Simultaneous determination of four different antibiotic residues in honey by chemiluminescence multianalyte chip immunoassays

The Simultaneous Detection of Multiple Antibiotics in Milk and Pork Based on an Antibody Chip Biosensor

In the modern farming industry, the irrational or illegal use of veterinary drugs leads to residues in animal-derived food, which can seriously threaten human health. Efficient detection of low concentrations of drug residues in animal products in a short time is a key challenge for analytical methods. This study proposes to use an antibody chip biosensor for rapid and automated analysis of cephalosporins, aminoglycosides, and sulfonamide antibiotics in pork and milk. 3D polymer slides were applied for the preparation of antibody chips. Ovalbumin (OVA) or bovine serum albumin (BSA) conjugates of the haptens were immobilized as spots on disposable chips. Monoclonal antibodies (mAbs) against cefalexin, ceftiofur, gentamicin, neomycin, and sulfonamides allowed the simultaneous detection of the respective analytes. Antibody binding was detected by a second antibody labeled with Cy3-generating fluorescence, which was scanned a with chip scanner. The limits of detection (LOD) for all the analytes were far below the respective maximum residue limits (MRLs) and ranged from 0.51 to 4.3 µg/kg. The average recoveries of all the analytes in each sample were in the range of 81.6–113.6%. The intra- and inter-assay CV was less than 12.9% and showed good accuracy and precision for all the antibiotics at the MRL level. The sample pretreatment method is simple, and the results are confirmed to be accurate by LC–MS/MS; therefore, this method is valuable for the quality control of animal-derived food.

Validation of two UHPLC-MS/MS methods for fast and reliable determination of quinolone residues in honey

Antibiotic usage for beekeeping, including quinolones, can lead to residues in honey and these residues usually result from the drugs used in the treatment of American or European foulbrood diseases. Residues in honey may cause allergic reactions as well as increased antibiotic resistance. Within this study, rapid and breakthrough analysis methods were developed using UHPLC-ESI-MS/MS and sample preparation processes were minimised. Practical, low cost, time-effective analysis was provided utilising 'dilute & shoot' methodology and a QuEChERS-based procedure has been developed alternatively for improved sensitivity. Recovery values were 85%-112% for the 'dilute & shoot' method, and 82%-117% for the modified QuEChERS method. For accuracy studies, RSD% values were between 0.7% and 13.4% for both methods in intra-day and inter-day precision studies. CCα (1.1 μg/kg and 0.6 μg/kg) and CCβ (1.2 μg/kg and 0.6 μg/kg) mean values were calculated for the 'dilute & shoot' and QuEChERS method, respectively. These novel methods achieved simultaneous quantification of 21 quinolones in 7 min with high specificity and were used to analyse 50 honey samples. Quinolone residues were found in samples, and enrofloxacin, danofloxacin, pipemidic acid, lomefloxacin, cinoxacin, and ciprofloxacin were quantified.

Flow-based regenerable chemiluminescence receptor assay for the detection of tetracyclines

For the first time, a flow-based regenerable chemiluminescence receptor assay is established that is eminently suited as screening method for the detection of widely used tetracyclines (TCs) in environmental and food samples. The complex functionality and high reactivity of TCs complicate the creation of immunogens which is currently the bottleneck for developing sensitive immunoassays. In this case, competitive bioreceptor assays for the analysis of small organic molecules are preferable and, moreover, flow-based regenerable bioassays are optimally suited for automated analysis applications. Therefore, the solution for rapid and sensitive analysis of TCs is the regenerable CL receptor assay with a covalently immobilized DNA oligonucleotide containing the specific operator sequence tetO to which the repressor protein TetR binds only in the absence of TCs. The TC measurements are performed on the CL microarray analysis platform MCR 3 within 30 min per sample. The LoD in spiked tap water was determined to be 0.1 μg L⁻¹, and for 1 μg L⁻¹ TET, recoveries of 77% ± 16% were obtained. Due to the stability of the immobilized DNA oligonucleotide and the resulting regenerability of the assay for various measurements, the new method is highly cost- and resource-efficient and ideally suited for the monitoring of environmental samples in the field.

