Evaluation of a micro-fabricated pyrolyzer for the detection of Bacillus anthracis spores

Recent applications in analytical thermochemolysis

“…Voorhees and co-workers [34] fabricated a micro-pyrolyzer interfaced to a quadrupole ion trap mass spectrometer for the thermochemolysis-TMAH of Bacilus anthracis spores. The micropyrolyzer device consisted of a silicon water substrate with a silicon-nitride membrane heated by a platinum resistive element.…”

“…A combination of analytical pyrolysis and thermochemolysis-TMAH was used in the analysis of Bacillus anthracis spores [177]. Thermochemolysis showed the presence of dipicolinic acid dimethyl ester.…”

One-step conversion of dipicolinic acid to its dimethyl ester using monomethyl sulfate salts for GC-MS detection of bacterial endospores

“…UV absorbance of extracted samples separated by LC tetramethylammonium hydroxide (TMA-OH) at temperatures ranging from 358-770 C, two key desired biomarker products being the DPA dimethyl ester, Me 2 DPA (3 in Scheme 1), and fatty acid methyl esters (FAMEs). 32,34,[40][41][42] Limits of detection by this method are comparable to those of direct pyrolysis. Spores pyrolyzed at 460 C ahead of a triple quadrupole MS instrument in the presence of TMA-OH gave an Me 2 DPA-based LOD of 2 Â 10 7 colony forming units (CFUs) per mL.…”

“…Hence, quantitative production of Me 2 DPA (3) is unlikely. Although inclusion of a methylation reagent greatly protects from loss of the carboxylate groups, 32,[40][41][42] if MeMPA is formed, it results in loss of Me 2 DPA sensitivity. Second, cations such as the abundant, DPA-chelated Ca 2+ poison the methylation of anionic carboxylate groups by inhibiting the ion pair formations between (cationic) methylation reagents requisite for good S N 2 methylation efficiency.…”

Metal-organic frameworks as biosensors for luminescence-based detection and imaging

“…Therefore, the detection of these spores through DPA sensing would be important in preventing bioterrorism attacks. While many techniques have been used to detect DPA, including spectrophotometry [ 45 ], Raman spectroscopy [ 46 ], pyrolysis mass spectrometry [ 47 ], high-performance liquid chromatography [ 48 ], potentiometric sensing [ 49 ] and capillary zone electrophoresis [ 50 ], these suffer from high costs, the need for large instruments, and time-consuming and complicated analysis. Nanoparticle-based sensors are promising as smaller, faster, simpler, and therefore more efficient alternatives to these methods.…”