A facile preparation of novel multifunctional vectors by non-covalent bonds for co-delivery of doxorubicin and gene.

In this study, novel multifunctional ternary complexes of biotinylated transferrin-avidin-biotin-poly(ethylene glycol)-poly(L-glutamate acid)/poly(2-(2-aminoethylamino) ethyl methacrylate)/doxorubicin-poly(L-aspartic acid)/pDNA (TAB/PIC-D/pDNA complexes) were prepared based on polyion complex micelles (PIC) and the avidin-biotin system, which aimed to target co-delivery of anti-cancer doxorubicin and gene. Cytotoxicity studies revealed that PIC-D could have anti-tumor effect on HeLa cells and HepG2 cells; TAB coating could increase the biocompatibility of PIC-D/pDNA complexes and the targeting delivery efficiency of doxorubicin. TAB/PIC-D/pDNA complexes possessed higher transfection efficiency than the unmodified complexes in serum, and transferrin could enhance luciferase expression in HeLa cells and HepG2 cells.

Cholesterol-based anionic long-circulating cisplatin liposomes with reduced renal toxicity.

Cholesterol anchored derivatives of 5-Cholestene-3-beta-ol 3-hemisuccinate (CHO-HS) and 1-cholesteryl-4-ω-methoxy-polyethylene glycol succinate (CHO-PEG) have been synthesized via esterification and employed at various ratios with di-stearoylphosphatidylcholine (DSPC) in the preparation of anionic long-circulating nanoliposmes for cisplatin (CDDP) delivery. In the present study, CHO-HS and CHO-PEG were characterized by FTIR and (1)H NMR. The particle size and zeta potential of liposomes were determined by Dynamic lights scattering (DLS).

Design of a photoswitchable hollow microcapsular drug delivery system by using a supramolecular drug-loading approach.

In this study, photoswitchable microcapsules were fabricated based on host-guest interactions between α-cyclodextrin (α-CD) and azobenzene (Azo). Carboxymethyl dextran-graft-α-CD (CMD-g-α-CD) and poly(acrylic acid) N-aminododecane p-azobenzeneaminosuccinic acid (PAA-C(12)-Azo) were assembled layer by layer on CaCO(3) particles. α-CD-rhodamine B (α-CD-RhB), used as a model drug, was loaded on PAA-C(12)-Azo layers by host-guest interaction.

A plug and play polymeric template driven by supramolecular interactions.

A new "plug and play" polymeric template with the driving force of host-guest interaction between β-CD and naphthalene-modified functional groups was designed and studied. Multiple functional groups can be loaded into the template directly and conveniently. Importantly, the "plug and play" effect of the polymeric template is reversible and the functional groups could be removed from the polymeric template conveniently by adding AD-HCl.

Bilayer matrix composed of polycation/DNA complex and sodium alginate gel as a tumor cell catcher.

A bilayer matrix consisting of TABP-SS/DNA complexes and sodium alginate gel is formed via electrostatic interaction. In vitro cell adhesion, proliferation and transfection of the bilayer matrix are investigated in HepG2, HeLa and COS7 cells. Results show that this matrix can only promote tumor cell attachment and growth.

A strategy to improve serum-tolerant transfection activity of polycation vectors by surface hydroxylation.

The aim of this contribution is to develop a universal method to promote the serum-tolerant capability of polycation-based gene delivery system. A "hydroxylation camouflage" strategy was put forward by coating the polycation vectors with hydroxyl-enriched "skin". Branched polyethyleneimine (PEI) was herein used as the polycation model and modified via the catalyst-free aminolysis reaction with 5-ethyl-5-(hydroxymethyl)-1,3-dioxan-2-oxo (EHDO).

Synthesis of dendrigraft poly(ϵ-caprolactone)s using side hydroxyl groups for the grafting of branch chains.

Dendrigraft poly(ϵ-caprolactone)s with high molecular weight and narrow polydispersity are synthesized via a convenient generation-growth approach. Copolymerization of ϵ-caprolactone (CL) and 4-(2-benzoxyethoxy)-ϵ-caprolactone (BECL) with stannous octanoate as a catalyst affords a functionalized poly(ϵ-caprolactone) (PCL) with benzyl-protected hydroxyl side groups. After removal of benzyl groups by palladium-catalyzed hydrogenolysis, the graft copolymerization of CL and BECL onto the hydroxyl-bearing linear polyester (zero-generation) affords the first-generation graft polyester.

A smart micellar system with an amine-containing polycarbonate shell.

