Bacillus anthracis spores are a potential threat to countries in the context of biodefense. We have already seen the destructiveness of the anthrax attacks in the recent past. This study presents an aminated-poly(vinyl chloride) (PVC-NH2) coated quartz crystal microbalance (QCM) immunosensor for simultaneous rapid detection of B. anthracis spores. PVC-NH2, synthesized in the laboratory, was used as an adhesive layer for monoclonal antibody immobilization on gold quartz crystal. The prepared QCM sensor was tested using a pathogen field strain of B. anthracis (GenBank number: GQ375871.1) under static addition and flow through procedures with different spore concentrations. Fourier transform infrared spectroscopy (FTIR-ATR) and scanning electron microscopy (SEM) were performed to characterize the surface of the sensor during the modification. Furthermore, a series of SEM micrographs were taken in order to investigate surface morphology and show the presence of the B. anthracis spores on the surface. It is concluded that B. anthracis spores can be accomplished by using amine functionalized polymer coated QCM sensors without requiring complicated immobilization procedures or expensive preliminary preparations. 1. Introduction Bacillus anthracis, the etiological agent of anthrax, is a spore-forming bacterium. Dormant spores are highly resistant to adverse conditions including heat, ultraviolet and ionizing radiation, pressure, and chemical agents. They are able to survive for long periods in contaminated soils and thus account for the ecological cycle of the organism. In a suitable environment spores reestablish vegetative growth [1, 2]. There are three types of human anthrax known: gastrointestinal, cutaneous, and inhalation anthrax. The most dangerous form, inhalational anthrax, results from inhalation of spores aerosolized in sufficiently small particle sizes (5–10？μm) to reach the alveoli. The inhalation anthrax is the most severe one because 99% casualties occurred in individuals who were not treated before symptoms developed [3]. The threat of B. anthracis spores as a bioterrorism agent has created an urgent need for a rapid real-time, highly selective, and sensitive technique to detect the presence of anthrax spores. The traditional methods for B. anthracis detection are primarily based on bacteriological, serology-immunological, and genetic methods [4]. Most of these methods are labouring and time consuming, especially traditional approaches which involve the growing of the microorganism on selective media for at least 24？h followed by morphological
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