Water dispersible electrically conductive poly(3,4- ethylenedioxythiophene) nanospindles by liquid crystalline template assisted polymerization

In this work, we demonstrate an inimitable liquid crystalline template strategy for the preparation of water dispersible electrically conducting poly(3,4-ethylenedioxythiophene) nanospindles (PEDOTSs). PEDOTSs were formed during the polymerization of the spindle shaped liquid crystalline phase of “EDOT–PDPSA” which was formed by the specific interactions of 3,4-ethylenedioxythiophene (EDOT) with 3-pentadecyl phenol-4-sulphonic acid (PDPSA). Liquid crystalline phases were characterized by Polarized Light Microscopic (PLM) analyses, rheology and XRD. Morphology and solid state ordering of conducting nanospindles were characterized by SEM, TEM and XRD. PEDOTSs exhibited an electrical conductivity of ~2.79 S cm⁻¹ and a good thermal stability (~300 °C), which suggests their applicability in fabricating high temperature electronic devices. Furthermore, electrochemical studies of PEDOTS modified glassy carbon electrodes (GCEs) showed an oxidation peak of ascorbic acid at a lower potential of 0.046 V with a peak current about 10 times (91.68 µA) higher than that of the bare GCE with excellent electrode stability, proposing that it can be used as a steady electrode for the electro-catalytic oxidation of similar molecules

Carboxy-terminated oligo(ethylene glycol)-alkane phosphate: synthesis and self-assembly on titanium oxide surfaces

The surface immobilization of oligo- and poly(ethylene glycol) on solids is a widely used approach to prevent the nonspecific adsorption of proteins, bacteria, and cells. A novel tri(ethylene glycol) derivative, phosphoric acid-mono(22-carboxy-12,15,18,21-tetraoxadocosyl) ester, was synthesized with the aim to produce self-assembled monolayers (SAMs) on metal/metal oxide surfaces. This compound contains two reactive, terminal moieties: the phosphoric acid group as anchor to the surface, and the carboxylic group as linker for further attachment of molecules such as peptides and proteins to be present at the surface. The adsorption on titanium-dioxide-coated substrates was studied quantitatively and the resulting SAMs were characterized by angle-dependent X-ray photoelectron spectroscopy (XPS) and spectroscopic ellipsometry. XPS data showed that the monomolecular layer is attached with the phosphate group to the substrate, but not fully ordered. The dry adlayer thickness was determined to be 13.4 A, which is less than expected for a densely packed monolayer. Surface concentration calculated from ellipsometry data resulted in a grafting density of 2.03 molecules/nm2

Single and Double Polymer Layer Arrangements of Acid Groups Containing Cellulose and Basic Groups Containing Polyethyleneimine on Steel

This paper presents the first results of a project aimed at investigating the arrangement of polyelectrolyte layers. on unalloyed steel. We studied the structure of double and single polymer layers consisting of cellulose phosphate (HP-PP-C) and polyethyleneimine (PEI). Layers were characterized by variable angle ellipsometry, AFM and XPS. In particular, XPS indicated the incorporation of iron ions into cellulose phosphate layers, but, in contrast, these ions could not be observed in PEI layers. Results indicated that the homogeneity and qualitative corrosion performance of double layers (HP-PP-C/PEI) on unalloyed steel depend on the deposition of cellulose phosphate at the interface with steel

Source attribution of community-acquired cases of Legionnaires’ disease–results from the German LeTriWa study

Introduction Sources of infection of most cases of community-acquired Legionnaires’ disease (CALD) are unknown. Objective Identification of sources of infection of CALD. Setting Berlin; December 2016–May 2019. Participants Adult cases of CALD reported to district health authorities and consenting to the study; age and hospital matched controls. Main outcome measure Percentage of cases of CALD with attributed source of infection. Methods Analysis of secondary patient samples for monoclonal antibody (MAb) type (and sequence type); questionnaire-based interviews, analysis of standard household water samples for Legionella concentration followed by MAb (and sequence) typing of Legionella pneumophila serogroup 1 (Lp1) isolates; among cases taking of additional water samples to identify the infectious source as appropriate; recruitment of control persons for comparison of exposure history and Legionella in standard household water samples. For each case an appraisal matrix was filled in to attribute any of three source types (external (non-residence) source, residential non-drinking water (RnDW) source (not directly from drinking water outlet), residential drinking water (RDW) as source) using three evidence types (microbiological results, cluster evidence, analytical-comparative evidence (using added information from controls)). Results Inclusion of 111 study cases and 202 controls. Median age of cases was 67 years (range 25–93 years), 74 (67%) were male. Among 65 patients with urine typable for MAb type we found a MAb 3/1-positive strain in all of them. Compared to controls being a case was not associated with a higher Legionella concentration in standard household water samples, however, the presence of a MAb 3/1-positive strain was significantly associated (odds ratio (OR) = 4.9, 95% confidence interval (CI) 1.7 to 11). Thus, a source was attributed by microbiological evidence if it contained a MAb 3/1-positive strain. A source was attributed by cluster evidence if at least two cases were exposed to the same source. Statistically significant general source types were attributed by calculating the population attributable risk (analytical-comparative evidence). We identified an external source in 16 (14%) cases, and RDW as source in 28 (25%). Wearing inadequately disinfected dentures was the only RnDW source significantly associated with cases (OR = 3.2, 95% CI 1.3 to 7.8) and led to an additional 8% of cases with source attribution, for a total of 48% of cases attributed. Conclusion Using the appraisal matrix we attributed almost half of all cases of CALD to an infectious source, predominantly RDW. Risk for LD seems to be conferred primarily by the type of Legionella rather than the amount. Dentures as a new infectious source needs further, in particular, integrated microbiological, molecular and epidemiological confirmation.Peer Reviewe