BioSupply offers a broad range of fully validated and ready to use ELISA kits. These immunoassays are optimised to provide high specificity and sensitivity over a dynamic range with no cross-reactivity and are reasonably priced that is comparable to other leading manufacturers. All of our kits are guaranteed to work in the target molecule, sample type, species and applications as listed on our website and in the datasheet.
ELISA is short for “enzyme-linked immunosorbent assay” is a technique that is performed by various scientists for professional use within a research laboratory. This research can be either relating to medical or clinical diagnostic procedures.
Immunoassay methods are a fundamental tool for medical screening and evaluating a large array of biological markers which are released by the human body in response to the exposure to various target molecules. The ELISA protocol provides a versatile technique in order to detect proteins, antibodies, hormones and peptide molecules that are present within various different types of samples.
Before ELISA kits were created, there were limited options for conducting an immunoassay. Over the years, immunological based assays have become the benchmark for the quantification of antigens and now there are various methods and techniques that can be applied when they are being used during testing.
BASIC ELISA KIT PRINCIPLE
Antigens are immobilised in ELISA assays. The way this is done is either directly or indirectly through the use of a capture antibody that is immobilised on the surface of a microtiter plate. The antigen is then placed with a detection antibody conjugated with a molecule that is amendable for detection, this could be an enzyme or a fluorophore. Immunoassay methods are based on the principle of the antibody detecting a target antigen through antibody-antigen interactions that are highly sensitive and specific. A negative result is produced when the antibody and antigen do not react with each other.
ADVANTAGES OF IMMUNOASSAYS
Immunoassay kits offer many significant advantages when compared to other diagnostic methods. Some of the benefits of using the ELISA kit protocol include the following:
- Simple to use
- Highly sensitive
- High throughput
- Provide measurements
- Quality testing tools
- Easy to automate
- No requirement of radioactive substances
- Accurate when it comes to medical diagnosis
- Able to produce quick results
- Cheap in price and accessible
The use of ELISA method in diagnostic research means that various antibodies, hormones and biological markers can be detected. The targets can be analysed and many different samples and combination of species can also be tested. ELISA kits usability means they are user-friendly and suitable for individual scientific or clinical laboratory use. Immunoassays are also frequently used in human or animal testing.
ELISA KITS – CLINICAL USE
Medical professionals are able to use ELISA kits in research and laboratories when compared with other diagnostic tests. So what is an ELISA test? Essentially, an ELISA kit will use components of the immune system, for example IgM, IgG or IgA antibodies. Immunological based assays also use chemicals to detect the body’s immune responses to things such as infectious microbes. There are many established applications of ELISA being using in clinical medicine and medical science, for example in diagnostic protocols measuring human Alzheimer, dementia, neurological disorders, bone metabolism, nephrology, endocrinology diagnostics, cancer studies, embryogenesis, diabetes, wound healing, infectious disease research, autoimmunity, to name but a few.
There are many commercial business suppliers selling a variety of ELISA kits within the United Kingdom and globally. As the interest in science and research continues to gather momentum, particularly during a global pandemic, so too does the interest in immunoassay kits and their ability to extract important and sensitive information related to health and wellbeing.
WHAT ARE ELISA ASSAYS USED TO DETECT?
ELISA kits are used to detect and diagnose the following:
- Endocrinology (Thyroid Function, Nephrology, Diabetes, Bone and Mineral Metabolism, Fertility)
- Immunology and Cytokines (Apoptosis, Matrix Metalloproteinase, Cell Adhesion Molecules, Chemokines, Interleukins)
- Tumor Markers
- Infectious Diseases (Bacterial, Fungal, Viral, Parasites)
- Cardiac Markers
- Food Intolerance and Safety
- Biogenic Amines
- Veterinary Diagnostics
Immunoassays are also diagnostically useful as experimental investigations such as those done to detect and identify compounds from a range of organisms (human, mouse, rat, dog, rabbit, horse, bovine, porcine and monkey). ELISA kits were the first screening test used to detect HIV due to the high sensitivity they offer.
ELISA assays are a great screening tool and are often used before further undertake in-depth scientific testing takes place.
HOW ARE ELISA TESTS PERFORMED?
As a diagnostic tool, ELISA kits have many benefits as mentioned above. However, it is essential that if they are to continue to be a screening tool that the technique used when the kit is used is performed with accuracy and precision. If the assays are not used in accordance with the instructions they come with, then this can affect the reliability of the results and the success of the ELISA kit as a scientific diagnostic tool.
ELISA kits as a testing tool are straightforward when it comes to using them. To use an ELISA test you need to have a sample (usually blood, urine or saliva). The sample is sent to a clinical laboratory for testing and analysis. In the laboratory, a lab technician will place the sample in a microtiter plate that will also contain the specific antigen that relates to the condition being tested for. If the sample does have antibodies to the antigen then the antibody and the antigen will bind together. The laboratory technician will do further checks and tests by adding a specific enzyme to the microtiter plate and analyse and observe how the antigen and the sample react.
One of the main advantages of using ELISA kits is that it makes it possible to test and screen various sample types including the following:
- Cellular extracts
- Tissue extracts
- Cell culture
- Various other biological fluids
WHAT IS CELL BASED ELISA KIT?
A cell based ELISA kit, also known as In Cell ELISA is a immunocytochemistry method or technique. Cell based ELISA kits are used to quantify target post translation modification or proteins in cultured cells.
Cell based ELISA assays are deemed to be a great testing tool as they are lysate free, convenient, dynamic, and sensitive assays. They measure the amount of protein phosphorylation contained in cells.
CHOOSING THE CORRECT ELISA KITS
It is important that the correct ELISA kit is chosen before you begin your diagnostic testing. There are 4 main types of ELISA:
- Indirect ELISA
- Direct ELISA
- Competitive ELISA
- Sandwich ELISA
Each ELISA procedure has a distinct quality and suitability depending on the type of testing you are doing.
- Indirect ELISA is a specific technique that requires a two step process for detection.
- When using a direct ELISA, the antigen is immobilised on the surface and detected using a antibody that is specifically for the antigen.
- Competitive ELISAs are also known as competitive immunoassays or inhibition ELISAs. They measure the concentration of a particular antigen by checking signal interference.
- Sandwich ELISAs, or sandwich immunoassays, are probably the most commonly utilised format. The technique requires two antibodies usually known as matched antibody pairs.
Some popular enzymatic markers that are used in ELISA assays include:
- OPD: also known as o-phenylenediamine dihydrochlorine
- TMB: tetramethylbenzidine
- ABTS: Azinobis
- PNPP: nitrophenyl Phosphate disodium salt
ELISA kits are not only useful as a tool for medical testing. They are also used by private businesses to test within the food industry. Immunoassays have been used to detect allergen including milk, nuts, and eggs, and are often used to test for coeliac disease. As far as screening and testing goes, the engineering of the ELISA test has led to significant progress in medicine and other industries requiring testing.