Rabbit Anti-Human ATR (Phospho-Ser428) polyclonal antibody

A novel nonleaching antimicrobial poly(vinyl alcohol)/poly(hexamethylene guanidine) hydrochloride (PVA/PHMG) hydrogel was prepared with freezing-thawing method. The hydrogen bond interaction between PVA and PHMG confirmed by ATR-FTIR spectra, endowed PVA/PHMG hydrogels with the nonleaching characteristic. These antimicrobial hydrogels behaved above 99.9% of antimicrobial rates against both E. coli and S. aureus, even after washing or soaking in water for 7 days. The PVA-0.100wt%PHMG hydrogel had 120% higher tensile strength than pure PVA hydrogel due to the reinforement of hydrogen bonding between PVA and PHMG. Furthermore, GO (graphene oxide) and SiO2 were respectively added to the PVA-0.100wt% PHMG system to reinforce the mechanical properties. PVA/PHMG/GO hydrogel and PVA/PHMG/SiO2 hydrogel were also prepared via freezing-thawing method. These two composite hydrogels still showed nonleaching antimicrobial properties and the antimicrobial rates were above 99.99% even after washing or soaking in water for 7 days. Compared with PVA/PHMG hydrogel, the -OH peak of the PVA/PHMG/SiO2 hydrogels in the infrared difference spectra shifted to the lower wavenumbers by 38 cm(-1), while the -OH peak of the PVA/PHMG/GO hydrogels shifted by 23 cm(-1). Therefore, the hydrogen bonding effect of SiO2 with PVA/PHMG might be stronger than that of GO. The hydrogen bond interactions among reinforcing agents, PVA and PHMG significantly enhanced the tensile strength of the hydrogel. The tensile strengths of PVA/PHMG/GO and PVA/PHMG/SiO2 hydrogels were 1.6 times and 3.3 times of that of PVA/PHMG hydrogels, respectively. This study provides a simple approach to develop reinforced and nonleaching antimicrobial PVA hydrogels.

Macroporous silicon (MPS) films were yielded by electrochemical anodization of p-type crystalline silicon in HF:DMF. Following, a Schottky structure was obtained by depositing polyaniline (PANI), which was doped with different contents of erbium (Er) using cyclic voltammetry method. The structural analysis showed the formation of pores with diameters ranging between 0.25 and 1.20 mu m and length around 15 mu m and, after PANI deposition, the diameter became about 17% lower. The chemical characterization by Energy dispersive X-ray spectroscopy (EDS) and Rutherford Backscattering Spectroscopy (RBS) pointed out that the erbium is primarily incorporated at polyaniline surface, but it spreads through the polymer layer and achieves the MPS/PANI interface. According to the Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) analysis, the presence of Er gave rise to the formation of additional functional groups besides that corresponding to polyaniline and silicon oxide phases. The optical characterization within the UV- vis region revealed a modified optical bandgap of PANI as a function of the Er doping concentration. The results of the electrical measurements pointed out to a lowering of the space charge region width in the silicon as well as a change of the PANI workfunction as a function of the Er doping. On the other hand, the current flow through the MPS/PANI Schottky junction was lowered by the increase of the Er doping and by the tunneling mechanism through a thin silicon oxide (approximate to 1-2 nm) grown on MPS during PANI deposition in aqueous solution.