Hardware development was supported by the NASA SBIR Contracts NNX09CA44C and NNX10CA97C. Data analysis for the optical block and sample loader demonstrations was supported by NASA Phase III Contract NNC11CA04C. The human blood collection was performed using NASA IRB Protocol # SA-10-008. Control/acquisition software provided through the National Instruments Medical Device Grant Program. Molds for the microchips were made at the Johns Hopkins microfabrication facility and the Harvard Center for Nanoscale Systems. Otto J. Briner and Luke Jaffe (DNA Medicine Institute) aided in rack assembly during summer 2010. NASA flight video staff provided video footage during flight week. Carlos Barrientos (DNA Medicine Institute) provided photograph and figure assistance. Special thanks to the Facilitated Access to the Space Environment for Technology 2010 Program, the NASA Reduced Gravity Office, the Human Adaptation and Countermeasures Division, NASA Glenn Research Center, ZIN Technologies, and the Human Research Program.

<ol>
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Eugene Y. Chan, Candice Bae, and Julia Z. Sharpe are inventors on related technology patents filed through the DNA Medicine Institute, a commercial entity.

The method described here enabled effective demonstration of the major technology components (sample loading, microfluidic mixing, and optical detection) during the 2010 FAST parabolic flights, with comparable results to ground testing. Training and SOP methods described here were particularly effective, and helped to illuminate tools and other &#8216;crutches&#8217; being relied on for practice demonstrations that would not be available onboard the parabolic flight.
Areas for improvement incl...

The inadequacy of current space-ready health diagnostics presents a limiting factor to deeper manned space exploration. Diagnostics need to be comprehensive, easy to use in reduced gravity, and relatively unaffected by the stresses of launch and spaceflight (e.g., high g-forces, vibration, radiation, temperature changes, and cabin pressure changes). Developments in point-of-care testing (POCT) may translate to effective spaceflight solutions through the use of smaller patient specimens (e.g., a finger prick), simpler and smaller fluidics (i.e., microfluidics), and reduced electrical power requirements, among other advantages. Flow cytometry is one attractive approach for in-space POC because of the broad utility of the technology, including toward cell counting and biomarker quantification, as well as significant miniaturization potential. Previous space-relevant flow cytometers include the &#8216;nuclear packing efficiency&#8217; (NPE) instrument that utilized simultaneous arc-lamp induced fluorescence and electronic volume (Coulter volume) measurement 1-4, a relatively small benchtop flow cytometer representing the &#8216;first generation of real-time flow cytometry data during zero gravity&#8217; 5, a &#8216;sheathless microflow cytometer&#8217; capable of 4- and 5-part white blood cell (WBC) differential count using pretreated 5 &#181;l whole blood samples 6-9, and a &#8216;fiber-optic-based&#8217; flow cytometer recently tested onboard in the International Space Station 10.
Evaluating diagnostic technology for potential space applications is typically performed onboard reduced-gravity aircraft that use an approximately parabolic flight trajectory to simulate a chosen level of weightlessness (e.g., zero-gravity, martian-gravity) 11. Evaluation is challenging because flight opportunities are limited, repetitive short windows of microgravity can make it difficult to assess methodologies or processes that normally require uninterrupted periods longer than 20-40 sec, and demonstrations may require additional equipment not easily utilized in-flight 12-15. Furthermore, previous demonstrations of in vitro diagnostic (IVD) technologies used in, or designed for, reduced gravity are limited and much work remains unpublished. In addition to the above flow cytometers, other space-relevant IVD-technologies described in the literature include a whole blood staining device for immunophenotyping applications 16, an automated camera-based cytometer 12, a handheld clinical analyzer for integrated potentiometry, amperometry, and conductometry 12,17, a microfluidic &#8216;T-sensor&#8217; device for analyte quantitation that relies on diffusion-based mixing and separation 18, and a rotating &#8216;lab on a CD&#8217; diagnostics platform 19,20. Newcomers to reduced gravity testing may also look to parabolic flight demonstrations unrelated to in vitro diagnostics when attempting to make device evaluation possible (or figuring out what is possible). Demonstrations from other previous medical or biological experimentation with well-documented flight preparation, in-flight strategies, and flight test equipment are included in Table 115, 21-35. These may be informative due to inclusion of manual in-flight tasks, use of specialized equipment, and experimental containment.
<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr height="17">
			<td height="17" style="height:17px;width:133px;">Category</td>
			<td style="width:497px;">Examples</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:133px;">Emergency medical care</td>
			<td style="width:497px;">Tracheal intubation (laryngoscope-guided, on manikin) 21, cardiac life support (anesthetized pigs) 22</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:133px;">Surgical care</td>
			<td style="width:497px;">Laparoscopic surgery (video simulated 23, on anesthetized pigs 24,25)</td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:133px;">Medical imaging or physiology assessment</td>
			<td style="width:497px;">Ultrasound with lower body negative pressure chamber 26, Doppler flowmeter (head mounted) 27, central venous pressure monitor 28</td>
		</tr>
		<tr height="65">
			<td height="65" style="height:65px;width:133px;">Specialized biological equipment</td>
			<td style="width:497px;">Microplate reader (and in-flight glove box) 29, temperature control system for cell cycle experiments 30, microscope (brightfield, phase contrast, and multi-channel fluorescence capable) 15, capillary electrophoresis unit coupled to video microscope 31</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:133px;">Other</td>
			<td style="width:497px;">Plant harvesting with forceps 32, contained rats 33,34 and fish 35 for observation</td>
		</tr>
	</tbody>
</table>
Table 1. Parabolic Flight Demonstration Examples with Well Described Methods/Experiments
To expand on previous examples and provide greater insight into successful in-flight demonstrations, we are presenting a modular and adaptable procedure for construction and operation of a prototype flow cytometer with related microfluidic mixing technology as part of a parabolic flight test rig. The rig enables demonstrations of sample loading, microfluidic mixing, and fluorescent particle detection, and was tested onboard the 2010 NASA Facilitated Access to the Space Environment (FAST) parabolic flights, flown from September 29 to October 1, 2010. These demonstrations pull from the beginning, middle, and end, respectively of a potential device workflow in which fingerstick-sized blood samples are loaded, diluted or mixed with reagents, and analyzed via optical detection. Scaling a flow cytometer into a compact unit requires innovation and careful part selection. Custom and off-the-shelf components are used here, chosen as best early approximations of final component choices, and may be adaptable to the designs of other innovators. Following an outline of prototype component choices, setup is described on a support structure serving as a skeleton for rig assembly. Prototype components are assigned locations, secured, and accompanied by additional components necessary for successful experimentation. Attention then shifts to more abstract procedures involving standard operating procedure (SOP) development, training, and other logistics. Finally, demonstration-specific procedures are described. The strategies described here and the choices of supporting rig components (e.g., microscope, acrylic box, etc.), although implemented here for specific prototype, speak to the general issues and challenges relevant to testing any blood diagnostic equipment in a reduced-gravity environment.
In the 2010 flights, two lunar-gravity (achieving approximately 1/6 earth gravity)and two micro-gravity flights were scheduled across 4 days, although ultimately these were rescheduled across 3 days. Demonstrations were performed onboard a modified privately operated, narrow-body jet airliner 36. Each flight provided 30-40 parabolas, each yielding about 20 sec of high-gravitation (roughly 1.8 g) followed by 20-25 sec of reduced-gravity conditions. After half of the parabolas were executed, the plane paused for a period of about 5-10 min in level flight to enable the plane to turn around and head back toward the landing site while performing the remainder of the parabolas.

