MicroVacuum QCM-I Mini User manual

Volume 1. QCM-I Mini and eQCM-I Mini User Manual Rev3
QCM-I Mini and eQCM-I Mini Operator’s Manual Edition: 2018/12
© MicroVacuum Revision: 3
1
QCM-I Mini and eQCM-I Mini
QUARTZ CRYSTAL MICROBALANCE WITH
IMPEDANCE ANALYSIS
User Manual
 1993-2018 MicroVacuum Ltd.
Kerékgyártó u. 10, Budapest, H-1147, Hungary
Phone [phone] • Fax [phone]
E-mail: [e-mail]
Web: http://www.microvacuum.com/
Volume

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QCM-I Mini and eQCM-I Mini User Manual Edition: 2018/12
© MicroVacuum Revision: 3
TABLE OF CONTENT S
SAFETY ............................................................................................................................................................... 5
1.
General Safety .............................................................................................................................................................................. 5
Measuring Head, Sensor Holder and Flow Cell ............................................................................................................................. 6
INTRODUCTION .................................................................................................................................................. 7
2.
QCM-I MINI PRINCIPLE OF OPERATION .............................................................................................................. 8
3.
3.1 QCM-I MEASUREMENT PRINCIPLE ............................................................................................................................... 8
3.2 LIMITS OF OPERATION ................................................................................................................................................ 9
Assumptions ................................................................................................................................................................................. 9
Maximum Loads ......................................................................................................................................................................... 10
3.3 LOCATING RESONANT FREQUENCIES ............................................................................................................................ 10
3.4 RESONANCE CURVE ANALYSIS .................................................................................................................................... 10
Resonance Modeling (Lorentz curve) ......................................................................................................................................... 10
3.5 QCM-I MINI INSTRUMENT DESCRIPTION ..................................................................................................................... 12
General ....................................................................................................................................................................................... 12
Temperature Measurement and Temperature Control Module ................................................................................................ 13
Power Supplies (External) ........................................................................................................................................................... 13
PC for Running BioSense Software ............................................................................................................................................. 13
BioSense Software ...................................................................................................................................................................... 13
Measurement Channels .............................................................................................................................................................. 13
Built-in Thermal Chamber and Sensor Holder with Flow-Cell ..................................................................................................... 13
External Sensor Holder ............................................................................................................................................................... 13
3.6 ELECTROCHEMICAL QCM-I........................................................................................................................................ 13
Potentiostat ................................................................................................................................................................................ 14
3.7
QCM-I M
INI
S
PECIFICATION
.................................................................................................................................... 15
GETTING THE EQUIPMENT READY FOR USE ...................................................................................................... 16
4.
4.1 UNPACKING QCM-I MINI ......................................................................................................................................... 16
4.2 UNPACKING THE COMPUTER ...................................................................................................................................... 16
4.3 QCM-I MINI INSTALLATION WITH MICROSOFT SURFACE PRO .......................................................................................... 17
USB Hub Accessory ..................................................................................................................................................................... 17
4.4 INSTALLATION USING DESKTOP PC OR NUC COMPUTER .................................................................................................. 19
4.5 INSTRUMENT TESTING .............................................................................................................................................. 21
4.6 EQCM-I INSTALLATION ............................................................................................................................................. 21
4.7 EQCM-I ELECTRODE CONNECTIONS ............................................................................................................................ 21
TEMPERATURE CONTROL ................................................................................................................................. 23
5.
SENSORS .......................................................................................................................................................... 24
6.
6.1 SENSORS ................................................................................................................................................................ 24
Geometry .................................................................................................................................................................................... 24
Electrode Materials..................................................................................................................................................................... 25
Electrode Coatings ...................................................................................................................................................................... 25

