It looks to me like you're trying to parse Text from Comma Separated Values. Hmm...I wonder if anyone's ever done this before?? Hmm... CPAN might be a good place to start looking... Wha? What's this? ...Text::CSV! Eureka, you're not the first person to have such a need! (I'm teasing, of course).

Here's an example straight from the Text::CSV POD:

use Text::CSV;

$csv = Text::CSV->new();              # create a new object

$status = $csv->parse($line);         # parse a CSV string into fields
@columns = $csv->fields();            # get the parsed fields
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Don't use a regex to do what can be done more reliably with a tried and proven module. Text::CSV is the right tool for the job. You'll find it even properly handles commas embeded in quoted strings.