<table border="0" cellpadding="0" cellspacing="0" width="1933">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">Name of Material/ Equipment</td>
			<td style="width:287px;">Company</td>
			<td style="width:135px;">Catalog Number</td>
			<td style="width:1143px;">Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">Micro air pump</td>
			<td style="width:287px;">Smart Products, Inc.</td>
			<td style="width:135px;">AP-2P02A</td>
			<td>Max pressure = 6.76 psi; 1.301&#8221; x 0.394&#8221; x 0.650&#8221; , 0.28 oz (8 g); available direct from Smart Products</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Differential pressure sensor</td>
			<td style="width:287px;">Honeywell International, Inc.</td>
			<td style="width:135px;">ASDX015D44R</td>
			<td>Range&#160; of&#160; 0-15psi; 0.974&#34; x 0.550&#34; x 0.440&#34;, 0.09 oz (2.565 g); suppliers include Digi-Key and Mouser Electronics</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Rigid plastic vial (small size)</td>
			<td style="width:287px;">Loritz &#38; Associates, Inc.</td>
			<td style="width:135px;">55-05</td>
			<td>Polystyrene; ID 0.81&#34; (20.6 mm), IH 2.06&#34; (52.4 mm); available direct from LA Container Inc.; similar product available from Dynalab Corp.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Rigid plastic vial (larger size)</td>
			<td style="width:287px;">Loritz &#38; Associates, Inc.</td>
			<td style="width:135px;">55-140</td>
			<td>Polystyrene; ID 1.88&#34; (47.6 mm), IH 3.31&#34; (84.1 mm); available direct from LA Container Inc.; similar product available from Dynalab Corp.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">latex examination gloves</td>
			<td style="width:287px;">dynarex corporation</td>
			<td style="width:135px;">2337</td>
			<td>Middle finger used for latex diaphragm in fluid source vial.&#160; Other brands (e.g., Aurelia &#174;&#160; Vibrant &#8482;) acceptable.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Optical glue</td>
			<td style="width:287px;">Norland Products</td>
			<td style="width:135px;">NOA 88</td>
			<td>Low outgassing adhesive; available direct from Norland; Also available from Edmund Optics Inc.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">3-way solenoid valves</td>
			<td style="width:287px;">The LEE Company</td>
			<td style="width:135px;">LHDA0531115H</td>
			<td>Gas valves, but can function with liquid; 1.29 &#34; L, 0.28 &#34; D.&#160; Discontinued product.&#160; Similar products available from The LEE Company.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">Volumetric water flowmeter</td>
			<td style="width:287px;">OMEGA Engineering inc.&#160;</td>
			<td style="width:135px;">FLR-1602A</td>
			<td>Non-contacting flow rate meter strongly preferred.&#160; We recommend SENSIRION LG16 OEM Liquid Flow Sensor for flow rates from nl/min up to 5 ml/min.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">PCD-mini photon detector&#160;</td>
			<td style="width:287px;">Sensl</td>
			<td style="width:135px;">PCDMini-00100</td>
			<td style="width:1143px;">For fluorescence detection; available direct from Sensl</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">Accelerometer</td>
			<td style="width:287px;">Crossbow Technology, Inc.</td>
			<td style="width:135px;">CXL02LF3</td>
			<td>3-demensional force detection.&#160; Supplied to DMI by NASA.&#160; Similar product available from Vernier Software &#38; Technology, LLC.&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">Stereomicroscope</td>
			<td style="width:287px;">AmScope</td>
			<td style="width:135px;">SE305R-AZ-E</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">CCD Camera</td>
			<td style="width:287px;">Thorlabs</td>
			<td style="width:135px;">DCU223C</td>
			<td>1024 x 768 Resolution, Color, USB 2.0; available direct from Thorlabs</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">USB and Trigger Cable (In/Out) for CCD Camera</td>
			<td style="width:287px;">Thorlabs</td>
			<td style="width:135px;">CAB-DCU-T1</td>
			<td>Available direct from Thorlabs</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Microbore tubing</td>
			<td style="width:287px;">Saint-Gobain Corporation</td>
			<td>AAD04103</td>
			<td>Tygon&#174;; ID 0.02&#34;, OD 0.06&#34;, 500ft, 0.02&#34; wall. Suppliers: VWR, Thermo Fisher Scientific Inc.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Hollow steel pins</td>
			<td style="width:287px;">New England Small Tube</td>
			<td style="width:135px;">(Custom)</td>
			<td>&#160;0.025&#34; OD, 0.017&#34; ID, 0.500&#8221; L, stainless steel tube, type 304, cut, deburred, passivated; enable microbore tubing connections, chip tubing connections</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">Slide clamp</td>
			<td style="width:287px;">World Precision Instruments, Inc.</td>
			<td style="width:135px;">14042</td>
			<td>Available direct from World Precision Instruments</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">Leur adaptor pieces</td>
			<td style="width:287px;">World Precision Instruments, Inc.</td>
			<td style="width:135px;">14011</td>
			<td>Available direct from World Precision Instruments</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Silicon wafer</td>
			<td style="width:287px;">Addison Engineering, Inc.</td>
			<td style="width:135px;"></td>
			<td>6&#34; diameter; for SU-8 mold fabrication</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:23px;width:368px;">Polydimethylsiloxane (PDMS) elastomer base</td>
			<td style="width:287px;">Dow Corning</td>
			<td style="width:135px;">3097366-1004</td>
			<td>Supplier: Global Industrial SLP, LLC</td>
		</tr>
		<tr height="18">
			<td height="18" style="height:19px;width:368px;">Polydimethylsiloxane (PDMS) elastomer curing agent</td>
			<td style="width:287px;">Dow Corning</td>
			<td style="width:135px;">3097358-1004</td>
			<td>Supplier: Global Industrial SLP, LLC</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Needle (23 gauge), bevel tip</td>
			<td style="width:287px;">Terumo Medical Corporation</td>
			<td style="width:135px;">NN-2338R</td>
			<td>Ultra thin wall; 23G x 1.5&#34;; 22G also usable; suppliers: Careforde, Inc.,&#160; Port City Medical</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Dispensing needle (23 gauge), blunt tip</td>
			<td style="width:287px;">CML Supply</td>
			<td style="width:135px;">901-23-100</td>
			<td>23Gx 1&#34;;&#160; available from CML Supply</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Rotary tool</td>
			<td style="width:287px;">Robert Bosch Tool Corporation</td>
			<td style="width:135px;">1100-01</td>
			<td>Dremel&#174; 1100-01 Stylus&#8482;&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">Cover glass</td>
			<td style="width:287px;">Thermo Fisher Scientific, Inc.</td>
			<td style="width:135px;">12-518-105E</td>