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6.2 SENSOR LIFE AND PERFORMANCE................................................................................................................................ 25
Useful Life ................................................................................................................................................................................... 25
Temperature Effects ................................................................................................................................................................... 26
6.3 SENSOR HANDLING .................................................................................................................................................. 26
6.4 SENSOR CLEANING ................................................................................................................................................... 27
UV-Ozone Cleaning ..................................................................................................................................................................... 28
Basic Piranha ............................................................................................................................................................................... 28
Acid Piranha ................................................................................................................................................................................ 28
Detergent .................................................................................................................................................................................... 29
Other Cleaning Methods............................................................................................................................................................. 29
FLOW CELL ASSEMBLY ...................................................................................................................................... 30
7.
7.1 STANDARD FLOW CELL ASSEMBLY ............................................................................................................................... 30
7.2 ELECTROCHEMICAL FLOW CELL ASSEMBLY .................................................................................................................... 32
FLOW-CELL FLUIDIC CONFIGURATIONS ............................................................................................................ 33
8.
8.1 PREPARING SOLUTIONS ............................................................................................................................................. 33
8.2 MANUAL STATIC CELL ............................................................................................................................................... 33
8.3 PERISTALTIC PUMP ................................................................................................................................................... 34
8.4 PERISTALTIC PUMP AND SELECTOR VALVE ..................................................................................................................... 35
8.5 PERISTALTIC PUMP AND SAMPLE INJECTION VALVE ........................................................................................................ 35
SENSOR HOLDERS, ADAPTORS AND MODULES ................................................................................................ 37
9.
Standard Flow Cell ...................................................................................................................................................................... 37
Dummy Sensor Module .............................................................................................................................................................. 37
Immersion and Open Sensor Holder ........................................................................................................................................... 38
Electrochemical Flow Cell ........................................................................................................................................................... 38
Ag/AgCl Reference Electrode ...................................................................................................................................................... 38
High Pressure Sensor Holder ...................................................................................................................................................... 39
Vacuum Sensor Holder ............................................................................................................................................................... 40
Microscopy ................................................................................................................................................................................. 40
Low Profile Holder ...................................................................................................................................................................... 41
Channel A: External Sensor-Holder Adaptor ............................................................................................................................... 41
Calibration Kit ............................................................................................................................................................................. 42
Custom External Sensor-Holder .................................................................................................................................................. 42
BIOSENSE 3 SOFTWARE FOR QCM-I MINI ......................................................................................................... 43
10.
10.1 USER LOGIN ....................................................................................................................................................... 43
Evaluation Mode ......................................................................................................................................................................... 43
TROUBLESHOOTING ......................................................................................................................................... 43
11.
11.1 ERROR MESSAGES ............................................................................................................................................... 43
SUPPORT .......................................................................................................................................................... 44
12.
12.1 HOW TO ESTABLISH REMOTE CONTACT? ................................................................................................................. 44
WARRANTY ...................................................................................................................................................... 45
13.
APPENDIX 1: SENSOR DATA SHEETS ................................................................................................................. 46
14.
APPENDIX 2: SENSOR-HOLDER MODULE DATA SHEETS .................................................................................... 47
15.

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QCM-I Mini and eQCM-I Mini User Manual Edition: 2018/12
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Windows® and Excel® are registered trademarks of the Microsoft Corporation

