This laboratory centrifuge serves for the sedimentation of cells, biological components and molecules, among them nucleic acids and proteins after their isolation, and for the separation of heterogeneous mixtures under centrifugal force. It is used in the biology classrooms of general secondary education institutions for laboratory work, practical lessons and demonstrations, and for preparing biological specimens for microscopic examination. The centrifuge is operated by the teacher or the laboratory assistant, students do not work with it unsupervised, and the recommended age of learners is from 10 years, that is pupils of grade 5 and above.
The centrifuge is a desktop micro-format device with an electric drive and microprocessor control. The rotor has 6 sockets for tubes of 1.5 and 2.0 millilitres, the rotation frequency is adjusted from 500 to 4000 revolutions per minute with digital indication on the display, the maximum rotation frequency is 6000 revolutions per minute and the maximum relative centrifugal acceleration is 2000 g. A timer allows the centrifugation time to be set, the digital display shows the rotation frequency and the running time, and the acceleration and stopping take a few seconds. The device has a mechanical lid with a catch, a safety on and off switch and a protection system against overload. The body is made of plastic and stands on non-slip feet, and power is taken from the mains with the parameters given on the rating plate. The centrifuge is installed on a laboratory table and is supplied assembled, needing no preliminary adjustment. Operating conditions are the premises of an educational institution at an air temperature from +5 to +40 °C and relative humidity from 40 to 60 % without condensate. Marking and operating documentation are in Ukrainian, the marking carries the trade mark, the model and a place for the inventory number, and the documentation comprises the passport with the warranty coupon and the operating instructions. The service life is 5 years and the warranty period is 12 months.
The set includes the laboratory centrifuge with the rotor installed — 1 pc; a rotor for 6 tubes of 1.5 and 2.0 ml — 1 pc; a set of tubes or adapters for standard tubes, depending on the configuration of delivery; a mains cord — 1 pc; the passport with the warranty coupon — 1 pc; and individual transport packaging — 1 pc, an individual corrugated cardboard box with the contents fixed inside. The exact composition of the set is stated in the packing list and in the passport of the device, and the factory packaging is kept for later transport and storage.
The centrifuge is placed on a firm, level, horizontal laboratory table able to take vibration, with enough space around and above it for the lid to open fully and for free air circulation, away from heating devices, damp places and the edge of the table, and with the ventilation openings unobstructed. The mains parameters are checked against the rating plate and the cord is plugged into an earthed socket, after which the display shows the frequency and the time. Before work the rotor chamber is inspected and is clean, without water, glass fragments or residues, the rotor is checked to turn freely by hand and to be firmly fixed without knocking or noticeable run-out, and only intact tubes of the type and volume intended for the rotor, 1.5 and 2.0 ml, are filled to the required level and closed tightly. Balancing the rotor is the most important operation, since an unbalanced rotor causes strong vibration, noise, movement of the device across the table and damage to internal parts: the tubes are placed symmetrically opposite one another, each pair has the same mass together with its contents, an odd sample is balanced with a counterweight tube of the same kind filled with water, and all tubes in the rotor are of one type with identical caps. The balanced tubes are then loaded, the lid is closed until it latches, the power is switched on, the rotation frequency and the centrifugation time are set with the buttons on the control panel and the start button is pressed; the first seconds of the run are watched, and if strong vibration, knocking, grinding or movement of the device appears the stop button is pressed immediately. After the timer has run out the rotor stops automatically, and only after it has stopped completely is the lid opened, the tubes taken out without shaking so that the sediment is not stirred up, and the supernatant liquid removed with a pipette or poured off carefully while the sediment is held back.
The lid is never opened while the rotor is turning, which is the main safety rule for work with a centrifuge, and the device is not started with the lid open or unlatched, with the rotor removed or if the lid does not latch. The rotor is not braked by hand or with objects, nothing is inserted into the rotor chamber while it turns, the protective covers are not removed, and the running device is not left unattended, moved or tilted. Flammable, volatile, caustic and explosive liquids and compounds are not centrifuged, cracked, deformed or melted tubes and tubes of a type not intended for this rotor are not used, and the rated mass of one tube with its contents given in the rotor passport is not exceeded. The device is not used with a damaged cord or plug and is disconnected from the mains before cleaning and servicing. After each work the rotor chamber and the rotor are wiped with a cloth moistened in a weak detergent solution and then dried; if a tube has broken, the fragments are removed with tweezers and the rotor sockets are washed thoroughly and disinfected. Water is not poured into the chamber or onto the body, the device is not immersed in liquid and abrasive powders, solvents and acetone are not used. Once a month the ease of rotation of the rotor by hand, the reliability of its fixing, the cleanliness of the ventilation openings and the condition of the mains cord are checked; repairs of the electrical part and the drive are made only by an authorised service centre.
