Smart multifunctional nanoparticles in nanomedicine

Recent advances in nanotechnology caused a growing interest using nanomaterials in medicine to solve a number of issues associated with therapeutic agents. The fabricated nanomaterials with unique physical and chemical properties have been investigated for both diagnostic and therapeutic applications. Therapeutic agents have been combined with the nanoparticles to minimize systemic toxicity, increase their solubility, prolong the circulation half-life, reduce their immunogenicity and improve their distribution. Multifunctional nanoparticles have shown great promise in targeted imaging and therapy. In this review, we summarized the physical parameters of nanoparticles for construction of "smart" multifunctional nanoparticles and their various surface engineering strategies. Outlook and questions for the further researches were discussed. © 2016 by De Gruyter

Aptamer mediated niosomal drug delivery

Development of nanoscale carrier systems for targeted drug delivery is crucial for cancer treatment. The current methods of drug delivery exhibit some problems such as lack of therapy efficiency at the desired parts of the body, degradation of the drug before reaching the desired tissue and limitations in cellular penetration. In this work, a novel drug delivery platform was developed to overcome these problems and to enable specific and efficient uptake into the cells. The surface of the synthesized polyethylene glycolated niosomes (PEGNIO) was modified with cell penetrating peptide (CPP) and cell specific MUC1 (S2.2) aptamer, and doxorubicin (DOX) as a cancer model drug was encapsulated in this platform. Fluorescence microscopy and flow cytometry analysis were used to investigate the cellular uptake and intracellular distribution of the DOX loaded niosomal formulation. In vitro cytotoxicity studies were carried out using MUC1 positive HeLa and negative U87 cells. Moreover, dynamic light scattering (DLS), zeta potential measurements and fluorescence absorption spectroscopy were performed to determine the vesicle size, as well as charge and spectroscopic properties of the conjugates. From these results, this novel aptamer mediated niosomal drug delivery platform may have application potential in targeted drug delivery towards MUC1-overexpressing tumors.Konrad Adenauer Foundatio

Niosomes as Nanoparticular Drug Carriers: Fundamentals and Recent Applications

Drug delivery systems are defined as formulations aiming for transportation of a drug to the desired area of action within the body. The basic component of drug delivery systems is an appropriate carrier that protects the drug from rapid degradation or clearance and thereby enhances drug concentration in target tissues. Based on their biodegradable, biocompatible, and nonimmunogenic structure, niosomes are promising drug carriers that are formed by self-association of nonionic surfactants and cholesterol in an aqueous phase. In recent years, numerous research articles have been published in scientific journals reporting the potential of niosomes to serve as a carrier for the delivery of different types of drugs. The present review describes preparation methods, characterization techniques, and recent studies on niosomal drug delivery systems and also gives up to date information regarding recent applications of niosomes in drug delivery.Konrad Adenauer Foundatio

Development of multifunctional nanoparticles for drug delivery and bioimaging

The rapid development of nanotechnology has offered novel therapeutic and diagnostic strategies to overcome limitations of conventional therapy. Creation of the materials at nanometer scale and manipulation of their properties have enabled to employ them in a number of biological applications such as in controlled drug delivery and bioimaging. Within this thesis, the physical parameters for construction of multifunctional nanoparticles were summarized and the application potential of polymeric nanoparticles and liposomes as a drug carrier and imaging vehicle were evaluated. Initially, amphiphilic hyperbranched copolymer as a drug nanocarrier was designed with dual peptides which can specifically bind to integrin αvβ3 with RGD, while Cys-TAT facilitates penetration through the cell membrane. After drug (doxorubicin (DOX)) encapsulation with detailed characterization, the applicability of the polymeric micelles was tested in glioblastoma and breast cancer cell lines that are αvβ3 integrin positive and negative, respectively. Thus, the effects of targeting ligand on the surface of nanoparticle were analyzed in terms of cellular uptake as well as toxicity. Targeted drug-loaded micelles showed stronger inhibition on the integrin αvβ3 receptor overexpressed cells compared to the drug-loaded micelles without peptides on the surface. Finally, liposome-nanoparticle hybrids were designed for co-delivery of imaging and therapeutic agents. Both hydrophobic nanoparticle (quantum dot (QD)) and hydrophilic drug (topotecan (TPT)) were encapsulated into liposomes and their further characterization was performed in detail. Drug release profile was observed under neutral and acidic conditions. In vitro analysis of the formulations was performed on cervical cancer cells. As a result, even though no targeting ligand was used on liposome surface, liposomal formulations were uptaken to the cells more efficiently compared to the free drug. Thus, the bioavailability of the imaging agent and therapeutic efficiency of the drug were enhanced by using theranostic liposome-QD hybrids. Overall, novel multifunctional polymeric and liposomal tools for drug delivery and bioimaging were designed and developed with different targeting strategies. These approaches might offer new possibilities for development of novel platforms in nanomedicine

