We are exploring analytical chemistry which makes available what are not unable so far. We investigate chemistry of atmosphere and water environment using our original devices and latest analytical instruments. Also analytical chemistry for simple medical diagnosis, from a single drop of blood and breath air, is also our interest.
We monitored biogenic volatile organic compounds (BVOCs) and secondary produced compounds from the BVOCs. The BVOCs contribute to enhancement of oxidants. We evaluated the effect of anthropogenic (AVOCs) and BVOCs on the incrementing oxidants and showed that BVOCs contributed this more than AVOCs, especially isoprene (C5H10) is the most important BVOCs to increase oxidant concentrations. Also BVOCs produce several compounds: e.g. 70% of formaldehyde produced in the forest were produced from isoprene in the reaction with OH radical. Devices, we developed, made enable to monitor trace volatile compounds semi-continuously.
- Oxidant increment in the forest air (in Japanese)
- Formaldehyde Content of Atmospheric Aerosol Environmental Science and Technology, 48 (12), pp.6636 - 6643 (2014).
- Mobile Monitoring Along a Street Canyon and Stationary Forest Air Monitoring of Formaldehyde by Means of a Micro Gas Analysis System Journal of Environmental Monitoring, 14 (5), pp.1462 – 1472 (2012).
- On-site monitoring of formaldehyde in urban and forest atmosphere by means of micro gas analysis system (in Japanese), Bunseki，2012 (12) 685-691.
- On-site multi monitoring of isoprene and related compounds in forest air Bunseki Kagaku, 60 (6), pp.489 – 498 (2011).
Aerosols are special small particles in the atmosphere which have large specific surface area. The surface of aerosol can be an interface for absorption/desorption of volatile compounds and also can be a catalyst where several kinds of redox reactions occur. The chemistries of aerosol are not understood well, and we, chemists, have several interesting topics on cutting edges regarding the atmospheric particles including PM2.5.
- Direct Determination of Polycyclic Aromatic Hydrocabons in PM2.5 by Thermal Desorption-GC/MS and Analysis of Their Diurnal/Seasonal Variations and Field Burning in Kumamoto, Bunseki Kagaku, 64 (8), pp.571-579 (2015).
- Level, Indoor-Outdoor Relationship and Exposure Risks of Airbone Particle-Associated Perchlorate and Chlorate in Two Urban Areas in Estan Asia Chemosphere, 135, pp.31-37 (2015).
- Formaldehyde Content of Atmospheric Aerosol Environmental Science and Technology, 48 (12), pp.6636-6643 (2014).
- Investigation of daily variation of atmospheric nitrophenols by means of inline preconcentration-HPLC/MS analysis with large volume injection Bunseki Kagaku, 62 (9), pp.775-783 (2013).
Volcanic gases such as hydrogen sulfide and sulfur dioxide are one of the barometers to understand activity of volcanos. We are having long term trends and spatial variations of volcanic gases using μGAS (micro gas analysis system). Monitoring of such these gases are not only in volcano but also in Ariake Sea for estimating emission of sulfur gases from tidal flat and in pig productions for analyzing odorous reduced sulfur compounds.
- Long-term and mobile monitoring of atmospheric sulfur dioxide and hydrogen sulfide at Mt. Aso and Kumamoto city Bunseki Kagaku, 55 (2), pp.109 – 115 (2006).
- On-Site Measurement of Hydrogen Sulfide and Sulfur Dioxide Emissions from Tidal Flat Sediment of Ariake Sea, Japan. Atmospheric Environment, 39 (33), pp.6077 – 6087 (2005)./li>
- Atmospheric Methanethiol Emitted from a Pulp and Paper Plant on the Shore of Lake Baikal. Atmospheric Environment, 44, pp.2427 – 2433 (2010).
- Dynamics of Sulfur-Containing Admixtures in the Atmosphere around a Point of Source – the Baikal Pulp and Paper Plant on the Southeast Coast of Lake Baikal. Atmospheric and Oceanic Optics, 23 (1), pp.32 – 38 (2010).
- Evaluation of Single Column Trapping/Separation and Chemiluminescence Detection for Measurement of Methanethiol and Dimethyl Sulfide from Pig Production Journal of Analytical Methods in Chemistry, 2012, 489239, 7 pages doi: 10.1155/2012/489239.
