| Q1 |
There are many biosensor companies around. What new
features/benefits does Silicon Kinetics offer? |
| A1 |
Silicon Kinetics SKi Pro™ platform is unique in
several respects. First, rather than the traditional planar biosensor
surfaces, SKi Pro offers a 3D biosensor surface in nanoporous silicon. 3D
surface has advantages in sensitivity (for example, in measuring very slow
off-rates) and analyte capture in some applications. Secondly, SKi Pro is the
only interaction analysis platform which permits the researcher to use either
microwell plates for rapid screening/ranking, AND flow cells for data-rich
kinetic characterizations, all on the same instrument/platform. Thirdly, SKi
Pro is modular and forward upgradable in the field, so it is possible to
start with your current needs, and add modules for upgraded features in the
future. Fourthly, SKi Pro is designed to be upgraded to higher throughputs
(either in wellplate or flow cell format). Please also see the "roadmap
question" below, Q21.
|
| Q2 |
I have evaluated / will evaluate an SPR instrument .
What benefits does Silicon Kinetics SKi Pro™ offer? |
| A2 |
a) SKi Pro offers plate reader capability, which
traditional SPR does not, b) SKi Pro has lower drift than SPR, 0.35 RU/h
compared to 18 RU/h in SPR, c) SKi Pro can be successfully used as a
front-end for mass spectrometers including for electrospray, whereas SPR
cannot, d) SKi Pro uses a less charged surface chemistry than SPR and as such
has lower non-specific binding, and e) SKi Pro is more economical than SPR
with respect to both the instrument and the consumables prices.
|
| Q3 |
How do results produced on Silicon Kinetics SKi Pro™
correlate with results obtained with other label-free methods? |
| A3 |
The 1nm of OPD change in SKi Pro instruments
corresponds to a response of about 50 RU in traditional SPR with Kretschmann
configuration of the prism. Silicon Kinetics has done benchmarking
experiments versus traditional SPR and has shown comparable kinetics
measurements at SPR limits. For complete comparisons, please see Application
Note 7 Benchmarking Nanopore Optical Interferometry (NPOI) Against SPR.
|
| Q4 |
I have evaluated / will evaluate another instrument
using optical interferometry as the detection method. What benefits does
Silicon Kinetics SKi Pro™ offer? |
| A4 |
a) SKi Pro offers flow cell capability in addition
to plate reading on the same instrument, which is not possible with other
optical interferometry methods, b) SKi Pro has 4-6x advantage versus planar
interferometry methods in LOD (limit of detection), c) analytes captured on 3D
surfaces of SKi Sensors can be eluted to a mass spec instrument for
identification.
|
| Q5 |
What applications are best suited for the Silicon
Kinetics SKi Pro™ platform? |
| A5 |
SKi Pro is suitable for standard applications such
as affinity ranking and kinetic characterization of binding of biomolecules:
protein-protein, protein-peptide, peptide-peptide, protein-DNA, at or better
than the LOD (limit of detection) of other label-free methods. In addition,
SKi Pro is designed to match the performance of specialty instruments for
solution-based measurement of very slow koff, all on one instrument. A specialty application is AC-MS
(affinity capture-mass spec), combining the sensitivity of label-free NPOI
(nanopore optical interferometry) with the information richness of mass
spectroscopy.
|
| Q6 |
What are the potential benefits of the dual-format
capability of SKi Pro™ system? |
| A6 |
For small biotech labs and academic/research
institutions, SKi Pro dual-format (plate reader and flow cell, on the same
instrument) permits rapid screening AND in-depth characterization in one
economical instrument, rather than two instruments using different detection
technologies/protocols. In addition, for mid-to-large size labs and
companies, SKi Pro dual-format allows similar chemistries/protocols across
labs, even when one instrument is reserved for ranking and another for
in-depth characterization, and perhaps another for immunogenicity profiling.
|
| Q7 |
What is needed to switch the instrument from the
plate-reader format to flow-cell format? |
| A7 |
Only the simple replacement of the wellplate holder
with the flow cell holder, done in seconds. All other adjustments (optical
alingment, etc.) are automatic.
|
| Q8 |
Can I obtain kinetics data with the plate-reader
format? |
| A8 |
Best kinetic data (kon, koff) are obtained in the flow cell format, as continuous flow
replenishes the analyte concentration decreased due to binding to the ligand.
