Controlled quercetin release from high-capacity-loading hyperbranched polyglycerol-functionalized graphene oxide

E-beam irradiation-induced synthesis of hydroxyethyl cellulose/(Cu2O-rGO)/BiVO4-based nanocomposite for photocatalytic remediation of wastewater under visible light

Using E-beam irradiation as an eco-friendly technique for initiation and crosslinking, a series of Hydroxyethyl Cellulose-poly vinyl alcohol copolymer hydrogels were synthesized as templates for cuprous oxide (Cu2O), reduced graphene oxide (rGO) and bismuth vanadate (BiVO4) nanoparticles to be used as nanocomposites photocatalysts for methylene blue (MB) dye decolorization using visible light. Preparation conditions were optimized to ensure the construction of a good network architecture and therefore the highest gelation degree. For the preparation of (Cu2O@rGO)/BiVO4 nanocomposites, a series of rGO was decorated by Cu2O using the precipitation method, followed by mixing with BiVO4 which was synthesized hydrothermally. (EDX), (XRD), (TEM), and (SEM) were used for nanoparticle characterization. The thermal characteristics of the fabricated nanocomposites were evaluated using thermal gravimetric analysis. The presence of rGO enhanced the decolorization efficiency of MB about 20 % higher than that of (HEC-PVA)/Cu2O which achieves only (59 %) decolorization efficiency. After the addition of BiVO4 NPs, the decolorization efficiency increased to reach 90 % after 150 min at pH 11 using a 10 ppm MB solution. The developed (HEC-PVA)/(Cu2O@rGO)/BiVO4 photocatalyst exhibits efficient reusability for 5 cycles. Treated dyed water shows a germination index (GI) of 82 % suggesting its suitability for irrigation of playgrounds and gardens.

Application of Nanoparticles for Efficient Delivery of Quercetin in Cancer Cells

Quercetin (Qu, 3,5,7,3', 4'-pentahydroxyflavanone) is a natural polyphenol compound abundantly found in health food or plant-based products. In recent decades, Qu has gained significant attention in the food, cosmetic, and pharmaceutic industries owning to its wide beneficial therapeutic properties such as antioxidant, anti-inflammatory and anticancer activities. Despite the favorable roles of Qu in cancer therapy due to its numerous impacts on the cell signaling axis, its poor chemical stability and bioavailability, low aqueous solubility as well as short biological half-life have limited its clinical application. Recently, drug delivery systems based on nanotechnology have been developed to overcome such limitations and enhance the Qu biodistribution following administration. Several investigations have indicated that the nano-formulation of Qu enjoys more remarkable anticancer effects than its free form. Furthermore, incorporating Qu in various nano-delivery systems improved its sustained release and stability, extended its circulation time, enhanced its accumulation at target sites, and increased its therapeutic efficiency. The purpose of this study was to provide a comprehensive review of the anticancer properties of various Qu nano-formulation to augment their effects on different malignancies. Various targeting strategies for improving Qu delivery, including nanoliposomes, lipids, polymeric, micelle, and inorganic nanoparticle NPs, have been discussed in this review. The results of the current study illustrated that a combination of appropriate nano encapsulation approaches with tumor-oriented targeting delivery might lead to establishing QU nanoparticles that can be a promising technique for cancer treatment.

Graphene oxide nanoarchitectures in cancer therapy: Drug and gene delivery, phototherapy, immunotherapy, and vaccine development

The latest advancements in oncology involves the creation of multifunctional nanostructures. The integration of nanoparticles into the realm of cancer therapy has brought about a transformative shift, revolutionizing the approach to addressing existing challenges and limitations in tumor elimination. This is particularly crucial in combating the emergence of resistance, which has significantly undermined the effectiveness of treatments like chemotherapy and radiotherapy. GO stands as a carbon-derived nanoparticle that is increasingly finding utility across diverse domains, notably in the realm of biomedicine. The utilization of GO nanostructures holds promise in the arena of oncology, enabling precise transportation of drugs and genetic material to targeted sites. GO nanomaterials offer the opportunity to enhance the pharmacokinetic behavior and bioavailability of drugs, with documented instances of these nanocarriers elevating drug accumulation at the tumor location. The GO nanostructures encapsulate genes, shielding them from degradation and facilitating their uptake within cancer cells, thereby promoting efficient gene silencing. The capability of GO to facilitate phototherapy has led to notable advancements in reducing tumor progression. By PDT and PTT combination, GO nanomaterials hold the capacity to diminish tumorigenesis. GO nanomaterials have the potential to trigger both cellular and innate immunity, making them promising contenders for vaccine development. Additionally, types of GO nanoparticles that respond to specific stimuli have been applied in cancer eradication, as well as for the purpose of cancer detection and biomarker diagnosis. Endocytosis serves as the mechanism through which GO nanomaterials are internalized. Given these advantages, the utilization of GO nanomaterials for tumor elimination comes highly recommended.

