Unspecific Binding Research Articles

Cell organelles and fluorescence of parenchyma cells in Eucalyptus bosistoana sapwood and heartwood investigated by microscopy

BackgroundEucalyptus bosistoana is currently investigated in New Zealand for its potential to produce naturally durable timber in short-rotation plantations. Little is known of heartwood formation in young trees. The objective of this study was to identify conventional and confocal microscopy methods which allow the observation of cell organelles and the chemical composition in the E. bosistoana parenchyma cells before and after heartwood formation.ResultsNuclei, microtubules and peroxisomes in parenchyma cells of 2-year-old E. bosistoana stems were visualised by confocal microscopy combined with optimised immunolabelling protocols. Sequential staining of the tissue with toluidine blue and iodine/potassium iodide identified different cell organelles in parenchyma cells of sapwood. Iodine/potassium iodide stained starch (amyloplasts), while amido black stained proteins in sapwood. Fluorescence emission spectra confirmed the presence of chloroplasts in parenchyma of 2-year-old E. bosistoana. Fluorescence emission spectral (lambda) scans showed differences between parenchyma and fibre cells as well as sapwood and heartwood.ConclusionsPhysiological changes between sapwood and heartwood were visualised in parenchyma cells. Labelling of cell organelles was challenging due to unspecific binding and high background signals. Understanding heartwood formation is critical for the success of a plantation forest industry aiming to produce ground-durable timber, as heartwood formation is variable.

SPME Extraction Methods of Doped Organochlorine Pesticides in Moroccan Water Samples

To investigate Organochlorine (OC) in Moroccan water samples, two different methods of extraction being the solid phase micro extraction (SPME) and the liquid-liquid extraction (LLE) are exploited. The gas chromatography with an electron capture detector (GC-ECD) and the gas chromatography coupled to a mass spectrum (GC-MS) are elaborated. In order to get the best extraction, different process parameters are cheeked and optimized. The relevant results are obtained using a time of unspecific binding properties of 30 minutes’ duration and mode of agitation for 30 min with agitation by a magnetic stirrer and a temperature of 30 °C. In particular, a comparative study between the results of SPME and LLE coupled to (GC-ECD) and (GC-MS), respectively, are given. Concretely, it has been found that the SPME extraction technique is a very useful method to analyze the pesticide residues in water samples controlled by local laboratories.

Curcumin in combination with anti-cancer drugs: A nanomedicine review.

A huge surge of research is being conducted on combination therapy with anticancer compounds formulated in the form of nanoparticles (NPs). Numerous advantages like dose minimalization and synergism, reversal of multi drug resistance (MDRs), enhanced efficacy have emerged with nanoencapsulation of chemotherapeutic agents with chemo-sensitizing agent like curcumin. Within last couple of years various nano-sized formulations have been designed and tested both in vitro with cell lines for different types of cancers and in vivo with cancer types and drug resistance models. Despite the combinatorial models being advanced, translation to human trials has not been as smooth as one would have hoped, with as few as twenty ongoing clinical trials with curcumin combination, with less than 1/10th being nano-particulate formulations. Mass production of nano-formulation based on their physico-chemical and pharmacokinetics deficits poses as major hurdle up the ladder. Combination of these nano-sized dosage with poorly bioavailable drugs, unspecific target binding ability and naturally unstable curcumin further complicates the formulation aspects. Emphasis is now therefore being laid on altering natural forms of curcumin and usage of formulations like prodrug or coating of curcumin to overcome stability issues and focus more on enhancing the pharmaceutical and therapeutic ability of the nano-composites. Current studies and futuristic outlook in this direction are discussed in the review, which can serve as the basis for upcoming research which could boost commercial translational of improved nano-sized curcumin combination chemotherapy.

Spy and Snoop protein superglues for nano-assembly and tickling the immune system

Cadherin-2 plays a fundamental role during zebrafish CNS and heart morphogenesis. Profiling zCdh2 expression via antibody staining is essential to achieving better understanding of its role during zebrafish development. Generation of recombinant human antibodies to zCdh2 by phage display was used to identify monoclonal antibodies with reduced unspecific binding patterns when compared to available commercial antibodies. Specificity was profiled using flow cytometry of wild type, zCdh2-defective mutant and zCdh2-GFP zebrafish cells. The epitopes recognized by the novel antibodies were mapped to peptides located in the first or second extracellular domains of zCdh2. These antibodies allowed improved observations of the spatial distribution of zCdh2 from imaging of whole mount zebrafish preparations. Since the generated antibodies are sequence defined, they can always be reconstituted from the information stored in the respective computer file, securing future reproducibility of respective experiments. The results further suggest that sequence defined antibodies with specificities thoroughly controlled by flow cytometry and genetic antigen-defective mutants or knockouts can substantially reduce the risk of misleading, false-positive results in whole mount imaging and other assays, and thus can improve the scientific value of such assays.

