Systems, devices and methods for evaluating a downhole fluid from a borehole intersecting an earth formation. The method may include filtering magnetic particles in the downhole fluid by activating a switchable magnetic filter when the downhole fluid enters a sample chamber in the borehole. The filter may include a wire mesh comprising strands of conductor oriented in a first direction; and strands of soft magnetic material oriented in a second direction. The method may also include cleaning the switchable magnetic filter by deactivating the switchable magnetic filter. Cleaning the switchable magnetic filter may include removing filtered particles using a fluid. The method may further include estimating a parameter of interest of the downhole fluid in the sample chamber.