send hl7 using vb.net with mllp

i am trying to send hl7 using vb.net with mllp , can anybody tell me that is the wrong of my code

Dim StartBlock As String = "0x0b" ' this is start block

Dim EndBlock As String = " 0x0d" ' this is end Block

Dim ReturnBlock As String = "0x1c" ' this is return

Msg = StartBlock & Msg & EndBlock & ReturnBlock

Dim networkStream As NetworkStream = tcpClient.GetStream()

If networkStream.CanWrite And networkStream.CanRead Then

Dim sendBytes As [Byte]() = Encoding.ASCII.GetBytes(Msg)

networkStream.Write(sendBytes, 0, sendBytes.Length)

end if