Production of generic monoclonal antibody and development of chemiluminescence immunoassay for determination of 32 sulfonamides in chicken muscle

A hapten of sulfabenzamide was first synthesized to generate a monoclonal antibody that simultaneously recognized 32 sulfonamides. The computational simulation showed that the 3D conformation, molecular bend angle, molecular volume, electronic charge of core structure of these drugs all showed influences on the antibody binding. The antibody was combined with a heterologous enzyme-labeled hapten to develop a direct competitive chemiluminescence enzyme linked immunosorbent assay for determination of the 32 sulfonamides in chicken muscle sample. The CRs of the optimized method for these drugs were in the range of 7.3%-1778%, and the IC₅₀ values were in the range of 0.038-11.2 ng/g. The limits of detection for detection of these drugs in chicken were in the range of 0.03-26 ng/g. Their recoveries from the standards fortified blank chicken samples were in the range of 60.8%-97.1%. Therefore, this method could be used as a useful tool for routine screening sulfonamides residues in meat.

Study of solvent effect on the synthesis of magnetic molecularly imprinted polymers based on ultrasound probe: Application for sulfonamide detection

In this work, a comparative study of the effect of various solvents on the synthesis of magnetic molecularly imprinted polymers (MMIPs) based on the use of high-power ultrasound probe is reported for the first time. Dimethylsulfoxide (DMSO), dimethylformamide (DMF), ethanol, acetonitrile and acetone were studied as solvents for the synthesis of MMIPs. Several crucial experimental conditions such as the time of synthesis and the applied amplitude were investigated. DMSO, DMF and ethanol were successfully used for ultrasound-assisted synthesis of MMIPs. However, for the polymerization performed using acetonitrile and acetone, no significant conversion to product was observed. Under optimal conditions for each solvent tested, the synthesized MMIPs were characterized using several techniques such as Scanning/Transmission Electron Microscopy (SEM and STEM modes), X-Ray Diffraction, Fourier Transform Infra-Red Spectroscopy, Thermal Gravimetric Analysis and Vibrating Sample Magnetometer system. The study of adsorption time of MMIPs showed that fast adsorption occurred due to the presence of specific imprinted sites on the surface. Moreover, isotherm study showed that the experimental equilibrium data fitted well with Freundlich model. The results of selectivity study indicated that MMIPs could selectively recognize the target molecule. Due to its high adsorption properties and easiness of preparation, MMIP-DMSO was used successfully as adsorbent material in solid-phase extraction coupled to a colorimetric method for sulfamethoxazole (SMX). After optimizing analytical conditions, a calibration plot was performed in the concentration range from 0.2 to 5 µg·mL^-1 with limits of detection and quantitation of 0.06 and 0.2 µg·mL^-1, respectively. The developed procedure was applied successfully for SMX determination in spiked tap and mineral waters showing satisfactory recoveries. Besides, reusability study demonstrated that MMIP could be reused at least 8 times keeping good binding capacity.

Determination of sulfonamides in meat with dummy-template molecularly imprinted polymer-based chemiluminescence sensor

In this study, a molecularly imprinted polymer capable of recognizing 15 sulfonamides was first synthesized with sulfabenz as the dummy template. The calculation results from computation simulation showed that the specific 3D conformation of the template had an important influence on the polymer's recognition ability. Then, the polymer was used as recognition reagent to prepare a chemiluminescence sensor on a conventional 96-well microplate for the determination of the residues of 15 sulfonamides in meat (chicken and pork). Due to the 4-(imidazol-1-yl)phenol-enhanced luminol-H₂O₂ system, the limits of detection for the 15 analytes were in the range of 1.0-12 pg/mL. The recoveries from the standard fortified blank samples were in the range of 72.7-99%. Furthermore, one assay could be finished within 30 min, and the sensor could be reused 4 times. Therefore, this sensor could be used as a very useful tool for routine screening of residues of sulfonamides in meat samples. Graphical abstract Assay procedures of the molecularly imprinted polymer-based chemiluminescence sensor for determination of sulfonamides.

Simultaneous Quantitative Detection of Six Families of Antibiotics in Honey Using A Biochip Multi-Array Technology

Chemical residues of veterinary drugs such as streptomycin, chloramphenicol, macrolides, sulphonamides, tetracyclines, quinolones and aminoglycosides and other contaminants such as pesticides and heavy metals have been found in honey, leading to concerns for human health. Indeed, there is a growing interest in their presence and persistence in the environment because low levels of antibiotics may favour the proliferation of antibiotic-resistant bacteria. Moreover, antibiotics present in honey may produce residues in foodstuffs, causing adverse effects on humans such as allergic reactions, toxic effects and damage to the central nervous systems. For food and health/safety reasons, antibiotic drugs are not authorized for the treatment of honey bees in the EU, even though these antimicrobial drugs have been approved in many third-party countries. For this reason, contaminated honey products can still be found in European markets. Therefore, there is a need to develop a precise, accurate and sensitive analytical method that may be used to simply and rapidly detect these compounds in honey. The aim of our study was to detect the presence of antibiotics in Apulian honey using the Anti-Microbial array II (AM II) as an innovative screening method to test the health quality of honey and honey products.

