Hydrogel Nanocomposite Towards Optical Sensing of Spermine in Biomedical and Real-Life Food Samples and Remediation of Toxic Dyes from Wastewater

Biswakarma, D and Dey, N and Bhattacharya, S (2023) Hydrogel Nanocomposite Towards Optical Sensing of Spermine in Biomedical and Real-Life Food Samples and Remediation of Toxic Dyes from Wastewater. In: Langmuir, 39 (33). 11610 -11620.

PDF lan_39-33_11491-11934_2023.pdf - Published Version Restricted to Registered users only Download (7MB) | Request a copy

Abstract

Nanocomposites such as graphene oxide (GO) have been incorporated into hydrogels to enhance conventional hydrogels’ properties and develop new functions. Unique and strong molecular interactions between GO and low molecular weight gelators allow the fabrication of various functional hydrogels suitable for different applications. In the present study, we report a stable and soft nanocomposite hydrogel comprising a pyrene-based chiral amphipath having an amino acid (l-phenylalanine) core with pendant oligo-oxyethylene hydrophilic chains and GO. The mechanical and viscoelastic properties of the nanocomposite hydrogel were thoroughly studied using various spectroscopic, microscopic, and mechanical techniques. Even without GO, native hydrogels could form a self-supported thermoreversible and thixotropic hydrogel composed of the fibrillar network. Unlike native hydrogels, the morphological investigation of nanocomposite gels shows the presence of cross-linked nanosheet-like structures. The combined effect of π-π stacking and H-bonding interactions is the driving force for the formation of such composite hydrogels. Moreover, the nanocomposite hydrogels possess significantly superior mechanical stiffness than the native hydrogels. Interestingly, the thixotropic properties observed with the parent gel were retained even in the presence of carbon nanomaterials (GO). The nanocomposite hydrogel could be employed in the optical sensing of a biogenic polyamine, spermine, resulting in a visible gel-to-sol transition. The superior electrostatic interaction between the GOs and spermine molecules might have led to the release of entrapped fluorogenic dyes from the hydrogel network and a turn-on emission response. The sensory system was employed to analyze spermine content in human urine samples and decomposed food items. A gel-coated paper strip was also developed for onsite detection of the spermine. The nanocomposite hydrogel was further utilized to remove toxic organic dyes such as methylene blue (MB) and rhodamine B (RhB) from the aqueous media. The nanocomposite hydrogel thus showed excellent dye removal capabilities and was also found to be recyclable. Calculations of different mechanical parameters suggest that the dye removal efficiency of the nanocomposite hydrogel was better for MB than for RhB.

Item Type:	Journal Article
Publication:	Langmuir
Publisher:	American Chemical Society
Additional Information:	The copyright for this article belongs to the American Chemical Society.
Keywords:	Amino acids; Aromatic compounds; Dyes; Graphene; Nanocomposites; Rhodium compounds; Sols; Stereochemistry; Viscoelasticity, Dye removal; Food samples; Graphene oxides; Hydrogel nanocomposites; Mechanical; Methylene Blue; Nanocomposite hydrogels; Optical sensing; Rhodamine-B; Toxic dyes, Hydrogels, coloring agent; graphene oxide; hydrogel; nanocomposite; nanogel; spermine, human; wastewater, Coloring Agents; Humans; Hydrogels; Nanocomposites; Nanogels; Spermine; Wastewater
Department/Centre:	Division of Chemical Sciences > Organic Chemistry Division of Chemical Sciences > Solid State & Structural Chemistry Unit
Date Deposited:	04 Nov 2023 08:49
Last Modified:	04 Nov 2023 08:49
URI:	https://eprints.iisc.ac.in/id/eprint/83100

Actions (login required)

View Item