention occurs for ionic strength >5.10^?2 M, which has been scarcely observed in previous studies. The measure of zeta potential and DLVO calculations show that NPs may sorb on both solid-water and air-water interfaces. NPs size distribution shows the potential for nanoparticle agglomeration mostly at low pH, leading to entrapment in the soil pores. These mechanisms are highly sensitive to both hydrodynamic and geochemical conditions, which explains their high sensitivity to flow rates and ionic strength.     

Adsorption and desorption of Ca and PO4 species from SBFs on RF-sputtered calcium phosphate thin films

RF magnetron sputtering of calcium phosphate (CaP) coatings is a promising technique to apply thin bioactive films on bulk implant materials. In this paper the properties of the interface between RF sputtered coatings and simulated body fluids (SBFs) are related to the ability to form CaP crystals on the coating surface. Two types of coatings were compared: coatings with a low Ca over P ratio (∼0.8; CaP_low), which remain inert when immersed in SBF₂ (i.e. SBF with twice the Ca and PO₄ concentrations), and coatings with a high Ca over P ratio (1.6; CaP_high), which show the formation of CaP crystals on their surface within 2 h. Low energy ion scattering (LEIS) and radioactive labeling of the SBFs combined with liquid scintillation counting (LSC) allowed us to study very accurately the composition of the adsorbates of both coating groups after 10 min of immersion in SBF₂. For the adsorbate on CaP_high and CaP_low coatings coverages were found consistent with ionic adsorption and Ca/P ratios of 1.24 ± 0.02 and 2.17 ± 0.10, respectively. Adsorption was found to be reversible over the studied immersion period. After an induction period of 40 min a CaP precipitate started to form on the CaP_high coatings with a Ca/P ratio of 1.30 ± 0.02. Further, no significant desorption of coating species was observed during this induction period.     

Study of interactions of 2-benzamido-4-methylpentanoic acid-2-cyclohexyl carboxamide with BSA: Gel exclusion chromatography and molecular modeling techniques

Plasma protein in blood play an important role in transportation of drug. So it is important to know the binding of drug with plasma protein. In this study we successfully observed the interaction of 2-benzamido-4-methylpentanoic acid-2-cyclohexyl carboxamide ligand (2-bmca) with Bovine serum albumin (BSA) using gel exclusion chromatographic technique at different pH. Absorbance value for collected fraction was measured on UV-vis Spectrophotometer. Differences in the absorbance value of collected fraction give the specific binding of interacting species with BSA. Interacting study shows that ligand (L) bounds to the BSA more significantly at pH 3 than at pH 4 and 5, which shows binding is more at acidic pH. Scatchard analysis gives the association constants (K _f) and the saturation value (n) for ligand(L) with BSA. Molecular modeling study gives the efficient energy value–231.16 which confirms the binding of ligand (L) with BSA.     

High pressure effects on myofibrillar proteins

Abstract

Myofibrillar proteins were extracted from post rigor bovine meat with a potassium phosphate/potassium chloride buffer. Viscoelastic properties of myofibrillar properties were studied in a 0.6MKCl buffer, at pH = 6, used in an oscillating mode. Enthalpy patterns were determined with a differential scanning calorimeter. SDS PAGE was performed.

Results show that high pressure processing denatures myofibrillar proteins, which result in a decrease of myofibrillar protein extractability. Moreover, the viscoelastic properties of myofibrillar extracts are modified by a preliminary high-pressure treatment of meat. The storage modulus (G′) versus temperature graph presents an intermediate peak; the height of this peak and the final value (90°C) are dependant on the level of pressure.

Finally, enthalpy and electrophoresis patterns allow us to understand myofibrillar protein modifications induced by high hydrostatic pressure processing of meat.     

High stability of the crystalline configuration of Au nanoparticles embedded in silica under ion and electron irradiation

Au nanoparticles (NPs) with a size in the 2–12 nm range have been grown in silica by 2 MeV Au-ion implantation and a subsequent thermal annealing in air. The as-prepared Au NPs were irradiated with 10 MeV Si ions elongating some of them. From transmission electron microscopy in Z-contrast mode, we observed a narrow size distribution of the minor axis of the deformed NPs, which presents its higher frequency around 6–7 nm and have a saturation about 9 nm. This final result agrees well with the diameter of the track formed by Si ions of 10 MeV in silica, supporting the thermal spike model, which would explain the deformation of the NPs. In this model, the NP melts and creeps along the ion track. Our results show that the NP crystallization is in the fcc structure. On the other hand, a 200 keV electron irradiation provoked roundness on the previously elongated nanoparticles. This effect was observed in situ by high-resolution transmission electron microscopy, showing additionally that, during the roundness process, the fcc structure, as well as its crystalline orientation, remain unchanged. Thus, this study shows how Au NPs embedded in silica, within this size distribution, keep the fcc bulk structure under both ion and electron irradiations.     

