The invention relates to a device for the mixing, homogenizing, extraction, or slurrying of materials, in particular infectious, or malodorous or chemically-aggressive materials in a laboratory test vessel which may be hermetically sealed with a lid. Conjugation through this position results in spectral properties that are uniformly superior to those of conjugates of spectrally similar dyes wherein attachment is at a different position. Under low-power, low-speed light loading conditions the system operates in a series hybrid driving configuration to avoid low efficiency and high pollution by the engine.