The extensive use of lead and its compounds in industrial production has resulted in severe lead contamination which is listed as one of the most concerning environmental problems. Owing to its broad presence and particular toxicity, human beings are vulnerably exposed to lead-contaminated water, food, soil, and dust. Consequently, in addition to the immune system malfunction, other troubles including hypertension, cardiovascular, kidney, and nervous diseases may occur in human body.

However, lead contamination is just a tip of the iceberg. Cadmium, mercury, chromium, and other heavy metal contamination continuously pose a threat to both human and animal health. To address the pressing issues, scientists put forward the solution of hapten design and synthesis, unlocking the door for efficient heavy metal detection.

Heavy metals are unable to obtain antibodies for they are not immunogens in nature and fail to trigger immune responses, whereas they could be incorporated into chelators covalently to serve as metal-chelate complexes which are classified as haptens. If further conjugated to carrier proteins, these haptens can turn into immunogenic, with evidence showing that antibodies would recognize them and have specificity for them as well.

Heavy metal hapten design and synthesis are considered the starting points among the overall procedures of producing antibodies to detect metal ions. In general, superior hapten design and synthesis refer to three key elements including chelators, carrier proteins, and the structure of the immobilized metal-chelate complexes, inspiring scientists to concentrate on changing them to increase the specificity and sensitivity of immunoassays. For instance, during the hapten design and synthesis for lead, technicians would in the first place select the most effective chelators that display a high affinity for lead, such as EDTA, DTPA, and CHXDTPA. Then the lead-chelate complexes are supposed to be covalently connected to suitable carrier proteins like KLH, BSA, and OVA. Eventually, complete immunogens are available for the preparation of antibodies that can detect lead or lead-chelate complexes at levels below the threshold.

Nowadays, the surging heavy metal pollution urges everyone concerned to shoulder their responsibilities, notably the industries regarding pharmaceuticals and biotechnologies. Several biotech companies, in effect, have made some contributions to this field. For example, Creative Biolabs, the undisputed global leader skilled in hapten design and synthesis, has served quantities of demanding projects about heavy metal monitoring. Hopefully, with the joint efforts of all, heavy metal problems will be mitigated or nearly eliminated tomorrow.