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Efficient drug delivery vehicles, hydroxyapatite modified by carboxylic acids, were prepared by an in situ co-precipitation method. The presence of functional groups and subsequent surface properties of modified HA improved ibuprofen loading and release efficiency.

Degradable implant membranes designed to separate hard and soft tissues and to trigger the growth of underlying bone and with antimicrobial properties are needed for the management of bone defects, ridge augmentation and to facilitate dental implants. In this study, the composite scaffolds of poly(lactic acid) (PLA), poly(caprolactone) (PCL) blended with nano hydroxyapatite and cefixime‐β cyclodextrin (Cfx‐βCD) inclusion complexes were synthesized by electrospinning. The prepared electrospun fibrous membranes were characterized by scanning electron microscopy and Fourier transform infrared (FTIR) spectroscopy. Membranes were microporous with random fibers in the range of 0.2–0.37 µm. The data from FTIR spectral analysis helped to characterize the presence of PCL, PLA, Cfx, and βCD in the electrospun membranes. In addition, the mechanical properties (i.e., elastic modulus and tensile strength) of the scaffolds were investigated. The mechanical strength and suture retention ability of the membranes was comparable to that of skin grafts. Drug release assays confirmed the slow release of Cfx from the membranes in the presence of βCD and antimicrobial studies showed that the membranes possessed antibacterial properties. The interaction of cells with membranes was evaluated by culturing them with the mouse pre‐osteoblast cell line MC3T3 and assessment of bone formation was done using Alizarin Red Assay. Culturing MC3T3 cells on the scaffolds showed that cells attached and entered the membranes and increased in number over time. In summary, these membranes are flexible, strong, bactericidal and osteogenic, which are the ideal implant properties for dental and maxillofacial surgery. POLYM. COMPOS., 40:1564–1575, 2019. © 2018 Society of Plastics Engineers

Ionic liquid coated nanoparticles (IL-NPs) consisting of zero-valent iron are shown to display intrinsic peroxidase-like activity with enhanced potential to catalyze the oxidation of the chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide. This results in the formation of a blue green colored product that can be detected with bare eyes and quantified by photometry at 652 nm. The IL-NPs were further doped with bismuth to enhance its catalytic properties. The Bi-doped IL-NPs were characterized by FTIR, X-ray diffraction and scanning electron microscopy. A colorimetric assay was worked out for hydrogen peroxide that is simple, sensitive and selective. Response is linear in the 30-300 μM HO concentration range, and the detection limit is 0.15 μM. Graphical abstract Schematic of ionic liquid coated iron nanoparticles that display intrinsic peroxidase-like activity. They are capable of oxidizing the chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide. This catalytic oxidation generated blue-green color can be measured by colorimetry. Response is linear in the range of 30-300 μM HO concentration, and the detection limit is 0.15 μM.

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In this study, a stable ionic liquid (IL) mediated zero-valent copper nanoparticle (nZVCu), namely IL-nZVCu, has been evaluated for catalytic properties towards H 2 O 2 -mediated TMB (3, 3',5,5'-tetramethylbenzidine) reaction under normal conditions of temperature and pH. The various analytical techniques like Fourier Transform Infrared Spectroscopy (FT-IR), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), X-ray powder diffraction (XRD), scanning electron microscope (SEM), Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) were used to confirm the structure and nano size of nZVCu. The simple protic IL 1-hydrogen-3-methylimidazolium acetate (HmimOAc) with its cation 1-methylimidazole and anion acetate was synthesized, characterized, and coated on nZVCu to prepared IL-nZVCu. As a novel mimic peroxidase, IL-nZVCu could quickly catalyze the oxidation reaction of specific chromogenic substrate TMB, when H 2 O 2 acts as an oxidant, followed by a remarkable color change in the solution measured by UV/Vis Spectrophotometry. The enhanced catalytic activity and significant color change were greatly dependent on the catalyst dosage, the volume of IL taken, incubation time, H 2 O 2 concentration, and TMB concentration. Also, IL-nZVCu showed no response toward ascorbic acid, cholesterol, dopamine, urea and uric acid. Based on these findings, IL-nZVCu could be effectively used for visual colorimetric sensing of H 2 O 2 with a limit of detection (LOD) of 44 μM over the dynamic linear range from 40 μM to 1000 μM concentration.

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