ZnO nanoflower based sensitive nano-biosensor for amyloid detection

• Published in: Materials Science & Engineering C Vol. 78; pp. 960 - 968
• Main Authors: Akhtar, Najim, Metkar, Sanjay Kisan, Girigoswami, Agnishwar, Girigoswami, Koyeli
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.09.2017; Elsevier BV
• Subjects: Alzheimer's disease; Amyloid; Amyloid detection; Amyloidosis; Binding; Biosensing Techniques; Biosensors; Chemical compounds; Diabetes mellitus; Diabetes Mellitus, Type 2; Dyes; Fluorescence; Fluorophores; Humans; Insulin; Insulin amyloid; Materials science; Nanoparticles; Nanostructures; Neurodegenerative diseases; Neurological diseases; Optical properties; Photobleaching; Resonance; Silver; Substrates; Thin film coatings; Zinc; Zinc Oxide; Zinc oxides; ZnO nanoflower; β-Amyloid; ZnO nanoflower; Amyloidosis; Amyloid detection; Insulin amyloid
• ISSN: 0928-4931; 1873-0191
• DOI: 10.1016/j.msec.2017.04.118

Zinc oxide (ZnO) is a semiconductor metal oxide nanoparticle with inherent optical properties. Among the different zinc oxide nanostructures, nanoflowers have greater surface area. Utilizing this property a reagentless biosensor has been developed for the detection of beta amyloids, a hallmark of neurodegenerative diseases like Alzheimer's disease, Creutzfeldt-Jakob Syndrome, insulin dependent type II diabetes etc. The poor fluorescence quantum yield and photobleaching effect of Thioflavin T (ThT) upon binding to the model insulin amyloid beta sheets in solution can be overcome by the present engineered biosensor where ThT acts as a target as well as a reporter to detect amyloids adsorbed on a solid template based on ZnO nanoflower. ThT was adsorbed on ZnO NFs grown over nano-silver thin film coated glass slide. The in vivo imaging system was used to detect and quantify the fluorescence intensity generated from the substrates upon binding with insulin amyloid. ZnO NFs have the waveguiding property which increases the local field intensity caused by a resonance between the guided fundamental mode and evanescent field associated with high- order modes. This resonance phenomenon reinforces the excitation of the fluorophores in close proximity of the NFs thereby exhibiting enhanced fluorescence like Fabry Pero't Resonator (FPR). Considering the engineering and sensitivity, the reported nanobiosensor developed on ZnO nanoflower can be treated as faster and cost effective amyloid sensor. •Amyloids are responsible for different neurodegenerative diseases; its detection is important for early diagnosis.•Conventional methods are expensive and time consuming.•Present study demonstrates a ZnO nanoflower grown on nano Ag thin film based nanobiosensor for amyloid detection.