<?php

$string = <<<DATA
$50 From here i need only 50
$60.59 From here i need only 60, Need to remove $ and .59
€360 From here i need only 360.
€36.99 From here i need only 36 need to remove € and .99.
£900 From here i need only 900.
£90.99 From here i need only 90.
DATA;

$regex = '~[$€£]\K\d+~';

preg_match_all($regex, $string, $amounts);
print_r($amounts);

?>