Preparation of a selective L-phenylalanine imprinted polymer implicated in patients with phenylketonuria.

BACKGROUND: Molecular imprinting is a method for synthesizing polymers with structure-selective adsorption properties with applications such as, selectivity binding, drug delivery systems and anti-bodies. The present study aims at optimizing the preparation of molecularly imprinted polymer (MIP) against l-phenylalanine, in order to increase phenylalanine-binding in Enzymatic Intestinal Simulated Fluid (ESIF). METHODS: The MIP for l-phenylalanine, as a water-soluble template, was successfully synthesized without derivatization. Synthesization was done by a UV polymerization method in which methacrylic acid (MAA), as a functional monomer, and ethylene glycol dimethacrylate (EGDMA), as a cross-linker, were used in the presence of five different porogenic solvents including; acetonitrile, tetrahydrofuran (THF), chloroform, toluene and dimethyl sulfoxide (DMSO). The selectivity of the MIP was examined using 19 different amino acids in human serum and was evaluated by HPLC. In addition, morphological studies were conducted using SEM. RESULTS: The results showed that the obtained MIP with acetonitrile had the highest capacity and selectivity compared with other solvents. The data indicated that Phe-binding to MIP was significantly more than the former binding to NIP in EISF (P≤0.05). Moreover, in comparison with NIP and control group, MIP showed a better selectivity and binding for Phe. This could be used for the reduction of Phe in human serum samples of Phenylketonuria. CONCLUSION: Our findings suggest that the MIP against Phe prepared with acetonitrile, showed a good selectivity and binding, which caused a reduction of blood Phe concentration in enzymatic simulated intestinal fluid and human serum sample of Phenylketonuria.

Effect of laminated hydroxyapatite/gelatin nanocomposite scaffold structure on osteogenesis using unrestricted somatic stem cells in rat.

Bone matrix consists of two major phases at the nanoscale: organic and hydroxyapatite. Nanotechnology as a diverse and interdisciplinary area of research has the capacity to revolutionise many areas of applications such as bone tissue engineering. Nanohydroxyapatite/gelatin composite has higher osteoblast attachment and proliferation than micro-sized ones, and shorter culturing period and lower cell seeding density compared to pure gelatin. A nanostructured scaffold was fabricated by three methods for bone repair using nanohydroxyapatite and gelatin as the main components. Its biocompatibility, alizarin red test on the 14th and 21st days, gene expression on the 21st day in in vitro using and histomorphometry after 4 and 8 weeks post-implantation in the rat were investigated. Cultured unrestricted somatic stem cells used for in vitro study showed an excellent level of cell attachment to the scaffold. Cells induced more osteoblast differentiation on the scaffold than in 2D cell culture. Osteoblast differentiation and bone regeneration results of in vitro and in vivo investigation on scaffold were extremely significant, better than control and treatment groups. These effects could be attributed to the shape and size of nanoHA particles and good architecture of the scaffold. The results confirm the feasibility of bone regeneration using synthesised scaffold as a temporary bone substitute.

Synthesis, characterization and hepatoprotective effect of silymarin phytosome nanoparticles on ethanol-induced hepatotoxicity in rats.

Introduction: Silymarin proved to be a beneficial herbal medicine against many hepatic disorders such as alcoholic liver disease (ALD). However, its application is restricted due to its low bioavailability and consequently decreased efficacy. We herein used a nano-based approach known as "phytosome", to improve silymarin bioavailability and increase its efficacy. Methods: Phytosome nanoparticles (NPs) were synthesized using thin film hydration method. NPs size, electrical charge, morphology, stability, molecular interaction, entrapment efficiency (EE %) and loading capacity (LC %) were determined. Moreover, in vitro toxicity of NPs was investigated on mesenchymal stem cells (MSCs) viability using MTT assay. In vivo experiments were performed using 24 adult rats that were divided into four groups including control, ethanol (EtOH) treatment, silymarin/EtOH treatment and silymarin phytosome/EtOH, with 6 mice in each group. Experimental groups were given 40% EtOH, silymarin (50 mg/kg) and silymarin phytosome (200 mg/kg) through the gastric gavage once a day for 3 weeks. Biochemical parameters, containing ALP, ALT, AST, GGT, GPx and MDA were measured before and after experiment to investigate the protective effect of silymarin and its phytosomal form. And histopathological examination was done to evaluate pathological changes. Results: Silymarin phytosome NPs with the mean size of 100 nm were produced and were well tolerated in cell culture. These NPs showed a considerable protective effect against ALD through inverting the biochemical parameters (ALP, ALT, AST, GGT, GPx) and histopathological alterations. Conclusion: Silymarin phytosomal NPs can be used as an efficient treatment for ALD.

Erratum to "Nanotechnology in Wound Healing; Semisolid Dosage Forms Containing Curcumin-Ampicillin Solid Lipid Nanoparticles, in Vitro, Ex Vivo and in Vivo Characteristics".

[This corrects the article DOI: 10.15171/apb.2018.046.].

Convergence Science to Transform Biomedicine: A Narrative Review.

