Immunoassay
Scientist working at bench and using multichannel pipette for antibody detection.

Immunoassay: Antibody Detection

The presence of antibodies against SARS-CoV-2 is commonly checked by serological tests. The detection of specific antibodies indicates a past infection with a pathogen even if this infection has been asymptomatic. Depending on the concentration of those antibodies their presence can indicate a resistance against future infections with the same or highly similar pathogens. Immunoassays are also important because they are considered easier to upscale as they can generally be produced at a lower cost than PCR assays1. These immunoassays work with sera aliquots as sample material. Those aliquots are screened for the presence of antibodies by enzyme-linked immunosorbent assay (ELISA).

The methods and equipment shown are intended for molecular research applications. They are not intended, verified, or validated for use in the diagnosis of a disease or other human health conditions.

Collect Plasma, Serum

Primary samples are usually whole-blood samples. In most cases, plasma (liquid blood components without any cells) or serum (plasma without fibrinogens) is harvested by centrifugation. These samples are then transferred to plates or tubes.

Centrifugation

  • Key for dividing solid from liquid blood components
  • A wide variety of centrifuges and adapters allow you to handle blood samples in different quantities and vessels

 More about Centrifugation


Manual Liquid Handling

  • Mechanical or Electronic Single Channel Pipettes are ideal for precise collecting of supernatant (plasma, serum) without disturbing the pellet
  • Filter Tips assure the sample integrity of primary samples

More about Manual Liquid Handling


Plates and Tubes

  • Leachable free plates and tubes for optimal processing and storage of samples

More about Laboratory Consumables


Storage and Management

  • Serum or plasma can be stored in high-quality Cryo tubes
  • An Ultra-Low Temperature Freezer allows long term storage of whole blood, plasma or serum
  • The eLabJournal® and eLABInventory allow for effortless archiving and documentation

Eppendorf CryoCube F570 ULT freezer for storage of lab samplesMore about Sample staorage solutions

Aliquot Samples

To process the collected samples, samples need to be transferred to tubes or plates.

Manual Liquid Handling

  • Mechanical or Electronic Single Channel Pipettes are ideal for precise reformatting of samples from primary vessels
  • Filter Tips assure the sample integrity of primary samples

More about Manual Liquid Handling


Automated Liquid Handling

  • Benchtop Pipetting Robots support you to deal with an increased sample throughput
  • 96-channel head step automation is a very efficient tool to copy plates quickly

More about Automation Solutions


Plates and Tubes

  • Leachable free plates and tubes for optimal processing and storage of aliquoted samples

More about Laboratory Consumables

ELISA

Setting up the ELISA involves adding the samples to the epitope or antibody-coated plates and then adding antibodies/secondary antibodies. The concentration of antibodies in the sample can then be measured by detecting a colorimetric or fluorescent marker. The whole process involves several washing and drying steps.

Manual Liquid Handling

  • Single Channel Pipettes are ideal for adding samples from tubes
  • Multichannel pipettes can save time when processing ELISA plates and adding and removing reagents and washing buffer
  • A Dispenser and Combitips® help add reagents in a quick and precise way. They also help minimize handling steps, used materials and reduce the risk of cross-contamination.

More about Manual Liquid Handling


Automated Liquid Handling

  • Benchtop Pipetting Robots and 96-channel head pipettors allow efficient addition of buffers for washing steps

More about Automation Solutions


Tempering and Mixing

  • ThermoMixers are especially helpful for mixing reagents and samples in a plate format

More about Temperature Control and Mixing

Analysis

This step describes the actual photometric ELISA measurements. After the measurements, the samples can be stored for further testing.

Storage and Management

  • Plates and tubes can be stored using Ultra-Low Temperature Freezer
  • The eLabJournal® and eLABInventory allow for effortless archiving and documentation

Eppendorf CryoCube F570 ULT freezer for storage of lab samplesMore about Sample storage solutions

1 Serological tests for COVID19 are important to upscale analysis of COVID19, as they can generally be produced at a lower costs than PCR assays, and may promise to allow the screening for immunocompetent people. These assays, do require the handling of sera, testing of aliquotes.