Improving quercetin anticancer activity through a novel polyvinylpyrrolidone/polyvinyl alcohol/TiO2 nanocomposite

A hydrogel nanocomposite comprising polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), and titanium oxide (TiO2) was prepared and encapsulated in a double emulsion as a pH-triggered delivery vehicle for quercetin (QC), an antitumor drug. Dynamic light scattering (DLS) was used to estimate the size and confirm the stability of QC-loaded nanoparticles. The interactions between the nanocomposite components, its crystalline structure and the morphology of the nanoparticles were characterized through Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM), respectively. Drug loading and encapsulation efficiency significantly improved after incorporation of TiO2, which corroborates the beneficial effect of this component. In vitro release experiments indicated the pH-responsivity of the nanocarrier, with higher amount of QC released in an acidic medium than at neutral pH. Due to the presence of a double emulsion, the release pattern was sustained and gradual in both environments. Cellular experiments including MTT assay and flow cytometry were conducted using U87 cell line to compare the anticancer activity of free QC and QCloaded nanoparticles. MTT assay was also performed on a noncancerous cell line (L929) to assess potential side effects of the drug release system. The results obtained herein confirm the suitability of the developed nanocarrier as an efficient drug delivery vehicle for tumor therapy.Comunidad de Madri

Novel Carboxymethyl cellulose-based hydrogel with core-shell Fe3O4@SiO2 nanoparticles for quercetin delivery

A nanocomposite composed of carboxymethyl cellulose (CMC) and core–shell nanoparticles of Fe3O4@SiO2 was prepared as a pH-responsive nanocarrier for quercetin (QC) delivery. The nanoparticles were further entrapped in a water-in-oil-in-water emulsion system for a sustained release profile. The CMC/Fe3O4@SiO2/QC nanoparticles were characterized using dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), a field emission scanning electron microscope (FE-SEM), and a vibrating sample magnetometer (VSM) to obtain insights into their size, stability, functional groups/chemical bonds, crystalline structure, morphology, and magnetic properties, respectively. The entrapment and loading efficiency were slightly improved after the incorporation of Fe3O4@SiO2 NPs within the hydrogel network. The dialysis method was applied for drug release studies. It was found that the amount of QC released increased with the decrease in pH from 7.4 to 5.4, while the sustained-release pattern was preserved. The A549 cell line was chosen to assess the anticancer activity of the CMC/Fe3O4@SiO2/QC nanoemulsion and its components for lung cancer treatment via an MTT assay. The L929 cell line was used in the MTT assay to determine the possible side effects of the nanoemulsion. Moreover, a flow cytometry test was performed to measure the level of apoptosis and necrosis. Based on the obtained results, CMC/Fe3O4@SiO2 can be regarded as a novel promising system for cancer therap

A Glassy Carbon Electrode Modified with Reduced Graphene Oxide and Gold Nanoparticles for Electrochemical Aptasensing Of Lipopolysaccharides from Escherichia Coli Bacteria

An electrochemical aptasensor is described for the voltammetric determination of lipopolysaccharide (LPS) from Escherichia coli 055:B5. Aptamer chains were immobilized on the surface of a glassy carbon electrode (GCE) via reduced graphene oxide and gold nanoparticles (RGO/AuNPs). Fast Fourier transform infrared, X-ray diffraction and transmission electron microscopy were used to characterize the nanomaterials. Cyclic voltammetry, square wave voltammetry and electrochemical impedance spectroscopy were used to characterize the modified GCE. The results show that the modified electrode has a good selectivity for LPS over other biomolecules. The hexacyanoferrate redox system, typically operated at around 0.3 V (vs. Ag/AgCl) is used as an electrochemical probe. The detection limit is 30 fg·mL−1. To decrease the electrochemical potential for detection of LPS, Mg/ carbon quantum dots were used as redox active media. They decrease the detection potentialto 0 V and the detection of limit (LOD) to 1 fg·mL−1. The electrode was successfully used to analyze serum of patients and healthy persons