Safety 5
QCM-I Mini and eQCM-I Mini User Manual Edition: 2018/12
© MicroVacuum Revision: 3
Safety
1.
In no event shall MicroVacuum ever be held responsible or liable for any direct, indirect, incidental,
special or consequential damages or costs whatsoever resulting from or related to the use or misuse of
the QCM-I Mini instrument or components thereof, even if MicroVacuum has been advised, knows of,
or should be aware of the possibility of such damages. MicroVacuum emphasizes the importance of
consulting experienced and qualified professionals to assure the best results when using the QCM-I
Mini.
General Safety
WARNING!
The safety requirements listed in this manual must be followed in order to avoid personal injury and
damage to the QCM-I Mini instruments.
WARNING!
RISK OF ELECTRICAL SHOCK. Do not connect this instrument to electrical power if the enclosure is
damaged or any of the covers or panels is removed. Make sure the voltage rating on the
instrumentation matches the line voltage available in the lab. Connect only to outlets with safety earth
ground. Make sure that the power cord is easily accessible when the equipment has been installed.
WARNING!
RISK OF ELECTRICAL SHOCK OR FIRE HAZARD. Switches may produce electrical sparks. Do not
use the QCM-I Mini instruments in the presence of flammable gases, fumes or liquids.
The instrument has been designed for indoor use only. Do not expose it to rain, snow or dust. During
storage or transport the instrument should be kept dry. Temperatures below 0ºC and above 65ºC
should be avoided. Do not operate at ambient temperatures below 5ºC and above 30ºC.
CAUTION!
Use only as specified in the operating instructions. Follow all instructions. Skipping steps can result in
damage to the QCM-I Mini instrument.
Handle carefully when removing the instrument from the transport packaging. The product must always
be shipped in either the original packaging supplied with the QCM-I Mini, or equivalent.
CAUTION!
Do not use force when connecting or disconnecting connectors as damage may occur.
Do not subject the equipment to external shocks.
Do not block or restrict ventilation slots.
Do not expose any parts other than the sample volume in the flow module(s) to water or other liquids.
CAUTION!
If liquid is spilled on the instrument, disconnect it from the power source and have it checked by an
authorized person.
Refer to the safety information from the supplier and general safety regulations in your country when
you work with chemicals.
Carry out appropriate decontamination if equipment is exposed to hazardous material.
Do not install substitute parts or perform any unauthorized modification to the product.
Return the product to MicroVacuum or other qualified and authorized personnel for service and repair to
ensure that safety features are maintained. Before returning the instrument it must be free of hazardous
contamination.
For safety instructions and operation of peripheral equipment, e.g. the personal computer, read the
safety instructions and the manual provided by the manufacturer carefully.

Safety 6
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Turn the QCM-I Mini or eQCM-I Mini off when not in use. An appropriate risk assessment should be
undertaken before the instrument is left operating unattended.
Measuring Head, Sensor Holder and Flow Cell
WARNING!
RISK OF FIRE HAZARD. Use only sample liquids with a self-ignition point higher than 85°C in the
sample volume of the flow modules.
Parts of the sensor holder and flow cells can become hot.
Do not expose any parts other than the sample volume to water and other liquids.
If liquid is spilled inside the electronics part of the sensor holder, disconnect it from the electronics unit
and have it checked by an authorized person.

Introduction 7
QCM-I Mini and eQCM-I Mini User Manual Edition: 2018/12
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Introduction
2.
The QCM-I Mini is a precision instrument for the determination of the mass and viscoelastic properties
of thin films attached to the surface of a quartz crystal sensor. These films, which may be a wide range
of molecular or atomic layers from metals to physisorbed polymers, surfactants or immobilized
biological samples, are monitored in real time either in liquid or in the vapor phase. The measurement
is made by monitoring the change in resonant frequency spectrum of the oscillating piezoelectric sensor
crystal. In water the acoustic transverse wave created extends into the solution above the sensor
surface, decaying rapidly with a penetration depth of ~250 nm for a 5 MHz crystal. The technique can
measure changes in the layers over a nm to micron thickness range or ng/cm2 to g/cm2 mass range,
as well as changes in the solution viscosity. In solution, the mass determined is the “wet mass” or
hydrated mass which corresponds to the solid material that makes up the film as well as solvent and
ions etc. that are contained within the film and closely coupled to the oscillation of the film.
This manual describes the principles of operation and how to set up the instrument together with safety
and technical information for the correct operation and maintenance of the QCM-I Mini. It is important
that the user familiarize themselves with these requirements if the equipment is to be operated correctly
and to its best. Please read all sections before using the equipment.
As with all precision instruments, it is not recommended that the user undertake maintenance or
calibration unless specifically trained to do so by the manufacturer. If for whatever reason the
instrument ceases to operate correctly, the user should contact the vendor for guidance on whether the
instrument needs to be serviced by a qualified service engineer or returned to the vendor for repair.
Under no circumstances should the instrument be dismantled or operated without the fitted cover and
attention should be taken at all times to the warnings detailed in the operator’s manual.
This User Manual (Volume 1) which focuses on the hardware aspects of the instrument should be read
in conjunction with the Software Manual (Volume 2) also provided with the equipment.

