Topical silver and gold nanoparticles complexed with Cornus mas suppress inflammation in human psoriasis plaques by inhibiting NF-κB activity.

New biomaterials based on nanoparticles (NPs) carrying polyphenols-rich extracts (Cornus mas) recently showed promising anti-inflammatory activity in psoriasis. We aimed to understand how topically delivered silver and gold nanoparticles complexed with Cornus mas (Ag-NPs-CM, Au-NPs-CM) modulate inflammation in psoriasis at cellular and molecular level. The impact on psoriatic inflammation was assessed in vitro on pro-inflammatory macrophages, by clinical score, high-frequency ultrasonography and immunohistology of psoriasis plaques treated with Ag-NPs-CM, Au-NPs-CM or control. Incubation of pro-inflammatory macrophages with nanoparticles significantly decreased the release of NO, IL-12 and TNF-α. Immunofluorescence confirmed that nanoparticles significantly reduced CD68-positive macrophages and their IL-12 and TNF-α production in human psoriasis plaques. NPs-CM appear to repress NF-κB activation in macrophages, inhibiting the production of pro-inflammatory factors with causal role in psoriasis. Ag and Au NPs-CM represent a novel nanoparticle-based "green" technology which may provide an efficient tool for modern psoriasis therapy, circumventing immunosuppression-related side effects of biologicals.

In vitro and in vivo anti-inflammatory properties of green synthesized silver nanoparticles using Viburnum opulus L. fruits extract.

A green, rapid and cost effective method for the bio-synthesis of silver nanoparticles (AgNPs), using polyphenols present in European cranberry bush fruit extracts was developed. The obtained AgNPs were characterized by ultra-violet visible spectroscopy (UV-VIS), Fourier transform - infrared spectroscopy (FT-IR), transmission electron microscopy (TEM) and X-ray diffraction patterns (XRD). The average size of the spherical AgNPs was found to be 25nm. The anti-inflammatory effect of the biomaterials was investigated, both in vitro (on HaCaT cell line, exposed to UVB radiation) and in vivo (on acute inflammation model in Wistar rats). Our results support the conclusion that the photosynthesized silver nanoparticles present a potent anti-inflammatory activity and could be successfully used as therapeutic tools for treatment of inflammation.

Green synthesis, characterization and anti-inflammatory activity of silver nanoparticles using European black elderberry fruits extract.

This research aimed at reporting the synthesis, characterization and evaluation of the anti-inflammatory effects of some new biomaterials based on silver nanoparticles and polyphenols rich natural extracts. A fast and eco-friendly extracellular biosynthesis of silver nanoparticles (AgNPs), using European black elderberry (Sambucus nigra - SN, Adoxaceae family) fruit extracts was developed. The phytosynthesized nanoparticles exhibited an absorbance peak at 426nm, characteristic for AgNPs and their sizes were ranged from 20 to 80nm. The anti-inflammatory properties of AgNPs were assessed in vitro on HaCaT cells exposed to UVB radiation, in vivo on acute inflammation model and in humans on psoriasis lesions. In vitro, our results demonstrated the anti-inflammatory effects of functionalized AgNPs by the decrease of cytokines production induced by UVB irradiation. In vivo, the pre-administration of AgNPs reduced the edema and cytokines levels in the paw tissues, early after the induction of inflammation. The present study also demonstrated the possible use of synthesized AgNPs for the treatment of psoriasis lesions.

L-Leucine for gold nanoparticles synthesis and their cytotoxic effects evaluation.

This work reports the preparation of water-soluble leucine capped gold nanoparticles by two single-step synthesis methods. The first procedure involves a citrate reduction approach where the citrate is used as reducing agent and leucine as capping/stabilizing agent. Different sizes of gold nanoparticles, citrate reduced and stabilized by leucine, Leu-AuNPs-C, with the mean diameters in the range of 21-56 nm, were obtained by varying the macroscopic parameters such as: concentration of the gold precursor solution, Au (III):citrate molar ratio and leucine pH. In the second procedure, leucine acts both as reducing and stabilizing agent, allowing us to obtain spherical gold nanoparticles, Leu-AuNPs, with a majority of 80 % (with the mean diameter of 63 nm). This proves that leucine is an appropriate reductant for the formation of water-soluble and stable gold nanoparticles colloids. The characterization of the leucine coated gold nanoparticles was carried out by TEM, UV-Vis and FT-IR analysis. The cytotoxic effect of Leu-AuNPs-C and Leu-AuNPs was also evaluated.

Reversing chemoresistance of malignant glioma stem cells using gold nanoparticles.

The low rate of survival for patients diagnosed with glioblastoma may be attributed to the existence of a subpopulation of cancer stem cells. These stem cells have certain properties that enable them to resist chemotherapeutic agents and ionizing radiation. Herein, we show that temozolomide-loaded gold nanostructures are efficient in reducing chemoresistance and destroy 82.7% of cancer stem cells compared with a 42% destruction rate using temozolomide alone. Measurements of in vitro cytotoxicity and apoptosis indicate that combination with gold facilitated the ability of temozolomide, an alkylating drug, to alter the resistance of these cancer stem cells, suggesting a new chemotherapy strategy for patients diagnosed with inoperable recurrent malignant glioma.

New nanomaterials for the improvement of psoriatic lesions.