A genetically engineered Escherichia coli that senses and degrades tetracycline antibiotic residue

Due to the abuse of antibiotics, antibiotic residues can be detected in both natural environment and various industrial products, posing threat to the environment and human health. Here we describe the design and implementation of an engineered Escherichia coli capable of degrading tetracycline (Tc)-one of the commonly used antibiotics once on humans and now on poultry, cattle and fisheries. A Tc-degrading enzyme, TetX, from the obligate anaerobe Bacteroides fragilis was cloned and recombinantly expressed in E. coli and fully characterized, including its K m and k cat value. We quantitatively evaluated its activity both in vitro and in vivo by UV-Vis spectrometer and LC-MS. Moreover, we used a tetracycline inducible amplification circuit including T7 RNA polymerase and its specific promoter PT7 to enhance the expression level of TetX, and studied the dose-response of TetX under different inducer concentrations. Since the deployment of genetically modified organisms (GMOs) outside laboratory brings about safety concerns, it is necessary to explore the possibility of integrating a kill-switch. Toxin-Antitoxin (TA) systems were used to construct a mutually dependent host-plasmid platform and biocontainment systems in various academic and industrious situations. We selected nine TA systems from various bacteria strains and measured the toxicity of toxins (T) and the detoxifying activity of cognate antitoxins (A) to validate their potential to be used to build a kill-switch. These results prove the possibility of using engineered microorganisms to tackle antibiotic residues in environment efficiently and safely.

Aptamer based fluorometric sulfamethazine assay based on the use of graphene oxide quantum dots

The authors have developed a homogeneous "off-on" fluorometric method for the determination of the antibiotic sulfamethazine (SMZ). Aptamer against SMZ was labeled with graphene oxide quantum dots upon which the Graphene oxide quenched the blue fluorescence of the GOQDs. On addition of SMZ, the aptamers will bind SMZ and this will cause the release of GOQDs. As a result, fluorescence will be regenerated. Fluorescence, best measured at excitation/emission wavelengths of 365/455 nm, increases linearly in the 8 pg·mL^-1 to 60 ng·mL^-1 SMZ concentration range, with a 5 pg·mL^-1 detection limit. The method is reliable and was successfully applied to the determination of SMZ in spiked milk samples, with recoveries ranging from 89 to 96% depending on analyte concentration. Graphical abstract Graphene oxide quantum dots (GOQDs) were covalently bound to the aptamer (apt) against sulfamethazine (SMZ) and adsorbed on the surface of graphene oxide (GO). This results in quenching of the fluorescence of GOQDs. On addition of SMZ, fluorescence is restored due to the release of GOQD@apt from GO.

Feasibility of a novel multispot nanoarray for antibiotic screening in honey

Practical solutions for multiple antibiotic determination in food are required by the food industry and regulators for cost-effective screening purposes. This study describes the feasibility in development and preliminary performance of a novel multispot nanoarray for antibiotic screening in honey. Using a multiplex approach, the metabolites of the four main nitrofuran antibiotics, including morpholinomethyl-2-oxazolidone (AMOZ), 3-amino-2-oxazolidinone (AOZ), semicarbazide (SEM), 1-aminohydantoin (AHD) and chloramphenicol (CAP), were simultaneously detected. Antibodies specific to the five antibiotics were nano-spotted onto microtitre plate wells and a direct competitive assay format was employed. The assay characteristics and performance were evaluated for feasibility as a screening tool for antibiotic determination in honey to replace traditional ELISAs. Optimisation of the spotting and assay parameters was undertaken with both individual and multiplex calibration curves generated in PBS and a honey matrix. The limits of detection as determined by the 20% inhibitory concentrations (IC₂₀) were determined as 0.19, 0.83, 0.09, 15.2 and 35.9 ng ml^-1 in PBS, 0.34, 0.87, 0.17, 42.1 and 90.7 ng ml^-1 in honey (fortified at the start of the extraction), and 0.23, 0.98, 0.24, 24.8 and 58.9 ng ml^-1 in honey (fortified at the end of the extraction) for AMOZ, AOZ, CAP, SEM and AHD respectively. This work has demonstrated the potential of multiplex analysis for antibiotics with results available for 40 samples within a 90-min period for antibiotics sharing a common sample preparation. Although both the SEM and AHD assay do not show the required sensitivity with the antibodies available for use to meet regulatory limits, with further improvements in these particular antibodies this multiplex format has the potential to show a reduction in cost with reduced labour time in combination with the high-throughput screening of samples. This is the first 96-well spotted microtitre plate nanoarray for the semi-quantitative and simultaneous analysis of antibiotics.

