Biomedical subjects

Mary T McBride

Publications and source records attributed to Mary T McBride.

8 recordsLinked to original sources

PubMed2006

Multiplexed detection of antibodies to nonstructural proteins of foot-and-mouth disease virus.

Liquid array technology was used to develop a multiplexed assay for the detection of antibodies to viral nonstructural proteins (NSPs), raised in cattle in response to infection with foot-and-mouth disease (FMD) virus. Two assays, one based on recombinant NSPs and the other on synthetically produced peptides, were developed and compared side-by-side. Serum samples from serial bleeds of cattle, each experimentally infected with one of the seven serotypes (C, A, O, Asia, SAT1, SAT2, SAT3) of FMD virus were analyzed. A distinct pattern in the detection of NSP antibodies and a close correlation of the recombinant protein and peptide-based assays were observed. The detection of antibodies to NSPs is a method to differentiate FMD-infected and FMD-vaccinated animals, and a high-throughput assay would be an invaluable tool in the case of an outbreak of FMD in North America, when emergency vaccination may be utilized to spare vaccinated, noninfected animals from slaughter and subsequent disposal.

Animals↗

PubMed2005

Fabricating optical fiber imaging sensors using ink jet printing technology: a pH sensor proof-of-concept.

We demonstrate the feasibility of using Drop-on-Demand microjet printing technology for fabricating imaging sensors by reproducibly printing an array of photo-polymerizable sensing elements, containing a pH sensitive indicator, on the surface of an optical fiber image guide. The reproducibility of the microjet printing process is excellent for microdot (i.e. micrometer-sized polymer) sensor diameter (92.2+/-2.2 microm), height (35.0+/-1.0 microm), and roundness (0.00072+/-0.00023). pH sensors were evaluated in terms of pH sensing ability (< or =2% sensor variation), response time, and hysteresis using a custom fluorescence imaging system. In addition, the microjet technique has distinct advantages over other fabrication methods, which are discussed in detail.

Biosensing Techniques↗

PubMed2005

APDS: the autonomous pathogen detection system.

We have developed and tested a fully autonomous pathogen detection system (APDS) capable of continuously monitoring the environment for airborne biological threat agents. The system was developed to provide early warning to civilians in the event of a bioterrorism incident and can be used at high profile events for short-term, intensive monitoring or in major public buildings or transportation nodes for long-term monitoring. The APDS is completely automated, offering continuous aerosol sampling, in-line sample preparation fluidics, multiplexed detection and identification immunoassays, and nucleic acid-based polymerase chain reaction (PCR) amplification and detection. Highly multiplexed antibody-based and duplex nucleic acid-based assays are combined to reduce false positives to a very low level, lower reagent costs, and significantly expand the detection capabilities of this biosensor. This article provides an overview of the current design and operation of the APDS. Certain sub-components of the ADPS are described in detail, including the aerosol collector, the automated sample preparation module that performs multiplexed immunoassays with confirmatory PCR, and the data monitoring and communications system. Data obtained from an APDS that operated continuously for 7 days in a major U.S. transportation hub is reported.

Aerosols↗

PubMed2005

Autonomous detection of aerosolized biological agents by multiplexed immunoassay with polymerase chain reaction confirmation.

The autonomous pathogen detection system (APDS) is an automated, podium-sized instrument that continuously monitors the air for biological threat agents (bacteria, viruses, and toxins). The system has been developed to warn of a biological attack in critical or high-traffic facilities and at special events. The APDS performs continuous aerosol collection, sample preparation, and detection using multiplexed immunoassay followed by confirmatory PCR using real-time TaqMan assays. We have integrated completely reusable flow-through devices that perform DNA extraction and PCR amplification. The fully integrated system was challenged with aerosolized Bacillus anthracis, Yersinia pestis, Bacillus globigii, and botulinum toxoid. By coupling highly selective antibody- and DNA-based assays, the probability of an APDS reporting a false positive is extremely low.

Aerosols↗

PubMed2004

Development of an automated sample preparation module for environmental monitoring of biowarfare agents.

An automated sample preparation module, based upon sequential injection analysis (SIA), has been developed for use within an autonomous pathogen detection system. The SIA system interfaced aerosol sampling with multiplexed microsphere immunoassay-flow cytometric detection. Metering and sequestering of microspheres using SIA was found to be reproducible and reliable, over 24-h periods of autonomous operation. Four inbuilt immunoassay controls showed excellent immunoassay and system stability over five days of unattended continuous operation. Titration curves for two biological warfare agents, Bacillus anthracis and Yersinia pestis, obtained using the automated SIA procedure were shown to be similar to those generated using a manual microtiter plate procedure.

Antibodies, Bacterial↗

PubMed2003

Autonomous detection of aerosolized Bacillus anthracis and Yersinia pestis.

We have developed and tested a fully autonomous pathogen detection system (APDS) capable of continuously monitoring the environment for airborne biological threat agents. The system is designed to provide early warning to civilians in the event of a terrorist attack. The final APDS will be completely automated, offering aerosol sampling, in-line sample preparation fluidics, multiplexed detection and identification immunoassays, and orthogonal, multiplexed PCR (nucleic acid) amplification and detection. The system performance (current capabilities include aerosol collection, multiplexed immunoassays, sample archiving, data reporting, and alarming) was evaluated in a field test conducted in a Biosafety Level 3 facility, where the system was challenged with, and detected, a series of aerosolized releases containing two live, virulent biological threat agents (Bacillus anthracis and Yersinia pestis). Results presented here represent the first autonomous, simultaneous measurement of these agents.

Aerosols↗

PubMed2003

Multiplexed liquid arrays for simultaneous detection of simulants of biological warfare agents.

Liquid array-based multiplexed immunoassays designed for rapid, sensitive, specific, and simultaneous detection of multiple simulants of biological warfare agents have been developed. In both blind and standard laboratory trials, we demonstrate the simultaneous detection of four simulant agents from a single sample. The challenge agents comprise broad classes of pathogens (virus, protein toxins, bacterial spores, vegetative cells). Assay performance of each analyte was optimized, and dose-response curves and the limits of detection (LODs) for individual analytes are presented. Assay performance, including dynamic range, sensitivity, and LODs for liquid arrays and enzyme-linked immunosorbant assay were compared and are shown to be similar. Maximum assay sensitivity is obtained in approximately 1 h, and good sensitivity is achieved in as little as 30 min. Although the sample matrixes are very complex, even for highly multiplexed assays the samples do not exhibit evidence of nonspecific binding, demonstrating that the assays also have high specificity.

Bacteria↗

PubMedDate not supplied

Comparison of multiplexed techniques for detection of bacterial and viral proteins.

Immobilized antibody microarrays were compared to the Luminex flow cytometry system that utilizes suspensions of polystyrene microbeads covalently coupled with capture antibodies. The two immunoassays were performed for comparison of reproducibility, limits of detection and dynamic range. The Luminex system showed lower limits of detection and increased dynamic range among samples whereas the protein microarrays could be more amenable to miniaturization. Both technologies were capable of sensitive multiplexed detection.

Antibodies, Bacterial↗