The present paper reports the design and preparation of an amphiphilic triblock co-polymer poly(ε-caprolactone) (PCL)-poly(6,14-dimethyl-1,3,9,11-tetraoxa-6,14-diaza-cyclohexadecane-2,10-dione) (PADMC)-PCL and the use of micelles composed of them as carriers for pH-sensitive drug release. The triblock co-polymers were synthesized via two-step ring-opening polymerization with catalysis by Novozym-435 lipase. By adjusting the feed ratio, three co-polymers with different PCL lengths and the same PADMC length were produced.

Thermo-responsive shell cross-linked PMMA-b-P(NIPAAm-co-NAS) micelles for drug delivery.

Thermo-responsive amphiphilic poly(methyl methacrylate)-b-poly(N-isopropylacrylamide-co-N-acryloxysuccinimide) (PMMA-b-P(NIPAAm-co-NAS)) block copolymer was synthesized by successive RAFT polymerizations. The uncross-linked micelles were facilely prepared by directly dissolving the block copolymer in an aqueous medium, and the shell cross-linked (SCL) micelles were further fabricated by the addition of ethylenediamine as a di-functional cross-linker into the micellar solution. Optical absorption measurements showed that the LCST of uncross-linked and cross-linked micelles was 31.

Screening of Cd tolerant genotypes and isolation of metallothionein genes in alfalfa (Medicago sativa L.).

In order to evaluate Cd tolerance in wide-ranging sources of alfalfa (Medicago sativa) and to identify Cd tolerant genotypes which may potentially be useful for restoring Cd-contaminated environments, thirty-six accessions of alfalfa were screened under hydroponic culture. Our results showed that the relative root growth rate varied from 0.48 to 1.

PEG-detachable and acid-labile cross-linked micelles based on orthoester linked graft copolymer for paclitaxel release.

Polyethylene glycol detachable graft copolymer, mPEG-g-p(NAS-co-BMA), was synthesized by grafting 2-(ω-methoxy)PEGyl-1,3-dioxan-5-ylamine onto poly(N-(acryloyloxy)succinimide-co-butyl methacrylate). Pseudo in situ cross-linking of the mPEG-g-p(NAS-co-BMA) was performed in dimethylformamide phosphate buffer (v/v = 1/1) by an acid-labile diamine cross-linker bearing two symmetrical cyclic orthoesters. The cross-linked (CL) micelles with different contents of mPEG segments represented different morphologies.

Efficient non-viral gene delivery mediated by nanostructured calcium carbonate in solution-based transfection and solid-phase transfection.

Among different non-viral gene delivery methods, the technique of co-precipitation of Ca(2+) with DNA in the presence of inorganic anions is an attractive option because of the biocompatibility and biodegradability. In this study, nano-sized CaCO(3)/DNA co-precipitates for gene delivery were prepared. The effect of Ca(2+)/CO(3)(2-) molar ratio on the gene delivery was investigated.

Decolorization of different dyes by a newly isolated white-rot fungi strain Ganoderma sp.En3 and cloning and functional analysis of its laccase gene.

A laccase-producing white-rot fungi strain Ganoderma sp.En3 was newly isolated from the forest of Tzu-chin Mountain in China. Ganoderma sp.

Facile construction of nanofibers as a functional template for surface boron coordination reaction.

A facile strategy to perform the boron coordination reaction on a template of nanofibers is developed. Peptides with phenylboronic acid tails (peptidyl boronic acids) are designed and prepared as building blocks that can self-assemble into nanofibers. After the addition of vicinal diol structural motifs to the self-assembling system, matrix-assisted laser desorption-ionization time-of-flight mass spectrometry indicates that the boron coordination reaction occurs on the template of nanofibers, which results in the increase of the width and roughness of the nanofibers as demonstrated by transmission electron microscopy and atomic force microscopy measurements.

[A design of refractometer based on blur circle].

Objective: Design a convenient and stable eye refractometer based on the theory of blur circle.

Methods: Analyze the retinal blur circle in both Emsly reduced eye model and Liou & Brennan 1997 eye model by ZEMAX. Design the coefficients including PD (pupil diameter) and NO' (length between node point and fovea) with the purpose of improving the accuracy.

Targeted delivery in breast cancer cells via iodine: nuclear localization sequence conjugate.