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QCM-I Mini Principle of Operation
3.
3.1 QCM-I MEASUREMENT PRINCIPLE
The Quartz Crystal Microbalance (QCM) technique monitors the resonant frequency of a piezoelectric
quartz crystal sensor in response to an alternating voltage applied between electrodes on its two faces.
The crystals are cut so that they oscillate in a thickness shear mode, with opposing faces travelling in
opposite directions as shown in Figure 1. AT-cut quartz crystals are most commonly used as QCM
sensors because of their superior mechanical and piezoelectric properties, and because they can be
cut to give nearly zero temperature coefficients at room temperature. The resonant frequency
corresponds to the excitation of the acoustic standing wave across the thickness of the quartz and top
and bottom electrodes. If a thin rigid layer is added to the surface of one of the electrodes, the acoustic
wave extends through this layer and the resonant frequency drops. The reduction in the frequency can
be related to the change in areal mass (m/A) on the surface of one side of the crystal by the
Sauerbrey equation1:
fn = -2n.f12.(m/A)/(qq)½ (Hz) (1)
m/Afn .(qq)½ / (-2n.f12) (ng/cm2) (2)
Where fn is the change in resonant frequency of the nth overtone of a crystal of fundamental frequency
f1, m is the change in mass (g), A is the area (cm2), q is the density of quartz (2.648 g/cm3) and q is
the Shear Modulus of quartz (2.947x1011 gcm-1s-2).
For a crystal with fundamental frequency of 5 MHz, its mass sensitivity [m/(f.A)] is -17.7 ngcm-2/Hz.
The areal mass data from the Sauerbrey equation can also be expressed as a (Sauerbrey) thickness
(ds) by using an estimated density for the layer , which is often taken as 1 gcm-3.
ds = (m/A) / (.100) (nm) (3)
The crystal can also oscillate at overtone frequencies, which correspond to the odd harmonics; 3x, 5x,
7x etc. and measurements can also be made at these frequencies.
Figure 1: Schematic diagram of a QCM measurement, showing the shear displacement of the quartz at
fundamental and 3rd harmonic frequencies. The plot shows a conductance-frequency response obtained from an
impedance measurement with a network analyzer; resonant frequency and band width are marked.
In the QCM-I technique the resonant frequency is obtained using a network analyzer, which measures
the impedance spectrum of the crystal as a function of frequency. The resonant peak obtained at the
fundamental frequency is also shown in Figure 1. In addition to the frequency of the resonant
maximum, the Full Width at Half Maximum (FWHM) is also obtained. The FWHM can be related to the
dissipation (D, determined by QCM-D using the “ring-down” technique) and is inversely proportional to
the Quality factor (Q) of the crystal:
1 Sauerbrey, G. Z. Phys. 1955, 155, 206.

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FWHM / f = D = 1/Q (4)
The FWHM/f measured from the impedance and D measured by the ring-down technique (QCM-D)
have been shown to be the same parameter, just measured in two different ways2.
When a rigid film is deposited on the sensor surface, the FWHM does not change and f/n is the same
for the fundamental frequency and the overtones. However, if a bare crystal is immersed in a viscous
liquid, or if a viscoelastic film is deposited on the sensor surface from solution, then as well as a
reduction in the frequency, the FWHM will increase; this is shown in Figure 2. For a viscoelastic layer
the frequency change, fn/n, is also smaller for higher overtones.
The QCM-I signal Frequency and FWHM response to the viscosity and density of Newtonian solution
(s) is given by3:
fn = -n1/2 f13/2 (ss )1/2 / (qq)1/2 (Hz) (5)
FWHM = 2 n1/2f13/2 (ss )1/2 / (qq)1/2 (Hz) (6)
This means that the response measured for a bulk solution change, due to different viscosity or density
of the new solution follows the relationship: FWHMn/fn= 2.
Figure 2: Change in resonance of a bare QCM sensor (blue) on immersion in a liquid (red).
3.2 LIMITS OF OPERATION
Assumptions
Measurements can be made for the deposition of a very wide range of layers, however analysis of film
properties generally makes the following assumptions:
 Uniform film distribution – the surface is completely covered with a uniform film
 Good adhesion of the film to the surface
 Thin film approximation – the film thickness is significantly less than the thickness of the crystal
 Rigid layer – Sauerbrey analysis to directly determine the mass from the frequency change
requires this, otherwise visco-eleastic models are required to stop underestimation of the mass
change. The extent of the error is dependent on the film thickness as well as the solution
viscosity, if the measurement is in solution.
2 D. Johannsmann, Viscoelastic, mechanical and dielectric measurements on complex samples with the
quartz crystal microbalance. Phys. Chem. Chem. Phys. 10, 4516–4534 (2008)
3 K. Kanazawa, J. G. Gordon, Anal. Chim. Acta 1985, 175, 99–105.

