Low-Level Detection of a Bacillus Anthracis Simulant using Love-Wave Biosensors on 36 Degree YX LiTaO3

Technical Report · Sat Mar 01 04:00:00 EST 2003

DOI:https://doi.org/10.2172/820881· OSTI ID:820881

BRANCH, DARREN W ^[1]; BROZIK, SUSAN M

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1. Sandia National Laboratories

Crucial to low-level detection of biowarfare agents in aqueous environments is the mass sensitivity optimization of Love-wave acoustic sensors. The present work is an experimental study of 36{sup o} YX cut LiTaO{sub 3} based Love-wave devices for detection of pathogenic spores in aqueous conditions. Given that the detection limit (DL) of Love-wave based sensors is a strong function of the overlying waveguide, two waveguide materials have been investigated, which are polyimide and polystyrene. To determine the mass sensitivity of Love-wave sensor, bovine serum albumin (BSA) protein was injected into the Love-wave test cell while recording magnitude and phase shift across each sensor. Polyimide had the lowest mass detection limit with an estimated value of 1-2 ng/cm{sup 2}, as compared to polystyrene where DL = 2.0 ng/cm{sup 2}. Suitable chemistries were used to orient antibodies on the Love-wave sensor using adsorbed protein G. The thickness of each biofilm was measured using ellipsometry from which the surface concentrations were calculated. The monoclonal antibody BD8 with a high degree of selectivity for anthrax spores was used to capture the non-pathogenic simulant B. thuringiensis B8 spores. Bacillus Subtilis spores were used as a negative control to determine whether significant non-specific binding would occur. Spore aliquots were prepared using an optical counting method, which permitted removal of background particles for consistent sample preparation. This work demonstrates that Love-wave devices can be used to detect B. anthracis simulant below reported infectious levels.

• Research Organization: Sandia National Labs., Albuquerque, NM (US); Sandia National Labs., Livermore, CA (US)
• Sponsoring Organization: US Department of Energy (US)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 820881
• Report Number(s): SAND2003-0695
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
60 APPLIED LIFE SCIENCES
ACOUSTICS
ALBUMINS
ANTIBODIES
BACILLUS
BACILLUS SUBTILIS
CATTLE
DETECTION
ELLIPSOMETRY
OPTIMIZATION
PHASE SHIFT
POLYSTYRENE
PROTEINS
SAMPLE PREPARATION
WAVEGUIDES