Since the discovery and widespread application of monoclonal antibodies in the latter half of the 20th Century, the analytical methods used within the field of immunochemistry have become increasingly granular. There are now numerous methodologies available for the detection of drugs and antigenic material in organic samples, including immunosorbent assays and immunoblotting.
This article will explore the three primary immunochemistry analysis methods in more detail:
ELISA or EIA Immunochemistry Analysis
Enzyme-linked immunosorbent assays (EIAs or ELISAs) are among the most broadly-used immunochemistry methodologies for detecting small analytes such as drugs of abuse in organic samples using colorimetric recognition systems. Target antibodies bind to specific molecules in a sample and register chromatic responses relative to the presence and concentration of that given antigen.
There are three distinct EIA techniques for detecting analytes within organic samples: competitive EIAs; sandwich assays; and direct EIAs. We explored these immunochemistry analysis methods in greater detail in a previous blog post.
An immunochromatographic assay, or lateral flow test, is used for preliminary detection of pre-defined analytes within a biological liquid sample. Liquid molecules are absorbed by an immunosorbent capillary and transferred to a sample bed containing the detection reagent. The sample and the conjugate mixture transfer to a final capillary bed where antibody-specific binding occurs and registers a colorimetric response that is directly proportional to the presence and concentration of the target antigen.
Lateral flow tests are commercially available immunochemistry assays that are routinely used for preliminary drug screening, testing for pregnancy, infectious diseases, and food contamination to name a few.
Western blotting, or immunoblotting, is an electrophoretic method of detecting specific proteins within a biological analyte. Denatured proteins are blotted onto a membrane, which is then blocked to prevent nonspecific antibody binding. Application-specific antibodies are then used to probe the sample and encourage detectable bonding with appropriate substrate chemicals. Various methods use fluorophores or chemiluminescent enzymes to produce the chromatic response necessary to observe antigen-antibody binding within a sample.
This qualitative biochemical method is used in a range of immunochemistry applications.
Immunochemistry with Pyxis Laboratories
Pyxis Laboratories provides a unique immunochemistry reagent service, with demonstrable experience in the preparation and synthesis of high-purity drug conjugations for all established immunochemistry diagnostic testing techniques. Our lot-to-lot reproducibility is unparalleled, with a range of made-to-order conjugations for research applications, including:
- Alcohol such as, ethyl glucuronide-BSA (EtG-BSA);
- Amphetamines such as, Amphetamine-BSA, Methamphetamine-BSA, methcathinone-BSA, MDMA-BSA, MDPV-BSA, Mephedrone-BSA and Methylphenidate-BSA (Ritalin-BSA);
- Benzodiazepines, such as Oxazepam-BSA and Clonazepam-BSA;
- Cannabinoids such us, delta-8-THC-BSA, delta-9-THC-BSA; and synthetic cannabinoids such as, JWH-018-BSA, ABpinaca-BSA, UR144-BSA;
- Cocaine, such as BZEG-BSA;
- Hallucinogens/Anesthetics such as, Ketamine-BSA and PCP-BSA;
- Nicotinic such as, Cotinine-BSA.
- Opioids such as, Buprenorphine-BSA, Fentanyl-BSA, Methadone-BSA, Morphine-BSA, Oxycodone-BSA, Propoxyphene-BSA and others such as Chloramphenicol-BSA, Gabapentin-BSA and N-acetyl glucosamine-BSA (NAG-BSA).