guest ::
| Home > Publications database > Introduction of New Rotational Mini-Rheometer for Scarce Sample |
| Home > Publications database > Introduction of New Rotational Mini-Rheometer for Scarce Sample |
| Conference Presentation (After Call) | FZJ-2025-05036 |
; ;
2025
Abstract: We introduce a miniaturized stress-controlled rheometer, aimed at enhancing rotational rheometry for analysis of scarce samples. This innovative device addresses the critical need for analyzing samples, such as biofilms, nascent drug formulations, and rare metal inks for microelectronics, which are typically limited in quantity due to their high production costs, challenging synthesis, or exclusive origins. Rheological measurements typically require at least 20 µl of sample material using commercial rotation rheometer, a requirement significantly reduced by our device, whereas the employed cone-plate geometry only requires 2 µl of sample material, representing a significant advancement in sample conservation. The mini-rheometer, approximately the size of a 50mm cube, utilizes an air bearing rotor made of quartz glass, manufactured via Selective Laser Etching (SLE). This subtractive 3D printing method for glass ensures the precision needed for an air bearing with µm-scale gaps. An outer magnetic field drives a centrally-placed magnet, while the angular displacement is accurately gauged by two Hall effect sensors, that detect the rotational movement of the inner magnet. The mini-rheometer´s efficiency and functionality were tested on calibration fluids, from water to viscous oils, as well as biological samples, such as percolating blood. This development extends the benefits of rotational rheometry – such as a wide range of strain rates and homogeneous strain profiles – to experiments where sample availability is limited. Due to the device´s miniaturized dimensions common, inverted microscopes can be used to study microstructural properties related to macroscopic flow behavior, which we used for the biological samples.
|
The record appears in these collections: |