Execute event by changing text field focus

I have a text field inside a column of my GridView with the following code:

<asp:TemplateField HeaderText="Teste">
    <ItemTemplate>
        <asp:TextBox ID="txtTeste" runat="server" Width="100px" Text='<%#Eval("TESTE", "{0:n3}") %>' Enabled="true" OnTextChanged="txtQuantidade_TextChanged"></asp:TextBox>
    </ItemTemplate>
</asp:TemplateField>

I created the event OnTextChanged="txtQuantidade_TextChanged" that when typing something or changing the focus of the field a routine is executed inside the event

protected void txtTeste_TextChanged(object sender, EventArgs e)
{

}

Because this event is not triggered at any time, am I doing something wrong?

Thank you in advance.