The challenge:

Identification of novel clinical markers, stricter environmental legislation, growing consumer concern regarding food safety and focus on disease self-management, are just a few of the factors leading to the requirement for an array of sensitive and specific assays that are inexpensive, easy to use and portable. The technology developed by the BBG has answered these mature market needs with the development of a generic quantitative immunostrip technology, that may act as a platform for adaptation of any laboratory based immunoasssay to a quantitative rapid test format. BBG has developed immunostrips based on both diffusional and non-diffusional transduction, capable of ng/L (ppt) detection limits. Typical response times are 15-20 minutes and sample volumes can be as low as a few hundred nanolitres. Typical immunostrip membranes are employed and the electrodes are produced by thick film technology, thus allowing a low cost production. The immunostrip format can be modified for dual and multiple analyte detection.

The group has developed immunostrips for both competition and sandwich immunoassays. Competition assays are generally employed for small molecules and sandwich for larger molecules. The team has also established the biocompatibility of the immunostrip formats with various solvents and possible sample matrices.

The applications:

The scope of application of the developed technology is enormous. In recent years, advances in the production of monoclonal antibodies has facilitated detection of practically any desired analyte, from heavy metals to drugs, and clinical markers to food pathogens using immunoassay.

The potential market for disposable, tests capable of rapid, low cost, quantitative immunoassay is a billion dollar market with applications in the sectors of clinical diagnostics, food quality, police control, veterinary diagnostics, military security and environmental monitoring, to name a few.

The team at BBG offers the development of an individually tailored package, comprising reading device, sample procurement and, if required, pre-treatment device and disposable immunostrips. monitoring.

BBG possesses proprietary knowledge in the area of molecular wiring, which employs redox polymers with non-diffusional mediators that can transfer electrons from the redox centres of the enzyme label (HRP/GOX) to the electrode. Additionally, the group has developed novel substrates for ALP labels as well as the use of novel tailor designed genetically modified enzymes as labels, thus achieving very high sensitivity (GOX = Glucose oxidase; ALP = Alkaline phosphatase; HRP= Horse radish peroxidase).

BBG has developed immunostrips based on both diffusional and non-diffusional transduction, capable of ng/L (ppt) detection limits. Typical response times are 15-20 minutes and sample volumes can be as low as a few hundred nanolitres. Typical immunostrip membranes are employed and the electrodes are produced by thick film technology, thus allowing a low cost production. The immunostrip format can be modified for dual and multiple analyte detection.

The group has developed immunostrips for both competition and sandwich immunoassays. Competition assays are generally employed for small molecules and sandwich for larger molecules.The team has also established the biocompatibility of the immunostrip formats with various solvents and possible sample matrices.

The group has developed reading, sample procurement and sample extraction devices for use with these immunostrips and additionally the technology can be adjusted for use in microsystems requiring nL sample volumes.