cavity 18 defined by the interior of the hollow oscillating element 12 in use a filter holder 50 is mounted to the free end of the oscillating element 12 the filter holder 50 provides a fixture for positioning a replaceable filter 52 so that the fluid that is drawn into the oscillating element 12 passes through the filter 52 as the fluid is drawn through the filter particulate matter 54 in the fluid becomes trapped in or on the filter 52 it is the measurement mass of the particulate matter 54 trapped by filter that is the purpose of the microbalance 10 it can be appreciated that the filter 52 must be firmly affixed to filter holder 50 to prevent the filter 52 from moving relatively to the filter holder 50 this can be accomplished by securing the two elements together with any appropriate securing means e g glue epoxy or ultrasonic welding compatible with the specific application fig5 to 8 show enlarged views of exemplary alternative configurations of the resistive element 16 fig5 shows a mechanically or electrochemically deposited resistive element 16 with an insulating material 17 the resistive element 16 can be applied using chemical vapor deposition or any suitable plating process appropriate for the selected materials of construction the insulating material 17 can be any suitable material but may for example be an ml epoxy applied by spraying or with a paint brush a pyralene pvd physical vapor deposition insulating material or a titanium carbo nitride layer deposited by chemical vapor deposition fig6 shows a mechanically wound resistive element 16 with insulating material 17 fig7 shows a resistive element 16 that is mechanically wound while the glass from which the oscillating element 12 is made is heated to the soft working temperature.