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Carbonic anhydrase (CA) has been immobilized on surfactant-modified silylated chitosan (SMSC) for the carbonation reaction. CA immobilized on SMSC was characterized using a scanning electron microscope, energy-dispersive X-ray and X-ray diffraction spectroscopy, and Fourier transform infrared analysis. The effect of various parameters, such as pH, temperature, and storage stability, on immobilized CA was investigated using a p-nitrophenyl acetate (p-NPA) assay. The optimum pH and temperature were determined to be 7 and 35 °C, respectively. Kinetic parameters of immobilized and free CA (K m and V max values) were also evaluated. For immobilized CA, the K m value was 4.547 mM and the V max value was 1.018 mmol min -1 mg -1 , whereas for the free CA, the K m value was 1.211 mM and the V max value was 1.125 mmol min -1 mg -1 . It was observed that immobilized CA had longer storage stability and retained 50% of its initial activity up to 30 days. Proof of concept has been established for the biomimetic carbonation reaction. The CO 2 sequestration capacity in terms of conversion of CO 2 to carbonate was quantified by gas chromatography (GC). It was 10.73 and 14.92 mg of CaCO 3 /mg of CA for immobilized and free CA, respectively, under a limiting concentration of CO 2 (14.5 mg of CO 2 /10 mL).

Poly lactic acid is a biodegradable, biocompatible, and non-toxic polymer, widely used in many pharmaceutical preparations such as controlled release formulations, parenteral preparations, surgical treatment applications, and tissue engineering. In this study, we prepared lipid-polymer hybrid nanoparticles for topical and site targeting delivery of Norfloxacin by emulsification solvent evaporation method (ESE). The design of experiment (DOE) was done by using software to optimize the result, and then a surface plot was generated to compare with the practical results. The surface morphology, particle size, zeta potential and composition of the lipid-polymer hybrid nanoparticles were characterized by SEM, TEM, AFM, and FTIR. The thermal behavior of the lipid-polymer hybrid nanoparticles was characterized by DSC and TGA. The prepared lipid-polymer hybrid nanoparticles of Norfloxacin exhibited an average particle size from 178.6 ± 3.7 nm to 220.8 ± 2.3 nm, and showed very narrow distribution with polydispersity index ranging from 0.206 ± 0.36 to 0.383 ± 0.66. The surface charge on the lipid-polymer hybrid nanoparticles were confirmed by zeta potential, showed the value from +23.4 ± 1.5 mV to +41.5 ± 3.4 mV. An Antimicrobial study was done against Staphylococcus aureus and Pseudomonas aeruginosa, and the lipid-polymer hybrid nanoparticles showed potential activity against these two. Lipid-polymer hybrid nanoparticles of Norfloxacin showed the %cumulative drug release of 89.72% in 24 h. A stability study of the optimized formulation showed the suitable condition for the storage of lipid-polymer hybrid nanoparticles was at 4 ± 2 °C/60 ± 5% RH. These results illustrated high potential of lipid-polymer hybrid nanoparticles Norfloxacin for usage as a topical antibiotic drug carriers.

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Topological insulators (TIs) possess exciting nonlinear optical properties due to presence of metallic surface states with the Dirac fermions and are predicted as a promising material for broadspectral phodotection ranging from UV (ultraviolet) to deep IR (infrared) or terahertz range. The recent experimental reports demonstrating nonlinear optical properties are mostly carried out on non-flexible substrates and there is a huge demand for the fabrication of high performing flexible optoelectronic devices using new exotic materials due to their potential applications in wearable devices, communications, sensors, imaging etc. Here first time we integrate the thin films of TIs (Bi2Te3) with the flexible PET (polyethylene terephthalate) substrate and report the strong light absorption properties in these devices. Owing to small band gap material, evolving bulk and gapless surface state conduction, we observe high responsivity and detectivity at NIR (near infrared) wavelengths (39 A/W, 6.1 × 108 Jones for 1064 nm and 58 A/W, 6.1 × 108 Jones for 1550 nm). TIs based flexible devices show that photocurrent is linearly dependent on the incident laser power and applied bias voltage. Devices also show very fast response and decay times. Thus we believe that the superior optoelectronic properties reported here pave the way for making TIs based flexible optoelectronic devices.