Oral delivery of alternative protein scaffold Nanofitins targeting TNFα shows a strong anti-inflammatory effect in models of inflammatory bowel diseases

Cadherin-2 plays a fundamental role during zebrafish CNS and heart morphogenesis. Profiling zCdh2 expression via antibody staining is essential to achieving better understanding of its role during zebrafish development. Generation of recombinant human antibodies to zCdh2 by phage display was used to identify monoclonal antibodies with reduced unspecific binding patterns when compared to available commercial antibodies. Specificity was profiled using flow cytometry of wild type, zCdh2-defective mutant and zCdh2-GFP zebrafish cells. The epitopes recognized by the novel antibodies were mapped to peptides located in the first or second extracellular domains of zCdh2. These antibodies allowed improved observations of the spatial distribution of zCdh2 from imaging of whole mount zebrafish preparations. Since the generated antibodies are sequence defined, they can always be reconstituted from the information stored in the respective computer file, securing future reproducibility of respective experiments. The results further suggest that sequence defined antibodies with specificities thoroughly controlled by flow cytometry and genetic antigen-defective mutants or knockouts can substantially reduce the risk of misleading, false-positive results in whole mount imaging and other assays, and thus can improve the scientific value of such assays.

Bumepamine, a brain-permeant benzylamine derivative of bumetanide, does not inhibit NKCC1 but is more potent to enhance phenobarbital's anti-seizure efficacy

Based on the potential role of Na-K-Cl cotransporters (NKCCs) in epileptic seizures, the loop diuretic bumetanide, which blocks the NKCC1 isoforms NKCC1 and NKCC2, has been tested as an adjunct with phenobarbital to suppress seizures. However, because of its physicochemical properties, bumetanide only poorly penetrates through the blood-brain barrier. Thus, concentrations needed to inhibit NKCC1 in hippocampal and neocortical neurons are not reached when using doses (0.1–0.5 mg/kg) in the range of those approved for use as a diuretic in humans. This prompted us to search for a bumetanide derivative that more easily penetrates into the brain. Here we show that bumepamine, a lipophilic benzylamine derivative of bumetanide, exhibits much higher brain penetration than bumetanide and is more potent than the parent drug to potentiate phenobarbital's anticonvulsant effect in two rodent models of chronic difficult-to-treat epilepsy, amygdala kindling in rats and the pilocarpine model in mice. However, bumepamine suppressed NKCC1-dependent giant depolarizing potentials (GDPs) in neonatal rat hippocampal slices much less effectively than bumetanide and did not inhibit GABA-induced Ca2+ transients in the slices, indicating that bumepamine does not inhibit NKCC1. This was substantiated by an oocyte assay, in which bumepamine did not block NKCC1a and NKCC1b after either extra- or intracellular application, whereas bumetanide potently blocked both variants of NKCC1. Experiments with equilibrium dialysis showed high unspecific tissue binding of bumetanide in the brain, which, in addition to its poor brain penetration, further reduces functionally relevant brain concentrations of this drug. These data show that CNS effects of bumetanide previously thought to be mediated by NKCC1 inhibition can also be achieved by a close derivative that does not share this mechanism. Bumepamine has several advantages over bumetanide for CNS targeting, including lower diuretic potency, much higher brain permeability, and higher efficacy to potentiate the anti-seizure effect of phenobarbital.

Pathomechanism of mutated and secreted retinoschisin in X-linked juvenile retinoschisis

