{HEAD ~ The method} 9 wherein said {TAIL ~ optically active metal ion} is incorporated into said bead by coprecipitation during said sol gel process 
wherein
{ HEAD ~ The method } 9 wherein said { TAIL ~ optically active metal ion } is incorporated into said bead by coprecipitation during said sol gel process
HEAD HEAD HEAD HEAD HEAD HEAD OTH REL OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH