Quantitative analysis of bovine whey glycoproteins using the overall N-linked whey glycoprofile
INTERNATIONAL DAIRY JOURNAL
Authors: Valk-Weeber, Rivca L.; Eshuis-de Ruiter, Talitha; Dijkhuizen, Lubbert; van Leeuwen, Sander S.
Abstract
Bovine whey is an important ingredient in human nutrition and contains many biofunctional, glycosylated proteins. Knowledge on the glycoprotein composition of whey and whey products is valuable for the dairy industry. This paper describes a method for the characterisation of whey, or whey powders, by N-linked glycoprofile analysis. Application of the method for analysis of whey protein products showed clear differences in glycoprotein composition between concentrate, isolate and demineralised whey powders. The quantitative potential was explored by screening 100 pooled farm milk samples. IgG and lactoferrin protein concentrations determined by N-glycoprofile analysis matched well with ELISA results. The protein concentration of GIyCAM-1 was determined to be >= 1 mg mL(-1). The approaches presented in this work allow simultaneous concentration estimation of the three major whey glycoproteins, lactoferrin, IgG and GIyCAM-1 on the basis of their N-linked glycoprofiles, also in highly processed samples where conventional methods of detection (ELISA) are less suitable. (C) 2020 The Authors. Published by Elsevier Ltd.
Real-Time Nanoplasmonic Sensor for IgG Monitoring in Bioproduction
PROCESSES
Authors: Tran, Thuy; Eskilson, Olof; Mayer, Florian; Gustavsson, Robert; Selegard, Robert; Lundstrom, Ingemar; Mandenius, Carl-Fredrik; Martinsson, Erik; Aili, Daniel
Abstract
Real-time monitoring of product titers during process development and production of biotherapeutics facilitate implementation of quality-by-design principles and enable rapid bioprocess decision and optimization of the production process. Conventional analytical methods are generally performed offline/at-line and, therefore, are not capable of generating real-time data. In this study, a novel fiber optical nanoplasmonic sensor technology was explored for rapid IgG titer measurements. The sensor combines localized surface plasmon resonance transduction and robust single use Protein A-modified sensor chips, housed in a flexible flow cell, for specific IgG detection. The sensor requires small sample volumes (1-150 mu L) and shows a reproducibility and sensitivity comparable to Protein G high performance liquid chromatography-ultraviolet (HPLC-UV). The dynamic range of the sensor system can be tuned by varying the sample volume, which enables quantification of IgG samples ranging from 0.0015 to 10 mg/mL, without need for sample dilution. The sensor shows limited interference from the sample matrix and negligible unspecific protein binding. IgG titers can be rapidly determined in samples from filtered unpurified Chinese hamster ovary (CHO) cell cultures and show good correlation with enzyme-linked immunosorbent assay (ELISA).