Regular Expressions CLR Not matching certain texts.

[foreveryoung]

I have created my first CLR in SQL to use regular expressions designed to match certain codes. Trouble is that I am trying to match the text HE1 in a string and keep getting a match for HE12 which is what I want to avoid. I have tried dbo.RegMatch(N'HE1[^0-9]' but this doesnot match anything. The vb.net is

Imports System
Imports System.Data
Imports System.Data.SqlClient
Imports System.Data.SqlTypes
Imports Microsoft.SqlServer.Server
Imports System.Text.RegularExpressions

Partial Public Class UserDefinedFunctions
    <Microsoft.SqlServer.Server.SqlFunction()> _
    Public Shared Function RegMatch(ByVal REGULAREXP As String, ByVal Comments As String) As Integer
        ' Add your code here
        Dim rx As New Regex(REGULAREXP, RegexOptions.IgnoreCase) ' Or RegexOptions.IgnorePatternWhitespace)

   If rx.Match(CType(Comments, String)).Success = True Then
            Return 1
        Else
            Return 0
        End If
   End Function

End Class