The nonviral vector with iodine-nuclear localization sequence (namely, NLS-I) targeting breast cancer cells was fabricated. Ternary complexes were formed via charge interactions among NLS-I peptides, PEI 1800, and DNA, and we investigated their cellular internalization, nuclear accumulation as well as transfection efficiency. All the experiments were assessed by employing MCF-7 cells that express sodium/iodide symporter and HeLa cells that lack the expression of the symporter.

In situ formation of chitosan-cyclodextrin nanospheres for drug delivery.

Chitosan-cyclodextrin nanospheres were prepared by in situ formation through Michael addition between N-maleated chitosan (NMC) and per-6-thio-β-cyclodextrin sodium salt in an aqueous medium. This facile preparation method did not involve any organic solvent and surfactant. Through adjusting the preparation conditions, the nanospheres with a relatively narrow size distribution could be obtained.

Interface self-assembly to construct vertical peptide nanorods on quartz template.

A rationally designed glycyl-glycine derivative containing a light cleaved pyrenylmethyl ester tail was covalently bound onto the surface of quartz template. The interface self-assembly of this dipeptide building block induced the formation of chemically bound vertically aligned nanorods (CBVANs) with light sensitivity on the template.

Surface self-assembly of N-fluorenyl-9-methoxycarbonyl diphenylalanine on silica wafer.

N-Fluorenyl-9-methoxycarbonyl diphenylalanine (Fmoc-FF-OH) was chemically immobilized to the surface of silica wafer as the "seed". When immersing this peptide attached silica wafer into the dipeptide aqueous solution, the occurrence of a pH triggered surface self-assembly resulted in the formation of peptide nanorods on the surface of silica wafer. This surface self-assembly exhibited a dependence on the concentration of the dipeptide aqueous solution.

Amphiphilic Block-Graft Copolymers with a Degradable Backbone and Polyethylene Glycol Pendant Chains Prepared via Ring-Opening Polymerization of a Macromonomer.

Well-defined amphiphilic block-graft copolymers PCL-b-[DTC-co-(MTC-mPEG)] with polyethylene glycol methyl ether pendant chains were designed and synthesized. First, monohydroxyl-terminated macroinitiators PCL-OH were prepared. Then, ring-opening copolymerization of 2,2-dimethyltrimethylene carbonate (DTC) and cyclic carbonate-terminated PEG (MTC-mPEG) macromonomer was carried out in the presence of the macroinitiator in bulk to give the target copolymers.

Nanofibers Self-assembled from Structural Complementary Borono-decapeptides.

A series of structural complementary decapeptides with phenyl boronic acid tails or borono-decapeptides (BPs) were designed and synthesized for supramolecular self-assembly. After dissolving these borono-decapeptides in deionized (DI) water, well-defined nanofibers were formed in BP1 (B(OH)(2) VEKELVKEKL-OH) and BP3 (B(OH)(2) AELELARARL-OH). It was found that the self-assembled borono-decapeptide BP1 and BP3 have a parallel β-sheet conformation in the formed nanofibers.

Supramolecular architectures self-assembled from asymmetrical hetero cyclopeptides.

In this study, two asymmetrical cyclopeptides (CP1 and CP2) were designed and synthesized. The self-assembly behaviors of the asymmetrical cyclopeptides at varying pHs were investigated in terms of transmission electron microscopy (TEM), circular dichroism (CD), and Fourier transform infrared (FT-IR) spectroscopy. It was found that the self-assembly of CP1 resulted in the formation of nanofibers with α-helix conformation, while CP2 self-assembled into well-ordered nanorods with anti-parallel β-sheet conformation.

Hyperbranched polycarbonate-based multimolecular micelle with enhanced stability and loading efficiency.

We herein develop a facile catalyst-free method to prepare hyperbranched hydroxyl-enriched aliphatic polycarbonate according to SCROP strategy. PEG-attached multiarm hyperbranched copolymer HEHDO-star-mPEG was further designed. It was found that HEHDO-star-mPEG can self-assemble into supramolecular multimolecular micelles in water.

Polycarbonate microspheres containing mitomycin C and magnetic powders as potential hepatic carcinoma therapeutics.

The polycarbonate copolymer poly(trimethylene carbonate-co-5,5-dimethyl trimethylene carbonate) (P(TMC-co-DTC)) was synthesized by the polymerization of trimethylene carbonate (TMC) and 5,5-dimethyl trimethylene carbonate (DTC) using tin (II) 2-ethylhexanoate [Sn(Oct)(2)] as a catalyst. In vitro degradation tests indicated this polycarbonate copolymer degraded slowly in phosphate buffer saline solution (PBS, 0.1 mol/L, at 37°C).