Graphene oxide nanoarchitectures in cancer biology: Nano-modulators of autophagy and apoptosis

Nanotechnology is a growing field, with many potential biomedical applications of nanomedicine for the treatment of different diseases, particularly cancer, on the horizon. Graphene oxide (GO) nanoparticles can act as carbon-based nanocarriers with advantages such as a large surface area, good mechanical strength, and the capacity for surface modification. These nanostructures have been extensively used in cancer therapy for drug and gene delivery, photothermal therapy, overcoming chemotherapy resistance, and for imaging procedures. In the current review, we focus on the biological functions of GO nanoparticles as regulators of apoptosis and autophagy, the two major forms of programmed cell death. GO nanoparticles can either induce or inhibit autophagy in cancer cells, depending on the conditions. By stimulating autophagy, GO nanocarriers can promote the sensitivity of cancer cells to chemotherapy. However, by impairing autophagy flux, GO nanoparticles can reduce cell survival and enhance inflammation. Similarly, GO nanomaterials can increase ROS production and induce DNA damage, thereby sensitizing cancer cells to apoptosis. In vitro and in vivo experiments have investigated whether GO nanomaterials show any toxicity in major body organs, such as the brain, liver, spleen, and heart. Molecular pathways, such as ATG, MAPK, JNK, and Akt, can be regulated by GO nanomaterials, leading to effects on autophagy and apoptosis. These topics are discussed in this review to shed some lights towards the biomedical potential of GO nanoparticles and their biocompatibility, paving the way for their future application in clinical trials.

Organically surface engineered mesoporous silica nanoparticles control the release of quercetin by pH stimuli

Controlling the premature release of hydrophobic drugs like quercetin over physiological conditions remains a challenge motivating the development of smart and responsive drug carriers in recent years. This present work reported a surface modification of mesoporous silica nanoparticles (MSN) by a functional compound having both amines (as a positively charged group) and carboxylic (negatively charged group), namely 4-((2-aminoethyl)amino)-4-oxobut-2-enoic acid (AmEA) prepared via simple mechanochemistry approach. The impact of MSN surface modification on physical, textural, and morphological features was evaluated by TGA, N₂ adsorption-desorption, PSA-zeta, SEM, and TEM. The BET surface area of AmEA-modified MSN (MSN-AmEA) was found to be 858.41 m² g^-1 with a pore size of 2.69 nm which could accommodate a high concentration of quercetin 118% higher than MSN. In addition, the colloidal stability of MSN-AmEA was greatly improved as indicated by high zeta potential especially at pH 4 compared to MSN. In contrast to MSN, MSN-AmEA has better in controlling quercetin release triggered by pH, thanks to the presence of the functional groups that have a pose-sensitive interaction hence it may fully control the quercetin release, as elaborated by the DFT study. Therefore, the controlled release of quercetin over MSN-AmEA verified its capability of acting as a smart drug delivery system.

The Preparation of a Novel Hyperbranched Antifouling Material and Application in the Protection of Marine Concrete