			<td>Gold Seal&#8482; noncorrosive borosilicate glass; for PDMS chip cover; 24x60 mm; available from Thermo Fisher Scientific, Inc.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Vacuum pump</td>
			<td style="width:287px;">Mountain</td>
			<td style="width:135px;">MTN8407</td>
			<td>For degassing PDMS; supplier:&#160; Ryder System, Inc.&#160;</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Vacuum chamber</td>
			<td style="width:287px;">Thermo Fisher Scientific, Inc.</td>
			<td style="width:135px;">5311-0250</td>
			<td>Nalgene&#8482; Transparent Polycarbonate; available from Thermo Fisher Scientific, Inc.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Plasma cleaner</td>
			<td style="width:287px;">Harrick Plasma</td>
			<td style="width:135px;">PDC-32G</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Hand magnifier</td>
			<td style="width:287px;">Mitutoyo</td>
			<td style="width:135px;">183-131</td>
			<td>Use in reverse direction to enable viewing at ~15&#34;.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Ethanol</td>
			<td style="width:287px;">CAROLINA</td>
			<td style="width:135px;">861283</td>
			<td>For chip cleaning. Dilute to 70% using millipore water.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Water purification system</td>
			<td style="width:287px;">Thermo Fisher Scientific, Inc.</td>
			<td style="width:135px;">D11901</td>
			<td>Available direct from Thermo Fisher Scientific, Inc.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Optomechanical translation mounts</td>
			<td style="width:287px;">Thorlabs</td>
			<td style="width:135px;">K6X</td>
			<td>6-Axis Kinematic Optic Mount; discontinued product; new product (K6XS) available direct from Thorlabs</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">Laptop</td>
			<td style="width:287px;">Hewlett-Packard</td>
			<td style="width:135px;">VP209AV</td>
			<td>HP Pavilion Laptop running Windows 7</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">Laptop tray (spring loaded)</td>
			<td style="width:287px;">National Products, INC.</td>
			<td style="width:135px;">RAM-234-3&#160;</td>
			<td>RAM Tough-Tray&#8482;. Can accommodate 10 to 16 inch wide laptops.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">USB splitter</td>
			<td style="width:287px;">Connectland Technology Limited</td>
			<td style="width:135px;">3401167</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:18px;width:368px;">USB Data Acquisition Cards (8 analog input, 12 digital I/O)</td>
			<td style="width:287px;">National Instruments</td>
			<td style="width:135px;">NI USB-6008</td>
			<td>12-Bit, 10 kS/s Low-Cost Multifunction DAQ</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:368px;">USB Data Acquisition Cards (16 analog input, 32 digital I/O)</td>
			<td style="width:287px;">National Instruments</td>
			<td style="width:135px;">NI USB-6216</td>
			<td>16-Bit, 400 kS/s Isolated M Series MIO DAQ, Bus-Powered</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">Control/acquisition Software</td>
			<td style="width:287px;">National Instruments</td>
			<td style="width:135px;">LabVIEW 2009</td>
			<td>Custom coded National Instruments (NI) LabVIEW&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:22px;width:368px;">3D Solid Modeling Software</td>
			<td style="width:287px;">Dassault Syst&#232;mes SolidWorks Corp.</td>
			<td style="width:135px;">SolidWorks 2011</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">2D Modeling Software</td>
			<td style="width:287px;">AUTODESK</td>
			<td style="width:135px;">AutoCAD LT 2008</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Vertical equipment rack</td>
			<td style="width:287px;">(NASA provided)</td>
			<td style="width:135px;">N/A</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:21px;width:368px;">Solid aluminum optical breadboard</td>
			<td style="width:287px;">Thorlabs</td>
			<td style="width:135px;">MB2424</td>
			<td>24&#34; x 24&#34; x 1/2&#34;, 1/4&#34;-20 Taps; available direct from Thorlabs</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">Industrial grade steel and hardener</td>
			<td style="width:287px;">The J-B Weld Company</td>
			<td style="width:135px;"></td>
			<td>J-B Weld Steel Reinforced Epoxy Glue</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">Micro-hematocrit capillary&#160;</td>
			<td style="width:287px;">Fisher Scientific</td>
			<td style="width:135px;">22-362-574</td>
			<td>inner diamter 1.1 to 1.2 mm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">1 mL syringes</td>
			<td style="width:287px;">Henke-Sass, Wolf</td>
			<td>4010.200V0</td>
			<td>NORM-JECT&#174;; supplier: Grainger, Inc.</td>
		</tr>
		<tr height="80">
			<td height="80" style="height:81px;width:368px;">Human red blood cells</td>
			<td style="width:287px;">Innovative Research</td>
			<td>IPLA-WB3</td>
			<td style="width:1143px;">Tested and found negative by supplier for: HBsAg, HCV, HIV-1, HIV-2, HIV-1Ag or HIV 1-NAT, ALT, and syphilis by FDA-Approved Methods.&#160; Because no test methods can guarantee with 100% certainty the absence of an infectious agent, human derived products should be handled as suggested in the U.S. Department of Health and Human Services Manual on BIOSAFETY IN MICROBIOLOGICAL AND BIOMEDICAL LABORATORIES, FOR POTENTIALLY INFECTIOUS HUMAN SERUM OR BLOOD SPECIMENS</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Phosphate buffered saline concentrate</td>
			<td>P5493</td>
			<td style="width:135px;">SIGMA</td>
			<td>10x; diluted to 1x</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Tween</td>
			<td>P9416</td>
			<td style="width:135px;">SIGMA</td>
			<td>TWEEN&#174; 20</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Centrifuge</td>
			<td style="width:287px;">LW Scientific</td>
			<td style="width:135px;">STRAIGHT8-5K</td>
			<td>Swing-Out 8-place Centrifuge.&#160; Available through authorized dealers.&#160; Other centrifuges available direct from LW Scientific.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">HD video recorder</td>
			<td style="width:287px;">Sony</td>
			<td style="width:135px;">MHS-CM5</td>
			<td></td>
		</tr>
		<tr height="52">
			<td height="52" style="height:53px;width:368px;">Orange fluorescent nucleic acid stain</td>
			<td style="width:287px;">Invitrogen</td>
			<td>S-11364</td>
			<td style="width:1143px;">SYTO&#174; 83 Orange Fluorescent Nucleic Acid Stain.&#160; Stored in DMSO solvent. Always wear reccommended Personal Protective Equipment. No special handling 
			advice required.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:368px;">Fluorescent counting beads</td>
			<td style="width:287px;">Invitrogen</td>
			<td>MP 36950</td>
			<td>CountBright&#8482; Absolute Counting Beads.&#160; Always wear reccommended Personal Protective Equipment. No special handling advice required.</td>
		</tr>
	</tbody>
</table>

