Development of Polymer-Encapsulated, Amine-Functionalized Zinc Ferrite Nanoparticles as MRI Contrast Agents

The need for stable and well-defined magnetic nanoparticles is constantly increasing in biomedical applications; however, their preparation remains challenging. We used two different solvothermal methods (12 h reflux and a 4 min microwave, MW) to synthesize amine-functionalized zinc ferrite (ZnFe2O4-NH2) superparamagnetic nanoparticles. The morphological features of the two ferrite samples were the same, but the average particle size was slightly larger in the case of MW activation: 47 ± 14 nm (Refl.) vs. 63 ± 20 nm (MW). Phase identification measurements confirmed the exclusive presence of zinc ferrite with virtually the same magnetic properties. The Refl. samples had a zeta potential of -23.8 ± 4.4 mV, in contrast to the +7.6 ± 6.8 mV measured for the MW sample. To overcome stability problems in the colloidal phase, the ferrite nanoparticles were embedded in polyvinylpyrrolidone and could be easily redispersed in water. Two PVP-coated zinc ferrite samples were administered (1 mg/mL ZnFe2O4) in X BalbC mice and were compared as contrast agents in magnetic resonance imaging (MRI). After determining the r1/r2 ratio, the samples were compared to other commercially available contrast agents. Consistent with other SPION nanoparticles, our sample exhibits a concentrated presence in the hepatic region of the animals, with comparable biodistribution and pharmacokinetics suspected. Moreover, a small dose of 1.3 mg/body weight kg was found to be sufficient for effective imaging. It should also be noted that no toxic side effects were observed, making ZnFe2O4-NH2 advantageous for pharmaceutical formulations.

Evidence characterising skills, competencies and policies in advanced practice critical care nursing in Europe: a scoping review protocol

INTRODUCTION

The management of critically ill patients is challenged by increasing population age and prevalence of comorbid diseases. High-quality intensive care nursing practice is imperative to accommodate these issues. The roles of the nurse practitioner (NP) and the acute care NP have existed for decades in the USA, Canada and Australia but are still evolving in Europe. Some European countries have introduced the advanced practice nurse (APN), but the current standard of the advanced level of nursing is variable and consensus regarding the framework, role and definition is lacking. Literature and evidence are sparse as well. Identification of skills and competencies required for the APN is warranted. Mapping skills and competencies will enable future educational harmonisation and facilitate mobility of the advanced-level intensive care nursing workforce across Europe. The aim of our scoping review is to identify literature describing skills, competencies and policies characterising advanced nursing practice in intensive care across Europe.

METHODS AND ANALYSIS

We will apply a five-stage scoping review methodology with a comprehensive systematic literature search as outlined by Arksey and O'Malley. In collaboration with a research librarian, we will search nine interdisciplinary databases and grey literature for publications originating in European countries in 1992-2018. Using a two-stage screening process with Covidence to remove duplicates, we will first scan the title and abstract and then perform full-text review to determine the eligibility of the papers. Qualitative content analysis will be used to chart the data.

ETHICS AND DISSEMINATION

Our study is a part of the European Union-funded INACTIC project (International Nursing Advanced Competency-based Training for Intensive Care) with the overall aim of developing a common European curriculum for advanced practice critical care nursing. Results from this scoping review mapping the evidence of APNs in Europe will be presented at national and international conferences and published in a peer-reviewed journal.