Electrochemical metal speciation using self-assembled monolayers

The application of self-assembled monolayers (SAMs) as a means of achieving speciation in heavy metal electrochemical determination is demonstrated. SAMs are monomolecular organic layers that can be chemically attached onto different electrode materials and used for the selective extraction of heavy metals. The selectivity is achieved by assembling monolayers that have pendant ligands, which interact selectively with the analytes in the solution. For example, the formation of a monolayer comprising a pyridine group was used to selectively extract Cr(VI) from aqueous solutions, whereas the selective determination of Fe(II) was accomplished using a covalently bound terpyridine monolayer. Yet, determining the heterogeneous binding constants of the metallic species by the SAMs is of significant importance and allows studying quantitatively the interactions between the monolayer and the metal ions. We have developed a few methods for determining the binding constants of heavy metal ions by SAMs of which two of them are briefly discussed here

Characterization of a PEGylated protein therapeutic by ion exchange chromatography with on-line detection by native ESI MS and MS/MS

Detailed profiling of both enzymatic (e.g., glycosylation) and non-enzymatic (e.g., oxidation and deamidation) post-translational modifications (PTMs) is frequently required for the quality assessment of protein-based drugs.</p

MitraClip therapy in patients with acute severe mitral regurgitation

Abstract Background There is a lack of data to support the optimal management of high-risk patients with acute severe mitral regurgitation (MR). The role of the MitraClip implantation in treatment of acute severe mitral regurgitation (MR) is undetermined. Methods We screened all patients who underwent MitraClip implantation at the Hadassah Medical Center between October 2015 and December 2019. We evaluated immediate, 30-day and 1-year outcomes after the procedure. We evaluated patients with severe MR due to ruptured cord because of degenerative disease and acute-on-chronic functional MR due to ischemic (after a recent myocardial infarction (MI)) or non-ischemic etiology (secondary to decompensated HF). Results From a cohort of 151 patients, who underwent MitraClip implantation in our center, we identified 35 patients (23.2%) with acute severe mitral regurgitation (4+) and decompensated refractory heart failure. Patients' mean age was 74.15 years, 66.9% - were males. One, 2, or 3 clips were implanted. Reduction of MR from 4+ to 1+ was achieved in 34 patients (66.7%). Twenty-eight patients (80%) had acute-on-chronic severe MR and refractory heart failure including 6 cases after recent MI, other 7 patients presented with heart failure and acute severe MR secondary to ruptured cord due to degenerative disease. After MitraClip implantation, reduction of MR severity was achieved in all patients. Seven patients were withdrawn from intravenous therapy and intra-aortic balloon pump 2–3 days after the procedure. Four patients died during hospitalization, three of them due to sepsis. 30-day follow-up showed improvement of NYHA functional class and a tendency toward improvement in left ventricle systolic function with signs of reverse remodeling. Nevertheless, we observed high 30-day and 1-year mortality rate (11.4 and 23.8% respectively). Conclusions MitraClip therapy could be an alternative option for treatment of patients with acute and acute-on-chronic severe MR of ischemic and non-ischemic etiology. Funding Acknowledgement Type of funding source: None </jats:sec