- Single Column Trapping/Separation and Chemiluminescence Detection for On-Site Measurement of Methyl Mercaptan and Dimethyl Sulfide. Analytical Chemistry, 78 (17), pp.6252 – 6259 (2006).
Now in progress and details will be reported later.
- Monitoring variations of dimethyl sulfide and dimethylsulfoniopropionate in seawater and the atmosphere based on sequential vapor generation and ion molecule reaction mass spectrometry, Environmental Science: Processes & Impacts, 18 (4), pp.464-472 (2016).
- Simple Field Device for Measurement of Dimethyl Sulfide and Dimethylsulfoniopropionate in Natural Waters, Based on Vapor Generation and Chemiluminescence Detection Analytical Chemistry, 85 (9), pp.4461 - 4467 (2013).
We developed miniature gas collection devices using microchannel arranged in honeycomb pattern covered with a gas permeable hydrophobic membrane. The device made the absorbing solution layer very thin with large collection area, and this made the collection efficiency 20,000 times greater compared to the conventional impinger. So that trace level of water soluble gases can be analyzed continuously. In addition, μGAS can be operated by a small battery and mobile monitoring can be performed.
Other than the microchannel scrubber, several necessary techniques were developed for μGAS such as micro fluorescence detector, micro liquid flow sensor, micro flow control valve, micro standard gas generator.
- Development of Micro Gas Analysis System and Its Applications to Environmental Analysis Bunseki Kagaku, 63 (11), pp.873-883 (2014).
- Gas Analyzer for Continuous Monitoring of Trace Level Methanethiol by Microchannel Collection and Fluorescence Detection Analytica Chimica Acta, 841 (1), pp.1-9 (2014).
- Membrane-Based Microchannel Device for Continuous Quantitative Extraction of Dissolved Free Sulfide from Water and from Oil Analytica Chimica Acta, 741 (1), pp.38-46 (2012).
- Mobile Monitoring Along a Street Canyon and Stationary Forest Air Monitoring of Formaldehyde by Means of a Micro Gas Analysis System Journal of Environmental Monitoring, 14 (5), pp.1462-1472 (2012).
- On-Site Measurement of Trace-Level Sulfide in Natural Waters by Vapor Generation and Microchannel Collection Environmental Science and Technology, 45 (12), pp.5622-5628 (2011).
- Miniature Open Channel Scrubber for Gas Collection Talanta, 82, pp.1870–1875 (2010).
- Micro Gas Analyzer Measurement of Nitric Oxide in Breath by Direct Wet Scrubbing and Fluorescence Detection. Analytical Chemistry, 81 (16), pp.7031–7037 (2009).
- Environmental Applications: Atmospheric Trace Gas Analyses. in “Advances in Flow Injection Analysis and Related Techniques”, Comprehensive Analytical Chemistry, 53, Chapter 22, pp.639–683 (2008).
- In Situ Gas Generation for Micro Gas Analysis System. Analtica Chimica Acta, 588 (1), pp. 147 – 152 (2007).
- Miniature Liquid Flow Sensor and Feedback Control of Electroosmotic and Pneumatic Flows for a Micro Gas Analysis System. Analytical Sciences, 22 (1), pp.61 – 65 (2006).
- Micro Gas Analysis System for Measurement of Atmospheric Hydrogen Sulfide and Sulfur Dioxide. Lab-on-a-Chip, 5 (12), pp.1374 – 1379 (2005).
- Micro-Gas Analysis System μGAS Comprising a Microchannel Scrubber and a Micro-Fluorescence Detector for Measurement of Hydrogen Sulfide. Analytica Chimica Acta, 511, pp.3–10 (2004).
Device to extract analyte ions from a single drop of whole blood for instrumental analysis without centrifuging or protein removal. Analysis and diagnosis can be performed only from sampling a single drop of whole blood.
- Micro Ion Extractor for single Drop Whole Blood Analysis. Analytical Chemistry, 87 (13), pp.6483-6486 (2015).
- Miniature Device Extracts Ions from a Single Blood Drop. Chemical Engineering News (2015).