reduced-gravity environment hardware demonstrations of a prototype miniaturized flow cytometer and companion microfluidic mixing technology

Until recently, astronaut blood samples were collected in-flight, transported to earth on the Space Shuttle, and analyzed in terrestrial laboratories. If humans are to travel beyond low Earth orbit, a transition towards space-ready, point-of-care (POC) testing is required. Such testing needs to be comprehensive, easy to perform in a reduced-gravity environment, and unaffected by the stresses of launch and spaceflight. Countless POC devices have been developed to mimic laboratory scale counterparts, but most have narrow applications and few have demonstrable use in an in-flight, reduced-gravity environment. In fact, demonstrations of biomedical diagnostics in reduced gravity are limited altogether, making component choice and certain logistical challenges difficult to approach when seeking to test new technology. To help fill the void, we are presenting a modular method for the construction and operation of a prototype blood diagnostic device and its associated parabolic flight test rig that meet the standards for flight-testing onboard a parabolic flight, reduced-gravity aircraft. The method first focuses on rig assembly for in-flight, reduced-gravity testing of a flow cytometer and a companion microfluidic mixing chip. Components are adaptable to other designs and some custom components, such as a microvolume sample loader and the micromixer may be of particular interest. The method then shifts focus to flight preparation, by offering guidelines and suggestions to prepare for a successful flight test with regard to user training, development of a standard operating procedure (SOP), and other issues. Finally, in-flight experimental procedures specific to our demonstrations are described.