Mutations in the RS1 gene encoding retinoschisin cause X-linked juvenile retinoschisis (XLRS), a hereditary retinal dystrophy in males. While most of the XLRS associated mutations strongly interfere with cellular secretion, this is not true for mutants RS1-F108C, -R141G, -R141H, -R182C, -H207Q and -R209H. Native retinoschisin builds double-octamers and binds to retinal membranes, interacting with the retinal Na/K-ATPase. Functionally, it regulates MAP kinase signaling and Na/K-ATPase localization, and hampers photoreceptor degeneration. In this study, we investigated the capacity of the retinoschisin mutants still secreted extracellularly to fulfil these tasks.We addressed secretion and oligomerization of the heterologously expressed mutants as well as their binding to recombinant retinal Na/K-ATPases and murine retinoschisin-deficient (Rs1h-/Y) retinal and non-retinal explants. This has refined the categorization of secreted retinoschisin mutants: (i) no octamerization, unspecific membrane binding (RS1-F108C and -R182C), (ii) double-octamerization but no membrane binding (RS1-R141H), and (iii) double-octamerization and unspecific membrane binding (RS1-R141G, -H207Q, and -R209H). Notably, selected mutants of all categories (RS1-F108C, -R141H, and -R209H) failed to regulate retinal MAP kinase signaling and Na/K-ATPase localization in Rs1h-/Y retinal explants, and could not attenuate photoreceptor degeneration. Bioinformatic modeling of the secreted mutants depicted prominent alterations in the spatial and temporal conformation of a substructure called “spike 3” and its vicinity, implying a crucial role of this substructure for binding capacity and specificity.Taken together, our data point to a pathomechanism for secreted retinoschisin mutants, specifically to disturbances of the retinoschisin interface accompanied by unphysiological membrane interactions and impaired regulatory functions.

Modulating receptor-ligand binding in biorecognition by setting surface wettability.

Modulation of support wettability used for microarray format biosensing has led to an improvement of results. Hydrophobicity of glass chips was set by derivatizing with single vinyl organosilanes of different chain length and silane mixtures. Thiol-ene photochemical linking has been used as effective chemistry for covalent anchoring of thiolated probes. Lowest unspecific binding and highest signal intensity and SNR were obtained with large hydrocarbon chain (C22) silanes or a shorter one (C10) containing fluorine atoms. SNR resulting values are improved, reaching levels higher than 1500 in some cases, when using vinyl silanes modified with 1% C10 alkyl fluorinated one, because mild hydrophobicity was achieved (water contact angle ca. 110°) for all silanes, including the short C2 and C3, thus giving rise to smaller and better defined array spots. In addition, unspecific binding of reagents and targets was totally withdrawn. Hence, good-performing surfaces for biosensing applications can be built using appropriate organosilane reagent selection, including fluorinated ones. Graphical abstract ᅟ.

Theoretical Design of an Integrated Optical Sensor for a Standard Immunoassay

Immunoassay is a biochemical test that measures the presence or concentration of biomolecule in a solution by the means of the antibody (or antigen). Most immunoassays involve chemically linking antibodies or antigens with some kind of detectable labels which produce measurable signals in response to the binding. The use of labels creates problems, including complexity in the screening process and probable influence on the nature of target molecular. To overcome the drawbacks, we theoretically demonstrate an integrated Mach–Zehnder interferometer (MZI) with $n$ -shaped slot waveguide based on finite-element method. Dual polarization can be strongly confined in the slot where the analytes are accommodated. The interaction between the optical field and tested solution is greatly enhanced, resulting in high sensitivity of the device. The detection of surface adsorbed molecule densities is down to 0.176pg/mm2 for transverse electric mode and 1.27pg/mm2 for transverse magnetic mode. The integrated MZI with identical configuration of both arms make the parallel-control trial available thereby effectively preventing the unspecific binding and background from biological materials. Wavelength interrogation was taken to monitor the antibody-antigen recognition.

Design of an integrated optics for transglutaminase conformational change

Abstract A detailed theoretical research on a novel integrated optics with surface plasmon resonance (SPR)-based waveguide is presented. An SPR multilayer section is designed by introducing intermediate layers to support fundamental mode and stronger electromagnetic field. Most current techniques excited with a single optical mode are “blind” to the conformational change of bound molecules. The greatest strength of such technique lies in monitoring protein conformational change. The Mach-Zehnder interferometry architecture is adopted to maximize sensor sensitivity and prevent unspecific binding from biological material and error from geometrical difference. A proof-of-concept is conducted on the integrated optics by detecting protein transglutaminase (tTG) specifically binding calcium ion (Ca2+) via the finite-element method. The minimum decrease of biolayer thickness (δa =0.5 nm) caused by tTG-Ca2+ interaction is much smaller than a single protein molecule (normally 1–100 nm). Associated with biolayer thickness and density, a thin dense layer is formed as Ca2+ binds to the tTG protein. Thus, the tTG protein undergoing conformational change on binding Ca2+ is traced and verified as molecular interaction occurs.