Antibacterial Activity of Ciprofloxacin-Loaded Poly(lactic-co-glycolic acid)-Nanoparticles Against Staphylococcus aureus

The formation of bacterial biofilms on material surfaces is a recurrent problem in public health. Antibacterial nanoparticles (NPs) are promising because pathogens have not yet developed resistance mechanisms and encapsulation of the drug can protect it from the surrounding medium and improve pharmacokinetics. Biocompatible and biodegradable particles of various sizes (nano- and micro-scale) based on poly(lactic-co-glycolic acid) (PLGA) are elaborated using a simple and free toxic nanoprecipitation process. Particles are poly(ethylene glycol) (PEG)-ylated in order to reduce unwanted interactions with biological fluids, or loaded with the large spectrum antibiotic ciprofloxacin (CIP). NPs are studied against Staphylococcus aureus in planktonic and biofilm modes. Empty NPs with smallest size (60 nm) are able to totally eradicate planktonic culture after 24 h, even in the presence of serum proteins. CIP-loaded NPs present slightly lower antimicrobial activity against planktonic microorganisms compared with the free antibiotic, due to progressive release of CIP over time. In biofilm mode, CIP-loaded NPs show a very good antibiofilm activity, much better than free CIP, thanks to NPs penetration within the polymer matrix and a consequent release of the antibiotic close to the embedded bacteria. The present results open the way for widespread applications of PLGA-NPs in the pharmaceutical or medical fields.     

The Competitive Dynamic Binding of Some Blood Proteins Adsorbed on Gold Nanoparticles

Nanoparticle (NP) surfaces are modified immediately by the adsorption of proteins when injected into human blood, leading to the formation of a protein corona. The protein‐coated NPs may be recognized by living cells. Furthermore, the adsorption of serum proteins is a continuous competitive dynamic process that is the key to exploring the bioapplication and biosafety of NPs. In this study, the competitive dynamic adsorption of some serum proteins on gold nanoparticles (AuNPs) is investigated by fluorescence emission, dynamic light scattering, and sodium dodecyl sulfate‐polyacrylamide gel electrophoresis. Serum proteins with different AuNPs binding affinities are used to address the competitive dynamic process of protein‐AuNP interactions in vitro. The results show that more abundant serum proteins, such as human serum albumin, adsorb on AuNPs first, and then the higher binding affinity and lower concentration serum proteins, such as fibrinogen (FIB), replace the abundant and lower binding affinity serum proteins. However, the lower binding affinity serum proteins, such as hemoglobin, do not replace the higher binding affinity proteins from the protein‐AuNP conjugates. During the dynamic exchange process, the larger the binding affinities difference between two proteins, the faster the exchange rate. This dynamic exchange process usually takes longer in inner protein‐AuNP conjugates (hard corona) than the external surface of protein‐AuNP conjugates (soft corona).     

Two‐Photon Imaging of a Cellular Line Using Organic Fluorescent Nanoparticles Synthesized by Laser Ablation

A comparative study of the optical properties of organic fluorescent nanoparticles fabricated by laser ablation (NPs‐LA), reprecipitation (NPs‐RP), and microemulsion (NPs‐ME) methods is presented. These nanoparticles contain a fluorene‐based p‐conjugated molecule (BT2). Distinctive electronic transitions are observed in samples due to the specific way in which the molecule BT2 is assembled in each type of nanoparticles; for instance, transitions involved in absorption and emission spectra of NPs‐LA result in blueshifting with respect to the molecular solution of BT2, whereas redshifting is observed in NPs‐RP and NPs‐ME. Further, the results show that under infrared excitation, the aqueous suspensions of NPs‐LA exhibit the highest fluorescence induced by two‐photon absorption (≈790 GM at 740 nm), as well as the best photostability, compared with aqueous suspensions of NPs‐RP and NPs‐ME. The nanoparticles synthetized by the three aforementioned methods are employed as exogenous agents for the visualization of human cervical cancer cell line (HeLa) using confocal and two‐photon microscopy. Under similar experimental conditions, it is found that microscopy images of the best quality are obtained with NPs‐LA. These results show that laser ablation is a suitable technique for the fabrication of organic fluorescent nanoparticles used as contrast agents for in vitro fluorescence microscopy.     