Representative results for the micromixer demonstration appear in Figure 7, as viewed by the CCD camera fitted to the stereomicroscope. Mixing can be visually assessed at any point along the spiral, as well as in the Exit channel for experiments involving two sets of fluids: blood/saline and blue/yellow dye. Quantitative analysis of the two-dimensional images can include determination of shade uniformity across the channel width in different regions, as shown in other publications 38-40. See <...

Watch this Scientific Journal Video about Reduced-gravity Environment Hardware Demonstrations of a Prototype Miniaturized Flow Cytometer and Companion Microfluidic Mixing Technology at JoVE.com

Reduced-gravity Environment Hardware Demonstrations of a Prototype Miniaturized Flow Cytometer and Companion Microfluidic Mixing Technology

Spaceflight blood diagnostics need innovation. Few demonstrations have been published illustrating in-flight, reduced-gravity health diagnostic technology. Here we present a method for construction and operation of a parabolic flight test rig for a prototype point-of-care flow-cytometry design, with components and preparation strategies adaptable to other setups.

Until recently, astronaut blood samples were collected in-flight, transported to earth on the Space Shuttle, and analyzed in terrestrial laboratories. If ...

reduced-gravity-environment-hardware-demonstrations-prototype

Research

JoVE Journal

Biology

13.6K Views.  DNA Medicine Institute. Spaceflight blood diagnostics need innovation. Few demonstrations have been published illustrating in-flight, reduced-gravity health diagnostic technology. Here we present a method for construction and operation of a parabolic flight test rig for a prototype point-of-care flow-cytometry design, with components and preparation strategies adaptable to other setups.

Video: Reduced-gravity Environment Hardware Demonstrations of a Prototype Miniaturized Flow Cytometer and Companion Microfluidic Mixing Technology

A Microfluidic Device with Groove Patterns for Studying Cellular Behavior

We describe a microfluidic device with microgrooved patterns for studying cellular behavior. This microfluidic platform consists of a top fluidic channel and a bottom microgrooved substrate. To fabricate the microgrooved channels, a top poly(dimethylsiloxane) (PDMS) mold containing the impression of the microfluidic channels was aligned and bonded to a microgrooved substrate. Using this device, mouse fibroblast cells were immobilized and patterned within microgrooved substrates (25, 50, 75, and 100 &mu;m wide). To study apoptosis in a microfluidic device, media containing hydrogen peroxide, Annexin V, and propidium iodide was perfused into the fluidic channel for 2 hours. We found that cells exposed to the oxidative stress became apoptotic. These apoptotic cells were confirmed by Annexin V that bound to phosphatidylserine at the outer leaflet of the plasma membrane during the apoptosis process. Using this microfluidic device with microgrooved patterns, the apoptosis process was observed in real-time and analyzed by using an inverted microscope containing an incubation chamber (37&deg;C, 5% CO2). Therefore, this microfluidic device incorporated with microgrooved substrates could be useful for studying the cellular behavior and performing high-throughput drug screening.

We describe a protocol for the fabrication of microfluidic devices that can enable cell capture and culture. In this approach patterned microstructures such as grooves within microfluidic channels are used to create low shear stress regions within which cell can dock.

We describe a microfluidic device with microgrooved patterns for studying cellular behavior.  This microfluidic platform consists of a top fluidic channel ...

