BIA Separations (Slovenia)

About: BIA Separations (Slovenia) is a company organization based out in Ljubljana, Slovenia. It is known for research contribution in the topics: Monolithic HPLC column & Monolith. The organization has 84 authors who have published 152 publications receiving 4883 citations.

Chromatographic Monoliths for High-Throughput Immunoaffinity Isolation of Transferrin from Human Plasma

Abstract: Changes in protein glycosylation are related to different diseases and have a potential as diagnostic and prognostic disease biomarkers. Transferrin (Tf) glycosylation changes are common marker for congenital disorders of glycosylation. However, biological interindividual variability of Tf N-glycosylation and genes involved in glycosylation regulation are not known. Therefore, high-throughput Tf isolation method and large scale glycosylation studies are needed in order to address these questions. Due to their unique chromatographic properties, the use of chromatographic monoliths enables very fast analysis cycle, thus significantly increasing sample preparation throughput. Here, we are describing characterization of novel immunoaffinity-based monolithic columns in a 96-well plate format for specific high-throughput purification of human Tf from blood plasma. We optimized the isolation and glycan preparation procedure for subsequent ultra performance liquid chromatography (UPLC) analysis of Tf N-glycosylation and managed to increase the sensitivity for approximately three times compared to initial experimental conditions, with very good reproducibility. This work is licensed under a Creative Commons Attribution 4.0 International License .

Depletion of human serum albumin in embryo culture media for in vitro fertilization using monolithic columns with immobilized antibodies

Abstract: Affinity depletion of abundant proteins such as HSA is an important stage in routine sample preparation prior to MS/MS analysis of biological samples with high range of concentrations. Due to the charge competition effects in electrospray ion source that results in discrimination of the low-abundance species, as well as limited dynamic range of MS/MS, restricted typically by three orders of magnitude, the identification of low-abundance proteins becomes a challenge unless the sample is depleted from high-concentration compounds. This dictates a need for developing efficient separation technologies allowing fast and automated protein depletion. In this study, we performed evaluation of a novel immunoaffinity-based Convective Interaction Media analytical columns (CIMac) depletion column with specificity to HSA (CIMac-αHSA). Because of the convective flow-through channels, the polymethacrylate CIMac monoliths afford flow rate independent binding capacity and resolution that results in relatively short analysis time compared with traditional chromatographic supports. Seppro IgY14 depletion kit was used as a benchmark to control the results of depletion. Bottom-up proteomic approach followed by label-free quantitation using normalized spectral indexes were employed for protein quantification in G1/G2 and cleavage/blastocyst in vitro fertilization culture media widely utilized in clinics for embryo growth in vitro. The results revealed approximately equal HSA level of 100 ± 25% in albumin-enriched fractions relative to the nondepleted samples for both CIMac-αHSA column and Seppro kit. In the albumin-free fractions concentrated 5.5-fold by volume, serum albumin was identified at the levels of 5-30% and 20-30% for the CIMac-αHSA and Seppro IgY14 spin columns, respectively.

Multiple-Monitor HPLC Assays for Rapid Process Development, In-Process Monitoring, and Validation of AAV Production and Purification.

Abstract: HPLC is established as a fast convenient analytical technology for characterizing the content of empty and full capsids in purified samples containing adeno-associated virus (AAV). UV-based monitoring unfortunately over-estimates the proportion of full capsids and offers little value for characterizing unpurified samples. The present study combines dual-wavelength UV monitoring with intrinsic fluorescence, extrinsic fluorescence, and light-scattering to extend the utility of HPLC for supporting development of therapeutic AAV-based drugs. Applications with anion exchange (AEC), cation exchange (CEC), and size exclusion chromatography (SEC) are presented. Intrinsic fluorescence increases sensitivity of AAV detection over UV and enables more objective estimation of empty and full capsid ratios by comparison of their respective peak areas. Light scattering enables identification of AAV capsids in complex samples, plus semiquantitative estimation of empty and full capsid ratios from relative peak areas of empty and full capsids. Extrinsic Picogreen fluorescence enables semiquantitative tracking of DNA with all HPLC methods at all stages of purification. It does not detect encapsidated DNA but reveals DNA associated principally with the exteriors of empty capsids. It also enables monitoring of host DNA contamination across chromatograms. These enhancements support many opportunities to improve characterization of raw materials and process intermediates, to accelerate process development, provide rapid in-process monitoring, and support process validation.

Semi-high-throughput isolation and N-glycan analysis of human fibrinogen using monolithic supports bearing monoclonal anti-human fibrinogen antibodies.

Abstract: Fibrinogen (FIB) is a secretory glycoprotein synthesized by hepatocytes that has a key role in blood clotting. Its glycosylation has not been studied in detail and little is known about the biological variability of FIB N-glycosylation, mainly due to the lack of fast, simple, and robust approaches to purify FIB from blood plasma samples. In recent years, customised chromatographic monoliths have been used for a variety of biological applications due to their unique characteristics. Here we describe development and optimisation of monolithic supports bearing monoclonal anti-human fibrinogen antibodies in a single column as well as in multi-well plate formats with high FIB specificity and binding capacity for fast immunoaffinity purification of FIB from human blood samples. The developed semi-high-throughput workflow has been successfully applied for FIB immunoaffinity isolation and subsequent ultra performance liquid chromatography N-glycosylation analysis in ten healthy human individuals, demonstrating the potential of monolithic supports in glycomics studies.