Recently convergence science was proposed and promoted in a large report from US National Science Foundation and Department of Commerce (NSF/DOC). The report was entitled "converging technologies for improving human performance. "It was dealing with converging of four technologies as: Nanotechnology, Biotechnology, Information technology and Cognitive science (NBIC). The report has gained tremendous popularity throughout the academia and scientific world. On Dec 2015 in a monthly meeting of the department of basic science of Iran Academy of Medical Science, the report of NSF/DOC on NBIC has been discussed. A working group has been established for more discussion and application in Iran. Several seminars in this regard have been performed, and presently this technology has been started as pilot in some technical universities in Iran. After US National Research Council (NCR) in the year 2014 and Massachusetts Institute of Technology (MIT) on convergence in biomedicine, the concept opened a new gate to approach solving medical and health care problems; the convergence technology in biomedical sciences has become interested and gained great popularity among the working group of convergence science in academy of medical science. This technology can lead to advances in fighting chronic diseases such as cancer, dementia, psychiatric disorders, disease of aging and others. The following is summary of proposed discussions in several gathered groups of scientists in this field.

Development and physicochemical, toxicity and immunogenicity assessments of recombinant hepatitis B surface antigen (rHBsAg) entrapped in chitosan and mannosylated chitosan nanoparticles: as a novel vaccine delivery system and adjuvant.

In this study chitosan nanoparticles (CS NPs) and mannosylated chitosan nanoparticles (MCH NPs) loaded with recombinant hepatitis B surface antigen (rHBsAg) was synthesized as a vaccine delivery system and assessed toxically and immunologically. The physicochemical properties of the nanoparticles (NPs) were determined by methods including scanning electron microscope (SEM) and dynamic light scattering (DLS). The morphology of the NPs was semi spherical and the average diameter of the loaded CS and MCH NPs was found to be 189 and 239 nm, respectively. The release studies showed that after the initial burst, both of the loaded NPs provided a continuous and slow release of the antigens. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed concentration and time dependent toxicity profile for both formulations, but rHBsAg loaded CS nanoparticle showed higher toxicity due to smaller particle size and larger zeta potential. Abnormal toxicity test (ATT) results showed no signs of toxicity in mice and guinea-pigs treated with loaded MCHNPs. Stability test for six months showed acceptable changes in size, surface charge, and antigenicity for loaded MCH nanoparticles. Finally, in vivo immunogenicity study revealed greater adjuvant capability of MCH nanoparticles than others formulations. Our results showed MCH NPs can be used as a controlled and targeted vaccine delivery system.

Biophysical, docking, and cellular studies on the effects of cerium oxide nanoparticles on blood components: in vitro.

INTRODUCTION: The application of nanoparticles (NPs) in medicine and biology has received great interest due to their novel features. However, their adverse effects on the biological system are not well understood. MATERIALS AND METHODS: This study aims to evaluate the effect of cerium oxide nanoparticles (CNPs) on conformational changes of human hemoglobin (HHb) and lymphocytes by different spectroscopic (intrinsic and synchronous fluorescence spectroscopy and far and near circular dichroism [CD] spectroscopy), docking and cellular (MTT and flow cytometry) investigations. RESULTS AND DISCUSSION: Transmission electron microscopy (TEM) showed that CNP diameter is ~30 nm. The infrared spectrum demonstrated a strong band around 783 cm-1 corresponding to the CNP stretching bond. Fluorescence data revealed that the CNP is able to quench the intrinsic fluorescence of HHb through both dynamic and static quenching mechanisms. The binding constant (Kb ), number of binding sites (n), and thermodynamic parameters over three different temperatures indicated that hydrophobic interactions might play a considerable role in the interaction of CNPs with HHb. Synchronous fluorescence spectroscopy indicated that microenvironmental changes around Trp and Tyr residues remain almost unchanged. CD studies displayed that the regular secondary structure of HHb had no significant changes; however, the quaternary structure of protein is subjected to marginal structural changes. Docking studies showed the larger CNP cluster is more oriented toward experimental data, compared with smaller counterparts. Cellular assays revealed that CNP, at high concentrations (>50 µg/mL), initiated an antiproliferative response through apoptosis induction on lymphocytes. CONCLUSION: The findings may exhibit that, although CNPs did not significantly perturb the native conformation of HHb, they can stimulate some cellular adverse effects at high concentrations that may limit the medicinal and biological application of CNPs. In other words, CNP application in biological systems should be done at low concentrations.

Nanotechnology in Wound Healing; Semisolid Dosage Forms Containing Curcumin-Ampicillin Solid Lipid Nanoparticles, in-Vitro, Ex-Vivo and in-Vivo Characteristics.

