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Recently, the microwave‐assisted heating method has become a commonly used and environmentally friendly heating technology in the field of organic and polymeric synthetic chemistry. A series of poly(5,5‐dimethyl trimethylenecarbonate‐co‐2‐phenyl‐5,5‐bis[oxymethyl] trimethylenecarbonate) (P[DTC‐co‐PTC]) were synthesized by microwave‐assisted ring‐opening polymerization of 5,5‐dimethyl trimethylene carbonate (DTC) and 2‐phenyl‐5,5‐bis(oxymethyl) trimethylene carbonate (PTC) using tin(II) 2‐ethylhexanoate and aluminum isopropoxidase, the catalysts. These co‐polycarbonates were further reduced by a palladium‐carbon catalyst (Pd/C catalyst, 10%) to make partly deprotected polycarbonates (HPDPC). These two co‐polycarbonates were characterized by gel permeation chromatography, 1HNMR, Fourier transform infrared spectroscopy, UV, differential scanning calorimetry, and automatic contact‐angle measurements. The influences of the microwave irradiation time, microwave power, monomer feed molar ratio, different catalysts, and monomer/catalyst feed molar ratio on the molecular weights of co‐polycarbonates were also investigated. In vitro water absorption, degradation and drug release tests indicated that partly deprotected co‐polycarbonate HPDPC possessed greater hydrophilicity, faster degradation rate, and faster drug release rate than that of corresponding P(DTC‐co‐PTC). Therefore, microwave‐assisted polymerization is a clean and cheap heating method and can be used for ring‐opening copolymerization of carbonates, which enhances the hydrophilicity and biodegradation rate of aliphatic polycarbonates. [ABSTRACT FROM AUTHOR]

Targeted tumor imaging in vivo has been one of the main challenges in the early stage of cancer diagnosis and therapy. However, few contrast probes are available to specifically respond to tumor environments. The aim was to investigate porphyrin‐1,8‐naphthalimide derivative (APTSPP‐2NI) as a potential tumor‐targeting fluorescent probe in vitro and in vivo. A tumor‐targeting APTSPP‐2NI was synthesized by the incorporation of water‐soluble 5‐(4'‐aminophenyl)‐10,15,20‐tris(4'‐sulfonato‐phenyl) porphyrin (APTSPP) as a tumor‐targeting group into N‐butyl‐4‐ethyldiamino‐1,8‐naphthalene imide (NI) fluorescence molecule herein. The derivative was further characterized and its properties in vitro and in vivo including the cell cytotoxicity, cell uptake of tumor cells and fluorescent imaging were also evaluated. Experiment results indicated that APTSPP‐2NI possessed the low cell cytotoxicity and good tumor‐targeting property to the B16F10 melanoma cells. Moreover, APTSPP‐2NI can be taken up highly by B16F10 melanoma tumors and then achieve the good green and red fluorescent imaging in B16F10 melanoma tumors. Therefore APTSPP‐2NI can be considered as a potential tumor‐targeting dual‐mode enhanced probe in fluorescent imaging in vitro and in vivo. [ABSTRACT FROM AUTHOR]

In recent decades, diverse drug delivery systems (DDS) constructed by self-assembly of dendritic peptides have shown advantages and improvable potential for cancer treatment. Here, an arginine-enriched dendritic amphiphilic chimeric peptide CRRK(RRCG(Fmoc))2 containing multiple thiol groups is programmed to form drug-loaded nano-micelles by self-assembly. With a rational design, the branched hydrophobic groups (Fmoc) of the peptides provide a strong hydrophobic force to prevent the drug from premature release, and the reduction-sensitive disulfide linkages formed between contiguous peptides can control drug release under reducing stimulation. As expected, specific to multidrug resistance (MDR) tumor cells, the arginine-enriched peptide/drug (PD) nano-micelles show accurate nuclear localization ability to prevent the drug being pumped by P-glycoprotein (P-gp) in vitro, as well as exhibiting satisfactory efficacy for MDR tumor treatment in vivo. This design successfully realizes stimuli-responsive drug release aimed at MDR tumor cells via an ingenious sequence arrangement. [ABSTRACT FROM AUTHOR]

Isoindoline nitroxide-containing porphyrins were synthesized by the reaction of 5-phenyldipyrromethane and 5-(4′-nitrophenyl)-dipyrromethane with 5-formyl-1,1,3,3-tetramethylisoindolin-2-yloxyl using the Lindsey method. These spin-labeled porphyrins were further characterized by MS, UV, FTIR, 1H-NMR, cyclic voltammetry, electron paramagnetic resonance (EPR), and fluorescence spectroscopy. The electrochemical assay demonstrated that these isoindoline nitroxides-containing porphyrins had similar electrochemical and redox properties as 5-carboxy-1,1,3,3-tetramethylisoindolin-2-yloxyl. Electron paramagnetic resonance test exhibited these porphyrins possessed the hyperfine splittings and characteristic spectra of isoindoline nitroxides, with typical nitroxide g-values and nitrogen isotropic hyperfine coupling constants. Fluorescence spectroscopy revealed that these porphyrins indicated fluorescence suppression characteristic of nitroxide-fluorophore systems. Moreover, their reduced isoindoline nitroxide-containing porphyrins eliminated the fluorescence suppression and displayed strong fluorescence. Thus, these isoindoline nitroxide-containing porphyrins may be considered as the potential fluorescent and EPR probes. [ABSTRACT FROM AUTHOR]

