In order to best study the effects of microgravity on the human body, on-site testing is preferred. By performing chemical analyses on-site, results will be rapid, and samples will not need to be stored for the duration of the mission for later testing on earth. Due to severe storage limitations and power requirements for spaceflight, a portable system needs to be developed with minimal footprint and power consumption. Microfluidic devices provide an ideal platform for this application due to small reaction volumes, reduced reagent consumption, and the ability to integrate multiple preparative and analytical processes into a single device [Easley, et. al. PNAS, 2006, 19272-19277].

This work focuses on solid phase extraction (SPE), a preparative technique often utilized for purification of select analytes from biological fluids. In addition, it removes interfering compounds and concentrates the analyte of interest prior to the analytical process. Conventional SPE in a cartridge format is not suitable for spaceflight due to the need for vacuum required to drive fluid manipulation, interfacing, and collection. The microchip SPE presented here uses channels etched into a glass substrate to provide the column to house particles (derivatized with the appropriate chemistry) for extraction. Driven manually by a syringe, a wide range of solid phases are available for a variety of chemistries, so the device can be adapted for different purposes. A commercially-available hydrophilic-lipophilic copolymer was used to extract oxidative stress markers spiked into saliva showing recoveries up to 100% and concentration enhancements up to 80-fold.

This technique was also applied to other drugs of interest for spaceflight, including promethazine, pseudoephedrine, ciprofloxacin, and acetaminophen. Future integration with separation and analyte detection will make this a powerful tool for studying the effects of microgravity on oxidative stress and drug metabolism during space missions.

ESA has initiated the BMTC (Biotechnology Mammalian Tissue Culture Facility) program in order to:

Although many bioreactors have been described, very few can apply the specific mechanical forces that are needed to stimulate or maintain tissue fitness and very few can also measure the mechanical properties of the tissue. The mechanical properties of the tissue, such as stiffness, elasticity, breaking strength etc is for several tissues such as bone, cartilage, tendon, muscle, the most significant property. Other tissues such as the lungs, hair , blood vessels etc also have specific mechanical properties necessary for their proper function, while organs such as the brain, spleen, glands etc do not seem to need specific mechanical properties as such. Hence many organs and tissues of the body are defined by their mechanical properties.

Over the last 10 years the Zetos group has been designing and working with a bone bioreactor called Zetos (1). This device is used to investigate the role of mechanical forces on bone and several investigations have been published that show that in vivo -like responses to mechanical loading are reproduced (2,3,4,5) , justifying its use as a model system for many bone related investigations. One of the many investigations was into the role of high frequency. Any desired waveform can be applied such as those typical of walking, running and jumping. An in built FFT filter was used to cut frequencies lower than 30Hz and only apply frequencies above 30Hz (controls were the normal signal and the low frequency signal). The results showed that the high frequency components alone can significantly stimulate bone formation. These results were the basis of the forthcoming Freqbone experiment on a Foton flight last year, coordinated by the Leuven group.

However if it is desired to apply physiological forces to other tissues than bone, such as cartilage, tendon and muscle, these require much higher expansions of the actuator (of up to 1600µm) and also apply motions other than compression. Stretching can also be required.

Hence a new mechanical design using different actuators and a new electronics design using real time positive feedback and new sensors has been carried out which results in a radically different concept of the bioreactor. As for the original bone Zetos, the devices are designed to also gain precise information on several mechanical properties, stiffness, visco elasticity etc.

Cartilage is one of the major targets for tissue engineering. Presently little is known precisely about the mechanical properties of cartilage. It is known that the stiffness is dependant on the frequency of loading . The visco-elastic properties are also very complex. Hence a extremely fast (0.4MHz and upwards) feedback of the position sensor and force sensor are required to control the loading and the mechanical properties sensing. The Zetos for cartilage, Zetos C or Chondros is being implemented for the BMTC project by CytoScience SA Switzerland.

This project is supported by the European Space Agency Microgravity Applications programme, several awards of the AO foundation Davos and The Robert Mathys Foundation. David Jones is a currently also a director of CytoScience SA of Fontaines Switzerland.

References:- D.B. Jones, et al European Cells and Materials 5: 48-60 2003 Murray C.H. Clarke, .et al JCB. 160:577-587 2003 Davies CM,. Eur Cell Mater et al11 57-75. 2006 V. Mann, J et al Musculoskelet Neuronal Interact 2006; 6(4):408-417 Valentin David . Endocrinology. 2007 May;148(5

Dymanic fluorescence imaging is a very powerful tool for biology. Rapid changes (less than 1 sec) in intraclelular signalling ions such as calcium, changes in membrane potential, the activity of many signallingmolecules such as phospholipase A2 and nitric oxide can be easily followed in real time. The challenge was to incorporate the necessary equipment into a size that could fit into a research space vehicle such as the Zero G plane, the Texus rocket, the Foton capsule and for the ISS. The soliution to this was the invention of the LED fluorescence microscope and using the great advances in elctronics miniaturisation. The use of LEDS also makes the fluorescence microscope extremely useful on Earth too especially in the field. Versions are being made for schools, disease detection int he developing world and for the military. As many as 9 different wavelengths can be used including the most common one at 490nm.

