Advanced Defense Science and Technology
Year:2011 | Volume:2 | Issue:1 (3)|Papers Count:9

Several strains of bacterium produce a biopolymer with different properties. For studying this biopolymer, its relative solubility in organic and inorganic solvents was studied after harvesting it from bacillus culture. Then, using a variety of methods, the coexistence of lipids, sugars and proteins and other compounds in the biopolymer network was examined. Addition of EDTA, sodium hydroxide and dilution of biopolymer solution led to precipitation of some part of this biopolymer as white powder which indicated its polysaccharide properties. The coexistence of polysaccharide and lipids in biopolymer was consequently shown by Mulish and Dyer/or Bligh Test. Adoption of Lowry and Bradford methods showed that the biopolymer composition has been mixed with proteins. Further studies on these proteins were performed by Native & denaturing Electrophoresis & UV-Vis spectroscopy. The results of SDS-PAGE method showed small protein bands with 12-66 kDa in MW. The Native Electrophoresis results indicated that this protein can not run of Electrophoresis due to binding of polymer network by non-covalent bands. Furthermore, the UV-Vis spectroscopy of biopolymer did not show any protein peak. This result indicated that the proteins of biopolymer have been trapped in polymer network. In summary, the results show that this polymer has multi-substance Native.

In this work, sensitive chromogenic reagents were investigated to design a spectrophotometric portable system for determination of uranium in natural waters. It is found that the 2- (5-bromo-2-pyridylazo) -5-diethylaminophenol (Br-PADAP) is the best reagent for this purpose. The effect of various parameters on absorbance of Br-PADAP/ Uranium complex such as pH, masking agent, temperature, time, and uranium concentration were studied and optimized. Based on results obtained, a spectrophotometric portable system for determination of uranium in the field was designed. The results show that the system is able to determine uranium up to 0.5 ppm.

Anthrax caused by Bacillus anthracis, is an acute infectious disease that most commonly occurs in herbivorous animals and human. The vegetative state of Bacillus anthracis has a triplex exotoxin, which consists of three polypeptide: protective antigen (PA, 83 kDa), lethal factor (LF, 90 kDa) and edema factor (EF, 89kDa). PA is considered a primary immunogen for the development of protective immunity against anthrax. This study aims to produce polyclonal antibody in laboratory animals. Domain 4 gene was amplified by PCR from pXOI and inserted into expression plasmid pET28a (+) to create the recombinant pET28a (+) /domain4. The pET28a (+) /domain 4 expression vector confirmed by endonuclease digestion, PCR and sequence analysis. The expression of product domain 4 was confirmed by SDSPAGE. After induced by IPTG, the expression of product domain 4 was analyzed and then was injected to mice and rabbits. All groups received injection four times in 15 days intervals. Finally, the antibody in animals’ sera was confirmed by ELISA and western blotting tests.

“L-Gel” is a decontamination reagent that is effective both against chemical warfare (CW) and biological warfare (BW) agents. This reagent consists of an aqueous solution, Oxone, together with a fumed silica gelling agent Cab-O-Sil EH-5. L-Gel is relatively inexpensive, non-toxic, environmentally friendly, relatively non-corrosive, requires simple delivery system and maximizes contact time due to its thixotropic nature. Experiments to achieve optimized formulation for L-Gel were conducted. Different mixtures of Oxone and Cab-O-Sil were prepared and their viscosity and density were measured. The final optimized formulation of gel included 1.0M aqueous solution of Oxone gelled with 15% W/W of Cab-O-Sil EH-5. A stirring time of 30 minutes was achieved after which viscosity of gel increased over time. To be suitable for decontamination of chemical warfare agents, this formulation should be less viscous and stirred well before use. The effective agent for decontamination is Oxone, in which active ingredient is potassium peroxymonosulfate "KHSO5". The reaction mixture was analyzed by GC and 1H NMR for HD simulants. In 3 minutes, Methyl phenyl sulfide (MPS) was converted to methyl phenyl sulfoxide and methyl phenyl sulfone as decontamination products with a higher reaction rate while chloro ethyl phenyl sulfide (CEPS) was decontaminated with a lower rate leading to chloro ethyl phenyl sulfone in 2 hours.

Filter masks are conventional protective devices for human respiratory system against chemical weapons. Due to the diffusion of some ultra high risk chemical agents through the masks, it is necessary to use the enclosed air breathing system. In other words, human exhalation can be applied with no need to use the contaminated ambient air. In this work, a new system containing three parts (dehumidifier and odorants remover, oxygen generation system (OGS) and COx remover) is proposed and tested which led to the production of 2.5ml/min of O2 from human exhalation. The key step in the system is conversion of CO2 to CO and O2 in OGS. OGS works on the principle of proper solid oxide electrolysis (such as Yttria Stabilized Zirconia or YSZ) which acts as oxygen ion conductor at elevated temperatures. The experiments showed that such system is steadily able to produce 300ml of O2 for at least 2 hours.

In this research, the effect of He/NO2 injection to the post-discharge region of a electric discharge oxygen iodine-laser was studied by using three-dimensional (3D) fluent code. Probable chemical reactions resulted from the presence of He/NO2 in post-discharge region were studied. Effect of He/NO2 combination on keeping the singlet oxygen molecule and depleting atomic oxygen along post-discharge region just before activation region of laser is evaluated. Optimum concentration and flow rate has investigated at special conditions. By changing the injection rate of He/NO2, in the case of 0.25 mmol/s and 2.1 mmol/s rates for NO2 and He, optimum value of injection, about 0.7 m/s, has been obtained.

In this study, the preparation and optimization of spray formulations and aerosolization of Medetomidine hydrochloride as incapacitating agent are investigated. Spray formulation include the drug, solvents (methanol, ethanol and isopropanol), span 85 and propellant (propane). In order for spray preparation, all of the components should form a single phase solution. Results of initial tests and phase behavior of different combination of Medetomidine hydrochloride, alcohol, span 85 and propellant (propane) were checked. The phase behavior of different amount of components was studied and the maximum amount of propane needed for formation of a single-phase solution was determined. Ethanol and isopropanol are more suitable solvents compared to methanol. According to data obtained from different experiments, the optimized formulation with the highest possible concentration of Medetomidine hydrochloride was obtained. Single phase formulation with 5.5% of Medetomidine hydrochloride includes 1g Medetomidine hydrochloride, 10ml of ethanol (44%), 0.25g of span85 (1.4%) and 20ml of propane (49%). This formulation, released from a spray can, led to a stable aerosol.