Add 01 instead of 1 to a string?

How can i add  01 instead of 1 in a string.
I've got a timer that counts from 1 to 24, but also i would like that he starts with 01.
But how can i change that?
Right now i use this code:
drpMinutes.Items.Add(new ListItem(count.ToString())); 


So count is the counter, and i would like to add it to a dropdownbox.
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