Core–Shell Bi2Se3@mSiO2‐PEG as a Multifunctional Drug‐Delivery Nanoplatform for Synergistic Thermo‐Chemotherapy with Infrared Thermal Imaging of Cancer Cells

Thermo‐chemotherapy combining photothermal therapy (PTT) with chemotherapy has become a potent approach for antitumor treatment. In this study, a multifunctional drug‐delivery nanoplatform based on polyethylene glycol (PEG)‐modified mesoporous silica‐coated bismuth selenide nanoparticles (referred to as Bi₂Se₃@mSiO₂‐PEG NPs) is developed for synergistic PTT and chemotherapy with infrared thermal (IRT) imaging of cancer cells. The product shows no/low cytotoxicity, strong near‐infrared (NIR) optical absorption, high photothermal conversion capacity, and stability. Utilizing the prominent photothermal effect, high‐contrast IRT imaging and efficient photothermal killing effect on cancer cells are achieved upon NIR laser irradiation. Moreover, the successful mesoporous silica coating of the Bi₂Se₃@mSiO₂‐PEG NPs cannot only largely improve the stability but also endow the NPs high drug loading capacity. As a proof‐of‐concept model, doxorubicin (DOX) is successfully loaded into the NPs with rather high loading capacity (≈50.0%) via the nanoprecipitation method. It is found that the DOX‐loaded NPs exhibit a bimodal on‐demand pH‐ and NIR‐responsive drug release property, and can realize effective intracellular drug delivery for chemotherapy. The synergistic thermo‐chemotherapy results in a significantly higher antitumor efficacy than either PTT or chemotherapy alone. The work reveals the great potential of such core–shell NPs as a multifunctional drug‐delivery nanosystem for thermo‐chemotherapy.     

In vitro investigation of anodization and CaP deposited titanium surface using MG63 osteoblast-like cells

The aim of the present study was to investigate surface characteristics in four different titanium surfaces (AN: anodized at 270 V; AN-CaP: anodic oxidation and CaP deposited; SLA: sandblasted and acid etched; MA: machined) and to evaluate biological behaviors such as cell adhesion, cell proliferation, cytoskeletal organization, and osteogenic protein expression of MG63 osteoblast-like cells at the early stage. Surface analysis was performed using scanning electron microscopy, thin-film X-ray diffractometry, and a confocal laser scanning microscope. In order to evaluate cellular responses, MG63 osteoblast-like cells were used. The cell viability was evaluated by MTT assay. Immunofluorescent analyses of actin, type I collagen, osteonectin and osteocalcin were performed. The anodized and CaP deposited specimen showed homogeneously distributed CaP particles around micropores and exhibited anatase type oxides, titanium, and HA crystalline structures. This experiment suggests that CaP particles on the anodic oxidation surface affect cellular attachment and spreading. When designing an in vitro biological study for CaP coated titanium, it must be taken into account that preincubation in medium prior to cell seeding and the cell culture medium may affect the CaP coatings. All these observations illustrate the importance of the experimental conditions and the physicochemical parameters of the CaP coating.It is considered that further evaluations such as long-term in vitro cellular assays and in vivo experiments should be necessary to figure out the effect of CaP deposition to biological responses.     

A facile pollutant-free approach toward a series of nutritionally effective calcium phosphate nanomaterials for food and drink additives

