Miniaturised immobilised enzymatic reactors can be used for small scale digestion of proteins. There is need for such devices; small scale devices are used either for processing of analytical sample quantities, or as proof of concept before protein digestion at larger scale. This application note compares the performance of a flow through miniaturised immobilised enzymatic reactor (μIMER) with in-solution batch digestion of simple proteins and complex matrices. Automation of peptide analysis by coupled LC-MS is explored as an option to increase throughput. In the cases evaluated, the miniaturised immobilised enzymatic reactor offered comparative results to overnight in-solution digestion, within less than 10 minutes.
Pre-activated CIMmic™ monolithic columns with 100 μL bed volume were immobilised with trypsin from bovine pancreas. This small format allows coupling to HPLC for on-line protein digestion, as well as syringe (manual) operation of the IMER. Pre-treated samples (denatured, alkylated and ultra-filtered) are injected into the column, and the eluate (tryptic digests) are subjected to LC-ESI-MS-MS analysis for protein identification and post-translational modification (PTM) determination.
Polyclonal anti-HSA antibodies were immobilised on CIMmic™ HDZ (hydrazide chemistry, 100 μL bed volume), following an optimised protocol. This CIMmic™ α-HSA column was prepared to quantitatively remove human serum albumin (HSA), the most abundant plasma protein in humans, and obtain albumin-free samples which can be further processed.
The CIMmic™ α-HSA column is optimized to selectively bind and remove HSA from plasma; albumins from other sources are bound with low efficiency. HSA depletion is carried out in two steps: (i) a loading step in which the diluted and filtered plasma sample is loaded into the column, HSA is bound and HSA-depleted plasma is collected downstream of the column and (ii) a regeneration step in which the bound HSA is removed and the column is regenerated.
Pre-activated CIMmic™ Monolithic Columns are used as a basis for preparation of small volume affinity chromatographic columns as well as enzyme reactors. Small bed volume and flexible design makes them a powerful tool for screening purposes and immobilization protocol optimizations. Range of covalently bound ligands is wide and includes diverse set of proteins, peptides, nucleotides and other affinity ligands. The covalent nature of the bond between the ligand and matrix reduces leaching and improves stability and reusability. Reaction conditions must cater to their specific physiochemical nature.
Successful preparation of an affinity column includes a decision on the appropriate matrix chemistry and determination of an optimal immobilization protocol. Presented case study explores the basics of a coupling protocol optimization using covalent immobilization of Recombinant Prokaryotic Lectins (RPL-Gal1) on CIMmic CDI-0.1 and CIMmic ALD-0.1 columns, as an example. Carboxy imidazole (CDI) and aldehyde (ALD) activated CIMmic™ columns are used for covalent immobilization of amine or thiol containing molecules.
CIMmic™ Monolithic Columns combine the advantages of the CIM® stationary phase with a flexible design and the possibility to operate with syringe. Discs containing the stationary phase can be easily interchanged inside the custom designed housing. Pre-activated chemistries enable immobilisation of numerous ligands and can be used for preparation of affinity chromatographic columns or enzyme reactors. Their small bed volume is particularly suitable for screening purposes and to optimise immobilisation protocols due to economic usage of often expensive ligands.
Carboxy imidazole (CDI) monolithic chromatographic columns are used for covalent immobilisation of proteins, peptides and other amine or thiol containing molecules. The covalent nature of the carbamate bond between the ligand and matrix reduces leaching and improves stability and reusability.
An example described below shows the feasibility of CIMmic™ CDI-0.1 utilisation for covalent immobilisation of recombinant protein A (r-pA). Additionally the example was used for the evaluation of the reproducibility of CIMmic™ CDI columns. The dynamic binding capacity for human polyclonal immunoglobulin (IgG) was used as metric for comparison of the affinity columns.
Coupling trypsin enzyme onto chromatographic supports provides a platform to reuse the enzyme and automate the hydrolysis process. A monolithic chromatographic support, such as Convective Interaction Media (CIM®), enables mass transfer of molecules within its channels exclusively by convective flow. This results in enzymatic conversion which is not limited by diffusion, making CIM® monoliths ideal for the preparation of immobilised monolith enzymatic reactors (IMERs). BIA Separations offers CIMac™ trypsin IMER with a bed volume of 0.1 mL as analytical platform for mass spectrometry (MS)-based proteomics. Larger volume IMERs (up to 80 mL) are available for industrial scale production of protein hydrolysates. The following example describes the enzymatic production of β-Lactoglobulin (β-Lg) hydrolysates using monoliths with 2 μm (N1) or 6 μm (N2) average channel diameter.
