In this study, a novel hemocompatible coating on stainless steel substrates was prepared by electrochemically copolymerizing 3,4-ethylenedioxythiophene (EDOT) with graphene oxide (GO), polystyrene sulfonate (PSS), or heparin (HEP) on SUS316L stainless steel, producing an anti-fouling (anti-protein adsorption and anti-platelet adhesion) surface to avoid the restenosis of blood vessels. The negative charges of GO, PSS, and HEP repel negatively charged proteins and platelets to achieve anti-fouling and anti-clotting. The results show that the anti-fouling capability of the poly(3,4-ethylenedioxythiophene) (PEDOT)/PSS coating is similar to that of the PEDOT/HEP coating. The anti-fouling capability of PEDOT/GO is higher than those of PEDOT/HEP and PEDOT/PSS. The reason for this is that GO exhibits negatively charged functional groups (COO−). The highest anti-fouling capability was found with the PEDOT/GO/HEP coating, indicating that electrochemical copolymerization of PEDOT with GO and HEP enhances the anti-fouling capability. Furthermore, the biocompatibility of the PEDOT coatings was tested with 3T3 cells for 1–5 days. The results show that all PEDOT composite coatings exhibited biocompatibility. The blood clotting time (APTT) of PEDOT/GO/HEP was prolonged to 225 s, much longer than the 40 s of pristine SUS316L stainless steel (the control), thus greatly improving the anti-blood-clotting capability of cardiovascular stents.
We have successfully fabricated poly(3,4-ethylenedioxythiophene) (PEDOT) derivative nanohybrid coatings on flexible SUS316L stainless steel by electrochemical polymerization, which can offer anti-fouling and anti-bacterial capabilities. PEDOT derivative nanohybrids were prepared from polystyrene sulfonates (PSS) and graphene oxide (GO) incorporated into a conducting polymer of PEDOT. Additionally, the negative charge of the PEDOT/GO substrate was further modified by poly-diallyldimethylammonium chloride (PDDA) to form a positively charged surface. These PEDOT derivative nanohybrid coatings could provide a straightforward means of controlling the surface energy, roughness, and charges with the addition of various derivatives in the electrochemical polymerization and electrostatically absorbed process. The characteristics of the PEDOT derivative nanohybrid coatings were evaluated by Raman spectroscopy, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), water contact angle, and surface potential (zeta potential). The results show that PEDOT/PSS and PEDOT/GO nanohybrid coatings exhibit excellent anti-fouling capability. Only 0.1% of bacteria can be adhered on the surface due to the lower surface roughness and negative charge surface by PEDOT/PSS and PEDOT/GO modification. Furthermore, the anti-bacterial capability (7 mm of inhibition zone) was observed after adding PDDA on the PEDOT/GO substrates, suggesting that the positive charge of the PEDOT/GO/PDDA substrate can effectively kill bacteria (Staphylococcus aureus). Given their anti-fouling and anti-bacterial capabilities, PEDOT derivative nanohybrid coatings have the potential to be applied to biomedical devices such as cardiovascular stents and surgical apparatus.
Environmental-friendly nanocomposite hydrogels of carboxymethyl-hexanoyl chitosan (CHC), graphene oxide (GO) and cellulose nanocrystals (CNCs) were combined to produce a bio-hydrogel with great biocompatibility and antibacterial ability. The size of the GO nanosheets was about 200–500 nm, and the CNCs had a length of 100–200 nm and a width of 10–20 nm, as shown by transmission electron microscopy (TEM). X-ray photoelectron spectroscopy (XPS) was utilized for the analysis of the oxygen functional groups of GO. The homogeneous dispersion of the CHC/GO/CNC nanocomposite hydrogel showed significantly higher water absorption capacity and water retention capability. In addition, inhibition of a variety of microorganisms (gram-negative and gram-positive bacteria and fungi) by the introduction of the CHC/GO/CNC nanocomposite hydrogel demonstrated that there is a great opportunity to use it in the bio-medical field, such as for plastic masks and wound dressings.
Background: In situ simulation is the practice of using simulated scenarios to improve skill implementation, train critical thinking and problem-solving abilities, and enhance self-efficacy. This study aimed to enhance nursing knowledge, skills, and attitudes toward clinical work by applying in situ simulation training to improve the healthcare of critically ill patients. Methods: This study was conducted from a medical center in northern Taiwan and included 86 trainees who received intensive care training courses from 1 June 2017 to 31 May 2019. The self-report knowledge assessment, empathetic self-efficacy scale, skill assessment, and attitudes of instructors before and after training were collected. The statistical analysis used the Wilcoxon test for knowledge and attitudes, and chi-square tests were used for skills to evaluate the learning effect. Results: The results showed a statistically significant improvement in knowledge, skills, attitudes, and empathy in nursing care. Conclusions: In situ simulation learning can be an accepted method for nursing skills in the intensive care unit. Through this study, we understood that the in situ simulation method was beneficial to nurses’ care and care thinking processes. It is worth developing and evaluating integrated simulation education to enhance learning, change behavior, and promote holistic care in the nursing field.
Magnetic reduced graphene oxide (MRGO) sheets were prepared by embedding Fe3O4 nanoparticles on polyvinylpyrrolidone (PVP) and poly(diallyldimethylammonium chloride) (PDDA)-modified graphene oxide (GO) sheets for bacteria capture and destruction under a high-frequency magnetic field (HFMF). The characteristics of MRGO sheets were evaluated systematically by transmission electron microscopy (TEM), scanning electron microscopy (SEM), zeta potential measurement, X-ray diffraction (XRD), vibrating sample magnetometry (VSM), and X-ray photoelectron spectroscopy (XPS). TEM observation revealed that magnetic nanoparticles (8–10 nm) were dispersed on MRGO sheets. VSM measurements confirmed the superparamagnetic characteristics of the MRGO sheets. Under HFMF exposure, the temperature of MRGO sheets increased from 25 to 42 °C. Furthermore, we investigated the capability of MRGO sheets to capture and destroy bacteria (Staphylococcus aureus). The results show that MRGO sheets could capture bacteria and kill them through an HFMF, showing a great potential in magnetic separation and antibacterial application.