Purpose: Wound healing is a natural biologic process, but the duration of it may take too long. Trying to shorten this process is one of the challenges for scientists. Many technologies were applied to achieve this goal as well as nanotechnology. In this study semi solid formulations containing curcumin and ampicillin solid lipid nanoparticles (SLNs) were prepared to evaluate as burn wound healing agent. Methods: Curcumin as an anti-inflammatory and anti-bacterial agent and ampicillin as an antibiotic were applied. In-vitro and in-vivo evaluations were carried out. Particle size, loading efficiency, release profile, morphology and anti-bacterial efficacy of desired nanoparticles were evaluated at first. Then the remaining of the antibacterial effect in semi solid preparations was studied. Animal studies for both toxicology using rabbits and skin burn model using rats were designed. Pathology studies after applying of formulations was done too. Results: Desired nanoparticles were spherical in shape and particle size in range of 112-121 nm, with low zeta potential. For increasing stability of particles they were freeze dried using cryoprotectant. Lyophilized particles show no significant size enlargement. Results showed that both ointment and gel preparations have reasonable anti-bacterial effects, both of them cause increasing in the rate of wound healing in comparison with placebos and control groups and none of the formulations showed acute toxicity. Conclusion: It seems that using nanotechnology could shorten wound healing process to reduce treatment costs and increase compliance of patients.

Organelles and chromatin fragmentation of human umbilical vein endothelial cell influence by the effects of zeta potential and size of silver nanoparticles in different manners.

Recently, it has been disclosed that silver nanoparticles (AgNPs) have the potential to inhibit infection and cancerous cells and eventually penetrate through injected site into the capillary due to their small size. This study focuses on the effect of size and zeta potential of bare and citrate-coated AgNPs on human umbilical vein endothelial cells (HUVECs) as main capillary cells. AgNPs with high and low concentrations and no citrate coating were synthesized by using simple wet chemical method and named as AgNP/HC, AgNP/LC, and AgNP, respectively. Citrate coated particles showed larger zeta potential of -22 mV and AgNp/HC showed the smallest size of 13.2 nm. UV-Visible spectroscopy and dynamic light scattering (DLS) were performed to evaluate particle size and hydrodynamic diameter of NPs in water and cell culture media. Results indicated that higher concentrations of citrate decreased hydrodynamic diameter and NP agglomeration. reactive oxygen species (ROS) production of all AgNPs was similar at 28 ppm although it was significantly higher than control group. Their effects on cell membrane and chromosomal structure were studied using LDH measurement and 4',6-diamidino-2-phenylindole (DAPI) staining, as well. Results demonstrated that AgNP/LC was less toxic to cells owing to higher value of IC50, minimum inhibitory concentration (MIC), and less release of LDH. Cancerous (Human Caucasian neuroblastoma) and immortal cells (Mouse embryonic fibroblast cell line) were about twice more sensitive than HUVECs to toxic effects of AgNPs. DAPI staining results showed that AgNP and AgNP/HC induced highest and lowest breaking of chromosome. Overall results suggest that viability of HUVECs will be higher than 90% when viability of cancerous cells is 50% in AgNPs chemotherapy.

Synergic Antibacterial Effect of Curcumin with Ampicillin; Free Drug Solutions in Comparison with SLN Dispersions.

Purpose: This study was designed to investigate benefit of using nanotechnology on increasing of synergic antibacterial effect of natural and chemical antibacterial agents. Methods: At first the MIC and MBC of Curcumin and Ampicillin as selected antibacterial agents was determined, after that Solid Lipid Nanoparticles (SLNs) of each active ingredients as well as Curcumin-Ampicillin loaded SLNs were prepared using high pressure homogenization technique. Characterization of prepared SLNs was done, then MIC, MBC and contact killing time were investigated for Curcumin-Ampicillin loaded SLNs in comparison with free Curcumin and Ampicillin solutions as well as Ampicillin and Curcumin SLNs. Results: Based on results nanoparticles with the size of 150 nm show much more decreased MIC and MBC when Ampicillin and Curcumin were loaded together on SLNs than solutions in which free Ampicillin and Curcumin were mixed. Conclusion: It seems that using nanotechnology could cause decrease the dosage of antibiotics and risk of having antibiotic resistance bacteria strains.

Synthesis of a phenylalanine imprinted polymer for attenuation of phenylalanine absorption via the gut in a murine hyperphenylalaninemia model.

Polymer technology plays an influential role in biomedical sciences. Molecular imprinting is a technique for preparation of polymers with structure-selective adsorptive properties. High selectivities of these materials have nowadays advanced to the point that they are being utilized for several biomedical applications such as drug delivery. Phenylketonuria is a genetic disease characterized by accumulation of phenylalanine (Phe) in blood with toxic consequences. The aim of the present study is to synthesize a phenylalanine imprinted polymer for attenuation of phenylalanine absorption in the gut in a murine hyperphenylalaninemia model. A molecularly imprinted polymer (MIP) against Phe and a non-imprinted polymer (NIP) were synthesized and their Phe binding properties were studied in Simulated Intestinal Fluid (SIF). Two classes of binding sites were then found in the MIP: high affinity (KD = 62.5 µM) and low affinity (KD = 1 mM). Histological toxicity and LD50 of the MIP, after oral administration to murine hyperphenylalaninemia, were examined prior to investigation of the effects of the imprinted polymer on blood Phe concentrations in animal models. Our findings suggest that the MIP against Phe can decrease the blood Phe concentration in an animal model of hyperphenylalaninemia.