Surface plasmon resonance biosensing: Approaches for screening and characterising antibodies for food diagnostics

Abstract

Research in biosensing approaches as alternative techniques for food diagnostics for the detection of chemical contaminants and foodborne pathogens has increased over the last twenty years. The key component of such tests is the biorecognition element whereby polyclonal or monoclonal antibodies still dominate the market. Traditionally the screening of sera or cell culture media for the selection of polyclonal or monoclonal candidate antibodies respectively has been performed by enzyme immunoassays. For niche toxin compounds, enzyme immunoassays can be expensive and/or prohibitive methodologies for antibody production due to limitations in toxin supply for conjugate production. Automated, self-regenerating, chip-based biosensors proven in food diagnostics may be utilised as rapid screening tools for antibody candidate selection. This work describes the use of both single channel and multi-channel surface plasmon resonance (SPR) biosensors for the selection and characterisation of antibodies, and their evaluation in shellfish tissue as standard techniques for the detection of domoic acid, as a model toxin compound. The key advantages in the use of these biosensor techniques for screening hybridomas in monoclonal antibody production were the real time observation of molecular interaction and rapid turnaround time in analysis compared to enzyme immunoassays. The multichannel prototype instrument was superior with 96 analyses completed in 2 h compared to 12 h for the single channel and over 24 h for the ELISA immunoassay. Antibodies of high sensitivity, IC50's ranging from 4.8 to 6.9 ng/mL for monoclonal and 2.3–6.0 ng/mL for polyclonal, for the detection of domoic acid in a 1 min analysis time were selected. Although there is a progression for biosensor technology towards low cost, multiplexed portable diagnostics for the food industry, there remains a place for laboratory-based SPR instrumentation for antibody development for food diagnostics as shown herein.

The benefits of carbon black, gold and magnetic nanomaterials for point-of-harvest electrochemical quantification of domoic acid

“…For these assays, a monoclonal anti-domoic acid antibody was used. This antibody showed no crossreactivity towards naturally co-occurring toxins and compounds similar to DA that co-occur in shellfish in previous experiments [22,23]. This being said, to determine the selectivity of the biosensor, possible interference caused by various marine toxins and DA similar compounds was equally tested here.…”

“…Selectivity of the biosensor for DA against the co-occurring marine toxins saxitoxin (STX), neosaxitoxin (NEO), gonyautoxin-2 (GTX-2), okadaic acid (OA) and tetrodotoxin (TTX) was tested. Additionally, the compounds L-glutamic acid (GA), L-glutamine (GluNH2), aspartic acid (Asp.A) and L-ascorbic acid (L-AA), which are structurally similar to DA and are usually present in shellfish tissue [22,23,27], was tested for their interference as well. A detailed description of the method used can be found in the supplementary material section 2.8.…”

A Self-Referenced Diffraction-Based Optical Leaky Waveguide Biosensor Using Photofunctionalised Hydrogels

“…The contributions of analyte binding and common-mode effects can be separated by referencing [ 18 , 19 , 20 ] where typically differential measurements between the outputs of the sensor and reference regions are performed. Commercial instruments such as BIACORE have multiple fluidic channels where at least one of the channels is used for referencing [ 18 ]. The use of multiple fluidic channels often results in solutions reaching the sensor and reference channels at slightly different times, resulting in spikes in the differential signal.…”

Aflatoxin-specific Monoclonal Antibody Selection for Immunoaffinity Column Development

“…mAb selection process should be considered in a broad perspective, starting from laboratory performance of the antibody to commercial production costs of the system. Specificity and affinity are the initial criteria used for the selection of the desired antibody [10,14,15]. Beyond that, a new set of criteria should be established for every analyte and every immunoanalytical system to be considered [12,16].…”