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For data analysis and more complex modelling of QCM experiments where overtone data is available,
the fundamental frequency is often not used because it does not always fit consistently with the
overtone data. For some instruments it may also not be commonly measured due to issues with signal
stability. The reason for this is likely to be due to the magnitude of displacement at the crystal surface,
which is approximately inversely proportional to square of the overtone number. Ie. the surface
displacement U0 at the fundamental frequency is 9x that of the 3rd harmonic at the same Q.
U0 = 4UelQq/(n)2 (7)
Where Uel is the electrical driving amplitude, Q the crystal quality factor, q is the piezoelectric strain
coefficient (3.1 x 10-12 m/V for AT cut quartz) and n is the overtone number.
This is likely to make it more sensitive to edge effects or stresses within the crystal. However for non-
rigid layers, the lower the harmonic, the closer the calculated Sauerbrey mass will be to the actual
hydrated mass. Indeed for some systems, such as coupled nanoparticles or vesicles, the reduction of
the frequency response for the overtones can be so large that the fundamental and overtones give
apparent mass changes in opposite directions and potentially wholly incorrect interpretation of the data
if only the overtone data is collected. For this reason it is recommended that the fundamental frequency
data is always collected.
Maximum Loads
QCM sensor crystals can be coated with virtually any material as long as it can be deposited in a
sufficiently thin, uniform and well-attached layer. Layer thicknesses typically vary from a few Angstrom
to a few micrometers. The maximum layer thickness depends on the viscoelastic properties of the
coating material. As a general rule, thicker layers are possible for more rigid coating materials.
The maximum load on a crystal is limited by two factors: (1) total damping or (2) lost sensitivity. For
highly viscous or solid materials, the damping of the crystal increases with increasing layer thickness.
At a certain thickness (usually a couple of micrometers) the damping becomes so high that the crystal
can no longer be driven, i.e. the measurement fails due to lack of oscillation. More elastic materials do
not couple completely to the crystal’s oscillation. With increasing layer thickness the outermost parts of
the attached layer will couple weakly and at a certain thickness (usually a few micrometers) it is lost
completely. Oscillation is still detected, and a frequency is still measured, but the equipment can only
sense the part of the layer in the vicinity of the crystal-layer interface.
3.3 LOCATING RESONANT FREQUENCIES
In order to determine the resonant frequencies to track for a measurement, during the measurement
initialization, the network analyzer scans through a wider frequency range measuring the sensor crystal
admittance (1/impedance) based on the nominal crystal frequency. Once it has identified conductance
maxima within this region it selects a narrower region to make measurements at smaller frequency
intervals for a better defined resonance curve. The user can do a similar scan using the network
analyser (Frequency Scan) between any frequencies from 0.05 to 80 MHz.
3.4 RESONANCE CURVE ANALYSIS
Resonance Modeling (Lorentz curve)
For each of the selected sensor resonances, the conductance (G) and susceptance (B) values as a
function of frequency (the real and imaginary components of the admittance) are fitted to a Lorentzian
model for the Crystal oscillator. The fit parameters are Gmax, FWHM, Frequency, Goff, Boff, Fi and
residual, derived from the equivalent circuit4, shown in Figure 3. The resonant frequency and FWHM
4 D. Johannsmann, The Quartz Crystal Microbalance in Soft Matter Research: Fundamentals and Modeling,
Springer International Publishing, Switzerland, 2015.

