Your regular expression almost works, you just forgot to escape the period. Also, in PHP you need delimiters:
'/@(.*?)./s'
The s is the DOTALL modifier.
Here's a complete example of how you could use it in PHP:
$s = '[email protected]';
$matches = array();
$t = preg_match('/@(.*?)./s', $s, $matches);
print_r($matches[1]);
Output:
bar
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