Product Screencast on the NANOSENSORS™ uniqprobe AFM Probes series by product developer Dr. Laure Aeschimann.
For applications in biology and life sciences, where soft cantilevers are needed, we developed a dedicated Product Series: the NANOSENSORS uniqprobe.
The two main advantages of the uniqprobe cantilevers, which makes them unique for measuring on soft samples without drift, are first the uniformity of the cantilever thickness and second the partial gold reflective coating as explained later.
The outstanding uniformity of the uniqprobe cantilever thickness provides the possibility of realizing very soft cantilevers and leads to a strongly reduced dispersion of force constants and resonance frequencies compared with standard silicon probes.
The force constant of a cantilever is proportional to the power of three of its thickness. This means that by reducing the variations of the cantilever thickness (from typically +/-500nm for silicon cantilevers to +/-30nm for uniqprobe cantilevers) we could reduce significantly the variations of the force constant and of the resonance frequency.
The uniformity of the mechanical characteristics of the uniqprobe AFM cantilevers is especially important for applications where a large number of probes with known and near identical force constants are needed. In order to collect reproducible data for quantitative measurements of nano-mechanical properties such as adhesion forces or elastic properties of living matter, accurate determination of the spring constant is essential. The probes of the uniqprobe series are especially adapted for molecular biology, biophysics and quantitative nano-mechanical studies as well as general purpose applications.
In contrast to conventionally coated AFM probes that employ a metal coating over the entire cantilever, the uniqprobe coating covers only a short region of the cantilever free end above where the tip is located.
While maintaining high optical reflection this partial coating permits to preserve the mechanical properties of the cantilevers. Further benefits of the uniqprobe coating are stress free cantilevers with less bending and reduced drift, especially when imaging in liquid environments.
The cantilevers and tips of the uniqprobes are made out of a quartz-like material.
The combination of the new mechanically stress free material with a novel fabrication technology leads to absolutely straight cantilevers, even if they are very long, thin and soft. The cantilever shown on the picture has a thickness of only 350nm for a length of 125um.
The tip of the uniqprobes have a circular symmetric shape as shown on the second image. The tip is typically 7um high and features a small tip radius typically smaller than 10nm.
The support chip of the uniqprobes has the same size as of standard AFM probes.
There are alignment grooves on the back side of the support chip which ensure replacement of the probes without major adjustment of the laser beam when used in conjunction with an alignment chip.
NANOSENSORS uniqprobes are available as several different cantilever types.
The uniqprobe Contact and Soft Contact types are AFM probes with a single rectangular shaped cantilever.
The low force constants of these two types permit contact mode measurements on soft biological materials in air or in liquids.
The uniqprobe BioAC type has three rectangular shaped cantilevers with different geometries. This multi-lever type is designed for various imaging applications in air and liquids for mainly dynamic mode AFM.
The uniqprobe BioAC type unites fairly high resonance frequencies with low force constants. The combination of these characteristics leads to stable, low noise and fast measurements with reduced tip-sample interaction.
The uniqprobe BioT type has 2 triangular shaped cantilevers with different geometries. This multi-lever type is designed for various applications in air or liquids. Both cantilevers can be used for measurements in contact mode or dynamic mode AFM.
Thank you for your interest and your attention!
You can download our uniqprobe brochure from nanosensors.com website.
If you have any questions, want to give feedback or need more information, please get in touch and contact us at info@nanosensors.com.