How does the addition of shape distinct gold nanoparticles influence on the conformational transition of poly(N-isopropylacrylamide)?

• Published in: Journal of colloid and interface science Vol. 582; no. Pt B; pp. 478 - 487
• Main Authors: Yadav, Ritu, Kumar, Sumit, Narang, Payal, Venkatesu, Pannuru
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 15.01.2021
• Subjects: Au nanospheres/nanorods; biomedical research; body temperature; Differential scanning calorimetry; Drug delivery; fluorescence emission spectroscopy; Fourier transform infrared spectroscopy; gold; humans; Lower critical solution temperature; nanogold; nanorods; nanospheres; Poly(N-isopropylacrylamide); polymers; surface area; transmission electron microscopy; Differential scanning calorimetry; dH; Poly(N-isopropylacrylamide); Au nanospheres/nanorods; AuNPs; Drug delivery; LCST; Lower critical solution temperature; pNIPAM
• ISSN: 0021-9797; 1095-7103; 1095-7103
• DOI: 10.1016/j.jcis.2020.08.074

[Display omitted] •Au nanospheres/nanorods were synthesized to monitor the LCST of PNIPAM.•Au nanospheres/nanorods were characterized by using UV, DLS and TEM.•Increase in LCST of PNIPAM was observed with Au nanoparticles.•DSC was employed to study LCST of PNIPAM in various concentrations of AuNPs.•To study morphological changes TEM was assessed. The subject of nanomaterials has created immense interest and expectations in the field of science and nanotechnology. Plentiful aspects proposed by gold nanoparticles (AuNPs) and their capability to affect macromolecular transition is the main driving force to execute the current study. A thermo-responsive polymer poly(N-isopropylacrylamide) (pNIPAM) is studied in presence of nanoparticles, particularly gold nanorods and nanospheres to elucidate completely the effect of their shape, surface area and structural morphology on the conformation of pNIPAM. In this respect, several biophysical techniques such as fluorescence spectroscopy, dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) are utilized to examine the interaction of Au nanospheres/nanorods with pNIPAM. For a better understanding of Au nanoparticles morphology, transmission electron microscopy (TEM) is also employed. Introducing gold nanoparticles with the polymeric solution promotes the polymer to stay in the coil conformation at a higher temperature than the LCST of aqueous pNIPAM. A shift of 2 and 25.5 °C in the LCST of pNIPAM is observed along with Au nanospheres and nanorods, respectively. The current study provides a better impact in the field of biomedical science specifically drug delivery and tissue engineering as the LCST approaches human body temperature.