title: Transformation of crystalline starch nanoparticles into highly luminescent carbon nanodots: Toxicity studies and their applications.
abstract: Being abundant in many tropical part of the world, Dioscorea sp. as food is limited due to its toxicity. However polysaccharides derive from these tubers could be important for other applications. Here we developed a Highly Luminescent Carbon Nanodots (C-dots) via acid hydrolysis of Gadong starch (GS). The hydrolysis rate of GS increased from 49% to 86% within 7 days while the X-ray diffraction showed the native GS particle is a C-crystalline type. The GS particles were either round or oval with diameters ranging from 50-90 nm. Further acid dehydration and surface oxidation reduced the size of GS nanoparticles to 6-25 nm. The C-dots produced a fluorescent emission at wavelength 441 nm. Toxicity tests demonstrate that zebrafish embryo were able to tolerate the C-dots for 48 h after exposure. This study has successfully demonstrated a novel approach of converting GS into excellent fluorescent C-dot.
authors.affiliation: School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, 43600 Selangor, Malaysia.
authors.forename: Regina Sisika A
authors.initials: RSA
authors.lastname: Sonthanasamy
authors.affiliation: School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, 43600 Selangor, Malaysia.
authors.forename: Wan Yaacob Wan
authors.initials: WYW
authors.lastname: Ahmad
authors.affiliation: School of Bioscience and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, 43600 Selangor, Malaysia.
authors.forename: Shazrul
authors.initials: S
authors.lastname: Fazry
authors.affiliation: School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, 43600 Selangor, Malaysia.
authors.forename: Nurul I
authors.initials: NI
authors.lastname: Hassan
authors.affiliation: School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, 43600 Selangor, Malaysia. Electronic address: azwanlazim@ukm.edu.my.
authors.forename: Azwan Mat
authors.initials: AM
authors.lastname: Lazim
mesh_terms: D000818:Animals; D002244:Carbon / Q000737:chemistry; D027742:Dioscorea / Q000737:chemistry*; D004625:Embryo, Nonmammalian / Q000187:drug effects; D049408:Luminescent Agents / Q000009:adverse effects / Q000138:chemical synthesis* / Q000737:chemistry; D045663:Quantum Dots / Q000737:chemistry*; D013213:Starch / Q000031:analogs & derivatives*; D015027:Zebrafish
chemical_list: D049408:Luminescent Agents; D002244:Carbon; D013213:Starch
keywords: Acid hydrolysis; Carbon dots; Dioscorea hispida; Nanocrystal; Starch