Spacer length and serum protein adsorption affect active targeting of trastuzumab-modified nanoparticles.

Receptor-mediated active targeting of nanocarriers is a widely investigated approach to specifically address cancerous cells and tissues in the human body. The idea is to use these formulations as drug carriers with enhanced specificity and therefore reduced systemic side effects. Until today a big obstacle to reach this goal remains the adsorption of serum proteins to the nanocarrier's surface after contact with biological fluids. In this context different nanoparticle characteristics could be beneficial for effective active targeting after formation of a protein corona which need to be identified. In this study trastuzumab was used as an active targeting ligand which was covalently attached to human serum albumin nanoparticles. For coupling reaction different molecular weight spacers were used and resulting physicochemical nanoparticle characteristics were evaluated. The in vitro cell association of the different nanoparticle formulations was tested in cell culture experiments with or without fetal bovine serum. For specific receptor-mediated cell interaction SK-BR-3 breast cancer cells with human epidermal growth factor receptor 2 (HER2) overexpression were used. MCF-7 breast cancer cells with normal HER2 expression served as control. Furthermore, serum protein adsorption on respective nanoparticles was characterized. The qualitative and quantitative composition of the protein corona was analyzed by SDS-PAGE and LC-MS/MS and the influence of protein adsorption on active targeting capability was determined.

Erratum to 'Spacer length and serum protein adsorption affect active targeting of trastuzumab-modified nanoparticles' [Biomaterials and Biosystems 5 (2022) 100032].

[This corrects the article DOI: 10.1016/j.bbiosy.2021.100032.].

Actuation of Flexible Membranes via Capillary Force: Single-Active-Surface Experiments.

Conventional approaches to microscale actuation, such as electrostatic, have difficulty in achieving large motion at moderate voltages. Recently, actuators relying on the active control of capillary pressure have been demonstrated, with the pressure change caused by electrowetting on a pair of opposing surfaces. In this work, experimental results are presented from five prototype devices in which only a single active surface is used. The results demonstrate that pressure changes induced in a liquid bridge in this manner can produce large deflections (15 µm) of a flexible membrane. Voltages employed in the tests were moderate (≤25 V). The influence of several design variables, such as membrane diameter and thickness, on the membrane deflection are examined. Theoretical predictions are also presented and generally follow the experimental values. Potential sources for the discrepancies between theory and experimental results are discussed. While deflections obtained using a single active surface are not as large as those obtained with two active surfaces, single-active-surface configurations offer a simple route to achieving adequate deflections for lab-on-a-chip microsystems.

[Leadership and communication]. / Kommunikation und Führung.

Medical leadership requires specific communication skills in order to meet professional demands. Communicative behaviour is usually highly automated and not necessarily conscious. Managerial communication competes against elaborated but not role-specific behaviour patterns, especially in critical situations. Accordingly, competent medical leadership requires the awareness of individual communication habits as well as the knowledge and ability to use conversation techniques suitable for a specific situational context. The training of leadership-related communication techniques requires the de-automation of existing skills and a problem-oriented construction and re-automation of new communication techniques.