Bottom-up proteomic approach based on tandem mass spectrometry (MS/MS) is a method of choice for identification and quantitation of proteins in the complex biological samples. Followed by quantitative analysis of a protein sample, this approach enables the identification of putative biomarkers for early pathology diagnostics and differentiation. The main challenges confronting this analysis are suppression of low-abundance ions and the limited dynamic range of MS/MS.
Affinity depletion of abundant proteins is an important stage in routine sample preparation prior to tandem mass spectrometry (MS/MS) analysis of biological samples. One such protein is Human Serum Albumin (HSA). In this study, polyclonal αHSA antibodies were immobilised onto a chromatography support to use as immunoaffinity-based column (CIMac™ HDZ -αHSA) for HSA depletion from embryo culture media for in vitro fertilization (IVF).
As an alternative to conventional particle-packed columns for liquid chromatography, CIM® monolithic supports can be used.1-3 They are extremely permeable and allow very efficient mass transport at low back pressures and good separation efficiency at high flow rates. Consequently, the time of chromatographic separation can be shortened. Such characteristics are very valuable in speciation analysis where preservation of the integrity of individual chemical species of a given element is of crucial importance.4,5 CIM® monolithic disks can be placed together in one housing forming so-called conjoint liquid chromatography (CLC), which combines two different chromatographic modes in one step.
For better understanding of anticancer therapy with Pt-based chemotherapeutics, the quality of pharmaceutical formulations must be assured and the behaviour of the drugs studied by separation and detection of the intact drug and its individual biotransformation species in clinical samples at therapeutically relevant levels. To study the interactions of Pt-based chemotherapeutics with serum proteins, two-dimensional chromatographic separation of serum proteins was suggested, combining size-exclusion and CIM DEAE monolithic.6 Since this procedure is time consuming the potential of the use of CLC was investigated.
Monoclonal antibody (mAb) charge variants have gained considerable attention in the biotechnology industry, due to their potential influence on stability and biological activity of the active pharmaceutical. Cation-exchange chromatography (CEX) is historically one of the typical approaches for mAb purification and characterization, especially charge variant analysis. We have proven the flow independent separation of mAb charge variants using CIMac COOH monolithic column in a pH gradient. In this way, a resolution comparable to classical CEX particulate-based analytical columns was achieved in only 6 min analysis time. Therefore a CIMac COOH column is a perfect choice for fast Process Analytical Control (PAT) of purified mAb samples.
Transferrin (Tf) is a glycoprotein that transports iron to cells and has two N-glycosylation sites in humans – at asparagine 432 and asparagine 630. Carbohydrate-deficient Tf, which lacks one or both N-glycans, is the most common marker for congenital disorders of glycosylation.1 Altered Tf glycosylation has also been reported in hepatocellular carcinoma2 and chronic alcohol consumption.3,4 High-throughput Tf purification and glycan characterisation methods are under extensive development in order to facilitate screening of glycosylation patterns for population, genetic and clinical studies.
This application note describes the development of an immunoaffinity purification method on a CIMac™ analytical column with immobilised anti-transferrin antibodies (@Tf) and the successful transfer of the method to the monolithic 96-well plate (CIM® @Tf-0.2 monolithic 96-well plate). The affinity purification method has been used for Tf isolation from human blood plasma followed by ultra-performance liquid chromatography (UPLC) analysis of Tf N-glycosylation.
CIMac™ r-Protein A Analytical Column is a short bed, high performance monolithic column. It is intended for fast, efficient, and reproducible qualitative and quantitative analyses of Immunoglobulin G (IgG) and suitable for use with HPLC and UPLC systems. Quantification of IgG is possible between 0.2 μg and 20 μg. Its small volume and short column length allow operation at high volumetric flow rates (up to 3 mL/min). The information about product quantity and purity is thus generated in just 1 minute! The column has an innovative symmetric design for bi-directional flow contributing to longer lifetime.
The CIMacTM antibody immobilization platform enables an elegant immobilization of antibodies, which can be used as immunosorbents in specific diagnostic applications as well as in downstream processes. In this work we show the dependence of the coupling strategy on CIM monolith with the chromatographic efficiency of final immunoaffinity adsorbent. Different activation chemistries were tested for the immobilization of two model monoclonal antibodies (mAbs) with subsequent chromatographic characterization of the affinity support.
Column used for this application note were CIMac CDI, AE, EDA, HDZ, rpA.
