RHA™ anti-Pb2+ monoclonal antibody, clone Pb

Lead ion (Pb²⁺) is one of the most common heavy metal pollutants. Studies have found that Pb²⁺ is highly toxic to the human gastrointestinal tract, kidneys, cardiovascular and central nervous systems, and can cause serious diseases such as hypertension, hepatitis, peripheral neuritis, etc. According to statistics, 1 million people die from lead poisoning every year, and millions of people are exposed to low-level lead environments. Among them, clinically found that about 30% of idiopathic intellectual disability, 4.6% of cardiovascular diseases and 3% of chronic kidney diseases are caused by exposure to lead environments. Studies have shown that the sources of lead exposure mainly include electronic waste and lead-acid battery recycling, environmental pollution caused by mining and smelting of lead ores, food containers coated with lead-containing ceramic glaze, lead pipes and other lead-containing water supply accessories, lead paint, etc. Therefore, a fast, convenient, highly sensitive and low-cost Pb²⁺ detection method is needed. At present, the methods commonly used to detect Pb²⁺ include: atomic absorption spectroscopy (AAS), inductively coupled plasma-atomic emission spectroscopy (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS), atomic fluorescence spectroscopy (AFS), X-ray fluorescence spectroscopy, spectrophotometry, colorimetry, and electroanalytical chemistry. These detection methods have accurate results, but they are expensive, time-consuming, complex sample pretreatment, complex equipment operation, and high technical requirements, which have created obstacles for Pb²⁺ detection. Different from the traditional detection method is the biochemical analysis of Pb²⁺. The biochemical analysis of Pb²⁺ refers to a method that can reversely infer the reaction substances through chemical reactions and obtain specific conclusions by detecting the reactants. It has the characteristics of rapid development, high efficiency, sensitivity, and low cost. Among them, the immunological analysis method has attracted much attention.

Figure 1. Diagrammatic representation of lead accumulation in the major organs.(Source: M Samuel Collin, et al. 2022)

Immunological analysis is a method of using known antigens (antibodies) to detect unknown antibodies (antigens) based on the specific binding of antigens and antibodies. Since heavy metal ions are non-immunogenic, when immunoassay is applied to heavy metal ion detection, it is necessary to first combine them with suitable metal complexes to make them antigenic, and then connect this complex to the carrier protein. After immunogenicity is produced, the heavy metal content is measured. The methods commonly used to detect Pb²⁺ are mainly: enzyme-linked immunosorbent assay (ELISA) and colloidal gold immunochromatography (GICA). This method has the advantages of high specificity, high sensitivity, low cost, and short detection time, and can overcome the limitations of methods such as AAS and ICP-AES. The ELISA method is an immunological detection method based on antigen-antibody reaction. Some researchers have prepared monoclonal antibodies against Pb²⁺ and used indirect competitive methods for detection. The minimum detection limit is 0.01 μg/mL. The recovery rate of this method is extremely high and has certain development value. Others have prepared monoclonal antibodies based on artificial antigens of cadmium ions, established heterologous indirect competitive ELISA detection methods for cadmium chelates, and used nanosilica as an adsorbent to pre-enrich cadmium in simulated samples, combined with heterologous icELISA methods for quantitative analysis, providing technical support for on-site rapid detection of heavy metal cadmium. GICA is a detection method that uses colloidal gold to react with the object to be detected and antibodies. It can be used for indirect qualitative or semi-quantitative detection and is a visual reaction. Fluorescence immunoassay (FIA) is a detection technology based on antigen-antibody specific reactions. The signal indication of this method is fluorescence, and there are mainly fluorescence polarization immunoassay (FPIA) and fluorescence quenching immunoassay. Among them, the FPIA method mainly uses fluorescently labeled metal chelates to compete with monoclonal antibodies with the sample to be tested, uses special instruments, and compares the standard curve to obtain the heavy metal concentration in the sample.

Lead ions
Plumbum
Pb