The main purpose of the present paper is to emphasize the non-invasive effect of some new prepared nanomaterials on skin diseases (psoriasis) together with the procedures to obtain them. These new materials are based on gold nanoparticles and natural compounds extracted from native plants of the Adoxaceae family (European cranberrybush -Viburnum opulus L. and European black elderberry -Sambucus nigra L.) and possess a known anti-inflammatory activity mainly due to their high content of anthocyanins and other polyphenols. The nanomaterials were characterized by transmission electron microscopy (TEM), UV-Vis spectroscopy, Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX) and thermogravimetric analysis (TGA). Studies in vivo and in vitro were made in order to determine the toxicity of the products. Based on the obtained nanomaterials, specific dermatological creams were prepared. Their effect on psoriatic lesions, in comparison with the hydrocortisone creams, was studied.

Electrically conductive gold-coated collagen nanofibers for placental-derived mesenchymal stem cells enhanced differentiation and proliferation.

Gold-coated collagen nanofibers (GCNFs) were produced by a single-step reduction process and used for the growth and differentiation of human adult stem cells. The nanomaterials were characterized by a number of analytical techniques including electron microscopy and spectroscopy. They were found to be biocompatible and to improve the myocardial and neuronal differentiation process of the mesenchymal stem cells isolated from the placental chorionic component. The expression of specific differentiation markers (atrium, natriuretic peptide, actin F and actin monomer, glial fibrilary acidic protein, and neurofilaments) was investigated by immunocytochemistry.

Coupling between plasmonic resonances in nanoparticles and porphyrins molecules.

A driving force for the growing interest in nanoassemblies is the use of nanoparticles linked to organic molecules. The goal of our research is to investigate the coupling of gold and silver nanoparticles (GNP and AgNP) with porphyrins molecules. We prepared water-soluble GNP and AgNP by reducing the noble metal complex salt with sodium citrate. The exchange of the initial ligand (citrate ions) with porphyrins formed hybrid nanostructures and change the electronic properties of GNP and AgNP. We highlighted the importance of the pH value to obtain the coupling of nanoparticles and porphyrins. We have shown that the absorption spectra of AgNP have a strong overlap with that of porphyrins. The effect of dye molecules on the plasmon properties of nanoparticles was demonstrated by UV-Vis, fluorescence and electrochemical spectroscopy (OTTLE cell). These new hybrid materials will be helpful for the design of light harvesting cells and sensors.

Manganese(III) porphyrin-based potentiometric sensors for diclofenac assay in pharmaceutical preparations.

Two manganese(III) porphyrins: manganese(III) tetraphenylporphyrin chloride and manganese(III)-tetrakis(3-hydroxyphenyl)porphyrin chloride were tested as ionophores for the construction of new diclofenac-selective electrodes. The electroactive material was incorporated either in PVC or a sol-gel matrix. The effect of different plasticizers and additives (anionic and cationic) on the potentiometric response was studied. The best results were obtained for the PVC membrane plasticized with dioctylphtalate and having sodium tetraphenylborate as a lipophilic anionic additive incorporated. The sensor response was linear in the concentration range 3 × 10(-6) - 1 × 10(-2) M with a slope of -59.7 mV/dec diclofenac, a detection limit of 1.5 × 10(-6) M and very good selectivity coefficients. It was used for the determination of diclofenac in pharmaceutical preparations, by direct potentiometry. The results were compared with those obtained by the HPLC reference method and a good agreement was found between the two methods.

Investigation of carbon nanofibers as support for bioactive substances.

In this paper we have studied the adsorption properties of various bio-active systems onto the surface of carbon nanofibers (CNF) synthesized by chemical vapor deposition (CVD). Amino acids (alanine, aspartic acid, glutamic acid) and glucose oxidase (GOx) were adsorbed on CNF and the results were compared with those obtained when activated carbon (AC) was used as support. CNF and AC properties (hydrophilic or hydrophobic properties) were characterized by the pH value, the concentration of acidic/basic sites and by naphthalene adsorption. CNF with immobilized GOx was additionally investigated as a highly sensitive glucose biosensor. An amperometric method was used in an original manner to detect the changes in the specific activity of GOx, immobilized longer time on CNF. The method demonstrates that not the whole enzyme adsorbed onto CNF can catalyze the oxidation of glucose from the solution.

Free Base Porphyrins as Ionophores for Heavy Metal Sensors.

Two functionalized porphyrins: 5,10,15,20-tetrakis(3,4-dimethoxyphenyl) porphyrin (A) and 5,10,15,20-tetrakis(3-hydroxyphenyl)porphyrin (B) obtained and characterized by us were used as ionophores (I) for preparing PVC-based membrane sensors selective to Ag⁺, Pb2+ and Cu2+. The membranes were prepared using three different plasticizers: (bis(2-ethylhexyl)sebacate (DOS), dioctylphtalate (DOP), o-nitrophenyl octyl ether (NPOE) and potassium tetrakis(4-chlorophenyl)borate (KTClPB) as additive. The functional parameters (linear concentration range, slope and selectivity) of the sensors with membrane composition: (I:PVC:KTClPB:Plasticizer) in different ratios were investigated. The best results were obtained for the membranes in the ratio I:PVC:KTClPB:Plasticizer 10:165:5:330. The influence of pH on the sensors response was studied. The sensors were used for a period of four months and their utility has been tested on synthetic and real samples.