Refs Jones et al LED Fluorescence Microscopy Made for Space for Use on Earth Vol. 40/2 Proceedings RMS June 2005
Jones et al McArthur revisited: fluorescence microscopes for field diagnosticsTrends in Paristology 23: 468 2007
Jones et al. Dynamic Fluorescent Imaging and Photometry of Cells in Microgravity Proc. Roy Microscop. Soc. 38:67-73, 2003

Dymanic fluorescence imaging is a very powerful tool for biology. Rapid changes (less than 1 sec) in intraclelular signalling ions such as calcium, changes in membrane potential, the activity of many signallingmolecules such as phospholipase A2 and nitric oxide can be easily followed in real time. The challenge was to incorporate the necessary equipment into a size that could fit into a research space vehicle such as the Zero G plane, the Texus rocket, the Foton capsule and for the ISS. The soliution to this was the invention of the LED fluorescence microscope and using the great advances in elctronics miniaturisation. The use of LEDS also makes the fluorescence microscope extremely useful on Earth too especially in the field. Versions are being made for schools, disease detection int he developing world and for the military. As many as 9 different wavelengths can be used including the most common one at 490nm.
Refs Jones et al LED Fluorescence Microscopy Made for Space for Use on Earth Vol. 40/2 Proceedings RMS June 2005
Jones et al McArthur revisited: fluorescence microscopes for field diagnosticsTrends in Paristology 23: 468 2007
Jones et al. Dynamic Fluorescent Imaging and Photometry of Cells in Microgravity Proc. Roy Microscop. Soc. 38:67-73, 2003

The COLUMBUS Module was successfully launched with the Space Shuttle Atlantis on Feb. 7th, 2008. Following the mounting of the COLUMBUS Module to the ISS, the first commissioning of the payload facilities inside COLUMBUS was also performed successfully.

One payload inside COLUMBUS is the BIOLAB facility. BIOLAB is a multi-user biology laboratory which allows experiments on cells, tissues, small plants and small animals. Heartpiece of the BIOLAB is the incubator with the life support system which provides defined environmental parameters; the two rotors inside the incubator provide different g levels up to 2g and video observation. For manual operations by the astronaut a bioglovebox is available. The biological and biomedical samples are accommodated in experiment-specific containers supplied by the life support system (oxygen, carbon dioxide, nitrogen and ethylene removal). Automatic on-board analysis is possible by means of a microscope and a spectrophotometer. A small robotic arm is capable of transfering e.g. liquids between incubator and automated cooler and a.m. analysis instruments. Moreover, BIOLAB allows an interactive mode of operation between astronaut in space and ground crew by means of telescience and teleoperations. This capability was widely used already for the first utilisation of BIOLAB for the first experiment on plants.

In support of the scientists, the German Aerospace Center (MUSC) is interfacing with the astronauts on orbit and partners of the ISS ground segment, e.g. the Facility Support Center BIOTESC and the COLUMBUS Control Center COL-CC.

The experiences gained so far in on-orbit operations and experimenting with BIOLAB will be explained and illustrated to better understand how to work and perform experiments in the BIOLAB facility now as a permanent part of the ISS.

The Russian FOTON-M3 mission, a satellite for mid-length experiments in space and recovery afterwards, included a closed artificial ecosystem (OMEGAHAB) with the photosynthetic flagellate Euglena gracilis as oxygen producer and larvae of Oreochromis mossambicus, a tilapia species, as consumer. During the 12-day orbital flight the algae were observed 10 minutes per day by means of a miniaturized microscope to analyse their swimming behaviur. The fishes were also filmed to monitor their development and movement. Parameters like water temperature, oxygen concentration, residual acceleration and status of electric components were monitored by the electronics, which also controlled the illumination of the algae for photosynthetic oxygen production, the feeding of the larvae by an integrated feeder, the temperature management, the filming of the organisms and the data and video handling with an external storage facility. An identical experiment was carried out as ground control. A data downlink provided the measured temperature values of the space experiment every day to readjust the temperature of the ground reference in order to eliminate the influence of the different temperature onto the velocity of the development of the fishes. After landing of the descent vehicle, 11 of 26 larvae were retrieved from the bioreactor. They showed distinct differences in their developmental stage compared to the ground reference animals.

The algae proofed their ability to serve as oxygen producers in a small-scale life support system for aquatic organisms. Currently effects of cosmic radiation on the DNA are being analysed. The system worked very well and confirmed the design in principle. OMEGAHAB was the most successful German experiment of that kind as yet.

Currently, experiments are performed to analyze the photosynthetic performance of Euglena gracilis under micro- and hypergravity in greater detail. In an upcoming mission the so called fast kinetics of photosynthesis will be analyzed by means of pulse amplitude modulation fluorescence measurement (PAM). In addition, light quality and quantity with respect to photosynthetic performance will be tested.