Electrochemical biosensor using SnO2 colloidal quantum wire for monitoring the interaction of microcystin antigen-antibody.

Electrochemical sensors that incorporate immunoassay principles have the ability to monitor dynamic processes of antigen-antibody interactions in real time. In this study, a gold electrode was modified with tin dioxide colloidal quantum wire (SnO2 QWs) and then coated with the leucine/arginine subtype microcystin (MC-LR) antibody. The active site of SnO2 QWs that was not bound by MC-LR antibody was then passivated with bovine serum protein (BSA). When the MC-LR antigen binds specifically to the antibodies on the electrode's surface, it triggers electrochemical reactions and generates electrical signals at specific voltage conditions. The SnO2 QW exhibits excellent electron transport ability, and its ability to form a loose and porous microstructure on the gold electrode surface, which is conducive to the receptor function of the biosensor. The results show a high affinity between the MC-LR antigen and antibody, ranging from 1 pg/mL to 10 ng/mL of MC-LR antigen concentration. The kinetic characteristics of the immune reaction between MC-LR antigen and antibody were elucidated, obtaining a binding constant of 1.399 × 1011 M-1 and a dissociation constant of 7.147 pM, demonstrating the potential of electrochemical biosensing technology in biomolecular interactions.

Research progress of leprosy and its control status in Hainan Province / 中国热带医学

@#Abstract: Leprosy, as an important neglected tropical disease (NTDs), has a tremendous impact on the patients’body and psychology, families and society. In this paper, we reviewed the progress of epidemiology, genetic factors, immune mechanisms, diagnosis and treatment of leprosy, and introduced the changes of national prevention and control policies and the prevention and control process of Hainan Province, so as to improve the clinical understanding among healthcare professionals. According to the World Health Organization's (WHO) global annual leprosy situation report data, the number of new cases and the incidence rate of leprosy have been showing a downward trend worldwide. In China, the epidemic situation of leprosy remains in an overall low-endemic state. However, the long-standing low-endemic status of leprosy and its wide and uneven distribution pose challenges to the prevention and control of leprosy. The pathogenesis of leprosy is mainly related to skin barrier, immune deficiency, and related signaling pathways. Serological testing, cytokines, and microRNA markers can all be used to assist in the early diagnosis of leprosy, while also helping to distinguish different types of leprosy, predict leprosy reactions, evaluate efficacy, and monitor family contacts. The main treatment plan for leprosy involves combination chemotherapy with drugs recommended by the WHO, such as rifampicin, dapsone, clofazimine and other drugs. Currently, the main prevention and treatment strategies for leprosy are early detection, early diagnosis and early treatment, controlling the source of infection, protecting the healthy population, preventing the occurrence of deformity, and improving the quality of life after recovery. At present, Hainan Province as well as the whole country is in a low-epidemic state, but healthcare professionals still need to improve their awareness of prevention, reduce their incidence rate, and strive to achieve the goal of "zero leprosy" as soon as possible.