Enzyme-linked immunosorbent assay Term Paper Example | Topics and Well Written Essays - 2000 words

Enzyme-linked immunosorbent assay - Term Paper Example Most of the time, this waste is hazardous and may cause detrimental effect to any living organisms, including human (Freedman, 3-9). One of the most common environmental toxicant includes the polychlorinated biphenyls or PCBs. PCBs are man-made organic chemicals belonging to a broad family of hydrocarbons. It was used in many industrial and commercial applications because of its good chemical properties like being non-flammable, high boiling point, chemical stability and good electrical insulating properties. These compounds are widely used for many applicants such as transportation and coolants. PCBs are also used as plasticizers in paints, plastics, and rubber products. It was first manufacture during 1929 but their use had been banned in 1979 upon determining its dangerous effects to both the environment and human health (Davis and Wade, 2-6). PCBs have a range of toxicity and vary in consistency from thin, light-colored liquids to yellow or black waxy solids. These toxic compound s are considered to be persistent organic pollutant for it do not degrade easily and may remain for a long time in the environment. PCBs can contaminate some parts of plants and food crops. PCBs may also be taken up into the bodies of small organisms in that lake including fishes. These toxic compounds may bioaccumulate in these food sources and ingestion may have many adverse health effects in human with symptoms such as skin condition or changes in the blood which may lead to liver damage. Some food which contains PCBs can cause poisoning to the consumers. Moreover, some studies report the health effect of PCBs in children of mothers who were exposed to PCBs (ATSDR, 285-290). Hence, it is important to detect this compound in the environment to prevent its hazardous effect. One of these methods of detection includes the use of Enzyme-Linked Immunosorbent Assay or ELISA Analytical Technique Enzyme-linked immunosorbent assay (ELISA) is a biochemical technique which allows rapid scree ning and quantification of an antigen in a sample. It is used mainly to detect the presence of an antibody or an antigen in a sample. The ELISA has been used as a diagnostic tool in medicine and as detection or measuring tool of environmental toxicants. In ELISA, an antigen is affixed to a surface and a specific antibody is applied over the surface so that it can bind to the antigen. This antibody is linked to an enzyme, and in the final step a substance is added that the enzyme can convert to some detectable signal, which is most commonly a color change in a chemical substrate (Lequin, 2415-2416). Enzyme-linked immunosorbent assay or (ELISA) analysis biochemical technique is used to measurement of organic contaminants such as polychlorinated biphenyls in an environmental sample. Performing an ELISA includes at least one or more antibody with specificity for an antigen. The sample, which has unknown amount of antigen, is immobilized on a solid support either non-specifically or spec ifically. The immobilization process occurs in two ways. One process is by the adsorption to the surface wherein a sample containing an antigen is adsorbed into an inert surface, usually a 96-well polystyrene well. Another process involves capturing another antibody specific to the same antigen, as in a "sandwich" ELISA (Lequin, 2417). The detection antibody is added after the antigen is immobilized, forming a complex with the antibody. This is usually done by washing the surface with a solution of a non-specific protein to block proteins

INTERCULTURAL Essay Example | Topics and Well Written Essays - 500 words

INTERCULTURAL - Essay Example on the positive altitude of her friends and parents, where they did not allow the intimidation of the civil rights movement to inflict fear on their children, rice was trained to remain positive in every aspect of live (The right scoop, 2010). During her interview with Kate Couric, Rice sounds positive concerning their hard task of facing their two enemies that threatened their national security. She accepts the fact that both Iraq and North Korea were dangerous in their own way but she assured her that they were going to deal with both of them separately (Schneider, 2010). The parents to Condoleezza tried their best to protect their little gal from the areas that would bring her face to face with discrimination, but though she was young, she was so much responsive to the civil rights struggle and the concerns that pertained to Birmingham. She is also seen to be actively involved in settling the disputes that existed between U.S and North Korea together with Iran. As witnessed in her childhood experiences, it is clear that Rice was an intelligent child, where her intelligence is also exhibited in the manner she handles the insecurity concerns brought about by North Korea and Iran. She believes in negotiations between rivalry communities, and dialogue with your own enemies (Schneider, 2010). After being asked by Kate on whether her government has ever taken the initiative to conduct negotiations with their enemies, she says that, they have made an effort to engage North Korea in the framework of six party talks. Having grew in a terrorism atmosphere, Rice in her interview with Kate is seen to revolve around the aspect of maintaining peace with his rivalry communities, where she is even going to the extent of involving the neighbouring communities to assist the US in convincing the North Korea and Iran to abandon their intentions of embarking on using weapons of mass destruction (The right scoop, 2010). Having seen what rivalry could bring during her early days of