1. Department of Chemical Sciences, Faculty of Science and Technology , Universiti Kebangsaan Malaysia , 43600 Bangi , Selangor , Malaysia
2. Department of Science and Technology, Faculty of Humanities, Management and Science , Universiti Putra Malaysia , 97008 Bintulu , Sarawak , Malaysia
3. Institut Ekosains Borneo , Universiti Putra Malaysia , 97008 Bintulu , Sarawak , Malaysia
4. Department of Chemistry, Faculty of Science , Universiti Putra Malaysia , 43400 Serdang , Selangor , Malaysia