%% 
%%  Ein Beispiel der DANTE-Edition
%%  
%%  1. Auflage
%% 
%% 
%%  Copyright (C) 2013 Herbert Voss
%% 
%%  It may be distributed and/or modified under the conditions
%%  of the LaTeX Project Public License, either version 1.3
%%  of this license or (at your option) any later version.
%% 
%%  See http://www.latex-project.org/lppl.txt for details.
%% 
%% 
%% ==== 
% Show page(s) 1
%% 
%% 
\documentclass[]{exaarticle}
\pagestyle{empty}
\setlength\textwidth{352.81416pt}
\setlength\parindent{0pt}
%StartShownPreambleCommands
\usepackage{luacode,libertine}
\begin{luacode}
function checknode(List)
  for t in node.traverse(List) do
    if t.id==0 or t.id==1 then checknode(t.head) end
    if t.id==37 then
--      tex.print(unicode.utf8.char(t.char))
      if (t.char>96 and t.char<122) or
         t.char==228 or t.char==246 or t.char==252 then t.char=t.char-32 end
    end
  end
return true
end
\end{luacode}
\def\MUC#1{\setbox0=\hbox{#1}\directlua{checknode(tex.box[0].head)}\box0}
%StopShownPreambleCommands
\begin{document}
\MUC{Freie Universität Berlin}
\def\TU{Technische Universität Berlin}\MUC{\TU}
\MUC{ÄÖÜäöüß}%196 214 220 228 246 252 223
\end{document}