Investigations on the binding of ethylmercury from thiomersal to proteins in influenza vaccines

This study investigates the binding of ethylmercury (EtHg+) released from the preservative thiomersal by hydrolysis to proteins in influenza vaccines via ultrafiltration and subsequent total reflection x-ray fluorescence (TXRF) analysis as well as size exclusion chromatography (SEC) hyphenated to inductively coupled plasma-mass spectrometry (ICP-MS).Binding of EtHg+ to the protein fraction was shown by means of ultrafiltration and TXRF in a qualitative matter. SEC/ICP-MS was applied to gain more information about the molecular weight of the bound protein and quantitative information. First experiments showed the necessity of a rinsing step during elution with a thiol-containing compound to prevent unspecific binding or mercury species to the chromatographic system. Adduct formation of EtHg+ and a high-molecular compound could be observed for different concentrations of EtHg+ applied. The mercury-containing fraction was larger than 133 kDa, indicating binding to hemagglutinin, which is the active ingredient in influenza vaccines. The applied SEC/ICP-MS method allowed for external calibration with EtHg+ and a binding of 141 μg L−1 Hg was shown for a vaccine solution that was incubated with EtHg+ (25 mg L−1 Hg).

Transcription factor target site search and gene regulation in a background of unspecific binding sites

Response time and transcription level are vital parameters of gene regulation. They depend on how fast transcription factors (TFs) find and how efficient they occupy their specific target sites. It is well known that target site search is accelerated by TF binding to and sliding along unspecific DNA and that unspecific associations alter the occupation frequency of a gene. However, whether target site search time and occupation frequency can be optimized simultaneously is mostly unclear. We developed a transparent and intuitively accessible state-based formalism to calculate search times to target sites on and occupation frequencies of promoters of arbitrary state structure. Our formalism is based on dissociation rate constants experimentally accessible in live cell experiments. To demonstrate our approach, we consider promoters activated by a single TF, by two coactivators or in the presence of a competitive inhibitor. We find that target site search time and promoter occupancy differentially vary with the unspecific dissociation rate constant. Both parameters can be harmonized by adjusting the specific dissociation rate constant of the TF. However, while measured DNA residence times of various eukaryotic TFs correspond to a fast search time, the occupation frequencies of target sites are generally low. Cells might tolerate low target site occupancies as they enable timely gene regulation in response to a changing environment.

Insights into the binding behavior of native and non-native cytochromes to photosystem I from Thermosynechococcus elongatus

The binding of photosystem I (PS I) from Thermosynechococcus elongatus to the native cytochrome (cyt) c6 and cyt c from horse heart (cyt cHH) was analyzed by oxygen consumption measurements, isothermal titration calorimetry (ITC), and rigid body docking combined with electrostatic computations of binding energies. Although PS I has a higher affinity for cyt cHH than for cyt c6, the influence of ionic strength and pH on binding is different in the two cases. ITC and theoretical computations revealed the existence of unspecific binding sites for cyt cHH besides one specific binding site close to P700 Binding to PS I was found to be the same for reduced and oxidized cyt cHH Based on this information, suitable conditions for cocrystallization of cyt cHH with PS I were found, resulting in crystals with a PS I:cyt cHH ratio of 1:1. A crystal structure at 3.4-Å resolution was obtained, but cyt cHH cannot be identified in the electron density map because of unspecific binding sites and/or high flexibility at the specific binding site. Modeling the binding of cyt c6 to PS I revealed a specific binding site where the distance and orientation of cyt c6 relative to P700 are comparable with cyt c2 from purple bacteria relative to P870 This work provides new insights into the binding modes of different cytochromes to PS I, thus facilitating steps toward solving the PS I-cyt c costructure and a more detailed understanding of natural electron transport processes.

Enhanced Selectivity by Passivation: Molecular Imprints for Viruses with Exceptional Binding Properties.

Inspired by the recognition processes found in biology such as enzyme-substrate and antibody-antigen interactions, synthetic systems with comparable molecular recognition properties have been investigated during recent years based on molecular imprinting strategies. While materials with recognition capabilities for small molecules (i.e., with low molecular weight) have achieved substantial advancements, the synthesis of molecularly imprinted materials with virus recognition properties remains challenging to date. Likewise, protein-surface and protein-protein interactions are essential for a wide variety of biological applications in biotechnology. In biological sensor technology the coating of surfaces to prevent nonspecific adsorption interactions plays an important role. Particularly, polyethylene glycol (PEG) stands out for its high performance in preventing proteins from nonspecifically interactions. However, blocking agents such as the protein bovine serum albumin (BSA) can also be useful as unspecific binding prevention agents for passivation, without modification of the surface. Herein the influence of blocking agents as unspecific reaction components is investigated on the enhancements of selectivity from adenovirus-imprinted particles, whereas adenovirus was used as target species in molecular imprinting. Furthermore, quantitative polymerase chain reaction (qPCR) was used for the first time as virus quantification approach in this context.