Electrochemical nanobiosensor based on reduced graphene oxide and gold nanoparticles for ultrasensitive detection of microRNA-128

Acute lymphoblastic leukemia (ALL) is one of the most prevalent cancers in children and microRNA-128 is amongst the most useful biomarkers not only for diagnosis of ALL, but also for discriminating ALL from acute myeloid leukemia (AML). In this study, a novel electrochemical nanobiosensor based on reduced graphene oxide (RGO) and gold nanoparticles (AuNPs) has been fabricated to detect miRNA-128. Cyclic Voltametery (CV), Square Wave Voltametery (SWV) and Electrochemical Impedance Spectroscopy (EIS) have been applied to characterize the nanobiosensor. Hexacyanoferrate as a label-free and methylene blue as a labeling material were used in the design of the nanobiosensors. It was found that the modified electrode has excellent selectivity and sensitivity to miR-128, with a limit of detection of 0.08761 fM in label-free and 0.00956 fM in labeling assay. Additionally, the examination of real serum samples of ALL and AML patients and control cases confirms that the designed nanobiosensor has the potential to detect and discriminate these two cancers and the control samples.Comunidad de Madri

Nanoscale metal-organic frameworks as an advanced tool for medical applications: Challenges and recent progress

Recently, metal-organic frameworks (MOFs) have received a lot of interest for application in many fields ranging from catalysis, energy storage, and gas sensing to chemosensory and biomedicine owed to their flexible composition, tunable porosity, and easy functionalization ability. In particular, nanoscale MOFs have been broadly investigated as carriers for the delivery of therapeutics to cancerous organs owed to their high encapsulating capacity and controlled cargo release, versatility, biodegradability, and good biocompatibility. Several methods such as solvothermal, mechanochemical, electrochemical, microwave, and ultrasound have been utilized to fabricate MOFs via custom-made synthesis. Many efforts have been made to functionalize MOFs through "post-synthetic modification," by adjusting the nature, size, and charge of the linkers or tuning its main components. Herein, a comprehensive literature review on recent papers dealing with drug-loaded MOFs for the detection and treatment of cancer as well as bacterial, fungal, and viral infections is presented. Different types of MOFs applied as carriers in drug delivery systems and biosensing platforms are described. Furthermore, perspectives and challenges for future research in the field, particularly for cancer therapy, are discussed. Thus, very limited literature is available on in vitro and in vivo toxicity of nanoscale MOFs. Besides, their biological stability and long-term safety are crucial factors that should be further investigated. Based on the reviewed papers, zeolite imidazolate framework (ZIF) and Materials of Institute Lavoisier (MIL) families have been the main focus for drug delivery and diagnosis applications, respectively, while many types of MOFs have exhibited antibacterial and antifungal properties regardless of their cargo.Comunidad de Madri

Chitosan/Gamma-Alumina/Fe3O4@5-FU nanostructures as promising nanocarriers: physiochemical characterization and toxicity activity

Today, cancer treatment is an important issue in the medical world due to the challenges and side effects of ongoing treatment procedures. Current methods can be replaced with targeted nano-drug delivery systems to overcome such side effects. In the present work, an intelligent nano-system consisting of Chitosan (Ch)/Gamma alumina (gamma Al)/Fe3O4 and 5-Fluorouracil (5-FU) was synthesized and designed for the first time in order to influence the Michigan Cancer Foundation-7 (MCF-7) cell line in the treatment of breast cancer. Physico-chemical characterization of the nanocarriers was carried out using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), vibrating sample magnetometry (VSM), dynamic light scattering (DLS), and scanning electron microscopy (SEM). SEM analysis revealed smooth and homogeneous spherical nanoparticles. The high stability of the nanoparticles and their narrow size distribution was confirmed by DLS. The results of the loading study demonstrated that these nano-systems cause controlled, stable, and pH-sensitive release in cancerous environments with an inactive targeting mechanism. Finally, the results of MTT and flow cytometry tests indicated that this nano-system increased the rate of apoptosis induction on cancerous masses and could be an effective alternative to current treatments