Plate readers are best for bind/no-bind and affinity ranking experiments.
|
| Q9 |
Anything unique about surface coating of SKi Sensor™
biosensors? |
| A9 |
3D surfaces of SKi Sensor biosensors are first
coated with hydrophillic PEG linkers to allow lower NSB (non-specific
binding) than many other surfaces. For receptor immobilization, in addition
to standard surfaces such as carboxyl, NTA-Ni, streptavidine, Protein A,
Protein G, A/G, unique benzaldehyde chips allow the researcher to skip the
surface activation step.
|
| Q10 |
How is NSB (non-specific binding) with SKi Sensor™
biochips? |
| A10 |
SKi Sensors have been used successfully in 40% Rat
Serum (Latterich and Corbeil 2008, Proteome Science 6:31) and have shown low
non-specific binding in hybridoma supernatants as well. For more information,
please see the article "Label-free detection of biomolecular interactions in real time with a nano-porous silicon-based detection method".
|
| Q11 |
How does Silicon Kinetics benzaldehyde biosensor
offer advantages? |
| A11 |
Protein can be modified off-line with stoichiometric
amounts of linker, then directly conjugated to SKi Sensor surface. This saves
the activation step, which in turns allows higher throughput. For a full description, please see Application note 5.
|
| Q12 |
Are SKi Sensor biosensor chips re-generatable? |
| A12 |
Yes, all surfaces are re-generatable, as long as the
ligand molecule on the surface is stable to regeneration.
|
| Q13 |
How is NPOI (nano-pore optical interferometry)
different from SPR? |
| A13 |
a) In NPOI, light passes through many monolayers in
a 3D environment, increasing signal due to initial immobilization of ligand,
or the subsequent capture of analyte (versus a single monolayer in planar
surfaces in SPR), b) In NPOI, the unit of measure is a physical parameter:
optical path difference (OPD) in nanometers, which increases with binding,
and c) unlike SPR, NPOI does not require prisms, so the plate reader format
is more feasible and economical.
|
| Q14 |
How much sample do I need? |
| A14 |
Typically 1-5 µg of protein is immobilized in a flow
cell or on a well strip chip for the binding protein. For binding, 80-100 µL
per well is used for the plate reader whereas 10-120 µL are typically used in
the flow cell.
|
| Q15 |
SKi Sensors have 3D pores in silicon. Does that
introduce mass transport limitations? |
| A15 |
No. The 3D sensor surfaces have been tested for
diffusion of biomolecules into and out of pores in several ways, and
subsecond diffusion has been confirmed. For example, temporal OPD (optical path
difference) change has been measured with two solutions: low viscosity sugar,
and high viscosity BSA solution with large molecules (Figure Q14.1 below).
Both show similar, rapid OPD shifts, whereas diffusion limitations would have
shown up as slowly rising OPD shifts, rather than sharp increases. Silicon Kinetics has also tested on-rates on planar silica and compared results to those measured in 3D porous silicon. The results were comparable, confirming no mass transport limitation at appropriate flow rates.
SPR surfaces have been discussed with respect to a dense planar biosensor
surface rapidly depleting the analyte bulk concentration above the gold
surface. |
| |
 |
| |
Figure Q14.1: OPD (Optical Path
Diffference) increase with low-viscosity sugar solution diffusing into the
pores of SKi Sensors, compared with OPD shift due to diffusion of large BSA
molecules. In both cases, the diffusion is fast, as evidenced by sharp OPD
increases. |
| Q16 |
At what temperatures can the samples be stored? |
| A16 |
SKi Pro allows sample storage in its companion SKi
Prep from 4-10 deg C, or at room temperature.
|
| Q17 |
At what temperatures can the biomolecular
interactions be carried out? |
| A17 |
The SKi Pro instrument has a much wider range of
temperature capability for measuring real-time interactions than
most other platforms, making it ideal for complex thermodynamic measurements. This range is 10 deg C below ambient to 60 deg C.
|
| Q18 |
Does Silicon Kinetics auto-sampler have a
metal-free path? |
| A18 |
Yes, Silicon Kinetics auto-sampler (SKi AutoPrep) is
made specially for proteomics applications, and all paths are metal-free.
|
| Q19 |
What models of the SKi Pro™ system are available
now? |
| A19 |
All SKi Pro™ models are available. The new SKi Pro X1000 offers a superior
combination of sensitive plate reader and ultra-sensitive flow cell. X1000
plate reader features 8 optical heads, reading 8 wells at a time.
|
| Q20 |
What is the throughput for SKi Pro™? |
| A20 |
Throughput depends quite significantly on
application. As some examples: a 96 well plate of hybridoma supernatants
characterized by off-rate screening could take 2 hours. For flow cell
applications (for instance, for sensorgram measurements) up to 750 unattended
samples may be measured.
|
| Q21 |
What is the roadmap for the SKi Pro™ platform? |
| A21 |
SKi Pro platform is designed to be forward
upgradeable. Future upgrades will include a 24-flow cell version, in
increments of 6 flow cells, each self-referenced.
|
| Q22 |
How exactly is the SKi Pro™ platform "forward
upgreadable"? |
| A22 |
As upgrades are needed (more automation, moving from
single-format to dual-format capability), a service technician installs the
requisite modular element to your system.
|
| Q23 |
Do you have peer-reviewed publications? |
| A23 |
Yes. Please see under Publications
|
| Q24 |
What data are available for AC-MS (affinity
capture-mass spec) application? |
| A24 |
AC-MS may be used in a variety of applications. To
date, SKi Pro has been used in-line with electrospray application for small
molecule screening, and has been used in off-line applications for protein
capture and identification. |
| |
If you have more questions, please contact us |
| |
|
| SALES / SUPPORT / SERVICE |
| Q1 |
Does Silicon Kinetics offer leasing/renting options
for the SKi Pro™ instruments? |
| A1 |
Yes, both options are available. Please click here to enquire.
|
| Q2 |
What kind of warranty does Silicon Kinetics offer? |
| A2 |
Silicon Kinetics offers a standard one-year warranty.
|
| Q3 |
Does Silicon Kinetics offer maintenance contracts? |
| A3 |
Yes. Instrument price covers the first year of
maintenance. Additional multi-year maintenance contracts are offered.
|
| Q4 |
How do SKi Pro™ prices compare to others’ prices? |
| A4 |
SKi Pro is designed to be more capable, more
versatile AND more economical than others. In addition, our modular
arrangement allows the researcher to build up the most complete, automated
system one module at a time.
|
| Q5 |
What support is available to SKi Pro™ customers? |
| A5 |
Silicon Kinetics support includes: PhD-level
application scientists, feasibility testing in Silicon Kinetics labs, phone
support, and field service, among others.
|
| Q6 |
How quickly can I get a SKi Pro™ instrument
delivered? |
| A6 |
Standard delivery is 30 days ARO (after receipt of
order). Faster delivery may be possible .
|
| Q7 |
Does Silicon Kinetics offer installation service and
training for SKi Pro™ platform? |
| A7 |
Yes, SKi Pro instrument price includes installation at your
site and training.
|
| Q8 |
What consumables does Silicon Kinetics offer? |
| A8 |
Silicon Kinetics offers a range of SKi Sensor
biochips, as well as reagent kits, such as those for amino coupling, antibody
coupling and biotinylation. Please contact us at by clicking here.
|
| Q9 |
Can I talk to other Silicon Kinetics customers/users
for reference? |
| A9 |
Yes, certain customers and users have agreed to take
reference calls, and we would be pleased to connect you with them, after
understanding your needs and applications.
|
| Q10 |
How do I know Silicon Kinetics is a stable industry
player? |
| A10 |
Silicon Kinetics is fully funded as a privately-held
company. In addition, a majority shareholder of Silicon Kinetics is Trex
Enterprises, a privately held company which has operated successfully and
profitably since 1985.
|
| Q11 |
Does Silicon Kinetics offer contract services? Can I
get my experiments performed by Silicon Kinetics scientists for a fee? |
| A11 |
Yes, Silicon Kinetics does offer fee-based contract
services. These services include measurement of kinetic parameters, kinetic
characterization, affinity determination, special protocol development, among
others. These services are for epitope identification, mutant screening and
others.
Please click here to inquire.
|
| Q12 |
Can I buy Silicon Kinetics products with a credit
card? |
| A12 |
Yes, we offer purchases with a Visa card.
|
| Q13 |
Do you have an early access program for your
instrument/biosensor enhancements and new application development? |
| A13 |
Yes, we do work with early access partners on
enhancements and new applications.
|
| Q14 |
Is Silicon Kinetics offering SKi Pro™ outside North
America? |
| A14 |
Currently, Silicon Kinetics is offering full support
in North America only, but we are pleased to discuss needs outside North
America. |
| |
If you have more questions, please contact us |