Marine fouling on concrete has become one of the severest problems that damage the surface and even cause internal corrosion of marine concrete. Dissimilarly to the previous abuse of toxic antifoulants, developing hydrophobic waterborne antifouling materials could be regarded as one of the most environment-friendly and potential directions to protect marine concrete. However, the insufficient hydrophobicity, antifouling, and mechanical properties limit their application. Herein, we reported a series of hybrid coatings combining hyperbranched polyglycerol (HPG) decorated waterborne fluoro silicone polyurethane (H) and HPG-grafted graphene oxide (G-HPG) that improve the hydrophobicity, antifouling, and mechanical properties. The hybrid materials were modified by the hyperbranched polyglycerol synthesized based on the anionic-ring-opening reaction between glycerol and ethylene glycol or polyethylene glycol. Remarkably, the hydrophobicity (115.19°) and antifouling properties (BSA absorption of 2.33 μg/cm² and P. tricornutum attachment of 1.289 × 10⁴ CFU/cm²) of the materials could be developed by the modification of HPG with higher generation numbers and backbone molecular weights. Moreover, the mechanical properties negligibly decreased (tensile strength decreased from 11.29 MPa to 10.49 MPa, same pencil hardness and adhesion grade as H of 2H and grade 2). The results revealed that the HPG of higher generation numbers and backbone molecular weights could benefit materials with enhanced antifouling properties and hydrophobicity. The method of hyperbranched modification can be regarded as potentially effective in developing the durability and antifouling properties of marine antifouling materials.

Antimicrobial Activity of Graphene-Based Nanocomposites: Synthesis, Characterization, and Their Applications for Human Welfare

Graphene (GN)-related nanomaterials such as graphene oxide, reduced graphene oxide, quantum dots, etc., and their composites have attracted significant interest owing to their efficient antimicrobial properties and thus newer GN-based composites are being readily developed, characterized, and explored for clinical applications by scientists worldwide. The GN offers excellent surface properties, i.e., a large surface area, pH sensitivity, and significant biocompatibility with the biological system. In recent years, GN has found applications in tissue engineering owing to its impressive stiffness, mechanical strength, electrical conductivity, and the ability to innovate in two-dimensional (2D) and three-dimensional (3D) design. It also offers a photothermic effect that potentiates the targeted killing of cells via physicochemical interactions. It is generally synthesized by physical and chemical methods and is characterized by modern and sophisticated analytical techniques such as NMR, Raman spectroscopy, electron microscopy, etc. A lot of reports show the successful conjugation of GN with existing repurposed drugs, which improves their therapeutic efficacy against many microbial infections and also its potential application in drug delivery. Thus, in this review, the antimicrobial potentialities of GN-based nanomaterials, their synthesis, and their toxicities in biological systems are discussed.

Graphene oxide quantum dot-chitosan nanotheranostic platform as a pH-responsive carrier for improving curcumin uptake internalization: In vitro & in silico study

We herein fabricated a cancer nanotheranostics platform based on Graphene Oxide Quantum Dot-Chitosan-polyethylene glycol nanoconjugate (GOQD-CS-PEG), which were targeted with MUC-1 aptamer towards breast and colon tumors. The interaction between aptamer and MUC-1 receptor on the desired cells was investigated utilizing molecular docking. The process of curcumin release was investigated, as well as the potential of the produced nanocomposite in targeted drug delivery, specific detection, and photoluminescence imaging. The fluorescence intensity of GOQD-CS-PEG was reduced due to transferred energy between (cytosine-guanin) base pairs in the hairpin structure of the aptamer, resulting in an "on/off" photoluminescence bio-sensing. Interestingly, the integration of pH-responsive chitosan nanoparticles in the nanocomposite results in a smart nanocomposite capable of delivering more curcumin to desired tumor cells. When selectively binds to the MUC-1 receptor, the two strands of aptamer separate in acidic conditions, resulting in a sustained drug release and photoluminescence recovery. The cytotoxicity results also revealed that the nanocomposite was more toxic to MUC-1-overexpressed tumor cells than to negative control cell lines, confirming its selective targeting. As a result, the proposed nanocomposite could be used as an intelligent cancer nanotheranostic platform for tracing MUC-1-overexpressed tumor cells and targeting them with great efficiency and selectivity.

Carboxylated Graphene Oxide as a Nanocarrier for Drug Delivery of Quercetin as an Effective Anticancer Agent

Background:

Enhancing the therapeutic profile of hydrophobic drugs using the development of biocompatible drug delivery systems is an urgent need. Many types of research have been conducted on graphene derivatives owing to their unique characteristics.

Methods:

In this survey, QUER, a natural medicine, was loaded on carboxylated GO, and cytotoxicity assay and the uptake of QUER into prostate cancer cells (PC3) were evaluated.

Results:

The release behavior of QUER was temperature- and pH-sensitive. Although QUER was loaded with high efficiency, the released rate was low (23.25% at pH 5.5 and 42 °C). The toxicity and intensity of fluorescence in the FREE QUER were higher than the loaded form.