Curcumin Sustained Release with a Hybrid Chitosan-Silk Fibroin Nanofiber Containing Silver Nanoparticles as a Novel Highly Efficient Antibacterial Wound Dressing

Drug loading in electrospun nanofibers has gained a lot of attention as a novel method for direct drug release in an injury site to accelerate wound healing. The present study deals with the fabrication of silk fibroin (SF)-chitosan (CS)-silver (Ag)-curcumin (CUR) nanofibers using the electrospinning method, which facilitates the pH-responsive release of CUR, accelerates wound healing, and improves mechanical properties. Response surface methodology (RSM) was used to investigate the effect of the solution parameters on the nanofiber diameter and morphology. The nanofibers were characterized via Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), zeta potential, and Dynamic Light Scattering (DLS). CS concentration plays a crucial role in the physical and mechanical properties of the nanofibers. Drug loading and entrapment efficiencies improved from 13 to 44% and 43 to 82%, respectively, after the incorporation of Ag nanoparticles. The application of CS hydrogel enabled a pH-responsive release of CUR under acid conditions. The Minimum Inhibitory Concentration (MIC) assay on E. coli and S. aureus bacteria showed that nanofibers with lower CS concentration cause stronger inhibitory effects on bacterial growth. The nanofibers do not have any toxic effect on cell culture, as revealed by in vitro wound healing test on NIH 3T3 fibroblasts

Construction of Aptamer-Based Nanobiosensor for Breast Cancer Biomarkers Detection Utilizing g-C3N4/Magnetic Nano-Structure

An electrochemical aptasensor has been developed to determine breast cancer biomarkers (CA 15-3). Aptamer chains were immobilized on the surface of the electrode by g-C3N4/Fe3O4 nanoparticles, which increased the conductivity and active surface area of the electrode. X-ray diffraction analysis (XRD), Fourier-transformed infrared spectroscopy (FTIR), and transmission electron microscopy (TEM) measurements have been carried out to characterize the nanomaterials. Cyclic voltammetry, square wave voltammetry, and electrochemical impedance spectroscopy have been used to characterize the developed electrode. The results demonstrate that the modified electrode has better selectivity for CA 15-3 compared to other biological molecules. It has a good electrochemical response to CA 15-3 with a detection limit of 0.2 UmL(-1) and a linear response between 1 and 9 UmL(-1). It has been used as a label-free sensor in potassium ferrocyanide medium and as methylene blue-labeled in phosphate buffer medium. This electrode was successfully applied to analyze the serum of diseased and healthy individuals, which corroborates its high potential for biosensing applications, especially for the diagnosis of breast cancer

Two-dimensional graphitic carbon nitride (g-C3N4) nanosheets and their derivatives for diagnosis and detection applications

The early diagnosis of certain fatal diseases is vital for preventing severe consequences and contributes to a more effective treatment. Despite numerous conventional methods to realize this goal, employing nanobiosensors is a novel approach that provides a fast and precise detection. Recently, nanomaterials have been widely applied as biosensors with distinctive features. Graphite phase carbon nitride (g-C3N4) is a two-dimensional (2D) carbon-based nanostructure that has received attention in biosensing. Biocompatibility, biodegradability, semiconductivity, high photoluminescence yield, low-cost synthesis, easy production process, antimicrobial activity, and high stability are prominent properties that have rendered g-C3N4 a promising candidate to be used in electrochemical, optical, and other kinds of biosensors. This review presents the g-C3N4 unique features, synthesis methods, and g-C3N4-based nanomaterials. In addition, recent relevant studies on using g-C3N4 in biosensors in regard to improving treatment pathways are reviewed