TWISTER is a universal and compact mixing device with magnetic drive. In the TWISTER SET 1, one drive is included.

In the default version, TWISTER is a powerful single-position magnetic stirrer for mixing up to 5 liters at a maximum speed of 3000 rpm and a viscosity of up to 500 mPas.

By connecting additional TWISTER stirring units (available as accessories, ID no. 0020112621), TWISTER can be expanded to a multi-position magnetic stirrer with up to 30 stirring positions.* The stirring positions can be controlled either separately or simultaneously (leader-follower principle).

Versatile accessories
With the multi-position stirring attachment TW.IX, the drive is transformed into a magnetic stirrer with 9 stirring positions for efficient mixing of sample vessels with small volumes (8 - 60 ml).
The TW.VX shaker attachment transforms the universal magnetic drive into a vortex or orbital shaker.

Innovative operating concept
TWISTER enables a new way of interaction between user and laboratory instrument. Via the intuitive and chemically resistant 360° LED glass display, all information is intuitively conveyed without any alpha-numeric display. During operation, either the speed or the power required for stirring can be displayed. For example, viscosity changes can be observed and displayed as a percentage.
Mixing can be started by pressing a button as well as (thanks to integrated beaker recognition) by placing or touching the beaker.
The reverse function changes the direction of rotation at definable time intervals. This leads to a significant improvement of the mixing result, especially with samples that are difficult to mix.

Robust and safe
The high protection class IP 66 allows operation under harsh conditions. TWISTER can thus be cleaned under the tap, for example, or operated in an incubator at temperatures up to 40°C.

What is Refractometry?

Refractometry - a long journey from Plato to Ernst Abbe
It was the philosopher Plato who first described an observation which was important for the subsequent understanding of the refractive index and the associated refraction law. He observed that oars have a normal appearance in the air, while they appear to have a kink under the water.
The first specific representation of the refraction of light was developed by the Persian mathematician and physicist Ibn Sahl in the 10th century. In a treatise on burning mirrors and burning glasses, he investigated the refraction of light and through this work is considered to be the discoverer of the refraction law.
However, his findings fell into oblivion and were not taken up again until six centuries later. Subsequently, the professor Willebrord Snell van Royen formulated a new version of the refraction law in 1621. His findings on the refraction of light at the interface of two transparent media with a different refractive index paved the way for the invention of the refractometer.
It was Ernst Abbe who subsequently presented his refractometer to the scientific community in 1872. It was built at the company Carl Zeiss in Jena. Abbe used refractometers for the examination of balsam and resin as well as for the immersion liquid required in the production of microscopes. His invention is still used today in the fields of education, research, industry and pharmacy.
Digital refractometers are frequently used today. They use LED light sources, prisms and CCD sensors. Digital multi-wavelength refractometers enable measurements at different wavelengths.