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values are used for the film characterization. The parameters Fi and Goff account for effects of the
connection of the sensor crystal to the analyzer or small errors in the instrument calibration.
Figure 3: Simulated plot of conductance and susceptance from a crystal impedance measurement and equivalent
electrical circuit on which the analysis is based.
The standard acquisition measures 200 frequency points for the curve fit, which limits the acquisition
rate but gives high resolution. Fewer points are measured in Fast mode, 20, which increases the
acquisition rate but also increases the noise.
Whilst the resonance curves (frequency spectra) can be saved during the experiment, in the interests of
data file size, only the fitted parameters are recorded as the time dependent experimental data. The
parameters returned from the fit of the resonance data and saved as the experimental data are:
 Frequency (the resonant frequency of the selected overtone, Hz),
 FWHM (full width half maximum of the resonance peak, Hz),
 Gmax (conductance maximum from the fit of the resonance curve,)
 Goffs (conductance offset from the fit of the resonance curve,)
 Boffs (susceptance offset from the fit of the resonance curve,)
 Fi (phase rotation of G and B components from the fit of the resonance curve,)
 Residual (the difference between the fitted curve and the measured data from the Lorentz
fit of the resonance curve,)
From the fit parameters the following data can be derived and output:
 Q (Quality factor) and Dissipation,
 Frequency (frequency change from start of experiment or baseline, Hz)
 FWHM (change in resonant peak width, Hz,)
 Dissipation (change in dissipation from the start of the experiment)
 Sauerbrey Mass (Mass calculated using the Sauerbrey equation from the beginning of the
experiment or baseline, ng/cm2; if Sauerbrey is selected as the Calculation Model.)
Other experimental data is also recorded from the experiment, depending on modules installed, such
as:
 Temperature (measured on channel A,)
 Flow (where fluidic pump control option is enabled,)

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3.5 QCM-I Mini INSTRUMENT DESCRIPTION
General
The QCM-I Mini instrument consists of the following modules:
 QCM-I Mini measuring unit including
o Impedance measurement circuit
o Electronic signal processing and controlling unit
o Temperature control unit
o Built-in thermal chamber(Channel A) and sensor holder with flow-cell
o SMA Female panel mount connector for external sensor holder (Channel B)
o Working electrode connector for electrochemical cell (2 mm banana socket)
 External sensor holder (Channel B) – various options
 External Power supply
 External PC with installed MS WindowsTM operation system
 Pre-installed BioSense software for controlling QCM-I Mini measurement.
Figure 4: QCM-I Mini measurement unit front view
Figure 5: QCM-I Mini measurement unit rear view (left) and underside showing EC working electrode connector
(right).
The signals are generated and data is collected in the QCM-I Mini measuring unit before being sent to
the computer.
The PC communicates with the QCM-I Mini unit via Manufacturer supplied USB cable. Microsoft
Windows™ 10 Pro operating system is installed on the PC.
Channel A
Thermal Chamber
Channel B
SMA-F Connector
Temperature
Controller
Working electrode
connector socket
Working Electrode
2mm
Banana Connector

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The BioSense software controls the measuring unit, performs the data processing, computations and
displays/saves/exports/imports the results.
Temperature Measurement and Temperature Control Module
The thermal chamber/ measuring head (Channel A) of the QCM-I Mini unit is heated/cooled by a Peltier
device controlled by a temperature controller built-into the QCM-I Mini instrument.
Power Supplies (External)
QCM-I Mini is powered with a DC power adapter:
 Only use the manufacturer supplied Power Supply. E.g. XP Power, model: AFM60US12. (Medical
grade, 12V DC, 5A output, output center pin positive, output 0 V is electrically connected to Input
Ground.)
PC for Running BioSense Software
The PC is part of the QCM-I Mini system. It is delivered by MicroVacuum with pre-installed Windows®
10 operation system and BioSense software. For reliable and fast QCM operation this computer should
only be used for running the BioSense software and only with the preinstalled software.
Do not install any third party software on this PC as it may affect the proper operation of the instrument.
BioSense Software
BioSense is Windows-based software for full control of QCM-I Mini instrument.
Measurement Channels
Two QCM measuring channels are available with the QCM-I Mini:
• Channel A – temperature controlled built-in thermal chamber which takes a modular sensor-
holder with flow cell, or adaptor for external sensor-holder. Both sensor electrodes are isolated
from earth.
• Channel B – SMA female connector for an external sensor holder. The threaded outer is
connected to the instrument case and earth.
Built-in Thermal Chamber and Sensor Holder with Flow-Cell
The QCM sensor chip is placed in the sensor holder that supports the quartz crystal between two “ O “
rings. The wetted part of this sensor holder is made of PEEK or stainless steel and serves as a flow
cell for the QCM crystal. The sensor holder is placed in a temperature controlled measuring head that
keeps the sensor and the flow cell at a well-controlled temperature.
External Sensor Holder
There is a sensor connector (Channel B) on the front face of the QCM-I Mini for connecting to external
sensor holders, see Figure 4. A range of holders and custom holders are available for different
applications, detailed in chapter 9 of this manual.
3.6 ELECTROCHEMICAL QCM-I
The QCM-I Mini can be used as an electrochemical QCM (eQCM) for combined electrochemical and
microbalance measurements. This requires electrochemical flow-cell and software modules. eQCM
measurements enable the mass changes at the QCM sensing electrode surface to be monitored as a
function of the electrochemical potential and the current and charge passed. The setup is shown
schematically in Figure 6.

