This paper discusses the construction of a novel electrochemical sensor for 17β-estradiol (E2) based on a molecularly imprinted polymer (MIP)-conducting polymer modified hybrid electrode. A bifunctional monomer, N-phenylethylene diamine methacrylamide (NPEDMA), was used for the construction of the electrochemical sensor. Conducting films were prepared on the surface of a gold electrode by electropolymerization of the aniline moiety of NPEDMA. A layer of MIP was photochemically grafted over the polyaniline, via N,N-diethyldithiocarbamic acid benzyl ester (iniferter) activation of the methacrylamide groups. Computational modeling was used to select the most suitable monomer for preparation of MIPs for E2. Experimental parameters such as deposition time, cyclic voltammetric (CV) scan cycles, and conditions for polymer accumulation were optimized. The detection limit of the resulting sensor, determined by CV, was 6.86 × 10–7 M. Furthermore, the hybrid electrode was successfully used to analyze E2 in water without complex sample pretreatment. These results reveal that the MIP hybrid sensor has potential to be an effective technique for the electrochemical determination of E2 in real-time in complicated matrices.

A novel compound N-(N 0 ,N 0 -diethyldithiocarbamoylethylamidoethyl)aniline (NDDEAEA) was synthesized and fully characterized. Conjugated poly(NDDEAEA), consisting of N-substituted polyaniline (PANI) backbones with dithiocarbamate ester pendant groups (which can act as iniferters), was synthesized by both chemical and electrochemical polymerization. UV-initiated living polymerization was utilized to graft styrene, methacrylic acid (MAA), lauryl methacrylate, and acrylamido-2-methylpropanesulfonic acid (AMPSA) onto the conjugated macroiniferter which had previously been deposited on various surfaces (glass, polypropylene, polystyrene, and gold electrodes). The resultant polymeric surfaces were characterized by static contact angle measurements, XPS, SEM, and AFM. This versatile new material can be used for creating materials with integrated functionalities (e.g., conductivity, molecular recognition, catalysis and controlled transport properties, etc.) for application in sensors and microfluidic devices and for the construction of patterned surfaces.

Building blocks for a bright future: A new method for the synthesis of organic nanoparticles (NPs) was developed combining a molecularly imprinted polymer shell and a fluorescent dendrimer biosensing core. Cubic organic nanoparticles are reported for the first time. The polymeric nanoparticles could be used as a direct replacement for antibodies in biosensor applications.

A series of N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (TOEEDH4) ligand precursors and their group 4 metal complexes have been prepared. The complexes have been characterized by single-crystal X-ray diffraction and (1)H NMR spectroscopy, highlighting the ability to systematically vary the number of TOEED ligands within the system. Initial catalytic data for the solvent-free, ring-opening polymerization of rac-lactide (rac-LA), a promising degradable polymer produced from renewable resources, is reported. At 135 °C, it has been demonstrated that the activity of the complexes is enhanced by increasing the number of labile isopropoxide groups. When the temperature was further increased to 165 °C, all complexes demonstrated a far higher activity irrespective of the identity of the metal or number of labile initiator groups. Polymerization kinetics were monitored in real time using FT-IR spectroscopy with a diamond composite insertion probe and Ti4(TOEED)(O(i)Pr)12 was demonstrated to convert over 95% of the rac-LA within 160 min.

The selective separation of toluene from n-heptane is investigated using unsubstituted a-cyclodextrin (aCD), b-cyclodextrin (bCD) and also with two substituted CDs as a carrier in oil/water/oil-type emulsion liquid membranes. The separation factor for toluene to n-heptane is evaluated from the extraction of an equimolar mixture of toluene and n-heptane. bCD shows the highest selectivity followed by aCD, hydroxypropyl-aCD and hydroxypropyl-bCD. The separation performances, represented by the permeation rate and separation factor, are analyzed systematically by varying the operating parameters: contact time, concentration of carriers, volume fraction of the membrane phase, and the relative amount of solvent. In this paper the effects of carriers and interfacial tension on dispersed phase drop size, internal droplets size, and size distribution are also systematically investigated.