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Introduction

The BioHawk is a portable 8-channel bioassay system with automated sample collection capability that is suitable for high-sensitivity monitoring of biological agents, toxins, explosives, and chemical contaminants. Biohawk can be programmed to continuously or intermittantly monitor surrounding air for aerosol threats with its built-in air sampler, and to periodically transfer a wet concentrate from the air sampler to the built-in biodetector. Assay results for the eight detection channels are typically available 10 to 15 minutes after liquid sample introduction.

The biodetector portion of the instrument will also accept fluids for analysis from other sample collection systems, or will process liquid samples loaded into the instrument manually. A built-in microcomputer provides unparalleled operating flexibility and sophistication.

Bioassays are performed within a small disposable credit card-sized plastic assay coupon. Unlike other technologies on the market that are based on a "use once and discard" philosophy, this coupon and the reagents stored within it may be used for 10 or more assay procedures before being discarded. Since a single assay coupon can handle up to eight different assays simultaneously, this means that up to 80 individual assays may be performed before the coupon is discarded. This capability can substantially reduce life cycle cost.

Assay results may be transmitted to users through the touch panel LCD display, an audible alarm, a pulsating light, or by wireless or RS-232 link to personnel at a remote location. System operation may also be remotely controlled in real time- virtually every fluid or air handling function is capable of being operated remotely.

While possessing a high level of function and great versatility, the unit is still very easy to use. Most global functions such as air sampling and biodetection are performed using multi-step recipes developed by Research International and stored in the system's computer memory. The unsophisticated user needs only the most fundamental level of training since the internal processes and steps are preset through the built-in computerized recipes. For more professional users, bundled Windows-based software allows the user to develop his own customized sample collection and detection protocols.

The system is truly portable at a field weight of only 12.1 kg and volume of 17 liters. The system is capable of 12 to 24 hours of operation on the standard BA5590/U primary battery or UBI 2590 rechargeable battery: Specific operating time will depend on climatic conditions and use profile. In the following sections, the air sampler and biodetector technologies are described in greater detail.

• Download BioHawk Data Sheet (440KB, PDF)

Air Sampler Features

The air sampler is a highly effective multi-stage wetted-wall cyclone that continuously processes air at a 325 LPM rate, extracting particulates and transferring them to a liquid phase of 4 to 5 cc volume (see Figure 2). Distilled water is typically the liquid of choice; no additives or surfactants are required for maximum efficiency. This liquid portion may then be periodically transferred in part or in whole to the biodetector, using a built-in peristaltic pump. A dropper bottle filling station is also integrated into the BioHawk so that a portion or all of the sample may be dispensed into the dropper bottle for archiving and/or application of an alternative analysis method. For example, the dropper bottle feature allows the BioHawk to be used as a sample collection and preparation system for lateral flow tickets. Unique and patented features of the air sampler include its abilities to operate unattended for long periods of time and to amplify trace analyte concentrations by maintaining a user-selected sample fluid volume in the device, independent of collection time, air temperature or relative humidity.

This is accomplished by monitoring liquid inventory with a proprietary sensor attached to the cyclone body. When the sample water inventory falls below the set point, the sensor initiates clean water transfer into the cyclone body from an onboard 1 liter water supply. Water inventories may be maintained within a recommended range of about 4 cc to 5 cc with an accuracy of a few tenths of a cubic centimeter.

Figure 2: Air sampler flow schematic.

Biodetector Description

The instrument's biodetector section consists of a disposable 8-channel fluorometric assay coupon (see Figure 3) suitable for the high-sensitivity detection of biological agents, toxins, explosives, and chemical contaminants. All target-specific reagents needed to perform an assay are contained within the coupon. The only fluid not carried in the coupon is a saline buffer used to wash the system between assays. It is stored within a refillable reservoir in the instrument and a waste water reservoir is also provided. This ensures that no fluids are discharged from the instrument during either air sampling or the bioassay step.

Figure 3: BioHawk bioassay coupon.

Upon coupon insertion into the instrument, an optical bar code on the coupon is automatically interrogated for assay recipe information. Highly reliable computer-controlled peristaltic and syringe pumps are used to move reagents, sample fluids and wash buffer within the coupon, as directed by the assay recipe. Automation of the assay process in this way ensures repeatable behavior from test to test.

Targeted agents are detected by monitoring fluorescently-tagged chemical reporter reactions taking place on optical waveguide surfaces within the coupon (see Figure 4). These reactions typically use antibodies to bind targeted pathogens to the waveguide surfaces, and fluorophore-tagged secondary antibodies to create a fluorescent signal when the waveguides are irradiated with 635 nm solid state laser light. See the RAPTOR Sandwich Assays chart for additional information on waveguide-based biosensing and analytes that can be detected with this type of approach.

Assay data is automatically stored in the system's non-volatile EEPROM with a date and time stamp, and can be downloaded to a remote computer using an RS-232 or wireless link. The BioHawk has the capacity to save up to 6,000 data sets.

Auxiliary Windows-based software allows the user to graphically monitor data recovery while an assay is running. It also provides sophisticated users with the ability to customize the various steps involved in running an assay.

Figure 4: Evanescent wave biodetection process.

Figure 5: BioHawk components (front view illustration).

Figure 5: BioHawk components (back view illustration).

This product is covered by one or more of the following patents: U.S. Patents No. 6,136,611; 5,430,813; 6,082,185; 6,532,835; 5,061,857; and Japanese Patents No. 3,429,282 and 3,754,440.

Application Areas:

• Medical
• Agriculture
• Military
• Homeland security
• Environmental
• Indoor air quality

Features:

• Man portable. Measures:35.6 cm W x 36.5 cm H x 17.1 cm D. Weighs less than 30 pounds.
• Air sampler uses multi-stage, wetted-wall cyclone principle for enhanced particulate collection.
• Air collection at 325 LPM, nominal.
• Uses disposable wet assay coupon. Reusable up to 15 times. Eight simultaneous assays.
• Fast assays: 10 - 15 minutes typical.
• Auto-flush protocols for decontamination.
• Analyte range: toxins, bacteria, spores, fungi, multi-cellular pathogens.
• Sensitivity: analyte dependent, 1 to 10 ppb typical for toxins, 100 to 100,000 CFU/ml for bacteria.
• Operator interface: Day / night touch screen LCD.
• Designed to MILSPEC 810F.
• Flash memory retains raw / processed data for over 6,000 assays.

Product information:

• BioHawk Frequently Asked Questions
  
  
• BioHawk Parts and Accessories Page
  
  
• View Product bibliography
  
  
• Download Data Sheet (440KB, PDF)
  
  
• Power Measurements and Battery Life Estimates (92 KB, PDF)
  
  
• Candidate Disinfectants for Research International Products (978 KB, PDF)
  
  
• Bluetooth Biolink™ Wireless Units provide plug-and-play wireless communication between any Research International product and a remote PC or laptop.
  

Contact Us :

• Call Toll Free at 1-800-927-7831

• Send E-mail

• Or Request a Quote

Research International, Inc. • 17161 Beaton Road SE • Monroe, WA 98272
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