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Figure 6: Schematic EQCM-I
Potentiostat
An external potentiostat is used to control the electrochemical measurement. An electrochemistry
module is available for the BioSense 3 software to integrate measurements using Gamry and
MicroVacuum supplied potentiostats.

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3.7
QCM-I Mini SPECIFICATION
Technical Information QCM-I Mini
Measurement Channels
2
1st : Temperature controlled
2nd : Connection for external sensor-holder modules
Frequency Range 1-80 MHz, up to the 13th overtone for a 5 MHz Crystal
Measurement Modes Frequency Scan, Resonance, QCM(t), QCM(t)-EC, EC
Resonance Frequency sensitivity in Liquid ≤ 2 x 10-1 Hz
Dissipation Sensitivity in Liquid ≤ 1 x 10-7
Mass Sensitivity in Liquid * ~ 1 ng/ cm2
QCM-I parameters at each Overtone Resonance Curve, (Frequency, (FWHM, Q,
(Dissipation, Temperature, etc.
Temperature Control
Working Temperature 15 oC to 65 oC
Temperature Stability ± 0.02 oC
Temperature control Set manually or via software
Fluidic and Sample
Flow Cell Volume ~ 40 µl (typical with Ø14 mm crystals)
Wetted Parts PTFE, PEEK, SS, VITON (or Kalrez )
Sample Loading Customer Supplied or Integrated Options
Pump Customer Supplied, Syringe Pump or Integrated Peristaltic
Options
Other Sample Cell Options
Electrochemical flow-cell, Open Cuvette, Immersion,
Vacuum, High-pressure, Low-profile, Ellipsometry,
Microscopy, Custom...
Physical Dimensions ( without the computer )
Dimensions, weight 180 mm x 175 mm x 68mm, 1.35 Kg
Software
BioSense Universal software platform for QCM & EC measurements
Import / Export of data Export to third party software Excel, JPG, BPM, WMF etc.
PC Control USB 2.0, Windows® 10
Electrical
Power Supply 12VDC power supply with universal input voltage
( 100V-240V AC / 50-60 Hz )
Table 1: QCM-I Technical Specification
* Based on BioSense analysis using Sauerbrey equation and with data smoothing option enabled.

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Getting the Equipment Ready for Use
4.
4.1 UNPACKING QCM-I Mini
The QCM-I Mini is a sensitive instrument and should be handled with care. Take the QCM-I Mini
instrument out of the cardboard box, remove the plastic protecting cover and place it on the working
bench.
The accessories are in a separate box. Please check the content according to the detailed part list
enclosed in the box.
If any of the components are damaged, please contact the vendor immediately.
Install the QCM-I Mini on a solid, clean, stable, laboratory bench away from direct sources of heat or
draft.
Do not block the ventilation openings on the bottom and side of the equipment. Ensure that the
laboratory power supply is suitable for the power adapters provided.
4.2 UNPACKING THE COMPUTER
Please follow the steps in the PC Manual. The PC is delivered with installed MS Windows™ 10 and
BioSense software.
The QCM-I Mini is supplied with either a Microsoft® Surface Pro tablet computer, or with a NUC
computer. The following sections detail the two configurations.