Development of Safe and Non-Self-Immunogenic Mucosal Adjuvant by Recombinant Fusion of Cholera Toxin A1 Subunit with Protein Transduction Domain.

Potential use of cholera toxin (CT) as a mucosal vaccine adjuvant has been documented in a variety of animal models. However, native CT is highly toxic to be used as a mucosal adjuvant in humans. Here, we demonstrate a new approach to generate a mucosal adjuvant by replacing the B subunit of CT with HIV-1 Tat protein transduction domain (PTD), which efficiently delivers fusion proteins into the cell cytoplasm by unspecific binding to cell surface. We compared the adjuvanticity and toxicity of Tat PTD-CTA1-Tat PTD (TCTA1T) with those of CT. Our results indicate that intranasal (i.n.) delivery of ovalbumin (OVA) with TCTA1T significantly augments the OVA-specific systemic and mucosal antibody responses to levels comparable to those seen with CT adjuvant. Moreover, in vivo cytotoxic T lymphocyte activity elicited by TCTA1T was significantly higher than that elicited by a mutant TCTA1T (TmCTA1T) lacking ADP-ribosyltransferase function. In addition, coadministration of influenza M2 protein with TCTA1T conferred near complete protection against lethal influenza virus challenge. Importantly, TCTA1T, in contrast to CT, did not induce serum IgG antibody responses to itself and was shown to be nontoxic. These results suggest that TCTA1T may be a safe and effective adjuvant when given by mucosal routes.

Sequence defined antibodies improve the detection of cadherin 2 (N-cadherin) during zebrafish development

Cadherin-2 plays a fundamental role during zebrafish CNS and heart morphogenesis. Profiling zCdh2 expression via antibody staining is essential to achieving better understanding of its role during zebrafish development. Generation of recombinant human antibodies to zCdh2 by phage display was used to identify monoclonal antibodies with reduced unspecific binding patterns when compared to available commercial antibodies. Specificity was profiled using flow cytometry of wild type, zCdh2-defective mutant and zCdh2-GFP zebrafish cells. The epitopes recognized by the novel antibodies were mapped to peptides located in the first or second extracellular domains of zCdh2. These antibodies allowed improved observations of the spatial distribution of zCdh2 from imaging of whole mount zebrafish preparations. Since the generated antibodies are sequence defined, they can always be reconstituted from the information stored in the respective computer file, securing future reproducibility of respective experiments. The results further suggest that sequence defined antibodies with specificities thoroughly controlled by flow cytometry and genetic antigen-defective mutants or knockouts can substantially reduce the risk of misleading, false-positive results in whole mount imaging and other assays, and thus can improve the scientific value of such assays.

The Cu2+-nitrilotriacetic acid complex improves loading of α-helical double histidine site for precise distance measurements by pulsed ESR

Site-directed spin labeling using two strategically placed natural histidine residues allows for the rigid attachment of paramagnetic Cu2+. This double histidine (dHis) motif enables extremely precise, narrow distance distributions resolved by Cu2+-based pulsed ESR. Furthermore, the distance measurements are easily relatable to the protein backbone-structure. The Cu2+ ion has, till now, been introduced as a complex with the chelating agent iminodiacetic acid (IDA) to prevent unspecific binding. Recently, this method was found to have two limiting concerns that include poor selectivity towards α-helices and incomplete Cu2+-IDA complexation. Herein, we introduce an alternative method of dHis-Cu2+ loading using the nitrilotriacetic acid (NTA)-Cu2+ complex. We find that the Cu2+-NTA complex shows a four-fold increase in selectivity toward α-helical dHis sites. Furthermore, we show that 100% Cu2+-NTA complexation is achievable, enabling precise dHis loading and resulting in no free Cu2+ in solution. We analyze the optimum dHis loading conditions using both continuous wave and pulsed ESR. We implement these findings to show increased sensitivity of the Double Electron-Electron Resonance (DEER) experiment in two different protein systems. The DEER signal is increased within the immunoglobulin binding domain of protein G (called GB1). We measure distances between a dHis site on an α-helix and dHis site either on a mid-strand or a non-hydrogen bonded edge-strand β-sheet. Finally, the DEER signal is increased twofold within two α-helix dHis sites in the enzymatic dimer glutathione S-transferase exemplifying the enhanced α-helical selectivity of Cu2+-NTA.

