title: Fluorescent silk cocoon creating fluorescent diatom using a "Water glass-fluorophore ferry".
abstract: Fluorophores are ubiquitous in nature. Naturally occurring fluorophores are exceptionally stable and have high quantum yield. Several natural systems have acquired fluorescent signature due to the presence of these fluorophores. Systematic attempt to harvest these fluorophores from natural systems could reap rich commercial benefit to bio-imaging industry. Silk cocoon biomaterial is one such example of natural system, which has acquired a fluorescent signature. The objective of this study is to develop simple, rapid, commercially viable technique to isolate silk cocoon membrane fluorophores and exploring the possibility of using them as fluorescent dye in bio-imaging. Here, we report an innovative water glass (Na2SiO3) based strategy to isolate the silk cocoon fluorophores. Isolated fluorophore is majorly quercetin derivatives and exhibited remarkable photo- and heat stability. Fluorescence and mass spectrometric analysis confirmed presence of a quercetin derivative. We further used this fluorophore to successfully label the silicate shell of diatom species Nitzschia palea.
authors.affiliation: Bio-electricity, Green Energy, Physiology & Sensor Group', Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, 208016, India.
authors.forename: Tejas S
authors.initials: TS
authors.lastname: Kusurkar
authors.forename: Ishita
authors.initials: I
authors.lastname: Tandon
authors.forename: Niroj Kumar
authors.initials: NK
authors.lastname: Sethy
authors.forename: Kalpana
authors.initials: K
authors.lastname: Bhargava
authors.forename: Sabyasachi
authors.initials: S
authors.lastname: Sarkar
authors.forename: Sushil Kumar
authors.initials: SK
authors.lastname: Singh
authors.forename: Mainak
authors.initials: M
authors.lastname: Das
mesh_terms: D000818:Animals; D012831:Bombyx / Q000254:growth & development; D017377:Diatoms / Q000737:chemistry* / Q000378:metabolism; D036681:Fluorescence Recovery After Photobleaching; D005456:Fluorescent Dyes / Q000737:chemistry / Q000378:metabolism*; D007814:Larva / Q000378:metabolism; D008856:Microscopy, Fluorescence; D011794:Quercetin / Q000737:chemistry / Q000378:metabolism; D017640:Silicates / Q000737:chemistry*; D047011:Silk / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D014466:Ultraviolet Rays
chemical_list: D005456:Fluorescent Dyes; D017640:Silicates; D047011:Silk; D011794:Quercetin; C005691:sodium silicate