Nanobioscience

MSc Indian Institute of Technology Roorkee, Roorkee Department of Chemistry, India

PhD Indian Institute of Technology Bombay, Mumbai, Department of Chemistry

Mentor: Prof C P Rao, Specialization: Bio-Inorganic Chemistry

Post Doc (May 2009- Jan 2012): Dept. of Chemistry, Nanobioscience lab, Seoul National University, Seoul, South korea

Mentor: Prof Jwa-Min Nam Specialization: Nanobioscience

1. A process has been developed for immobilization of the chimeric enzyme, Smt3-d-psicose 3-epimerase, and production of nearly zero calorie sugar, D-psicose, from agro-industrial residues.(Patent File No. 201611044752)
2. Guanosine diphosphate (GDP) a promising natural small-molecule inhibitor that targets Hepcidin-FPN complex has been identified as an additional supplement to iron ameliorate AI.

1. Iron homeostasis, nutritional iron deficiency and common lifestyle diseases

• Hepcidin, a peptide hormone, is a key regulator in mammalian iron homeostasis. Increased level of hepcidin due to inflammatory conditions stimulates the ferroportin (FPN) transporter internalization, impairing the iron absorption; clinically manifested as anemia of inflammation (AI). Inhibiting hepcidin-mediated FPN degradation is proposed as an important strategy to combat AI. A systematic approach involving in silico, in vitro, ex vivo and in vivo studies is employed to identify hepcidin-binding agents. The virtual screening of 68,752 natural compounds via molecular docking resulted into identification of guanosine 5′-diphosphate (GDP) as a promising hepcidin-binding agent. The molecular dynamics simulations helped to identify the important hepcidin residues involved in stabilization of hepcidin-GDP complex. The results gave a preliminary indication that GDP may possibly inhibit the hepcidin-FPN interactions. 

2. Development of calorimetric nanobiosensor to detect food borne bacteria

3. Enzyme immobilization: Development of new type of nanoparticles to immobilize enzyme to make enzyme more robust and reusable

• Magnetite and magnetite core/shell (Fe₃O₄/SiO₂) nanoparticles were synthesized and functionalized with two different alkyl chain length linkers that were 3-Phosphonopropionic acid (3-PPA) and 16-Phosphonohexadecanoic acid (16-PHDA). Xylanase (EC 3.2.1.8, endo-1,4-xylanase, endo-1), was immobilized on as synthesized bare and silica coated magnetite nanoparticles via well-known EDC coupling. Transmission Electron Microscopy (TEM), Field Emission Scanning Electron Microscopy (FESEM), X-Ray Diffraction Spectroscopy (XRD), X-ray Photoelectron Spectroscopy (XPS), Dynamic Light Scattering (DLS) and Thermogravimetric analysis (TGA) techniques were utilized to characterize all the modifications. The flexible linker chain length plays a vital role in the catalytic attributes of the immobilized enzyme. Result shows that long chain alkyl linker grafted magnetite and magnetite core/silica shell nanoparticles exhibited a superior performance in terms of lower K_m, higher catalytic efficiency and better reusability. Furthermore, the immobilized xylanase shows improved tolerability performance at a wide range of pH and temperature. Silica-coated magnetite nanoparticles bound xylanase through 16-PHDA retained 90% of its initial activity after 10 consecutive cycles, further emphasize on the beneficial effect of linker chain length and inert silica coating.

1. Singhal NK1, Ramanujam B, Mariappanadar V, Rao CP. Carbohydrate-based switch-on molecular sensor for Cu(II)in buffer absorption and fluorescence study ofthe selective recognition of Cu(II) ions by galactosyl derivatives in HEPES buffer Org Lett. 2006 Aug 3;8(16):3525-8. (Impact factor (IF): 6.732). 

2. Angmo S, Tripathi N, Abbat S, Sharma S, Singh SS, Halder A, Yadav K, Shukla G, Sandhir R, Rishi V, Bharatam PV, Yadav H, Singhal NK*. Identification of Guanosine 5'-diphosphate as Potential Iron Mobilizer: Preventing the Hepcidin-Ferrportin interaction and Modulating the Interleukin-6/Stat-3 Pathway. Sci Rep. 2017 Jan 5;7:40097. doi: 10.1038/srep40097. (Impact factor (IF): 5.228).

3. Singh V, Rakshit K, Rathee S, Angmo S, Kaushal S, Garg P, Chung JH, Sandhir R, Sangwan RS, Singhal N*. Metallic/bimetallic magnetic nanoparticle functionalization for immobilization of α-amylase for enhanced reusability in bio-catalytic processes. Bioresour Technol. 2016 Aug;214:528-33. doi: 10.1016/j.biortech.2016.05.002. (Impact factor (IF): 4.917).

4. Singhal NK, Mitra A, Rajsekhar G, Shaikh MM, Kumar S, Guionneau P, Rao CP. Role of the orientation of -OH groups in the sensitivity and selectivity of the interaction of M(2+) with ribosyl- and galactosyl-imino-conjugates. Dalton Trans. 2009 Oct 21;(39):8432-42. doi: 10.1039/b903668g. (Impact factor (IF): 4.177).

1. Recipient of Fulbright-Nehru Academic and professional Excellence Fellowship
2. Best Paper Award from IIT Bombay
3. Brain Pool Post doctoral research fellowship