An eco-friendly approach toward downstream processing of bacterial biomass for extraction of an intracellular potential bioplastic material polyhydroxyalkanoates replacing chlorinated organic solvents is reported using ionic liquid (IL)dissolved wet bacterial biomass of Halomonas hydrothermalis (MTCC accession no. 5445; NCBI Genbank accession no. GU938192), with ease on account of its high hydrogen bond basicity (β = 1.07). The recovered polymer with a yield of 60% ± 2% was characterized using 1 H NMR, FT-IR, and TGA techniques and confirmed to be polyhydroxybutyrate (PHB). The properties of PHB were found to be in close proximity to the standard PHB. The [C 2 mim][(C 2 ) 2 OPO 3 ] was recovered with 60% yield and retention of chemical structure after two consecutive dissolution cycles, which minimized the cost of developed process. The recovered PHB was used to prepare a bioplastic film, which showed good thermal and mechanical stability, as characterized by FT-IR, DSC, TGA, and DMA techniques.

Dodecylbenezenesulfonate-based anionic surface active ionic liquids (DBS-ILs) paired with onium cations, n-butyltrimethylammonium ([N1114]), 1-butyl-3-methylimidazolium ([C4mim]), and N-butylpyridinium ([C4Py]) have been synthesized. DBS-ILs were found to be highly surface active having critical micelle concentration (CMC) lower than that of their conventional analogue sodium dodecylbenezenesulfonate ([Na][DBS]). The CMC values of DBS-ILs were determined from surface tension (ST) and isothermal titration calorimetry (ITC). DBS-ILs formed micelles predominantly in the aqueous medium, and unlike [Na]DBS, the micelles of DBS-ILs could be transformed into vesicles with the addition of sodium bromide (NaBr). Micelle to vesicle transitions (MVTs) were evidenced from dynamic light scattering (DLS), turbidity, proton nuclear magnetic resonance ((1)H NMR), and cryo-TEM techniques. Thermodynamics of aggregation was investigated from ITC which indicated that the aggregation process is primarily driven by the entropy factor. The formation of a vesicle upon addition of NaBr has been accounted to the increased electrostatic interactions between the less hydrated sulfonate headgroup and the more populated bigger sized counterions along with the favored cation-π or π-π interactions between them as evidenced from 2D-NOESY NMR experiments. The stimuli-responsive morphological transitions in the self-assembly of the reported anionic surface active ionic liquids (SAILs) will be useful for encapsulation and delivery of active (bio)molecules in the targeted biomedical applications.