The patch clamp technique opened a new field in biological research and shed light on membrane permittivity for ionic currents. The key element in patch clamp measurements is the detection of the ionic currents in a single biological channel. It is known that the channels open and close at random times, thus modulating the ionic currents. The measured current switches between two levels corresponding to the open and close states of the channel. Determining the statistics of the open and closed periods is of crucial importance to the experimenter, because it reflects the response of channel protein to drugs and other factors. The detected signal is strongly corrupted by instrumentation and other noises, rendering the detection of the opening and closing moments extremely difficult. We describe the use of the wavelet transform and its associated multiresolution (multiscale) analysis to detect the currents through single ionic channels corrupted with noise.