Glycerol is a plasticizer widely used due to its good plasticization efficiency, great availability, biocompatibility and low exudation. It is a renewable raw material that, when introduced in biodegradable films, promotes significant changes in its properties and, thus, guarantees a wide spectrum of application. In this work, corn straw was used to produce cellulose triacetate films from mixtures with glycerol (10%, 20% and 30%). The films were characterized by X-Ray Diffraction, Scanning Electron Microscopy, Thermogravimetric Analysis, Water Vapor Transport Rate and Water Vapor Permeation. The cellulose triacetate films produced with 20% glycerol have high barrier properties, when compared to films with concentrations 0, 10 and 30%.

A fast and simple procedure for simultaneous determination of propyphenazone (PRO), paracetamol (PAR) and caffeine (CAF) was performed using batch injection analysis with multiple pulse amperometric detection (BIA-MPA). Three potentials pulses were selected for the analysis: +0.90 V/50 ms: only PAR was oxidized; +1.20 V/50 ms: oxidation of PAR and PRO without the interference of CAF; +1.60 V/50 ms: oxidation of the three compounds (PAR, PRO and CAF). The sample aliquot (150 µL) was directly injected onto the boron-doped diamond (BDD) electrode immersed in a BIA cell. The analytical characteristics of the proposed method include high analytical frequency (75 injections per hour), good stability (RSD < 3.9%; n = 10), and low detection limits (0.3, 0.2 and 0.1 mg L−1 for PRO, PAR and CAF, respectively). The proposed method yielded similar results to those obtained by liquid chromatography at a 95% confidence level.

<p>A fast, simple procedure for simultaneous determination of sulfamethoxazole (SMX) and trimethoprim (TMP) was performed using batch injection analysis with multiple pulse amperometric detection (BIA-MPA). The sample aliquot (150 µL) was directly injected onto the boron-doped diamond (BDD) electrode (wall-jet configuration) immersed in a BIA system. The analytical characteristics of the proposed method include high analytical frequency (up to 75 injections per hour), good stability (RSD < 2.9%; n = 10), low detection limits (0.227 and 0.173 mg L^-1 for SMX and TMP, respectively) and minimal waste generation. The proposed method yielded similar results to those obtained by liquid chromatography at a 95% confidence level.</p>

A fluid conducting composite material prepared from graphite powder, commercial epoxy resin Araldite®, and cyclohexanone has been developed. The composition was optimized considering the mechanical properties as conductivity and adhesiveness using response surface methodology. This work employed cyclic voltammetry and amperometry to investigate the characteristics of such composite electrodes without and with the insertion of Prussian blue in the electrode body (bulk modified electrode). The composite electrodes were also successfully used for the amperometric detection of hydrogen peroxide at 0.0V vs Ag/AgCl.