Reagentless detection of Mycobacteria tuberculosis H37Ra in respiratory effluents in minutes.
Two similar mycobacteria, Mycobacteria tuberculosis H37Ra and Mycobacteria smegmatis are rapidly detected and identified within samples containing a complex background of respiratory effluents using single-particle aerosol mass spectrometry (SPAMS). M. tuberculosis H37Ra (TBa), an avirulent strain, is used as a surrogate for virulent tuberculosis; M. smegmatis (MSm) is utilized as a near-neighbor confounder for TBa. Bovine lung surfactant and human exhaled breath condensate are used as first-order surrogates for infected human lung expirations from patients with pulmonary tuberculosis. This simulated background sputum is mixed with TBa or MSm and nebulized to produce conglomerate aerosol particles, single particles that contain a bacterium embedded within a background respiratory matrix. Mass spectra of single conglomerate particles exhibit ions associated with both respiratory effluents and mycobacteria. Spectral features distinguishing TBa from MSm in pure and conglomerate particles are shown. SPAMS pattern matching alarm algorithms are able to distinguish TBa-containing particles from background matrix and MSm for >50% of the test particles, which is sufficient to enable a high probability of detection and a low false alarm rate if an adequate number of such particles are present. These results indicate the potential usefulness of SPAMS for rapid, reagentless tuberculosis screening.
Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
Kristl L
KL
Adams
Paul T
PT
Steele
Michael J
MJ
Bogan
Nicole M
NM
Sadler
Sue I
SI
Martin
Audrey N
AN
Martin
Matthias
M
Frank
D000465:Algorithms; D000818:Animals; D001944:Breath Tests; D002417:Cattle; D005740:Gases / Q000032:analysis; D006801:Humans; D013058:Mass Spectrometry; D008954:Models, Biological; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D012119:Respiration; D013997:Time Factors; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis / Q000382:microbiology
D005740:Gases