Micronutrient malnutrition is widespread and constitutes one of the main nutritional problems worldwide. Vitamins, amino acids, carbohydrates and Ca-phosphate (CaP) minerals are important to human health and disease prevention. Herein we developed a simple wet-chemical method to prepare multinary nutrients-containing CaP nanomaterials in diluted apple, orange, and grape juices. The scanning electron microscopy observation shows that these nanomaterials are short plate-like CaP nanocrystals of ~500 nm in length. The X-ray photoelectron spectroscopy, nitrogen adsorption, thermogravimetric analyses confirm the different specific surface area and organic nutrient contents. The Fourier transform infrared and X-ray diffraction analyses indicate there exist similar organic groups (i.e., COO⁻, HN-CO) but different CaP species in the precipitates. The dissolution test in vitro simulated stomach juice pH condition indicates that these inorganic–organic nanohybrid materials are multidoped by micronutrients (such as Zn, Sr, Mg, K, vitamin c) and can be readily dissolved in the weak acidic aqueous solutions. This highly efficient utilization of fruit juice to produce CaP-based micronutrient composites may minimize the adverse side effect, so that the nanomaterials are promising as functional food/drink additives. Thus, this novel approach is environmentally and biologically friendly to produce edible nutrients while production cost is attained.     

Selective Targeting of Lymphoma Cells by Monoclonal Antibody Grafted onto Zwitterionic-Functionalized Nanoparticles

Nanomedicine is considered a promising alternative to improve cancer diagnosis and treatment. Particularly, the use of nanoparticles (NPs) has enabled the encapsulation of highly toxic anticancer drugs, facilitated ultimate targeting, and allowed tailoring of drug delivery. However, when in biological fluids, these NPs are coated by proteins which hide the targeting moieties and suppress the engineered biological outcome. Herein, how the Ki-1 monoclonal antibody (mAb) can preserve its targetability through grafting on the surface of zwitterionic-functionalized nanoparticles, is unveiled. Zwitterions, known for their stealth ability, are used to minimize unspecific NPs protein adsorption and consequently maintain mAb functionality. In this work, Ki-1 mAb is used as it recognizes TNFRSF8 (CD30⁺) transmembrane protein overexpressed on CD30⁺ lymphoma cells such as L540 cells. While nonfunctionalized NPs show negligible toxic effects toward L540 cells, the Ki-1-functionalized structure demonstrates cytotoxicity, since they undergo cellular uptake, suggesting a receptor-mediated internalization. This dual-functionalization strategy provides a promising multifunctional nanoplatform toward future personalized medicine applications, minimizing unspecific protein adsorption on NPs and ensuring selective cancer cell targeting.     

Effect of serum proteins on polystyrene nanoparticle uptake and intracellular trafficking in endothelial cells

The physico-chemical properties of nanoparticles (NPs), such as small dimensions, surface charge and surface functionalization, control their capability to interact with cells and, in particular, with sub-cellular components. This interaction can be also influenced by the adsorption of molecules present in biological fluids, like blood, on NP surface. Here, we analysed the effect of serum proteins on 49 and 100 nm red fluorescent polystyrene NP uptake in porcine aortic endothelial (PAE) cells, as a model for vascular transport. To this aim, NP uptake kinetic, endocytic pathway and intracellular trafficking were studied by monitoring NPs inside cells through confocal microscopy and multiple particle tracking (MPT). We demonstrated that NPs are rapidly internalized by cells in serum-free (SF) medium, according to a saturation kinetic. Conversely, in 10% foetal bovine serum-enriched (SE) medium, NP uptake rate results drastically reduced. Moreover, NP internalization depends on an active endocytic mechanism that does not involve clathrin- and caveolae-mediated vesicular transport, in both SE and SF media. Furthermore, MPT data indicate that NP intracellular trafficking is unaffected by protein presence. Indeed, approximately 50–60% of internalized NPs is characterized by a sub-diffusive behaviour, whereas the remaining fraction shows an active motion. These findings demonstrate that the unspecific protein adsorption on NP surface can affect cellular uptake in terms of internalization kinetics, but it is not effective in controlling active and cellular-mediated uptake mechanisms of NPs and their intracellular routes.     

Spectroscopic analysis of the riboflavin—serum albumins interaction on silver nanoparticles

Metallic nanoparticles (NPs) supported on oxides thin films are commonly used as model catalysts for studies of heterogeneous catalysis. Several 4d and 5d metal NPs (for example, Pd, Pt and Au) grown on alumina, ceria and titania have shown strong metal support interaction (SMSI), for instance the encapsulation of the NPs by the oxide. The SMSI plays an important role in catalysis and is very dependent on the support oxide used. The present work investigates the growth mechanism and atomic structure of Rh NPs supported on epitaxial magnetite Fe₃O₄(111) ultrathin films prepared on Pd(111) using the Molecular Beam Epitaxy (MBE) technique. The iron oxide and the Rh NPs were characterized using X-ray photoelectron spectroscopy (XPS), low-energy electron diffraction and photoelectron diffraction (PED). The combined XPS and PED results indicate that Rh NPs are metallic, cover approximately 20 % of the iron oxide surface and show height distribution ranging 3–5 ML (monolayers) with essentially a bulk fcc structure.     

