Highly Sensitive Fluorescent Immunoassay of Human Immunoglobulin G Based on PbS Nanoparticles and DNAzyme

DNAzyme-Mediated Assays for Amplified Detection of Nucleic Acids and Proteins

“…Strategies that convert the detection of other types of targets (e.g., nucleic acids and proteins) into the detection of metal ions can expand the applicability of these DNAzyme sensors to beyond that of metal ions. − One strategy is to use metallic nanoparticles as a signal tag, as this offers two main benefits: (1) the detection of the target can be further amplified by releasing thousands of metal ions from a single metallic nanoparticle and (2) the use of metallic nanoparticles facilitates the labeling of affinity ligands with metal ions.…”

“…The authors achieved a detection limit 220-fold lower than that of conventional enzyme-linked immunosorbent assay (ELISA). A similar strategy was used to detect human immunoglobulin G (IgG), in which Pb 2+ released from PbS nanoparticles was detected by a fluorescent DNAzyme sensor . It is conceivable that other metallic nanoparticles can be used for signal tags and that DNAzyme sensors with different signal readouts can detect these released metal ions.…”

Sensitive detection of protein biomarkers using silver nanoparticles enhanced immunofluorescence assay

“…Therefore, the sensitivity of immunofluorescence assay is limited due to the limited photostability of fluorescent labels and recognition abilities of antibodies 15, 16. Several different strategies have been explored to solve the above problems, including the development of new fluorescent materials, the improvement of fluorescence detection instrument, the establishment of integrated analysis system 17-21. Among these strategies, the application of functionalized nanomaterials has provided a new opportunity for the practical application of fluorescence techniques in biomarkers detection.…”