Equipment

Thanks to the 3 different light sources and the filters and analysers mounted, the BX61 is a very versatile microscope. It allows the users to perform optical observation using the following imaging modes:

• Bright field (epi or dia-illumination)
• Phase contrast (dia-illumination)
• Differential Interference Contrast (epi-illumination)
• Fluorescence observation (epi-illumination at 3 different wavelengths: UV 360-370nm; Blue 470-490nm and Green 530-550nm).

The objectives mounted on the computer-controlled turret are described in the following table:

The Accurion EP3-BAM is used to image thin films on solid or liquid substrates. To obtain image contrast, the BAM uses the principle that at a certain incidence (Brewster) angle the p-polarized laser beam is not reflected at all by the substrate-air interface. The Brewster angle depends only on the refractive index (RI) of the substrate and is equal to 53° in the case of a water substrate. At this incidence angle, nano-thick molecular and/or nanoparticle films that are spread at the water surface will modify locally the RI value, thus yielding a non-zero reflection coefficient and providing image contrast.

Instrument parameters:

• • Light source: laser unit λ 532nm
  • Imaging system CCD camera 768 x 572px
  • Imaging optics:
    • 10X CF Plan Nikon Objective: NA/0.21; Working distance/20.3mm
    • 20X CF Plan Nikon Objective: NA/0.21; Working distance/20.3mm

• • Motorized goniometer:
    • Angle of incidence (AOI) range: 40-90°
    • Angle resolution: 0.001°
    • Absolute angle accuracy: 0.01°

Characteristics:

• V-750 Jasco
• Double-beam spectrophotometer with single monochromator
• Silicon photodiode detectors
• Range 190 to 1100 nm
• Fixed bandpass of 1.5 nm
• High-speed scanning up to 8,000 nm/min
• Temperature range: 20 to 70°C

The Nanodrop is a compact, stand-alone UV-Visible spectrophotometer for micro volume analysis of purified nucleic acids and wide variety of proteins.

Minimum Sample Volume 1 μL

Limit of Detection dsDNA

• • •  Pedestal: 2.0 ng/μL
    • Standard Cuvette:  0.2 ng/μL

Limit of Detection BSA (IgG)

• • • Pedestal: 0.06 (0.03) mg/mL
    • Standard Cuvette:  0.006 (0.003) mg/mL

Maximum Concentration

• • • dsDNA Pedestal:    27,500 ng/μL
    • BSA (IgG) Pedestal:  820 (400) mg/mL

Wavelength

• • • Range     190 - 850 nm
    • Accuracy  ∓1 nm

Pathlength 0.030 to 1.0 mm auto-ranging

The ALV CGS-3 Compact Goniometer System (ALV GmbH, Langen, FRG) allows for a simultaneous measurement of static and dynamic light scattering. The temperature can be set between 5°C and 50°C.

Static light scattering (SLS) measures the form factor in the angular range of 17° and 152° (equivalent to Qmax ≈ 0.00255 Å-1, depending on solvent index of refraction).

Combining these techniques yields a supplementary information, the structure sensitive parameter ρ (ρ = RG/RH). It allows for an (overall) shape characterization of particles (e. g. sphere, rod, coil etc.).

The Zetasizer Nano Z is the perfect system for measuring zeta potential and electrophoretic mobility of colloids and nanoparticles, when the measurement of size or molecular weight is not required. Laser Doppler Micro-electrophoresis is used to measure zeta potential. An electric field is applied to a solution of molecules or a dispersion of particles, which then move with a velocity related to their zeta potential. This velocity is measured using a patented laser interferometric technique called M3-PALS (Phase analysis Light Scattering). This enables the calculation of electrophoretic mobility, and from this, the zeta potential and zeta potential distribution.