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4.3 QCM-I MINI INSTALLATION WITH MICROSOFT SURFACE PRO
Step 1
With mains (AC) power supply off, plug the Surface Pro transformer into the mains and connect the
magnetic power supply cable to the Surface Pro (as in Figure 8 & Figure 9).
Step 2
Connect the USB cable to the USB socket on the Surface Pro.
Connect the mini-USB end of the cable to the QCM-I Mini.
Use only the white manufacturer-supplied USB A to USB mini B cable.
Connect the 12V power supply to the QCM-I Mini. (as in Figure 7 & Figure 8).
Figure 7: QCM-I Mini
Figure 8: Surface Pro
Step 3
Once all the cables are connected as shown in Figure 9, turn on the power supplies and the Surface
Pro; it should start up immediately. Wait for Windows® to load fully before turning-on the QCM-I
Mini. Turn on the QCM-I Mini by pressing the on/off button shown in Figure 7 for 2 s, or off for 4 s. The
button lights up blue when on.
Start the BioSense software. Log on with Username: user and Password: user. The installation is
complete if the software loads without showing an error message. Please refer to the “Quick Start
Guide”, this User manual and the QCM-I Software Manual for further operating instructions. In the event
of an error message, see the “Trouble Shooting” section at the end of this manual.
 Do not switch off the QCM-I Mini unit while BioSense software is running on the Computer.
 Exit the BioSense software before turning off the QCM-I Mini.

 The computer may operate while QCM-I Mini is switched off. When QCM-I Mini is off the
BioSense software is running in Data Evaluation Mode. The controls are not active, but the
database of the previous measurements is available, and the saved measurements can be
opened and can be evaluated.
USB Hub Accessory
To provide additional connectivity to the Surface Pro tablet e.g. for an electrochemical QCM
potentiostat, the QCM-I Mini can also be installed with a manufacturer supplied USB hub. The Surface
Pro Dock provides USB as well as Ethernet, audio and Mini display ports. This is shown in Figure 10.
Manufacturer supplied
mini-USB to USB cable
ON: Press 2s
OFF: Press 4s
Manufacturer-supplied
mini-USB to USB cable
Surface Pro
Power
12V
Power

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Figure 9: QCM-I Mini with Surface Pro schematic layout
Figure 10: QCM-I Mini, Surface Pro and USB Hub Accessory schematic layout

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4.4 INSTALLATION USING DESKTOP PC OR NUC COMPUTER
Step 1.
With mains power supply off, connect the cables to the PC: Keyboard (USB), Mouse (USB), Power
Supply (19V NUC power supply), Monitor cable (HDMI) and connect the monitor.
Figure 11: NUC PC
Step 2
Connect the QCM-I Mini USB cable to the lower USB socket on the PC. Only use the white
manufacturer-supplied (USB to mini-USB) cable. Connect the mini-USB end of the cable to the
QCM-I Mini. Also connect the 12V QCM-I Mini power supply.
Figure 12: QCM-I Mini rear view
Step 3
Once all the cables are connected as shown in Figure 13, turn on the power supplies and the NUC; it
should start up immediately. Wait for Windows® to load fully before turning-on the QCM-I Mini.
Turn on the QCM-I Mini by pressing the on/off button shown in Figure 12 for 2 s, or off for 4 s. The
button lights up blue when on.
Start the BioSense software. Log on with Username: user and Password: user. The installation is
complete if the software loads without showing an error message. Please refer to the “Quick Start
Guide” or Operator’s Manual for further operating instructions. In the event of an error message, see
the “Trouble Shooting” section at the end of this manual.
Exit the BioSense software before turning off the QCM-I Mini.
Manufacturer supplied
mini-USB to USB cable
ON: Press 2s
OFF: Press 4s
12V Power
Manufacturer supplied
mini-USB to USB cable
HDMI
19V Power

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Figure 13: QCM-I Mini with NUC PC schematic layout