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Abstract: Currently there is an increasing demand for high-throughput methods to identify and to verify the potential of new drug candidates. Cell-based microelectronic biosensors might be powerful tools for rapid screening assays. However, reliable cultivation of cells is influenced by the material characteristics and the surface topography of the wafers serving as growth supports. In order to investigate the influence of micropatterned structures on cell viability, Caco-2 cells were seeded on silicon wafers featuring trench/mesa patterns obtained by lithography and reactive ion etching. Besides determination of the cell growth pattern by electron microscopic inspection, the adherence of cells on different patterned silicon wafers and the formation of the tight junctional network was investigated. Microstructured trench/mesa patterns, especially their lateral distances, remarkably influenced the adhesion and proliferation behavior of Caco-2 cells. Lateral distances below the average cell diameter were easily overgrown by the cells, whereas dimensions above the average cell diameter increasingly limited cell proliferation. Notably increased cell growth was observed using trenches with a width of 10–20μm and a trench depth of around 35μm. All in all, the results of this study might improve the production of microstructured biosensors and open up new perspectives concerning the combination of biosensors and microfluidic systems. [Copyright &y& Elsevier]

Introduction: Cytokines are basic targets that have to be removed effectively in order to improve the patient's health status in treating severe inflammation, sepsis, and septic shock. Although there are different adsorbents commercially available, the success of their clinical use is limited. Here, we tested different adsorbents for their effective removal of cytokines from plasma and the resulting effect on endothelial cell activation. Methods: The three polystyrene divinylbenzene (PS-DVB) based adsorbents Amberchrom CG161c and CG300m and a clinically approved haemoperfusion adsorbent (HAC) were studied with regard to cytokine removal in human blood. To induce cytokine release from leucocytes, human blood cells were stimulated with 1 ng/ml LPS for 4 hours. Plasma was separated and adsorption experiments in a dynamic model were performed. The effect of cytokine removal on endothelial cell activation was evaluated using a HUVEC-based cell culture model. The beneficial outcome was assessed by measuring ICAM-1, E-selectin, and secreted cytokines IL-8 and IL-6. Additionally the threshold concentration for HUVEC activation by TNF-α and IL-1β was determined using this cell culture model. Results: CG161c showed promising results in removing the investigated cytokines. Due to its pore size the adsorbent efficiently removed the key factor TNF-α, outperforming the commercially available adsorbents. The CG161c treatment reduced cytokine secretion and expression of cell adhesion molecules by HUVEC which underlines the importance of effective removal of TNF-α in inflammatory diseases. Conclusion: These results confirm the hypothesis that cytokine removal from the blood should approach physiological levels in order to reduce endothelial cell activation. [ABSTRACT FROM AUTHOR]

PLGA microparticles loaded with three different fluorescent model drugs, fluorescein sodium (hydrophilic), sulforhodamine (amphoteric), and boron- dipyrromethene (BODIPY® 493/503, lipophilic), were prepared by the solvent evaporation technique. Due to varying hydrophilicity, the diameters of the microparticles ranged between 4.1 and 4.7 µm. According to fluorimetric analysis, the loading varied from 0.06 to 2.25 µg of the model drug per mg PLGA. In terms of the release profile, the fluorescein sodium-entrapped formulation exhibited thermo-responsive release kinetics. In the case of sulforhodamine- and BODIPY® 493/503-loaded particles, almost no release was observed, neither at 4°C nor 37°C during the first 50 hours. Furthermore, to estimate the bioadhesive properties of such drug delivery systems, the surface of the loaded particles was grafted with wheat germ agglutinin by applying the carbodiimide method. Cytoadhesion studies with Caco-2 monolayers revealed an up to 1.9-fold and 3.6-fold increase in the bioadhesion of the lectin-functionalized, model drug-loaded particles as compared to the albumin- and non-grafted microcarriers, respectively. All in all, the results clearly indicated that the lipophilicity of the polymer matching that of the drug favored entrapment, whereas mismatching impeded loading into the PLGA-microparticles. Even in the case of low loading, these delivery systems might be useful for the fluorescent detections and microscopic imaging of cellular interactions due to their fluorescent properties and lack of dye leakage. Moreover, lectin grafting can mediate bioadhesive properties to such particulate drug carriers which could be a promising approach to improve drug delivery. [ABSTRACT FROM AUTHOR]

Objective. The aim of this work was the development of appropriate analytical methods and assays for determining and monitoring composition and degradation of nanoparticles built from PLGA (poly D, L-lactid-co-glycolid), which can be reloaded with different drugs. A sensitive and precise method for monitoring of nanoparticle degradation in vitro was developed and optimized. Nanoparticles allow a selective enrichment of different drugs and knowledge of the nature and type of their degradation is essential for characterization and control of drug release and dosage. Materials and methods. The first method developed during this work to quantify the PLGA polymer matrix use advantage of the chemical reaction of aliphatic carboxylic acids with ferric chloride (FeCl3) thus quantifying both degradation products of PLGA, lactic and glycol acids, at the same time. A second assay method of choice was to react to the polymer hydrolysate with lactate dehydrogenase, thus assaying selectively the lactic acid part. Results. During development of both of described methods was possible to determine dynamic range for PLGA matrix and nanoparticles, as well as to characterize impact of Pluronic F-68 and glycolic acid on lactate dehydrogenase activity. Conclusion. During our work we were able to develop two sensitive methods for monitoring of biodegradation of polymers which are consecutively used as a nanoparticle matrix in drug targeting. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this project was to develop a rectal formulation of metyrapone suitable for application in an infant hospitalised with McCune-Albright syndrome (MAS)-related Cushing syndrome and to provide a detailed description of the formulation protocol including quality control parameters., Methods: Suppositories with a drug load of up to 100 mg metyrapone were prepared. Mass variation, content uniformity and drug release were analysed according to the guidelines set out by the European Pharmacopoeia. Monitoring of the drug content for 6 weeks allowed for estimation of the storage stability at 2-8°C., Results: A protocol for the reproducible preparation of suppositories with intended metyrapone content of 30-100 mg was established. The suppositories were well tolerated by the patient and the clinical outcome is promising. The suppository preparations complied with the regulations from the European Pharmacopoeia. Further, a stability of the rectal formulation of at least 1 month was confirmed, facilitating medication supply for home care., Conclusions: An adequate and easy to follow protocol for preparation of high-quality metyrapone suppositories, with sufficient stability for practical use and fulfilling major pharmaceutical quality parameters, was established. The protocol can be easily replicated by skilled personnel in a community pharmacy facilitating treatment of the infant in home care., Competing Interests: Competing interests: None declared., (© European Association of Hospital Pharmacists 2023. No commercial re-use. See rights and permissions. Published by BMJ.)