You need to break up the regex you have posted and explain your reasoning behind putting the constructs which are there in your regex. Also, instead of posting "sample data" for the pattern you can looking for, it would be much for helpful for your own sake to frame the requirements in words. An e.g. the regex should accept any two alphabets followed by a colon and one or more digits.
For Each ctrl As Control In Me.Controls("pnlMainPanel").Controls
If ctrl.GetType Is GetType(System.Windows.Forms.Panel) Then
For Each subCtrl As Control In ctrl.Controls
If subCtrl.GetType Is GetType(System.Windows.Forms.TextBox) Then
If subCtrl.GetType Is ...