Theranostic Liposome–Nanoparticle Hybrids for Drug Delivery and Bioimaging

Advanced theranostic nanomedicine is a multifunctional approach which combines the diagnosis and effective therapy of diseased tissues. Here, we investigated the preparation, characterization and in vitro evaluation of theranostic liposomes. As is known, liposome–quantum dot (L–QD) hybrid vesicles are promising nanoconstructs for cell imaging and liposomal-topotecan (L-TPT) enhances the efficiency of TPT by providing protection against systemic clearance and allowing extended time for it to accumulate in tumors. In the present study, hydrophobic CdSe/ZnS QD and TPT were located in the bilayer membrane and inner core of liposomes, respectively. Dynamic light scattering (DLS), zeta potential (ζ) measurements and fluorescence/absorption spectroscopy were performed to determine the vesicle size, charge and spectroscopic properties of the liposomes. Moreover, drug release was studied under neutral and acidic pH conditions. Fluorescence microscopy and flow cytometry analysis were used to examine the cellular uptake and intracellular distribution of the TPT-loaded L–QD formulation. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was utilized to investigate the in vitro cytotoxicity of the formulations on HeLa cells. According to the results, the TPT-loaded L–QD hybrid has adequate physicochemical properties and is a promising multifunctional delivery vehicle which is capable of a simultaneous co-delivery of therapeutic and diagnostic agents

Amine-intercalated montmorillonite matrices for enzyme immobilization and biosensing applications

WOS: 000300317700056Clay based biosensors were developed using montmorillonite (Mont) modified with methyl (M) and dimethylamine (DM). X-ray diffraction, Fourier transform infrared spectroscopy, zeta potential and thermal gravimetric measurements were used to characterize the modified clays. After immobilization of glucose oxidase (GOx) via clay on the glassy carbon electrode, its application as a glucose biosensor was investigated in detail. The best response characteristics were obtained by DM-Mont and optimization of enzyme amount, reproducibility of biosensor fabrication, repeatability of measurements and operational stability were all evaluated. The optimized biosensor showed a very good linearity between 0.05 mM and 1.0 mM, a 7 s response time and a limit of detection to glucose of 0.038 mM. Also, kinetic parameters and stabilities were determined. Apparent K-m and I-max values were found as 0.73 mM and 2.955 mu A, respectively. As well as batch configuration, the DM-Mont/GOx biosensor was successfully applied in the flow injection analysis mode. Finally, the performance of the DM-Mont/GOx biosensor to analyze glucose in a wine sample was compared with HPLC

Phyto-Niosomes: In Vitro Assessment of the Novel Nanovesicles Containing Marigold Extract

WOS: 000356875100006Herbal compounds, so-called phytoconstituents, illustrate poor absorption by living cells. Phytosomes are advanced form of herbal compounds that show higher absorption rate and bioavailability, which results better than conventional plant extracts. Niosomes, which are made of nonionic surfactants, create better chemical and stability conditions besides lipid vesicles. This study covers the preparation, characterization and cell culture applications of phyto-niosomes of Marigold extract. Before the encapsulation process, extracts of selected plants were prepared and the extract that presents best bioactivity was chosen. The resulting phyto-niosomes were characterized and their biological activities including cytotoxicity, wound healing and antioxidant activity were investigated.State Planning Organization (DPT) of Turkey [0395.STZ.2013-2]; Ege University Scientific Research ProjectsEge University [2013/FEN/023, 2013/FEN/022]; Ege University, Aliye Uster FoundationEge UniversityState Planning Organization (DPT) of Turkey is acknowledged for the financial support through the project number of 0395.STZ.2013-2. In addition, this work was partially supported by Ege University Scientific Research Projects (2013/FEN/023 and 2013/FEN/022). Ege University, Aliye Uster Foundation, is also acknowledged for the financial support

Nanostructured Amphiphilic Star-Hyperbranched Block Copolymers for Drug Delivery

A robust drug delivery system based on nanosized amphiphilic star-hyperbranched block copolymer, namely, poly­(methyl methacrylate-<i>block</i>-poly­(hydroxylethyl methacrylate) (PMMA-<i>b</i>-PHEMA) is described. PMMA-<i>b</i>-PHEMA was prepared by sequential visible light induced self-condensing vinyl polymerization (SCVP) and conventional vinyl polymerization. All of the synthesis and characterization details of the conjugates are reported. To accomplish tumor cell targeting property, initially cell-targeting (arginylglycylaspactic acid; RGD) and penetrating peptides (Cys-TAT) were binding to each other via the well-known EDC/NHS chemistry. Then, the resulting peptide was further incorporated to the surface of the amphiphilic hyperbranched copolymer via a coupling reaction between the thiol (−SH) group of the peptide and the hydroxyl group of copolymer by using <i>N</i>-(<i>p</i>-maleinimidophenyl) isocyanate as a heterolinker. The drug release property and targeting effect of the anticancer drug (doxorobucin; DOX) loaded nanostructures to two different cell lines were evaluated in vitro. U87 and MCF-7 were chosen as integrin α_vβ₃ receptor positive and negative cells for the comparison of the targeting efficiency, respectively. The data showed that drug-loaded copolymers exhibited enhanced cell inhibition toward U87 cells in compared to MCF-7 cells because targeting increased the cytotoxicity of drug-loaded copolymers against integrin α_vβ₃ receptor expressing tumor cells