how add fa-fa icon in checkbox but it must appears at the end

suppose to have a dropdown menu and I want that when I clinck on the menu I see the checkbox, the label and at the end the fa-fa icon.This is my jquery code when I put the checkbox on the menu:

$('#ul_menu').append('<li><input type="checkbox" name="aggiungi' + user_bookmarked[i].nome_bookmarked + '">     ' + user_bookmarked[i].nome_bookmarked + '<i class="fa fa-lock fa-1" aria-hidden="true"></i></li>');

I see the "fa fa-lock" attached to the checkbox label I want to appears at the end of the menu. Anyone can help me?

THIS IS MY HTML CODE:

div class="btn-group open"><button id="bookmarked_button" class="btn btn-default dropdown-toggle" data-toggle="dropdown" aria-expanded="true" type="button"><span class="visible-sm-inline visible-md-inline visible-lg-inline">Bookmarked</span><span class="caret"></span></button><ul class="dropdown-menu dropdown-menu-right" id="ul_menu"><li><input type="checkbox" name="aggiungidsfsdf" checked="">        dsfsdf</li><li><input type="checkbox" name="aggiungiasdas">     asdas<i class="fa fa-lock fa-1" aria-hidden="true"></i></li><li><input type="checkbox" name="aggiungicollaborativo">        collaborativo<i class="fa fa-lock fa-1" aria-hidden="true"></i></li><li><a href="#" id="aggiungi_bookmarked"><i class="fa fa-fw fa fa-plus"></i>Aggiungi Bookmarked</a></li></ul></div>