Minimum sample volume: 150 μl Temperature control range: 0°C - 90°C (+/-0.5%) Light Source: He-Ne laser 633nm, Max 5mW. Laser safety: Class 1 Temperature: 15°C – 40°C Humidity: 35% - 80% non-condensing

SOURCE www.malvern.com

A Beaglehole Picometer Light ellipsometer is optimised for interfacial characterisation at the air/liquid and air/solid interfaces. The interfacial excess can be determined to a precision and sensitivity of < 5% of a surfactant monolayer, and with complementary information or optical modelling the data can be used to quantify the adsorbed amount of material at an interface. Data can be acquired at a rate of up to 200 Hz, hence the instrument provides access to the study of fast adsorption kinetics.

The ellipsometer offers two principal benefits to  users. First, it can be used as a pre-screening tool to characterise the kinetics and homogeneity of samples before neutron reflectometry (NR) beam time on FIGARO. Also, the interfacial excess of surface-active material may be compared precisely with respect to a changing variable such as solution composition or temperature. Second, the technique has greater sensitivity to species with a similar scattering length density to that of air (e.g. hydrogenated polymers). Therefore the acquisition of an "optical contrast" during NR measurements can reduce the need for as many NR isotopic contrasts thus saving beam time and deuterated chemicals. Kinetic information may be quantified to complement further the neutron reflectometry data, and inhomogeneity in free liquid surfaces can be identified prior to the modelling of NR data.

The BAM utilizes the fact that when p-polarized light is guided towards an air-water interface, no reflection occurs at a certain incident angle. This angle, the Brewster angle, is determined by Snell's law and depends on the refractive indices of the materials in the system. The Brewster angle for the air-water interface is 53°, and under this condition the image of a pure water surface appears black. Addition of material to the air-water interface modifies the local refractive index (RI), and hence, a small amount of light is reflected and displayed within the image. The image displayed contains areas of varying brightness determined by the particular molecules and packing densities across the sampling area.

Lateral resolution ≥1µm

Nima Langmuir trough 1212D used for the preparation of layers on solid substrates from insoluble amphiphilic molecules, typically lipids but also polymers and proteins.

• Trough surface 680x200 mm²
• 2 independent barriers
• Dipper and well at center
• Dimensions well: 90x110 mm² 85mm deep
• Temperature control
• Pressure sensor uses a Wilhelmy plate (chromatography paper of wet perimeter 20.6mm weight 80mg/m²)
• Manual and automatic system for Langmuir-Schaefer deposition optimized for 80x50 mm² silicon substrates

Nima 611 Langmuir trough used for the preparation of layers on solid substrates from insoluble amphiphilic molecules, typically lipids but also polymers and proteins.

• Trough surface 300x200 mm²
• 1 barrier
• Dipper and well at one end
• Dimensions well: 63x180 mm² 70mm deep
• Temperature control
• Pressure sensor uses a Wilhelmy plate (chromatography paper of wet perimeter 20.6mm weight 80mg/m²)
• Manual system for Langmuir-Schaefer deposition optimized for 50mm wide squared substrates

Nima Langmuir trough 712BAM used for the preparation of molecular layers on water surfaces from insoluble amphiphilic molecules, typically lipids but also polymers and proteins. Such layers can also be transferred to solid substrates by the built-in accessory allowing Langmuir-Blodgett deposition.

Langmuir trough characteristics:

• Maximum area: 716 cm²
• Minimum area: 30 cm²
• Barrier speed max: 654.2 cm².min^-1
• Barrier speed min: 5.2cm².min^-1
• Dimension well (Area-Deep): 50x20mm²-30mm

Transfer arm type D1L:

• Amplitude: 25 mm
• Speed: Min 0.5 - Max 44.5 mm.min^-1

KSV Nima KN-1002  is a small Langmuir trough used for the preparation of layers at the air/water interface

• Trough surface 195 x 50 mm²
• Maximal compression ratio: 5.2
• 2 barriers

Fully automatic determination of surface and interfacial tension for routine measurements in laboratory and quality control applications.