A Gradient-generating Microfluidic Device for Cell Biology

 The fabrication and operation of a gradient-generating microfluidic device for studying cellular behavior is described.  A microfluidic platform is an enabling experimental tool, because it can precisely manipulate fluid flows, enable high-throughput experiments, and generate stable soluble concentration gradients.  Compared to conventional gradient generators, poly(dimethylsiloxane) (PDMS)-based  microfluidic devices can generate stable concentration gradients of growth factors with well-defined profiles.  Here, we developed simple gradient-generating microfluidic devices with three separate inlets.  Three microchannels combined into one microchannel to generate concentration gradients.  The stability and shape of growth factor gradients were confirmed by fluorescein isothyiocyanate (FITC)-dextran with a molecular weight similar to epidermal growth factor (EGF).  Using this microfluidic device, we demonstrated that fibroblasts exposed to concentration gradients of EGF migrated toward higher concentrations.  The directional orientation of cell migration and motility of migrating cells were quantitatively assessed by cell tracking analysis.  Thus, this gradient-generating microfluidic device might be useful for studying and analyzing the behavior of migrating cells.

We describe a protocol for the microfabrication of the gradient-generating microfluidic device that can generate spatial and temporal gradients in well-defined microenvironment. In this approach, the gradient-generating microfluidic device can be used to study directed cell migration, embryogenesis, wound healing, and cancer metastasis.

 The fabrication and operation of a gradient-generating microfluidic device for studying cellular behavior is described.  A microfluidic platform is an ...

CD4+ T-Lymphocyte Capture Using a Disposable Microfluidic Chip for HIV

A Multi-compartment CNS Neuron-glia Co-culture Microfluidic Platform

We present a novel multi-compartment neuron co-culture microsystem platform for in vitro CNS axon-glia interaction research, capable of conducting up to six independent experiments in parallel for higher-throughput. We developed a new fabrication method to create microfluidic devices having both micro and macro scale structures within the same device through a single soft-lithography process, enabling mass fabrication with good repeatability.
The multi-compartment microfluidic co-culture platform is composed of one soma compartment for neurons and six axon/glia compartments for oligodendrocytes (OLs). The soma compartment and axon/glia compartments are connected by arrays of axon-guiding microchannels that function as physical barriers to confine neuronal soma in the soma compartment, while allowing axons to grow into axon/glia compartments. OLs loaded into axon/glia compartments can interact only with axons but not with neuronal soma or dendrites, enabling localized axon-glia interaction studies. The microchannels also enabled fluidic isolation between compartments, allowing six independent experiments to be conducted on a single device for higher throughput.
Soft-lithography using poly(dimethylsiloxane) (PDMS) is a commonly used technique in biomedical microdevices. Reservoirs on these devices are commonly defined by manual punching. Although simple, poor alignment and time consuming nature of the process makes this process not suitable when large numbers of reservoirs have to be repeatedly created. The newly developed method did not require manual punching of reservoirs, overcoming such limitations. First, seven reservoirs (depth: 3.5 mm) were made on a poly(methyl methacrylate) (PMMA) block using a micro-milling machine. Then, arrays of ridge microstructures, fabricated on a glass substrate, were hot-embossed against the PMMA block to define microchannels that connect the soma and axon/glia compartments. This process resulted in macro-scale reservoirs (3.5 mm) and micro-scale channels (2.5 &mu;m) to coincide within a single PMMA master. A PDMS replica that served as a mold master was obtained using soft-lithography and the final PDMS device was replicated from this master.
Primary neurons from E16-18 rats were loaded to the soma compartment and cultured for two weeks. After one week of cell culture, axons crossed microchannels and formed axonal only network layer inside axon/glia compartments. Axons grew uniformly throughout six axon/glia compartments and OLs from P1-2 rats were added to axon/glia compartments at 14 days in vitro for co-culture.

We developed a novel multi-compartment neuron co-culture microsystem platform for in vitro CNS axon-glia interaction research. The platform is capable of conducting up to six independent experiments in parallel and was fabricated using a newly developed macro/micro hybrid fabrication method.

We present a novel multi-compartment neuron co-culture microsystem platform for in vitro CNS axon-glia interaction research, capable of conducting up to ...

The Microfluidic Probe: Operation and Use for Localized Surface Processing

Microfluidic devices allow assays to be performed using minute amounts of sample and have recently been used to control the microenvironment of cells. Microfluidics is commonly associated with closed microchannels which limit their use to samples that can be introduced, and cultured in the case of cells, within a confined volume. On the other hand, micropipetting system have been used to locally perfuse cells and surfaces, notably using push-pull setups where one pipette acts as source and the other one as sink, but the confinement of the flow is difficult in three dimensions. Furthermore, pipettes are fragile and difficult to position and hence are used in static configuration only. 
The microfluidic probe (MFP) circumvents the constraints imposed by the construction of closed microfluidic channels and instead of enclosing the sample into the microfluidic system, the microfluidic flow can be directly delivered onto the sample, and scanned across the sample, using the MFP. . The injection and aspiration openings are located within a few tens of micrometers of one another so that a microjet injected into the gap is confined by the hydrodynamic forces of the surrounding liquid and entirely aspirated back into the other opening. The microjet can be flushed across the substrate surface and provides a precise tool for localized deposition/delivery of reagents which can be used over large areas by scanning the probe across the surface. 
In this video we present the microfluidic probe1 (MFP). We explain in detail how to assemble the MFP, mount it atop an inverted microscope, and align it relative to the substrate surface, and finally show how to use it to process a substrate surface immersed in a buffer.

