Quantifying Serum Antiplague Antibody with a Fiber-Optic Biosensor

Abstract

The fiber-optic biosensor, originally developed to detect hazardous biological agents such as protein toxins or bacterial cells, has been utilized to quantify the concentration of serum antiplague antibodies. This biosensor has been used to detect and quantify the plague fraction 1 antigen in serum, plasma, and whole-blood samples, but its ability to quantify serum antibodies has not been demonstrated. By using a competitive assay, the concentration of serum antiplague antibodies was ascertained in the range of 2 to 15 μg/ml. By making simple dilutions, concentrations for 11 serum samples whose antiplague antibody concentrations were unknown were determined and were found to be in good agreement with enzyme-linked immunosorbent assay results. The competitive assay method could be used to effectively determine the exposure to plague of animals or humans or could be applied to other diseases, such as hepatitis or AIDS, where the presence of antibodies is used to diagnose infection.

Sensing of proteins in human serum using conjugates of nanoparticles and green fluorescent protein

“…Proteins present in small quantities are specifically detected by monoclonal antibodies. With this method each monoclonal antibody has to be developed and can detect only one specific protein 6 , 7 , and technical difficulties in regard to quantification are significant 8 . Alternatively, electrophoresis is the current tool of choice in clinics for overall serum analysis, despite the relative insensitivity, lack of resolution, and difficulty in quantification of this method 9 .…”

Biosensors: Current State and Prospects of Applying in Laboratory Diagnostics of Particularly Dangerous Infectious Diseases

“…Иммобилизация антител внутри волокна позволяет осуществлять специфическую индикацию. На основе оптоволокна были разработаны иммуносенсоры для выявления капсульного антигена «фракция 1» чумного микроба [10,11,14] и антител к нему [12], для обнаружения протективного антигена сибиреязвенного микроба [13]. Чувствительность биосенсоров составила 5-50 нг/мл белка [10], время отклика -1 мин [14].…”

Yersinia pestis detection by loop-mediated isothermal amplification combined with magnetic bead capture of DNA

“…Y. pestis was often detected by bacterial isolation and microscopy observation, 9 phage lysis assay, 10 , 11 ELISA assays based on the detection of F1 antigen and antibodies against Y. pestis , 12 , 13 , 14 , 15 conventional PCR assays, 16 , 17 , 18 real-time quantitative PCR assays, 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 biosensors based on fiber-optic or upconverting phosphor technology, 29 , 30 , 31 solid-phase radioimmunoassay based on radiolabeled monoclonal antibody for the detection of plague antigen. 32 All these methods are playing an important role in the diagnosis of plague, but these methods either are time-consuming and laborious, or require expensive equipment and personnel with a high level of technical expertise.…”