how to convert date and time from array to utc time and date/"2018-08-09T16:00:00.000Z"

i tried this code to convert but its not working.

var date = new Date(parseInt(crmDate.replace("/Date(", "").replace(")/", ""), 10));
date = date.toISOString();
return date;

does anyone knows how to convert the time and date from an array to utc time and date "2018-08-09T16:00:00.000Z"