Paper accepted: Quantification of chitosan in aqueous solutions by enzymatic hydrolysis and oligomer analysis via HPLC-ELSD

Today, Philipp Schröder’s and Dr. Stefan Cord-Landwehr’s paper on an improved method for the quantification of chitosan was accepted for publication in the high-ranking journal Carbohydrate Polymers. It is really surprising that reliable methods for quantification of chitosan in solution are rare. So many researchers are purchasing chitosan from some supplier and use it without questioning its quality and purity. And admittedly, we have also focused on quality more than on purity in the past, assuming that our chitosan producers, such as Dr. Dominique Gillet from the French company Gillet Chitosan or Dr. Katja Richter from the German company Heppe Medical Chitosan, would supply us with pure chitosan samples. We routinely purify such samples from insoluble (a crucial step when working with polysaccharides such as chitosans which tend to firmly aggregate during storage), but assumed that the soluble part would be pure chitosan. We were not so sure, though, when working with chitosans from other suppliers less well known to us. This is why Jasper had the idea to develop a robust method for the quantification of chitosans in solution, based on our enzymatic mass spectrometric fingerprinting (EMS-FP) analysis of chitosans. Philipp, who is pursuing his doctoral project in the Institute for Physical Chemistry of our university, under the guidance of Prof. Monika Schönhoff, took over the optimisation of this method, supported by Stefan and Dr. Cornelia Cramer, a post-doc with Monika Schönhoff, in the framework of a collaboration between our groups. Being physico-chemists, the Schönhoff group has a very rigorous way of evaluating a new method, and we have learned quite a bit in the process. When we jointly submitted the manuscript to Carbohydrate Polymers, we were extremely pleased with the rapid peer review process and the positive comments of the reviewers. Our revised and improved manuscript was then quickly accepted for publication, possibly a new record in time from submission to acceptance. And using this new method, we were (fortunately!) able to confirm the purity of chitosans from our trusted suppliers, though not of all chitosans we had obtained from others. This is the first paper in Philipp’s doctoral project, and Stefan’s first senior author paper – congratulations to both!