In this video we present the microfluidic probe1 (MFP). We explain in detail how to assemble the MFP, mount it atop an inverted microscope, and align it relative to the substrate surface, and finally show how to use it to process a substrate surface immersed in a buffer solution.

Microfluidic devices allow assays to be performed using minute amounts of sample and have recently been used to control the microenvironment of cells. ...

Platelet Adhesion and Aggregation Under Flow using Microfluidic Flow Cells

Platelet aggregation occurs in response to vascular injury where the extracellular matrix below the endothelium has been exposed. The platelet adhesion cascade takes place in the presence of shear flow, a factor not accounted for in conventional (static) well-plate assays. This article reports on a platelet-aggregation assay utilizing a microfluidic well-plate format to emulate physiological shear flow conditions. Extracellular proteins, collagen I or von Willebrand factor are deposited within the microfluidic channel using active perfusion with a pneumatic pump. The matrix proteins are then washed with buffer and blocked to prepare the microfluidic channel for platelet interactions. Whole blood labeled with fluorescent dye is perfused through the channel at various flow rates in order to achieve platelet activation and aggregation. Inhibitors of platelet aggregation can be added prior to the flow cell experiment to generate IC50 dose response data.

The platelet adhesion cascade takes place in the presence of shear flow, a factor not accounted for in conventional (static) well-plate assays. This article reports on a platelet-aggregation assay utilizing a microfluidic well-plate format to emulate physiological shear flow conditions.

Platelet aggregation occurs in response to vascular injury where the extracellular matrix below the endothelium has been exposed. The platelet adhesion ...

Microfluidic Co-culture of Epithelial Cells and Bacteria for Investigating Soluble Signal-mediated Interactions

The human gastrointestinal (GI) tract is a unique environment in which intestinal epithelial cells and non-pathogenic (commensal) bacteria coexist. It has been proposed that the microenvironment that the pathogen encounters in the commensal layer is important in determining the extent of colonization. Current culture methods for investigating pathogen colonization are not well suited for investigating this hypothesis as they do not enable co-culture of bacteria and epithelial cells in a manner that mimics the GI tract microenvironment. Here we describe a microfluidic co-culture model that enables independent culture of eukaryotic cells and bacteria, and testing the effect of the commensal microenvironment on pathogen colonization. The co-culture model is demonstrated by developing a commensal Escherichia coli biofilm among HeLa cells, followed by introduction of enterohemorrhagic E. coli (EHEC) into the commensal island, in a sequence that mimics the sequence of events in GI tract infection.

This protocol describes a microfluidic co-culture model for simultaneous and localized culture of epithelial cells and bacteria. This model can be used for investigating the role of different soluble molecular signals on pathogenesis as well as screen the effectiveness of putative probiotic bacterial strains.

The human gastrointestinal (GI) tract is a unique environment in which intestinal epithelial cells and non-pathogenic (commensal) bacteria coexist. It has ...

Quantifying Mixing using Magnetic Resonance Imaging

Mixing is a unit operation that combines two or more components into a homogeneous mixture. This work involves mixing two viscous liquid streams using an in-line static mixer. The mixer is a split-and-recombine design that employs shear and extensional flow to increase the interfacial contact between the components. A prototype split-and-recombine (SAR) mixer was constructed by aligning a series of thin laser-cut Poly (methyl methacrylate) (PMMA) plates held in place in a PVC pipe. Mixing in this device is illustrated in the photograph in Fig. 1. Red dye was added to a portion of the test fluid and used as the minor component being mixed into the major (undyed) component. At the inlet of the mixer, the injected layer of tracer fluid is split into two layers as it flows through the mixing section. On each subsequent mixing section, the number of horizontal layers is duplicated. Ultimately, the single stream of dye is uniformly dispersed throughout the cross section of the device.
 Using a non-Newtonian test fluid of 0.2% Carbopol and a doped tracer fluid of similar composition, mixing in the unit is visualized using magnetic resonance imaging (MRI). MRI is a very powerful experimental probe of molecular chemical and physical environment as well as sample structure on the length scales from microns to centimeters. This sensitivity has resulted in broad application of these techniques to characterize physical, chemical and/or biological properties of materials ranging from humans to foods to porous media 1, 2. The equipment and conditions used here are suitable for imaging liquids containing substantial amounts of NMR mobile 1H such as ordinary water and organic liquids including oils. Traditionally MRI has utilized super conducting magnets which are not suitable for industrial environments and not portable within a laboratory (Fig. 2). Recent advances in magnet technology have permitted the construction of large volume industrially compatible magnets suitable for imaging process flows. Here, MRI provides spatially resolved component concentrations at different axial locations during the mixing process. This work documents real-time mixing of highly viscous fluids via distributive mixing with an application to personal care products.

Magnetic resonance imaging (MRI) provides a powerful tool to evaluate the effectiveness of process equipment during operation. We discuss the use of MRI to visualize mixing in a static mixer. The application is relevant to personal care products, but can be applied to a broad range of food, chemical, biomass and biological fluids.