Conclusion:

High-capacity loading and controlled release of GO QUER can be recognized as a proper candidate in treating cancer.

Quercetin- and rutin-based nano-formulations for cancer treatment: A systematic review of improved efficacy and molecular mechanisms

BACKGROUND

Natural products, with incredible chemical diversity, have been widely studied for their antitumor potential. Quercetin (QU) and quercetin glycoside (rutin), both polyphenolic flavonoids, stick out amongst the natural products, through various studies. Rutin (RU) and its aglycone (QU) have various biological properties that include antioxidant, anti-inflammatory, and anticarcinogenic activities. However, several side effects have restricted the efficacy of these polyphenolic flavonoids, which makes it necessary to use new strategies involving low and pharmacological doses of QU and RU, either alone or in combination with other anticancer drugs.

PURPOSE

The aim of this study is to present a comprehensive and critical evaluation of the anticancer ability of different nano-formulations of RU and QU for improved treatment of various malignancies.

METHODS

Studies were recognized via systematic searches of ScienceDirect, PubMed, and Scopus databases. Eligibility checks were conducted based upon predefined selection criteria. Ninety articles were included in this study.

RESULTS

There was conclusive evidence for the association between anticancer activity and treatment with RU or QU. Furthermore, studies indicated that nano-formulations of RU and QU have greater anticancer activities in comparison to either agent alone, which leads to increased efficiency for treating cancer.

CONCLUSION

The results of this systematic review demonstrate the anticancer activities of nano-formulations of RU and QU and their molecular mechanisms through preclinical studies. This paper also attempts to contribute to further research by addressing the current limitations/challenges and proposing additional studies to realize the full potential of RU- and QU-based formulations for cancer treatment.

The Role of Graphene Oxide Nanocarriers in Treating Gliomas

Gliomas are the most common primary malignant tumors of the central nervous system, and their conventional treatment involves maximal safe surgical resection combined with radiotherapy and temozolomide chemotherapy; however, this treatment does not meet the requirements of patients in terms of survival and quality of life. Graphene oxide (GO) has excellent physical and chemical properties and plays an important role in the treatment of gliomas mainly through four applications, viz. direct killing, drug delivery, immunotherapy, and phototherapy. This article reviews research on GO nanocarriers in the treatment of gliomas in recent years and also highlights new ideas for the treatment of these tumors.

Modification of carbon-based nanomaterials by polyglycerol: recent advances and applications

Hyperbranched polymers, a subclass of dendritic polymers, mimic nature's components such as trees and nerves. Hyperbranched polyglycerol (HPG) is a hyperbranched polyether with outstanding physicochemical properties, including high water-solubility and functionality, biocompatibility, and an antifouling feature. HPG has attracted great interest in the modification of different objects, in particular carbon-based nanomaterials. In this review, recent advances in the synthesis and application of HPG to modify carbon-based nanomaterials, including graphene, carbon nanotubes, fullerene, nanodiamonds, carbon dots, and carbon fibers, are reviewed.

Modification of carbon nanomaterials by hyperbranched polyglycerol improves their properties.

Electrically Triggered Drug Delivery from Novel Electrospun Poly(Lactic Acid)/Graphene Oxide/Quercetin Fibrous Scaffolds for Wound Dressing Applications

The novel controlled and localized delivery of drug molecules to target tissues using an external electric stimulus makes electro-responsive drug delivery systems both feasible and desirable, as well as entailing a reduction in the side effects. Novel micro-scaffold matrices were designed based on poly(lactic acid) (PLA) and graphene oxide (GO) via electrospinning. Quercetin (Q), a natural flavonoid, was loaded into the fiber matrices in order to investigate the potential as a model drug for wound dressing applications. The physico-chemical properties, electrical triggering capacity, antimicrobial assay and biocompatibility were also investigated. The newly fabricated PLA/GO/Q scaffolds showed uniform and smooth surface morphologies, without any beads, and with diameters ranging from 1107 nm (10%PLA/0.1GO/Q) to 1243 nm (10%PLA). The in vitro release tests of Q from the scaffolds showed that Q can be released much faster (up to 8640 times) when an appropriate electric field is applied compared to traditional drug-release approaches. For instance, 10 s of electric stimulation is enough to ensure the full delivery of the loaded Q from the 10%PLA/1%GO/Q microfiber scaffold at both 10 Hz and at 50 Hz. The antimicrobial tests showed the inhibition of bacterial film growth. Certainly, these materials could be loaded with more potent agents for anti-cancer, anti-infection, and anti-osteoporotic therapies. The L929 fibroblast cells cultured on these scaffolds were distributed homogeneously on the scaffolds, and the highest viability value of 82.3% was obtained for the 10%PLA/0.5%GO/Q microfiber scaffold. Moreover, the addition of Q in the PLA/GO matrix stimulated the production of IL-6 at 24 h, which could be linked to an acute inflammatory response in the exposed fibroblast cells, as a potential effect of wound healing. As a general conclusion, these results demonstrate the possibility of developing graphene oxide-based supports for the electrically triggered delivery of biological active agents, with the delivery rate being externally controlled in order to ensure personalized release.

