Chemical Sensors & Biosensors

This Chemistry Department Facility is located in 103 Crosley Tower. Contact Dr. Necati Kaval for information and scheduling. (513) 556-9201, kavaln@ucmail.uc.edu.

  • Fourier Transform Infrared Spectrophotometer (FTIR)
    Nicolet 6700 FTIR Spectrophotometer is used to collect infra-red spectra of organic and inorganic materials in the 4000 cm-1 and 400 cm-1 spectral range.  Instrument is frequently used with a Smart Orbit diamond ATR module which requires minimum sample preparation time. Other modules are also available for transmission, specular reflection and diffuse reflection measurements. Samples can be in solid or liquid form.
  • Fourier Transform Infrared Microscope (FTIR-Microscope)
    FTIR microscope is often used for samples too small for a conventional FTIR spectrophotometer, such as microscopic materials and fibers. Facility maintains a Nicolet Continuum model FTIR microscope, which is coupled to Nicolet 6700 FTIR instrument. FTIR microscope requires liquid nitrogen cooling of its detector. Typical spectral range is from 4000 cm-1 to 650 cm-1. FTIR spectra can be collected both in reflection and transmission modes.
  • Raman Microscope
    Renishaw InVia Raman microscope is used to collect Raman spectra of micro and macro size materials, both in solid and liquid forms. Raman microscope offers a wide range of laser lines at 442 nm, 457 nm, 488 nm, 514 nm, 633 nm and 785 nm. Microscope stage and sample area are completely enclosed with interlock for laser safety.  Motorized microscope stage with the remote console allows manipulation of the sample remotely and collection of Raman surface mapping data. A portable sample heating and cooling stage which provides temperature control from 10oC and 90oC is available.
  • Environmental Scanning Electron Microscope (ESEM)
    The FEI XL30 ESEM is capable of high resolution imaging.  Instrument operates under high vacuum SEM mode for electrically conductive samples as well as low vacuum ESEM mode for non-conductive samples, such as biological specimens. An integrated Energy Dispersive X-ray Spectrometer (EDS) from EDAX allows elemental analysis and mapping. A solid state back-scatter electron detector is also available for elemental contrast imaging.
  • Digital Light Microscope
    Keyence VHX-1000 is a computer-controlled digital microscope with a large display for viewing the images. Users can capture still images, time-lapse images, and perform video recording at magnifications ranging from 20x to 1000x.  Microscope software allows image improvements and measurements of various geometric dimensions. 3D image capturing and visualization are also possible for many types of samples. A portable sample heating and cooling stage which allows temperature control from 10oC to 90oC is available.
  • Scanning Probe Microscope
    Facility consists of a Multimode Scanning Probe Microscope from Bruker (Veeco) operated with a Nanoscope III controller. This instrument can perform Atomic Force Microscopy (AFM-contact mode and tapping mode), Scanning Tunneling Microscopy (STM), Electrical Field Microscopy (EFM), Magnetic Field Microscopy (MFM).
  • Variable Angle Spectroscopic Ellipsometer (VASE)
    Determination of the thicknesses and optical constants (n-refractive index, k-extinction coefficient, etc.) of thin films can be obtained using the spectroscopic ellipsometer (J.A. Woollam Inc.). Elippsometric data can be collected at various angles, and wavelengths between 240 nm and 1100 nm. The practical range of thickness for non-absorbing films that can be accurately measured is approximately a few nanometers to several micrometers. This range is reduced for optically absorbing films -semiconductors, metals, etc.
  • UV/Vis Spectrophotometer
    The Varian Cary 50 Bio UV/Vis absorbance spectrophotometer can be used to collect absorbance and transmission spectra of both liquid and solid samples. The intense xenon flash lamp allows the use of micro cells. Sample volume can be as low as 100 mL to a few mLs. The xenon lamp flashes only when acquiring a data point, so photosensitive samples are not exposed to light when idle. The instrument can measure samples up to 3 Abs units between 200 nm and 900 nm. With the single cell Peltier accessory users can control the sample temperature between 10oC and 90oC.
  • Fluorescence Spectrophotometer
    The Varian Cary Eclipse fluorescence spectrophotometer offers high performance measurements in fluorescence, phosphorescence or chemo/bio luminescence modes. The light source is a xenon flash lamp which provides excellent sensitivity. Besides the conventional single cell holder, the instrument has a temperature controlled multi-cell holder and a variable angle solid sample holder.
  • Plate Reader
    BioTek Synergy 4 is a multi-detection microplate reader for fast and high-throughput detection. Detection modes include fluorescence intensity, luminescence, and UV-visible absorbance. Instrument is capable of both filter-based and monochromator-based detection in the UV-Visible range.  It accommodates plates from 6 wells to 1536 wells. Temperature control from 4oC to 50oC and internal plate shaking are supported.
  • Isothermal Titration Calorimeter (ITC)
    An ITC instrument measures heat evolved or absorbed due to molecular interactions in liquids. VP-ITC micro calorimeter requires approximately 1.5 mL sample for the cell and 300 uL sample for the auto syringe. Cell temperature can be controlled between 2 oC and 80 oC. Data is analyzed using an Origin-based software. The technique provides affinity constant, stoichiometry, enthalpy and entropy of molecular interactions.
  • Thermogravimetric Analysis and Differential Scanning Calorimetry (TGA/DSC)
    The facility contains a NETZSCH STA 409 PC Luxx simultaneous TGA/DSC instrument. This instrument runs in the temperature range of 25°C to ~1700°C under Argon atmosphere, and provides both TGA and DSC data simultaneously. Information pertaining to thermal stabilities, gas sorption, glass transitions and melting points of various materials can be obtained from the instrument.
  • Four-Point Probe
    Jandel, model RM2 four-point probe is dedicated to measurements of electrical resistivity of samples. The Four-Point-Probe consists of a vertically adjustable probe head mounted on a horizontal platform and a constant current source combined with a digital voltmeter. This equipment can measure the resistivity of samples such as metals, silicon wafers, conductive polymer films, etc.