Temperature dependent micellization behavior of as synthesized anionic SAILs in aqueous nonionic polymer solutions: conductivity, UV-visible probe and antimicrobial studies

Abstract

As synthesized surface active ionic liquids (SAILs), Tetrapropylammonium Dodecylsulfate (TPADS), and Tetrabutylammonium Dodecylsulfate (TBADS) have been characterized by FTIR, ¹H-NMR and ¹³C-NMR spectroscopic techniques. Conductometric and UV-Visible probe investigations have been attempted to study the aggregation behavior of these synthesized SAILs in aqueous solution of polymers Polyvinylpyrrolidone (PVP) and Polyethylene glycol (PEG) at different temperatures and concentrations. Two breaking points were identified from κ vs [SAILs] plots. First, the critical aggregation concentration (CAC) is recognized with the polymer-SAILs binding and the second being regarded as critical micellar concentration (CMC), suggested to represent saturation point for Polymer-SAIL aggregation. Thermodynamic parameters of micellization $(\Delta G_m^o,\Delta H_m^o \mathit{\text{and}}\Delta S_m^o)$ are rationalized in terms of interactions prevailing between hydrophobic and hydrophilic regions of SAIL-Polymer system. Micellization process for the blend of SAIL-PVP is found to be more favored than SAIL-PEG at all temperatures. Further, the effect of PVP on the antimicrobial activities of TPADS/TBADS has been tested by measuring zone of inhibition which accounts for higher effectiveness of PVP-SAILs system against gram positive bacteria (Bacillus cereus and Staphylococcus aureus) as compared to gram negative bacteria (Pseudomonas aeruginosa).

GRAPHICAL ABSTRACT

Keywords:

• Surface active ionic liquid
• nonionic polymers
• aggregation
• bacteria
• zone of Inhibition

Acknowledgments

Manish thanks UGC, New Delhi for the award of Junior Research Fellowship and Senior Research Fellowship (F. No. 16-9(June 2018)/2019(NET/CSIR) dated 17.04.2021). Financial support from UGC-SAP (DRS-I, II and III) [No. F.540/3/DRS/2010(SAP-1) and F.540/2/DRS-II/2018(SAP-I)] to the Department of Chemsitry, HPU Shimla is also acknowleged. Authors thank Department of Biotechnology, HPU Shimla and AMRC IIT Mandi for conducting microbial studies and characterization of SAILs, respectively.

Correction Statement

This article has been corrected with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This study was supported by University Grants Commission.