Interactions of Protonated Guanidine and Guanidine Derivatives with Multiply Deprotonated RNA Probed by Electrospray Ionization and Collisionally Activated Dissociation.

Interactions of ribonucleic acid (RNA) with guanidine and guanidine derivatives are important features in RNA–protein and RNA–drug binding. Here we have investigated noncovalently bound complexes of an 8‐nucleotide RNA and six different ligands, all of which have a guanidinium moiety, by using electrospray ionization (ESI) and collisionally activated dissociation (CAD) mass spectrometry (MS). The order of complex stability correlated almost linearly with the number of ligand atoms that can potentially be involved in hydrogen‐bond or salt‐bridge interactions with the RNA, but not with the proton affinity of the ligands. However, ligand dissociation of the complex ions in CAD was generally accompanied by proton transfer from ligand to RNA, which indicated conversion of salt‐bridge into hydrogen‐bond interactions. The relative stabilities and dissociation pathways of [RNA+m L−n H]n− complexes with different stoichiometries (m=1–5) and net charge (n= 2–5) revealed both specific and unspecific ligand binding to the RNA.

Development of a Multifunctional Nanobiointerface Based on Self-Assembled Fusion-Protein rSbpA/ZZ for Blood Cell Enrichment and Phenotyping.

We present a multifunctional nanobiointerface for blood cell capture and phenotyping applications that features both excellent antifouling properties and high antibody activity. Multifunctionality is accomplished by modifying polymeric materials using self-assembled S-layer fusion-protein rSbpA/ZZ to immobilize high density antibodies at the two protein A binding sites of the rSbpA/ZZ nanolattice structure. Controlled orientation and alignment of the antibodies reduced antibody consumption 100-fold and increased cell capture efficiency 4-fold over standard methodologies. Cell analysis in complex samples was made possible by the remarkable antifouling properties of the rSbpA domain, while at the same time reducing unspecific binding and forgoing tedious blocking procedures. An automated microfluidic in situ cell analysis platform for isolation and phenotyping of primary peripheral blood mononuclear cells was developed as practical application. Results obtained using our automated microfluidic cell analysis platform showed that the multifunctional nanobiointerface can discriminate among T helper and cytotoxic T cells, and thymocytes. Additionally, on-chip cell capture under flow conditions using a high affinity CD 3 selective nanobiointerface preferentially isolated cells with strong surface marker expression. This means that our dynamic microfluidic cell purification method allows the enrichment of 773 CD 8 positive cytotoxic T cells out of a total blood cell population of 7728 PBMCs, which is an increase in cell enrichment of 8-fold with a purity of 85%.

Microchip capillary gel electrophoresis combined with lectin affinity enrichment employing magnetic beads for glycoprotein analysis

Due to the constant search for reliable methods to investigate glycoproteins in complex biological samples, an alternative approach combining affinity enrichment with rapid and sensitive analysis on-a-chip is presented. Glycoproteins were specifically captured by lectin-coated magnetic beads, eluted by competitive sugars, and investigated with microchip capillary gel electrophoresis (MCGE), i.e., CGE-on-a-chip. We compared our results to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) data, which turned out to be in very good agreement. While SDS-PAGE offers the possibility of subsequent mass spectrometric analysis of captured and separated analytes, MCGE scores with time savings, higher throughput, and lower sample consumption as well as quality control (QC) and process analytical technology (PAT) applicability. Due to these advantages, a lectin-based glycoprotein capture protocol can easily be optimized. In our case, two different types of magnetic beads were tested and compared regarding lectin binding. The selectivity of our strategy was demonstrated with a set of model glycoproteins, as well as with human serum and serum depleted from high-abundance proteins. The specificity of the capturing method was investigated revealing to a certain degree an unspecific binding between each sample and the beads themselves, which has to be considered for any specific enrichment and data interpretation. In addition, two glycoproteins from Trichoderma atroviride, a fungus with mycoparasitic activity and only barely studied glycoproteome, were enriched by means of a lectin and so identified for the first time.Graphical abstractGlycoproteins from biological samples were detected by microchip capillary gel electrophoresis after lectin affinity enrichment using magnetic beads and elution with respective competitive monosaccharides