Validation Procedure for Multiplex Antibiotic Immunoassays Using Flow-Based Chemiluminescence Microarrays

Small molecules like antibiotics or other pharmaceuticals can be detected and quantified, among others, with indirect competitive immunoassays. With regard to multiplex quantification, these tests can be performed as chemiluminescence microarray immunoassays, in which, in principle, the analyte in the sample and the same substance immobilized on the chip surface compete for a limited number of specific antibody binding sites. The amount of the specific primary antibody that has been bound to the surface is visualized by means of a chemiluminescence reaction.Validated quantitative confirmatory methods for the detection of contaminants, for example drug residues, in food samples usually comprise chromatographic analysis and spectrometric detection, e.g., HPLC-MS, GC-MS, or GC with electron capture detection. Here, we describe a validation procedure (according to the Commission Decision of the European Communities 2002/657/EC) for multiplex immunoassays performed as flow-through chemiluminescence microarrays, using the example of a small molecule microarray for the simultaneous detection of 13 antibiotics in milk. By this means, we suggest to accept multianalyte immunoassays as confirmatory methods as well, to benefit from the advantages of a fast automated method that does not need any pretreatment of the sample. The presented microarray chip is regenerable, so an internal calibration is implemented. Therefore, the analytical results are highly precise, combined with low costs (the aim for commercialization is less than 1 € per analyte per sample, this is significantly less than HPLC-MS).

On-Chip Isothermal Nucleic Acid Amplification on Flow-Based Chemiluminescence Microarray Analysis Platform for the Detection of Viruses and Bacteria

This work presents an on-chip isothermal nucleic acid amplification test (iNAAT) for the multiplex amplification and detection of viral and bacterial DNA by a flow-based chemiluminescence microarray. In a principle study, on-chip recombinase polymerase amplification (RPA) on defined spots of a DNA microarray was used to spatially separate the amplification reaction of DNA from two viruses (Human adenovirus 41, Phi X 174) and the bacterium Enterococcus faecalis, which are relevant for water hygiene. By establishing the developed assay on the microarray analysis platform MCR 3, the automation of isothermal multiplex-amplification (39 °C, 40 min) and subsequent detection by chemiluminescence imaging was realized. Within 48 min, the microbes could be identified by the spot position on the microarray while the generated chemiluminescence signal correlated with the amount of applied microbe DNA. The limit of detection (LOD) determined for HAdV 41, Phi X 174, and E. faecalis was 35 GU/μL, 1 GU/μL, and 5 × 10(3) GU/μL (genomic units), which is comparable to the sensitivity reported for qPCR analysis, respectively. Moreover the simultaneous amplification and detection of DNA from all three microbes was possible. The presented assay shows that complex enzymatic reactions like an isothermal amplification can be performed in an easy-to-use experimental setup. Furthermore, iNAATs can be potent candidates for multipathogen detection in clinical, food, or environmental samples in routine or field monitoring approaches.

A microfluidic device for the automated electrical readout of low-density glass-slide microarrays

Microarrays are a powerful platform for rapid and multiplexed analysis in a wide range of research fields. Electrical readout systems have emerged as an alternative to conventional optical methods for microarray analysis thanks to its potential advantages like low-cost, low-power and easy miniaturization of the required instrumentation. In this work an automated electrical readout system for low-cost glass-slide microarrays is described. The system enables the simultaneous conductimetric detection of up to 36 biorecognition events by incorporating an array of interdigitated electrode transducers. A polydimethylsiloxane microfluidic structure has been designed that creates microwells over the transducers and incorporates the microfluidic channels required for filling and draining them with readout and cleaning solutions, thus making the readout process fully automated. Since the capture biomolecules are not immobilized on the transducer surface this readout system is reusable, in contrast to previously reported electrochemical microarrays. A low-density microarray based on a competitive enzymatic immunoassay for atrazine detection was used to test the performance of the readout system. The electrical assay shows a detection limit of 0.22±0.03 μg L(-1) similar to that obtained with fluorescent detection and allows the direct determination of the pesticide in polluted water samples. These results proved that an electrical readout system such as the one presented in this work is a reliable and cost-effective alternative to fluorescence scanners for the analysis of low-density microarrays.