In Vitro Evaluation of Non‐Protein Adsorbing Breast Cancer Theranostics Based on 19F‐Polymer Containing Nanoparticles

Eight fluorinated nanoparticles (NPs) are synthesized, loaded with doxorubicin (DOX), and evaluated as theranostic delivery platforms to breast cancer cells. The multifunctional NPs are formed by self‐assembly of either linear or star‐shaped amphiphilic block copolymers, with fluorinated segments incorporated in the hydrophilic corona of the carrier. The sizes of the NPs confirm that small circular NPs are formed. The release kinetics data of the particles reveals clear hydrophobic core dependence, with longer sustained release from particles with larger hydrophobic cores, suggesting that the DOX release from these carriers can be tailored. Viability assays and flow cytometry evaluation of the ratios of apoptosis/necrosis indicate that the materials are non‐toxic to breast cancer cells before DOX loading; however, they are very efficient, similar to free DOX, at killing cancer cells after drug encapsulation. Both flow cytometry and confocal microscopy confirm the cellular uptake of NPs and DOX‐NPs into breast cancer cells, and in vitro ¹⁹F‐MRI measurement shows that the fluorinated NPs have strong imaging signals, qualifying them as a potential in vivo contrast agent for ¹⁹F‐MRI.     

Protein‐Affinitive Polydopamine Nanoparticles as an Efficient Surface Modification Strategy for Versatile Porous Scaffolds Enhancing Tissue Regeneration

Porous scaffolds for tissue regeneration are often functionalized with extracellular matrix proteins to enhance surface/cell interactions and tissue regeneration. However, continuous coatings produced by commonly used surface modification strategies may preclude cells from contacting and sensing the chemical and physical cues of the scaffold. Here, it is shown that polydopamine nanoparticles (PDA‐NPs) tightly adhere on various scaffolds to form nanostructures, and the coverage can be finely tuned. Furthermore, the PDA‐NPs have good affinity to a variety of proteins and peptides. Thus, the PDA‐NPs act as an anchor to immobilize signal biomolecules on scaffolds, and consequently promote cell activity and tissue regeneration. β‐Tricalcium phosphate (TCP) scaffolds decorated with PDA‐NPs demonstrate excellent osteoinductivity and bone‐regeneration performance due to the protein affinity of PDA‐NPs and the intrinsic bioactive characteristics of TCP scaffolds. In summary, PDA‐NPs with excellent affinity for protein adhesion represent a versatile platform to modify porous scaffolds while not compromising the biological functions of the scaffolds, and might have potential applications in tissue regeneration.     

Protein extraction and cytotoxicity abilities of colloidal gold-coated silica hybrid nanoparticles

Monodisperse non-hybrid silica and hybrid colloidal silica of ≤?200 nm decorated with small Au nanoparticles (NPs) were synthesized in a simple single-step method. Non-hybrid silica NPs were synthesized in the absence and presence of different twin tail cationic surfactants, while tiny Au NPs were grown under in situ reaction conditions on non-hybrid silica synthesized previously by using cationic dextran. Bio-applicability and cytotoxicity of both hybrid as well as non-hybrid silica NPs were tested by using them for the extraction of protein fractions from complex aqueous protein solutions and treating them with blood cells, respectively. Both non-hybrid and hybrid silica NPs demonstrate excellent ability to extract proteins fractions predominantly of relatively low molecular masses, i.e., ~ 80 kDa. Extraction preferences between both kinds of silica became prominent when predominantly hydrophobic proteins such zein and rice proteins were used rather than mainly polar protein like BSA. Applicability for more complex biological fluid like serum indicated the competitive extractions among strongly versus weakly bound proteins. With significant bearing in in vivo conditions, hybrid silica was potentially toxic towards the blood cells in comparison to non-hybrid silica. It stems from the collective interactions of silica as well as nanometallic surfaces of Au NPs to interact with the blood cells causing hemolysis and hence may not be the suitable vehicles for drug release in systemic circulation.

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