Measuring methods:

• Ring method (Du Noüy; correction acc. To Huh&Mason, Harkins&Jordan; Zuidema&Waters)
• Plate method (Wilhelmy)
• Temperature range: 5 to 90°C
• Measuring range: SFT / IFT 1 to 999 mN/m, Density: 1 to 2200 kg/m³

A Beaglehole Picometer Light ellipsometer is optimised for interfacial characterisation at the air/liquid and air/solid interfaces. The interfacial excess can be determined to a precision and sensitivity of < 5% of a surfactant monolayer, and with complementary information or optical modelling the data can be used to quantify the adsorbed amount of material at an interface. Data can be acquired at a rate of up to 200 Hz, hence the instrument provides access to the study of fast adsorption kinetics.

The ellipsometer offers two principal benefits to  users. First, it can be used as a pre-screening tool to characterise the kinetics and homogeneity of samples before neutron reflectometry (NR) beam time on FIGARO. Also, the interfacial excess of surface-active material may be compared precisely with respect to a changing variable such as solution composition or temperature. Second, the technique has greater sensitivity to species with a similar scattering length density to that of air (e.g. hydrogenated polymers). Therefore the acquisition of an "optical contrast" during NR measurements can reduce the need for as many NR isotopic contrasts thus saving beam time and deuterated chemicals. Kinetic information may be quantified to complement further the neutron reflectometry data, and inhomogeneity in free liquid surfaces can be identified prior to the modelling of NR data.

The QCM is a mass sensing device with the ability to measure very small masses changes on a quartz crystal resonator in real time. It is possible to measure mass changes as small as a fraction of monolayer or single layer of atoms. As the second generation of Quartz Crystal Microbalance with Dissipation monitoring (QCM-D) from Q-Sense, the E4 offers the opportunity to study molecular interactions and molecular adsorption to many different types of surfaces. Applications include proteins, lipids, polyelectrolytes, polymers and cells/bacteria interacting with surfaces or with previously bound molecular layers.

The instrument determines the mass of very thin surface bound layers and simultaneously gives information about their structural (viscoelastic) properties. It is based on the patented QCM-D technique, an extremely sensitive and fast technique providing multi-frequency and dissipation data that are needed to fully understand the state of molecular layers bound to the sensor surface.

• Number of sensors 4, also possible to measure using only 1, 2 or 3 sensors
• Volume above each sensor ~ 40 µl using Q-Sense Flow Module for 5 MHz crystals
• Minimum sample volume ~ 200 µl
• Working temperature 18 to 45 °C, controlled via the software, stability ± 0.02 K
• Flow rates 0-1 ml/min
• Sensor crystals 5 MHz, 14 mm diameter, polished, AT-cut, gold electrodes

This is an "home made" ellipsometer by Patrice Ballet at the University Joseph Fourier (Grenoble).

The principle of this rotating quarter wave plate ellipsometer can be found at this address : http://pagesperso-orange.fr/aime.vareille/pages/ellipsometrie/

The laser diodes 2 & 3 are required to find the number of periods of the signal.

The signal acquisition is done with an A/D conversion card at 100 kHz and with a resolution of 16 bits.

The angle of incidence is set to silicon (75 °) but can be changed between 0 and 90 degrees.

This instrument allows the rheological characterization of the flow behaviour and viscoelastic properties of complex fluids and bulk soft matter systems. Seven different measuring geometries are available in cone-plate (C20/2.0° Ti L; C20/4.0° Ti L and C60/1.0° Ti L), plate-plate (P20 Ti L and P60 Ti L) and Couette (CC16 DIN Ti and CC25 DIN Ti) configuration. Two Peltier controllers allow sample temperature regulation during the measurement in the range from 5 °C up to 85 °C with 0.1°C precision.

• • Angular resolution: 12 nrad
  • Minimum torque in rotation: M_min 0.05 mN.m
  • Minimum torque in oscillation: M_min 0.25 mN.m
  • Maximum torque: M_max 200 mN.m

• • Couette: (Rotor diameter in mm / Sample Volume in mL): 25/16.1 and 16/3.95
  • Plate/Plate(Diameter ∅ in mm / angle): 60/0° and 20/0°
  • Cone-Plate(Diameter ∅ in mm / angle): 20/2°; 20/4° and 60/1°