Regeneration of recombinant antigen microarrays for the automated monitoring of antibodies against zoonotic pathogens in swine sera

The ability to regenerate immobilized proteins like recombinant antigens (rAgs) on surfaces is an unsolved problem for flow-based immunoassays on microarray analysis systems. The regeneration on microarray chip surfaces is achieved by changing the protein structures and desorption of antibodies. Afterwards, reactivation of immobilized protein antigens is necessary for reconstitution processes. Any backfolding should be managed in a way that antibodies are able to detect the protein antigens in the next measurement cycle. The regeneration of rAg microarrays was examined for the first time on the MCR3 flow-based chemiluminescence (CL) microarray analysis platform. The aim was to reuse rAg microarray chips in order to reduce the screening effort and costs. An antibody capturing format was used to detect antibodies against zoonotic pathogens in sera of slaughtered pigs. Different denaturation and reactivation buffers were tested. Acidic glycine-SDS buffer (pH 2.5) and 8 M guanidinium hydrochloride showed the best results in respect of denaturation efficiencies. The highest CL signals after regeneration were achieved with a carbonate buffer containing 10 mM DTT and 0.1% BSA for reactivation. Antibodies against Yersinia spp. and hepatitis E virus (HEV) were detected in swine sera on one immunochip over 4 days and 25 measurement cycles. Each cycle took 10 min for detection and regeneration. By using the rAg microarray chip, a fast and automated screening of antibodies against pathogens in sera of slaughtered pigs would be possible for zoonosis monitoring.

Identification of the target binding site of ethanolamine-binding aptamers and its exploitation for ethanolamine detection

Aptamers are promising recognition elements for sensitive and specific detection of small molecules. We have previously selected ssDNA aptamers for ethanolamine, one of the smallest aptamer targets so far. The work presented here focuses on the determination of the binding region within the aptamer structure and its exploitation for the development of an aptamer-based assay for detection of ethanolamine. Sequence analysis of the aptamers resulted in the identification of a G-rich consensus sequence, which was able to fold in a typical two- or three-layered G-quartet structure. Experiments with stepwise truncated variants of the aptamers revealed that the consensus sequence is responsible and sufficient for binding to the target. On the basis of the knowledge of the aptamers binding site, we developed an aptamer-based microarray assay relying on competition between ethanolamine and an oligonucleotide complementary to the consensus sequence. Competitive binding of ethanolamine and fluorescently labeled complementary oligonucleotides resulted in fluorescence intensities dependent on ethanolamine concentration with a limit of detection of 10 pM. This method enables detection of small molecules without any labeling of analytes. The competitive assay could potentially be transferred to other aptamers and thus provides a promising system for aptamer-based detection of diverse small molecules.

Cloning, expression, purification and characterization of a bispecific single-chain diabody against fluoroquinolones and sulfonamides in Escherichia coli

A recombinant bispecific single-chain diabody (scDb), recognizing fluoroquinolones (FQs) and sulfonamides (SAs), was successfully constructed with two single-chain variable fragment antibodies (scFvs). The scDb gene was cloned into the expression vector pJB33, and 6×His-tagged scDb was expressed as soluble bodies in Escherichia coli RV308 host, then purified by one step affinity chromatography of immobilized metal ion affinity chromatography (IMAC). SDS-PAGE and Western blotting analysis of the purified scDb indicated that the prepared scDb was successfully expressed as a ∼60 kDa and the final purity of the scDb protein was up to 95% with yields of approximately 6 mg/L of bacterial culture. The scDb was further characterized by indirect competitive enzyme linked immunosorbent assay (icELISA), showing that the affinity and specificity of scDb were fully retained from the two parental scFvs, capable of simultaneously binding FQs and SAs. The 50% inhibition concentration (IC50) values of the optimized immunoassay were 0.45 ng mL(-1) for FQs and 0.75 ng mL(-1) for SAs, respectively. The scDb exhibited high affinity to 20 FQs and 14 SAs. Taken together, these findings suggested that the prepared scDb could be used to develop future novel immunoassay for simultaneous determination of 20 FQs and 14 SAs.

