See the documentation for the Signal Processing Toolbox function designfilt, partucularly the ‘Examples’ section ‘Bandpass IIR Filter’. (The example looks like a Butterworth response, but it doesn’t say.) You can also start with buttord, then butter if you want a bit more control over the filter design.
If you don’t have access to the Signal Processing Toolbox, another site I’ve recommended in the past is Interactive Filter Design from the University of York (U.K.).
