scholarly journals Detection of Bacillus anthracis Spores Using Peptide Functionalized SERS-Active Substrates

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Atanu Sengupta ◽  
Chetan Shende ◽  
Stuart Farquharson ◽  
Frank Inscore

The need for portable technologies that can rapidly identify biological warfare agents (BWAs) in the field remains an international priority as expressed at the 2011 Biological Weapons Convention. In recent years, the ability of surface-enhanced Raman spectroscopy (SERS) to rapidly detect various BWAs at very low concentrations has been demonstrated. However, in the specific case of Bacillus anthracis, differentiation at the species level is required since other bacilli are common in the environment, representing potential false-positive responses. To overcome this limitation, we describe the use of a peptide attached to the SERS-active metal that selectively binds Bacillus anthracis-Sterne as the target analyte. Using this approach, 109  B. anthracis-Sterne spores/mL produced an intense dipicolinic acid spectrum upon the addition of acetic acid, while the same concentration and treatment of B. cereus and B. subtilis did not.

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 1197
Author(s):  
Xiaoyu Zhao ◽  
Aonan Zhu ◽  
Yaxin Wang ◽  
Yongjun Zhang ◽  
Xiaolong Zhang

In the present study, a sunflower-like nanostructure array composed of a series of synaptic nanoparticles and nanospheres was manufactured through an efficient and low-cost colloidal lithography technique. The primary electromagnetic field contribution generated by the synaptic nanoparticles of the surface array structures was also determined by a finite-difference time-domain software to simulate the hotspots. This structure exhibited high repeatability and excellent sensitivity; hence, it was used as a surface-enhanced Raman spectroscopy (SERS) active substrate to achieve a rapid detection of ultra-low concentrations of Alpha-fetoprotein (AFP). This study demonstrates the design of a plasmonic structure with strong electromagnetic coupling, which can be used for the rapid detection of AFP concentration in clinical medicine.


2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
Hilsamar Félix-Rivera ◽  
Roxannie González ◽  
Gabriela Del Mar Rodríguez ◽  
Oliva M. Primera-Pedrozo ◽  
Carlos Ríos-Velázquez ◽  
...  

The development of techniques that could be useful in fields other than biological warfare agents countermeasures such as medical diagnostics, industrial microbiology, and environmental applications have become a very important subject of research. Raman spectroscopy can be used in near field or at long distances from the sample to obtain fingerprinting information of chemical composition of microorganisms. In this research, biochemical components of the cell wall and endospores of Bacillus thuringiensis (Bt) were identified by surface-enhanced Raman scattering (SERS) spectroscopy using silver (Ag) nanoparticles (NPs) reduced by hydroxylamine and borohydride capped with sodium citrate. Activation of “hot spots”, aggregation and surface charge modification of the NPs, was studied and optimized to obtain signal enhancements from Bt by SERS. Slight aggregation of the NPs as well as surface charge modification to a more acidic ambient was induced using small-size borohydride-reduced NPs in the form of metallic suspensions aimed at increasing the Ag NP-Bt interactions. Hydroxylamine-reduced NPs required slight aggregation and no pH modifications in order to obtain high spectral quality results in bringing out SERS signatures of Bt.


2012 ◽  
Vol 78 (18) ◽  
pp. 6491-6498 ◽  
Author(s):  
Nathalie Morel ◽  
Hervé Volland ◽  
Julie Dano ◽  
Patricia Lamourette ◽  
Patricia Sylvestre ◽  
...  

ABSTRACTBacillus anthracisis one of the most dangerous potential biological weapons, and it is essential to develop a rapid and simple method to detectB. anthracisspores in environmental samples. The immunoassay is a rapid and easy-to-use method for the detection ofB. anthracisby means of antibodies directed against surface spore antigens. With this objective in view, we have produced a panel of monoclonal antibodies againstB. anthracisand developed colorimetric and electrochemiluminescence (ECL) immunoassays. Using Meso Scale Discovery ECL technology, which is based on electrochemiluminescence (ECL) detection utilizing a sulfo-Tag label that emits light upon electrochemical stimulation (using a dedicated ECL plate reader, an electrical current is placed across the microplate with electrodes integrated into the bottom of the plate, resulting in a series of electrically induced reactions leading to a luminescent signal), a detection limit ranging between 0.3 × 103and 103CFU/ml (i.e., 30 to 100 spores per test), depending on theB. anthracisstrain assayed, was achieved. In complex matrices (5 mg/ml of soil or simulated powder), the detection level (without any sample purification or concentration) was never altered more than 3-fold compared with the results obtained in phosphate-buffered saline.


2016 ◽  
Vol 66 (5) ◽  
pp. 464 ◽  
Author(s):  
R.V. Geetha ◽  
Anitha Roy ◽  
S. Senthilkumar ◽  
A.S.B. Bhaskar ◽  
R. Vijayaraghavan

Chemical and biological weapons can be used during conflicts and by terrorists to injure or kill humans and animals. Chemical weapons contain toxic chemicals and biological weapons contain pathogenic organisms. With proper protective equipments and training, the lethal effects of chemical and biological warfare agents can be minimised. First aid kit is available that contain detection, decontamination and medical protection for chemical warfare agents including autoinjectors, for rapid administration and faster absorption of drugs. The autoinjectors are safe and available for life saving drugs like atropine sulphate and pralidoxime chloride (nerve agent poisoning), epinephrine (anaphylaxis), diazepam (seizures) and sumatriptan (migraine). For bio-threat agents doxycycline alone is available as a broad spectrum antibiotic in the first aid kit. Majority of the bacterial agents are gram negative and hence amikacin drug cartridge was developed for the existing autoinjector. The advantage of amikacin is its safety, stability, can be given prophylactically and supplemented with other antibiotics when medical attention arrives. The usability and tolerability of amikacin administered repeatedly through autoinjector was studied using various haematological, biochemical and oxidative stress parameters in animal models. The results are promising and as there is no antibiotic autoinjector available, amikacin autoinjector can be considered for bio-threat agents.


2007 ◽  
Vol 17 (04) ◽  
pp. 719-728 ◽  
Author(s):  
STUART FARQUHARSON ◽  
FRANK E. INSCORE

Protection of military personnel and civilians from water supplies poisoned by chemical warfare agents (CWAs) requires an analyzer that has sufficient sensitivity (μg/L, ppb), specificity (differentiate the CWA from its hydrolysis products), and speed (less than 10 minutes) to be of value. In an effort to meet these requirements, we have been investigating the ability of surface-enhanced Raman spectroscopy (SERS) to detect cyanide and sulfur mustard in water. In our work, we have developed a novel SERS-active material that consists of a porous glass with trapped metal particles. Previously, we coated the inside walls of glass vials and measured cyanide at 1 mg/L in water in as little as 1 minute. However, measurements of sulfur mustard have only been measured to 10 mg/L. Recently, we filled glass capillaries with the SERS-active material. Here we describe measurements of cyanide, sulfur mustard, and it's hydrolysis product, thiodiglycol, using these capillaries and a portable Raman analyzer suitable for point and continuous water monitoring.


2004 ◽  
Vol 26 (2) ◽  
pp. 15-17
Author(s):  
Jeremy Mogridge

The intentional release of Bacillus anthracis spores in the USA during the autumn of 2001 alerted the public to the possibility of future attacks using biological weapons. It also underscored the importance of understanding the pathogenesis of the organism and the need for developing new therapeutics and vaccines. Fortunately, there has been a resurgence in anthrax research. This review focuses on the characteristics of B. anthracis that have led to its use as a biological weapon and the approaches that are being taken by medical researchers to minimize the impact of another release.


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