May be something like this: 

$a = "a10, b10, C10";

$a =~ s/([a-z])([0-9]+)/\u\1\:\2/g;

print "$a\n";

[download]

UPDATE: Already shown by other monks!

In reply to Re: How would I change a10 into A:10 in perl? by umasuresh
in thread How would I change a10 into A:10 in perl? by Tails

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