Mixing is a unit operation that combines two or more components into a homogeneous mixture.  This work involves mixing two viscous liquid streams using an ...

Chromosomics: Detection of Numerical and Structural Alterations in All 24 Human Chromosomes Simultaneously Using a Novel OctoChrome FISH Assay

Fluorescence in situ hybridization (FISH) is a technique that allows specific DNA sequences to be detected on metaphase or interphase chromosomes in cell nuclei1. The technique uses DNA probes with unique sequences that hybridize to whole chromosomes or specific chromosomal regions, and serves as a powerful adjunct to classic cytogenetics. For instance, many earlier studies reported the frequent detection of increased chromosome aberrations in leukemia patients related with benzene exposure, benzene-poisoning patients, and healthy workers exposed to benzene, using classic cytogenetic analysis2. Using FISH, leukemia-specific chromosomal alterations have been observed to be elevated in apparently healthy workers exposed to benzene3-6, indicating the critical roles of cytogentic changes in benzene-induced leukemogenesis. 
Generally, a single FISH assay examines only one or a few whole chromosomes or specific loci per slide, so multiple hybridizations need to be conducted on multiple slides to cover all of the human chromosomes. Spectral karyotyping (SKY) allows visualization of the whole genome simultaneously, but the requirement for special software and equipment limits its application7. Here, we describe a novel FISH assay, OctoChrome-FISH, which can be applied for Chromosomics, which we define here as the simultaneous analysis of all 24 human chromosomes on one slide in human studies, such as chromosome-wide aneuploidy study (CWAS)8. The basis of the method, marketed by Cytocell as the Chromoprobe Multiprobe System, is an OctoChrome device that is divided into 8 squares, each of which carries three different whole chromosome painting probes (Figure 1). Each of the three probes is directly labeled with a different colored fluorophore, green (FITC), red (Texas Red), and blue (Coumarin). The arrangement of chromosome combinations on the OctoChrome device has been designed to facilitate the identification of the non-random structural chromosome alterations (translocations) found in the most common leukemias and lymphomas, for instance t(9;22), t(15;17), t(8;21), t(14;18)9. Moreover, numerical changes (aneuploidy) in chromosomes can be detected concurrently. The corresponding template slide is also divided into 8 squares onto which metaphase spreads are bound (Figure 2), and is positioned over the OctoChrome device. The probes and target DNA are denatured at high-temperature and hybridized in a humid chamber, and then all 24 human chromosomes can be visualized simultaneously. 
OctoChrome FISH is a promising technique for the clinical diagnosis of leukemia and lymphoma and for detection of aneuploidies in all chromosomes. We have applied this new Chromosomic approach in a CWAS study of benzene-exposed Chinese workers8,10.

A novel fluorescence in situ hybridization (FISH) method that simultaneously examines both numerical and structural chromosome alterations, particularly the specific chromosomal translocations associated with leukemia and lymphoma, of all 24 human chromosomes on a single device in one hybridization, is described.

Fluorescence in situ hybridization (FISH) is a technique that allows specific DNA sequences to be detected on metaphase or interphase chromosomes in cell ...

Assessment of GFP Expression and Viability Using the Tali Image-Based Cytometer

Single-cell and population information are commonly obtained either by flow cytometry or fluorescence microscopy. However, these two methods provide different information. Flow cytometry gives quantitative multi-parametric information about physical characteristics and staining or expression, but doesn't allow for visualization. Stand-alone fluorescence microscopy provides visual data, but doesn't allow for straightforward quantitative measurements1.
Image-based cytometry bridges the gap between these two methods, enabling the quick visualization and simultaneous quantitative analysis of thousands of cells in heterogeneous populations2. Here, we present a method for performing cell viability and green fluorescent protein (GFP) expression assays using the Tali Image-Based Cytometer3. The Tali instrument is a 3-channel (bright field, green fluorescence, red fluorescence) benchtop assay platform that offers several advantages over flow cytometry and fluorescence microscopy. The Tali cytometer is less expensive, takes up less bench space, requires less maintenance, and the work flow has been simplified so that the operation and analysis is much simpler and quicker. The Tali cytometer is capable of performing a range of suspension cell-based assays, including GFP and red fluorescent protein (RFP) expression, apoptosis4-6 and cell viability analysis with propidium iodide (PI)7-11.
Here, we demonstrate the use of the Tali instrument in performing a cell viability assay in cells expressing GFP. GFP-transduced cells are stained using the Tali Viability Kit - Dead Cell Red. The cells are then pipetted into a Tali Cellular Analysis Slide and loaded into the cytometer. Bright field, red fluorescence and green fluorescence images are captured and analyzed using assay specific algorithms. Histograms are then generated to display cell size, PI fluorescence intensity, and GFP fluorescence intensity. These parameters can then be thresholded to home in on a specific cell population.
A side-by side comparison of the Tali Image-Based Cytometer and traditional flow cytometry demonstrates that the two methods provide comparable data regarding cell viability and protein expression. However, the Tali instrument provides additional visual information about the cell population that cannot be obtained using a flow cytometer.

This protocol describes how to perform cell viability and fluorescence expression assays using the Tali Image-Based Cytometer.

Single-cell and population information are commonly obtained either by flow cytometry or fluorescence microscopy. However, these two methods provide ...