Adsorption and release on three-dimensional graphene oxide network structures

In this study, three-dimensional network architectures are constructed using nano-sized graphene oxide (nGO) as the building block. The cross-linking reaction of nGO is conducted in sub-micrometre water droplets in an emulsion system to control the size of the networks by restricting the reaction space. Two types of three-dimensional GO networks with different cross-linking lengths were constructed, and their methyl orange adsorption and release behaviours were investigated under external stimuli, such as thermal treatment, ultrasonic wave treatment and near-infrared light irradiation.

Superbranched polyglycerol nanostructures as drug delivery and theranostics tools for cancer treatment

Hyperbranched polymers (HBPs), such as hyperbranched polyglycerols (HPGs) with a dendritic configuration, have been recognized for their excellent biocompatibility and multifunctionalization. HPGs have been studied for use in the delivery diagnostic, imaging and therapeutic molecules in the area of nanobiomedicine. They show superior characteristics to linear polymers and dendrimers, such as compact structure, a simple manufacturing process with easy functionalization ability, low viscosity, and high stability. Owing to these advantages, HPGs are now considered promising carriers for drug delivery, diagnostics, imaging, and theranostics applications for cancer treatment. In this review, we also discuss safety aspects of HPG-based nanoformulations in various animal models and the clinical translation status of such polymers for real-time applications.

Preparation, characterization and anti-cancer activity of graphene oxide-‑silver nanocomposite

This work reported the preparation, characterization, cytotoxicity of green synthesized Lespedeza cuneate mediated silver nanoparticles (Lc-AgNPs) and graphene oxide‑silver nanocomposite (GO-AgNComp) using Lc-AgNPs. The UV absorption spectrum at 419 nm indicated the successful formation of GO-AgNComp. The TEM analysis displayed the thin sheet of graphene decorated Lc-AgNPs in GO-AgNComp. Zeta potential was -13.2 mV for Lc-AgNPs and -30.5 mV for GO-AgNComp. The photothermal conversion efficiency was calculated as 31.09% for GO-AgNComp. The negatively charged zeta potential of GO-AgNComp enhanced its cellular penetration through enhanced permeability and retention (EPR) effect. The near-infrared laser (NIR) induced the anticancer activity of Lc-AgNPs and GO-AgNComp in human lung cancer cells (A549) and brain tumour (LN229). The results indicated that about 50% of A549 cells and LN229 cells were ablated by treatment of 24.73 ± 2.98 μg/mL and 27.34 ± 1.62 μg/mL of Lc-AgNPs, as well by 15.46 ± 2.31 μg/mL and 20.95 ± 1.35 μg/mL of GO-AgNComp respectively. Moreover, GO-AgNComp was not cytotoxic to normal mouse fibroblast cells (NIH3T3), but it caused the cancer cell death in A549 and LN229 through ROS generation, nuclear damage, and mitochondrial membrane potential (∆ψm) loss. This work reported the anticancer potential of GO-AgNComp, which deserves further study on the molecular elucidation of GO-AgNComp mediated human lung and tumour therapy.

Polymer-Graphene Nanoassemblies and their Applications in Cancer Theranostics

BACKGROUND AND OBJECTIVE

Graphene-based nanomaterials have received increasing attention due to their unique physical-chemical properties including two-dimensional planar structure, large surface area, chemical and mechanical stability, superconductivity and good biocompatibility. On the other hand, graphene-based nanomaterials have been explored as theranostics agents, the combination of therapeutics and diagnostics. In recent years, grafting hydrophilic polymer moieties have been introduced as an efficient approach to improve the properties of graphene-based nanomaterials and obtain new nanoassemblies for cancer therapy.