ABSTRACT Polycarbonate microspheres TT-PC containing tetanus toxoid vaccine (TT) were prepared by the modified water-in-oil-in-water (W/O/W) solvent evaporation technique, using poly(trimethylene carbonate- co−5,5-dimethyl trimethylene carbonate) (P(TMC- co-DTC), or PC) as a polymeric carrier. TT release studies showed that the microspheres sustained a steady release rate of TT in the phosphate buffer saline solution (0.1 mol L−1, pH 7.4) in vitro for 60 days. In vivo cytotoxicity assays demonstrated that the polycarbonate microspheres had low toxicity and high safety in vivo in guinea pigs. Immunity and inoculation tests indicated that the TT-PC microspheres acted as an immunological adjuvant in vivo in guinea pigs. In guinea pigs attacked with an active tetanus toxoid, an injection of the TT-PC microspheres with a single-dose and booster vaccination induced high levels of antitoxin efficiencies in the blood serum, showing good immunoprotection. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014, 131, 40048. [ABSTRACT FROM AUTHOR]

The polycarbonate copolymers poly[trimethylene carbonate- co-2-phenyl-5,5-bis(hydroxymethyl) trimethylene carbonate] [P(TMC- co-PTC)] were synthesized by the ring-opening polymerization of trimethylene carbonate (TMC) and 2-phenyl-5,5-bis(hydroxymethyl) trimethylene carbonate (PTC) with tin(II) 2-ethylhexanoate and aluminum isopropoxide as the catalysts. These copolymers were further reduced by a palladium/carbonate (Pd/C; 10%) catalyst to produce partly deprotected copolymers. These two types of copolymers were characterized by 1H-NMR, Fourier transform infrared spectroscopy, UV spectroscopy, gel permeation chromatography, differential scanning calorimetry, and an automatic contact angle meter. The influences of the feed molar ratio of the monomers, the catalyst concentration, the reaction time, and the reaction temperature on the copolymerization process were also studied. The copolymerization of the TMC and PTC monomers was a nonideal copolymerization, and the copolymerization reactivity ratio of TMC was higher than that of PTC. In vitro degradation tests indicated that the partly deprotected copolymers possessed faster degradation rates and more hydrophilicity than the corresponding unreduced copolymers. Moreover, the degradation of these two type copolymers increased when the pH value of the buffer solutions decreased. In vitro drug-release experiments showed that these two types of copolymers had steady drug-release rates and good controlled release properties. Moreover, the partly deprotected copolymers had faster drug-release rates than the corresponding unreduced copolymers. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

The article discusses a study which examined the synthesis of a series of copolymers through the ring-opening bulk polymerization of ε-caprolactone (CL) and 2-phenyl-5,5-bis(hydroxymethyl) trimethylene carbonate (PTC) containing tin(II) 2-ethyhexanoate. It notes the use of a palladium/carbonate catalyst for the further reduction of copolymers. Results of the study showed that CL and PTC copolymerization was nonideal and that the reactivity ratio of CL was higher than that of PTC.

The article presents information on a study which described the preparation and copolymerization of six-membered cyclic carbonate monomers like 2-phenyl-5,5-bis(hydroxymethyl) trimethylene carbonate (PTC) and 5,5-dimethyl trimethylene carbonate (DTC). A review of the related literature is given. Methods utilized include Fourier transform infrared and ultraviolet, among others, while tin(II) 2-ethylhexanoate and aluminum isopropoxide were used as initiators. It discusses the research findings.

The article discusses a study which involved the development of anticancer magnetic polymer microspheres with tumor necrosis factor-α (TNF-α) genes. The water-in-oil-in-water solvent evaporation technique was used to produce the polymer microspheres with results showing a sustained release rate of the TNF-α genes for up to 60 hours. A new method of drug release for liver carcinoma treatment shown by high antitumor activity and inhibitory rate of the microspheres is proposed.

A novel supramolecular framework, catena-poly[[[aqua(2-phenylquinoline-4-carboxylato-κ O)silver(I)]-μ-4,4′-bipyridine-κ2 N: N′] dihydrate], {[Ag(C16H10NO2)(C10H8N2)(H2O)]·2H2O} n, has been synthesized and structurally characterized. The AgI centres are four-coordinated and bridged by 4,4′-bipyridine (4,4′-bipy) ligands to form a one-dimensional Ag-bipy chain. The Ag-bipy chains are further linked together by intermolecular O-H...O and O-H...N hydrogen-bonding interactions between adjacent chains, resulting in a three-dimensional framework. [ABSTRACT FROM AUTHOR]