The CIMac™ antibody immobilisation platform enables an elegant immobilisation of antibodies, which can be used as immunoaffinity adsorbents in specific diagnostic applications. Immobilization of antibodies to solid chromatographic supports is avery elegant solution for preparation of reusable immunoaffinity assays that can lower the price but also increase the accuracy and lower the limit of detection of biological assays for diagnostic purposes. Therefore, it is important that reusing a column for multiple sample analysis does not affect chromatographic/analysis performance. In this application note, an example of reusability of the hydrazide-based CIMac™ column ( HDZ ) with immobilised monoclonal antifibrinogen for consecutive purification of fibrinogen from human plasma is shown.
In diagnostic applications, fibrinogen is measured with clotting activity assay variations, together with other blood clotting factors. In research and preparative applications, larger quantities of anti-coagulants, such as EDTA and citrate, or coagulants such as Ca2+ are present in the samples, preventing successful and/or accurate fibrinogen concentration measurements. In such cases an alternative measurement method is needed.
The CIMac™ antibody immobilisation platform provides an elegant solution for immobilisation of antibodies, which are used as immunoaffinity adsorbents. It has been shown that several analytical runs can be performed on a single column. This simplicity is also combined with a fast method, where a chromatographic analysis can be completed in 4 min. Used column was hydrazide ( HDZ )-based CIMac™ column.
The demand for human normal immunoglobulin is invariably increasing on an annual basis. To satisfy increasing demands, different manufacturing processes are used to isolate immunoglobulins from human plasma. A quest for alternative paths in manufacturing not only requires development of most economical manufacturing process, but also rapid method development and development of good analytics for monitoring of manufacturing. For an efficient development of the purification methods as well as for in-process control during manufacturing stage, the uses of reliable and fast analytical techniques are crucial.
Fast and reliable fingerprint-based method for characterization of immunoglobulin G (IgG) prepared from Cohn I+II+III paste in two chromatographic steps is presented here. The fingerprint method bases on partial separation of proteins in linear gradient on CIMac™ QA 0.1 mL column. Partial separation of proteins does not allow simple quantitative analysis of the samples, however a very accurate qualitative information about the composition of the sample being analyzed can be obtained in less than 5 minutes.
Lab scale production of recombinant human monoclonal antibodies (mAbs) is required for the identification and characterization of lead clones with potential therapeutic value. For this purpose, many mAbs need to be screened. MAbs titers in this type of production scale tend to be quite low (from 0.01 – to 0.1 mg/mL), therefore a substantial amount of material needs to be processed to obtain the right amount of purified mAbs. Speed of processing and the ability to capture mAbs from diluted harvest stock are essential in this type of mAbs purification.
In this application note, a quick purification procedure using a CIM® r-Protein A-80 Tube Monolithic Column that generated up to 100 mg of mAbs with a purity of more than 95 % is described. Elution of mAbs is performed using a two-dimensional gradient (pH 7.2 to 2.5; NaCl 150 to 500 mM), allowing gentle elution of a wide range of mAbs at moderate pH (pH ~4) without any method optimization. Using this procedure, approximately 30 different mAbs were purified, processing up to 5 L of loading material (2 times diluted clarified harvest).
The demand for monoclonal antibodies is invariably increasing on an annual basis. To satisfy increasing demands, faster and cheaper ways of manufacturing are explored. A quest for alternative paths in manufacturing not only requires development of most economical manufacturing process, but also rapid method development and development of good analytics for monitoring of manufacturing. For a quickly developed process, the use of reliable and fast analytical techniques are crucial. Moreover, this analytical technique should than be preferably used also for in-process control during manufacturing stage.
Here we present fast and reliable method for processing and analyzing IgG, IgA ang IgM using CIM® QA Disk Monolithic Column, which thrive upon speed, repeatability and high capacity.
A Hemoglobin A1c reference standard was loaded on CIM® SO3 monolithic column and eluted in a mixed stepwise and linear gradient. HbA1a, HbA1b and HbA0 variants were separated and a complete determination of HbA1c (including equilibration) was obtained within 1.1 minute.
A mixture of IgG, HSA and IgM standard was loaded on CIM® EDA Disk and eluted in linear salt gradient at a flow rate of 4 mL/min (12 CV/min). A complete separation of IgM from IgG and HSA was obtained within 1.5 minute.
Immunoaffinity columns were prepared by immobilization of Protein G on CIM® Epoxy Disk, CIM® Epoxy tube (1 mL) and an activated, particle based agarose support. A comparison of productivity was performed by loading centrifuged human plasma and resulted in superior productivity of CIM® monolithic supports.