title: The biological stimuli for governing the phase transition temperature of the "smart" polymer PNIPAM in water.
abstract: A lack of sufficient knowledge regarding the behaviour of stimuli-responsive polymers to biological stimuli hinders the potential use of responsive polymers as biomaterials and medical devices. Hence, in this study, we demonstrate the impact of various globular proteins on the phase transition temperature of poly(N-isopropylacrylamide) (PNIPAM) in an aqueous solution through the use of fluorescence spectroscopy, dynamic light scattering (DLS), Fourier transform infrared (FTIR) spectroscopy and field-emission scanning electron microscopy (FESEM). Furthermore, we describe the molecular interaction of PNIPAM with proteins by the MolDock method. Our experimental and docking studies revealed that such proteins as α-chymotrypsin (CT), insulin (In) and haemoglobin (Hb) decreased the lower critical solution temperature (LCST) of the polymer, whereas succinyl-concanavalin A (SCA) increased the LCST of PNIPAM. The LCST changed upon increasing the concentration of protein from 0.5mg/mL to 1mg/mL. The thermoresponsive behaviour of PNIPAM can be significantly altered by the functional groups present in the protein. The findings of the present study can be used in the engineering of bioresponsive smart PNIPAM-based devices.
authors: Department of Chemistry, University of Delhi, Delhi 110 007, India.
authors: Reddicherla
authors: R
authors: Umapathi
authors: Department of Chemistry, University of Delhi, Delhi 110 007, India; Department of Chemical Engineering, Feng Chia University, Taichung 40724, Taiwan.
authors: P Madhusudhana
authors: PM
authors: Reddy
authors: Department of Chemistry, University of Delhi, Delhi 110 007, India.
authors: Awanish
authors: A
authors: Kumar
authors: Department of Chemistry, University of Delhi, Delhi 110 007, India. Electronic address: pvenkatesu@chemistry.du.ac.in.
authors: Pannuru
authors: P
authors: Venkatesu
authors: Department of Chemical Engineering, Feng Chia University, Taichung 40724, Taiwan.
authors: Chi-Jung
authors: CJ
authors: Chang
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D008958:Models, Molecular; D062105:Molecular Docking Simulation; D044367:Phase Transition; D011506:Proteins / Q000737:chemistry; D044366:Transition Temperature; D014867:Water / Q000737:chemistry
chemical_list: D000180:Acrylic Resins; D011506:Proteins; D014867:Water; C052970:poly-N-isopropylacrylamide
keywords: Biophysical methods; MolDock method; Molecular interaction; Poly(N-isopropylacrylamide); Proteins