Sixteenth notes are commonly used within a beat in conjunction with eighth notes. The following examples demonstrate the Blues scales of F and F# using common rhythmic figures. It is a good idea to practice all your scales and arpeggios using these rhythms.
This riff makes use of both of the above rhythm figures.
Here are four more important 16th note figures. Practice each one on one note as shown below and then use them to play arpeggios and scales. When you are confident with each rhythm, try improvising with it.