Oligonucleotide microarray chip for the quantification of MS2, ΦX174, and adenoviruses on the multiplex analysis platform MCR 3

Pathogenic viruses are emerging contaminants in water which should be analyzed for water safety to preserve public health. A strategy was developed to quantify RNA and DNA viruses in parallel on chemiluminescence flow-through oligonucleotide microarrays. In order to show the proof of principle, bacteriophage MS2, ΦX174, and the human pathogenic adenovirus type 2 (hAdV2) were analyzed in spiked tap water samples on the analysis platform MCR 3. The chemiluminescence microarray imaging unit was equipped with a Peltier heater for a controlled heating of the flow cell. The efficiency and selectivity of DNA hybridization could be increased resulting in higher signal intensities and lower cross-reactivities of polymerase chain reaction (PCR) products from other viruses. The total analysis time for DNA/RNA extraction, cDNA synthesis for RNA viruses, polymerase chain reaction, single-strand separation, and oligonucleotide microarray analysis was performed in 4-4.5 h. The parallel quantification was possible in a concentration range of 9.6 × 10(5)-1.4 × 10(10) genomic units (GU)/mL for bacteriophage MS2, 1.4 × 10(5)-3.7 × 10(8) GU/mL for bacteriophage ΦX174, and 6.5 × 10(3)-1.2 × 10(5) for hAdV2, respectively, by using a measuring temperature of 40 °C. Detection limits could be calculated to 6.6 × 10(5) GU/mL for MS2, 5.3 × 10(3) GU/mL for ΦX174, and 1.5 × 10(2) GU/mL for hAdV2, respectively. Real samples of surface water and treated wastewater were tested. Generally, found concentrations of hAdV2, bacteriophage MS2, and ΦX174 were at the detection limit. Nevertheless, bacteriophages could be identified with similar results by means of quantitative PCR and oligonucleotide microarray analysis on the MCR 3.

Immunoassays and biosensors for the detection of cyanobacterial toxins in water

Algal blooms are a frequent phenomenon in nearly all kinds of fresh water. Global warming and eutrophication by waste water, air pollution and fertilizers seem to lead to an increased frequency of occurrence. Many cyanobacteria produce hazardous and quite persistent toxins, which can contaminate the respective water bodies. This may limit the use of the raw water for many purposes. The purification of the contaminated water might be quite costly, which makes a continuous and large scale treatment economically unfeasible in many cases. Due to the obvious risks of algal toxins, an online or mobile detection method would be highly desirable. Several biosensor systems have been presented in the literature for this purpose. In this review, their mode of operation, performance and general suitability for the intended purpose will be described and critically discussed. Finally, an outlook on current developments and future prospects will be given.

New route for fast detection of antibodies against zoonotic pathogens in sera of slaughtered pigs by means of flow-through chemiluminescence immunochips

The research on fast screening methods for antibodies against zoonotic pathogens in slaughter animals is important for food safety in farming and meat-processing industries. As a proof-of-concept study, antibodies against the emerging zoonotic pathogen hepatitis E virus (HEV) and enteropathogenic Yersinia spp. were analyzed in parallel using immobilized recombinant antigens (rAgs) of HEV genotypes 1 and 3 and Yersinia outer protein D (YopD) on a flow-through chemiluminescence immunochip. These rAgs are usually part of commercially available line immunoassays (LIAs) used for human diagnostics. In this study, sera from slaughtered pigs were tested on the microarray analysis platform MCR 3 to detect anti-HEV and anti-Yersinia IgG. The new method was characterized regarding signal reproducibility and specificity. The analytical performance was compared with in-house enzyme-linked immunosorbent assay (ELISA) and a LIA based on recomLine HEV (Mikrogen) or the ELISA test kit pigtype Yersinia Ab (Qiagen), respectively. The immunochip revealed the highest analytical sensitivity and was processed in 9 min automatically on the MCR 3. A comparative screening of swine serum samples from Bavarian slaughterhouses regarding anti-HEV and anti-Yersinia IgG seroprevalence was conducted. By using the LIA, 78% of the sera were tested positive for HEV antibodies. The immunochip and the ELISA identified anti-HEV IgG in 96% and 93% of the tested samples using the O2C-gt1 and O2C-gt3 rAg, respectively. The screening for anti-Yersinia IgG resulted in 86% positive findings using the immunochip and 57% and 48% for the ELISA methods, respectively, indicating a higher detection capability of the new method. Serum samples of slaughtered pigs could be analyzed faster and in an automated way on the microarray analysis platform MCR 3 which shows the great potential of the new immunochip assay format for multiplexed serum screening purposes.