METHODS AND RESULTS

This review would illustrate biodistribution, cellular uptake and toxicity of polymergraphene nanoassemblies and summarize part of successes achieved in cancer treatment using such nanoassemblies.

CONCLUSION

The observations showed successful targeting functionality of the polymer-GO conjugations and demonstrated a reduction of the side effects of anti-cancer drugs for normal tissues.

Pyromellitic dianhydride crosslinked cyclodextrin nanosponges for curcumin controlled release; formulation, physicochemical characterization and cytotoxicity investigations

Aim: In this study, a nanosponge structure was synthesised with capability of encapsulating curcumin as a model polyphenolic compound and one of the herbal remedies that have widely been considered due to its ability to treat cancer.Methods: FTIR, DSC and XRD techniques were performed to confirm the formation of the inclusion complex of the nanosponge-drug.Results: DSC and XRD patterns showed an increasing stability and a decreasing crystallinity of curcumin after formation of inclusion complex. Encapsulation efficiency was 98% (w/w) and a significant increase was observed in loading capacity (184% w/w). The results of cytotoxicity assessments demonstrated no cell toxicity on the healthy cell line, while being toxic against cancer cells. Haemolysis test was performed to evaluate the blood-compatibility characteristic of nanosponge and complex and the results showed 0.54% haemolysis in the lowest complex concentration (50μgml^-1) and 5.09% at the highest concentration (200μgml^-1).Conclusions: Thus, the introduced system could be widely considered in cancer treatment as a drug delivery system.

Cyclodextrin-Based Nanosystems as Drug Carriers for Cancer Therapy

BACKGROUND AND OBJECTIVE

Cyclodextrins have been of great interest as excellent candidates for fabricating versatile nano-drug delivery systems due to their commercial availability, easy functionalization, low immunogenicity, biocompatibility and safety. The possibility of reversible inclusion complex formation between cyclodextrins and various guest molecules in association with versatile exclusive properties of cyclodextrins offer a route towards the fabrication of highly sophisticated nanostructures with enormous potential for cancer treatment.

METHODS AND RESULTS

The current review discusses important recent advances in the fabrication and development of cyclodextrin-based nanostructures for cancer therapy. Firstly, the formation of inclusion complexes between cyclodextrin derivatives and anticancer compounds, as well as their application, are summarized. Secondly, the cyclodextrins -based nanosystems including cyclodextrin-containing polymers, cyclodextrin-based supramolecular necklaces, which consist of polyrotaxanes and polypseudorotaxanes and cyclodextrin based hydrogels accompanied by their applications in cancer treatment are highlighted. In the end, the future perspective of this field is discussed.

CONCLUSION

Numerous investigations in this area pave the way for the flourishing of the next generation of nano-therapeutics towards enhanced cancer therapy.

Fabricating β-cyclodextrin based pH-responsive nanotheranostics as a programmable polymeric nanocapsule for simultaneous diagnosis and therapy

Background

Fabrication of a smart drug delivery system that could dramatically increase the efficiency of chemotherapeutic drugs and reduce the side effects is still a challenge for pharmaceutical researchers. By the emergence of nanotechnology, a huge window was opened towards this goal, and a wide type of nanocarriers were introduced for delivering the chemotherapeutic to the cancer cells, among them are cyclodextrins with the ability to host different types of hydrophobic bioactive molecules through inclusion complexation process.

Aim

The aim of this study is to design and fabricate a pH-responsive theranostic nanocapsule based on cyclodextrin supramolecular nano-structure.

Materials and methods

This nanostructure contains iron oxide nanoparticles in the core surrounded with three polymeric layers including polymeric β-cyclodextrin, polyacrylic acid conjugated to sulfadiazine, and polyethylenimine functionalized with β-cyclodextrin. Sulfadiazine is a pH-responsive hydrophobic component capable of making inclusion complex with β-cyclodextrin available in the first and third layers. Doxorubicin, as an anti-cancer drug model, was chosen and the drug loading and release pattern were determined at normal and acidic pH. Moreover, the biocompatibility of the nanocapsule (with/without drug component) was examined using different techniques such as MTT assay, complement activation, coagulation assay, and hemolysis.

