Aug 5 2010
Fujitsu and Nagoya University have developed a novel technology that helps in quick identification of venomous proteins which cause food toxicity.
A new sensor that can capture the proteins which are lethal in nature has been devised blending the use of synthetic antibodies (DNA aptamers) which is capable of capturing toxic proteins with a signal converter, which converts the outcome of toxic signals to optic signals. This unique sensor provides protein detection up to 100 fold quicker and stronger than the other currently employed methods. This sensor arbitrated approach can be utilized to ensure food safety.
Different types of proteins play a major role in the nurturing and revamping of body tissues and carry out extensive array of functions in movement, genetics, digestion and immunity, provides source of energy and is absolutely crucial for overall good health. Certain potent proteins such as botulinum toxins staphylococcus aureus and scorpion venoms are toxic to humans. Sterilization of food by heat kills harmful bacteria which thrive in it, whereas the toxins produced by the bacteria are heat resistant and can poison the food. By tracking down such poisonous protein toxins, food poisoning can be impeded.
Antibodies are proteins that detect antigenic toxins, and are found in blood or other fluids in the body and aid in identifying certain foreign proteins (antigens), there by providing immunity. Existing antibody mediated toxin detection method is quite expensive, time consuming and fails to meet the quality since it can be synthesized only on immune system in mammals, whereas, synthetic antibodies retain the antigen specificity, as conventional antibodies do not require a mammalian system and can be easily synthesized invitro.
This technology encompasses several features. At the outset, they synthesized antibodies with high affinity towards toxic proteins, using DNA and produced large quantities of these antibodies by random connection, yielding 1014 types of artificial antibodies. From this array they could choose toxic protein specific antibody and all these are subjected to various biochemical assays.
Second step was towards converting the signals. In this method synthetic antibodies having high kinship towards toxic proteins have been attached to the end of a fluorescent dye coated DNA-based signal converter. Upon binding of proteins with the antibody, the dye fluoresces and by noting the modulations in the dye’s luminence, the existence and quantity of toxins can be recorded exactly.
Third step was to develop a mechanism, to improve the sensor’s ability to identify toxins effectively. To achieve this objective, the fluid sample is allowed to flow onto the surface of the sensor, thereby enabling the synthetic antibodies coated on the sensor to identify and capture 90% of toxins in the fluid sample.
The results of this study clearly indicate the high-speed toxin detection ability of this technology which can be implied for quality checking in food industry providing safety.
Fujitsu University also plans to improve the antibodies affinity, and make it cost effective so that conventional antibody testing for diseases and food can be replaced by this artificial antibody technology.
Source: http://www.nagoya-u.ac.jp