Impedance Biochip - HZDR Innovation

Dilution-free cell counting and cell monitoring

In order to determine the number of biological species such, e.g. of bacteria in a test liquid, complex methods such as microscopic counting of CFUs – usually by dilution – or optical density (OD) measurements- usually in the range 0.2 <OD <2.0 – are required. Using the newly developed impedance biochip PolCarr^® the number of cells in 10-30 µl test liquid can be determined fast, without dilution, and without illumination in a concentration range that corresponds to 0.05 <OD <16.00.

Patented technology for widespread use in the life sciences

The PolCarr^® impedance biochip stands for Polarizable Carrier. The PolCarr^® impedance biochip was developed for use on transparent and flexible silicon thin films. During the manufacture of PolCarr^® biochips, silicon is converted into a polarizable carrier material with surface-near, electrostatic gradient forces with a range of up to 200 nanometers by means of ion implantation. PolCarr^® is an innovative platform technology for counting cells and biomolecules in 10-30 µl test liquid. The test liquid is pipetted into the ring electrode, the cells and biomolecules are immobilized within the ring electrode of the PolCarr^® impedance biochip and the impedance of the PolCarr^® impedance biochip is measured.

In the manufacture of PolCarr® biochips, silicon is converted by ion implantation into a polarizable carrier material with near-surface electrostatic forces in a range of up to 200 nanometers (nm). The PolCarr® biochip was developed for use on transparent and flexible thin silicon films.

Patent: US 14 / 342,094

Functionality and areas of application

The PolCarr^® impedance biochip is connected to an impedance meter. The test liquid (10-30 µl) is pipetted into the ring electrode. The measured change in impedance of the PolCarr^® impedance biochip depends on the number and vitality of the cells in the test liquid and is modeled with a few parameters and calibrated with the number and vitality of the cells. This enables a sensitive determination of the cell concentration in a concentration range that corresponds to 0.05 <OD600 <16.00.

There are two types of PolCarr® biochips available:

Biochips with increased electrostatic attraction for negatively charged cells (Biochip BS)
Biochips with increased electrostatic attraction for positively charged cells (Biochip PS)

Benefits of the Biochip

Large dynamic range (0.05 < OD600 < 16.00)
Easy impedance calibration of biochip
Self-organized immobilization of polarizable cells and biomolecules
Fast and quasi-continuous measurement and analysis for in-situ control
High robustness of functionality against autoclaving, shock freezing, and incubation
Minimal use of liquid test material (10-30 μl)

What we offer

Order the impedance biochip PolCarr® according to your requirements:

Biochip BS for negatively charged cells (simple metal contacts or bonded)
Biochip PS for positively charged cells (simple metal contacts or bonded)

Please use the order form to place an order.

Order Form PolCarr Biochip (348.69 KB)

Latest Publication

The latest publication with the title „Functionalized silicon substrates with stripe-patterned surface-near electrostatic forces for the self-organized, stable immobilization of biomolecules“ is from April 2021.

Article in Applied Surface Science, April 2021

Contact for Requests

Dipl. Phys. Stephan Krüger

Phone: +49 351 260 2180

polcarr@hzdri.de