Results

The results revealed the successful preparation of a spherical nanocapsule with mean size 43±1.5 nm and negatively charge of −43 mV that show 160% loading efficacy. Moreover, the nanocapsule has an on/off switching release pattern in response to pH that leads to drug released in low acidic pH. The results of the biocompatibility tests indicated that this nano drug delivery system had no effect on blood and immune components while it could affect cancer cells even at very low concentrations (0.3 μg mL⁻¹).

Conclusion

The obtained results suggest that this is a “switchable” theranostic nanocapsule with potential application as an ideal delivery system for simultaneous cancer diagnosis and therapy.

An Improved Method for Fabrication of Ag-GO Nanocomposite with Controlled Anti-Cancer and Anti-bacterial Behavior; A Comparative Study

In this study, two green procedures for Silver-Graphene Oxide (Ag-GO) nanocomposite synthesis were investigated. As a common method, AgNO₃ was first loaded on the GO surface and then was reduced and stabilized by walnut green husk extract, producing Ag-GO-І. As an innovative approach, GO was first exposed to the extract and then the AgNO₃ was added as the second step, producing Ag-GO-П. Physicochemical properties, antibacterial and cytotoxicity activity of both nanocomposites were subsequently studied comparing with free silver nanoparticles (AgNPs) and pure GO. Based on the results, exposure of GO to the extract, as a reducing agent, at the first/last step of the synthesis process resulted in the fundamental differences in the final products. So that, high amounts of agglomerated silver nanoparticles were formed between the GO sheets, when using the common method, whereas in Ag-GO-П, small AgNPs were formed on the GO sheets without aggregation, entirely covering the sheets. Antibacterial and cytotoxic behavior of these nanomaterials could be compared as AgNPs > Ag-GO-П > Ag-GO-І. It is assumed that these differences are due to control of unwanted nucleation in the synthesis process that Ag nanoparticles are smaller with less agglomeration when the GO surfaces are pre-treated with reducing agent.

Combining antioxidant hydrogels with self-assembled microparticles for multifunctional wound dressings

A multi-functional composite to be employed as a dressing material was prepared by combining hydrogel and microparticle systems.

Selective cytotoxicity of green synthesized silver nanoparticles against the MCF-7 tumor cell line and their enhanced antioxidant and antimicrobial properties

Introduction

Silver nanoparticles (AgNPs) are of great interest due to their unique and controllable characteristics. Different synthesis methods have been proposed to produce these nanoparticles, which often require elevated temperatures/pressures or toxic solvents. Thus, green synthesis could be a replacement option as a simple, economically viable and environmentally friendly alternative approach for the synthesis of silver nanoparticles.

Methods

Here, the potential of the walnut green husk was investigated in the production of silver nanoparticles. An aqueous solution extracted from walnut green husk was used as a reducing agent as well as a stabilizing agent. Then, the synthesized nanoparticles were characterized with respect of their anticancer, antioxidant, and antimicrobial properties.

Results

Results showed that the synthesized nanoparticles possessed an average size of 31.4 nm with a Zeta potential of -33.8 mV, indicating high stability. A significant improvement in the cytotoxicity and antioxidant characteristics of the green synthesized Ag nanoparticles against a cancerous cell line was observed in comparison with the walnut green husk extract and a commercial silver nanoparticle (CSN). This could be due to a synergistic effect of the synthesized silver nanoparticles and their biological coating. AgNPs and the extract exhibited 70% and 40% cytotoxicity against MCF-7 cancerous cells, respectively, while CSN caused 56% cell death (at the concentration of 60 µg/mL). It was observed that AgNPs were much less cytotoxic when tested against a noncancerous cell line (L-929) in comparison with the control material (CSN). The free radical scavenging analysis demonstrated profound anti-oxidant activity for the synthesized nanoparticles in comparison with the extract and CSN. It was also detected that the synthesized AgNPs possess antibacterial activity against nosocomial and standard strains of both Gram-positive and Gram-negative bacteria (minimum inhibitory concentration =5-30 µg/mL).

Conclusion

These findings imply that the synthesized nanoparticles using green nanotechnology could be an ideal strategy to combat cancer and infectious diseases.