Research On Piezoelectric Biosensors For The Detection Of DNA Encoding Staphylococcal Enterotoxin B

The 21th Century is the critical development period of life-sciences. The detection control and the analysis of samples in bio-techniques ultimately depend on the information from biosensor technique. Considering the sensitivity of piezoelectric quartz oscillator to quality, the piezoelectric biosensors (PEBS) that are based on the changes of oscillator's parameters due to the surface absorption associated with contaminants, have been developed. Nowadays, PEBS has become a significant research field since the technique shows the advantages of stable capability, simplicity in instrument construction and operation, and no label to be needed.Staphylococcus aureus (S. aureus) is a major cause of bacterial food poisoning. Staphylococcal food poisoning is resulted from the ingestion of enterotoxins preformed infood by certain strains of S. aureus. Staphylococcal enterotoxins (SES) are categorized to a family of seven major serological types of emetic enterotoxins with heat stability. Because of its incredible toxicity and stability, Staphylococcal enterotoxin B (SEB) is considered as a potential threat as a biological weapon of mass destruction. Therefore, the determination of SEB is very important for food hygienic analysis as well as for clinical analysis. Nucleic acid hybridization technique is one of the widely-used methods in molecular biology and gene technology. The present work has developed piezoelectric biosensors used in the detection of SEB DNA by tacking the piezoelectric quarts crystal as a sensitive component while synthetic oligonucleotide probe as recognize molecule. The paper mainly introduces the development of PEBS and SES detection, and focus on the principle, constitutes and detection results of SEB DNA by using the quartz crystal microbalance (QCM) and surface acoustic waves (SAW)piezoelectric biosensors respectively. In addition, the Chemilurm'nescence (CL) behavior at asystem of Ce(IV)-rhodamine B in sulfuric acid has also been discussed in Part Two of thepaper.Part one The studies of piezoelectric biosensors and detection of StaphylococcalenterotoxinsChapter one The progresses in piezoelectric biosensors and detection ofStaphylococcal enterotoxinsSection One The progresses in piezoelectric biosensorsIn this section, a review is reported with 69 references about the piezoelectric biosensors, including the principle and constitutes of PEBS, the classification of PEBS, surface modification technique in PEBS and the application of PEBS in immunoassay, detection of the gene and microorganism, coupling with other techniques, moreover, the development of PEBS was involved.Section Two The progresses in detections of Staphylococcus aureus and staphylococcal enterotoxinsIn this section, the author introduced classification, typology and toxicological study of Staphylococcus aureus in addition to relevant determination methods including PCR technique, nucleic acid hybridization technique, biosensor technique, superantigen technique. Chapter Two Detecting the gene of staphylococcal enterotoxin B using a surface acoustic wave biosensorA kind of SAW biosensor for detecting the gene of staphylococcal enterotoxin B was developed. The Love wave device with the substrate of ST-cut quartz and the guiding layer of Si02 was used as the SAW biosensor. DNA sensor employing synthetic SEB DNA probe as a molecular recognizing component was utilized to detect SEB by measuring SEB DNA in samples. It demonstrated that biosensor used for measurement of SEB DNA, had a possible usage not only for the simple SEB DNA samples but also for the complex samples in the presence of extra enterotoxins' DNA that could not evoke a positive response. The assay sensitivity was 75ng/ml and the linear ranger was 100~350ng/ml. The fabricated DNA sensors were applied to detect a set of real samples.Chapter Three Detection of the gene of staphylococcal enterotoxin B employing a quartz crystal microbalance biosensorIn this work, a new method t...