Ultrasound assisted dispersive solid phase microextraction using polystyrene-polyoleic acid graft copolymer for determination of Sb(III) in various bottled beverages by HGAAS

Thermoplastic Polyurethane-Oleic Acid (TPU-OLE) Membranes for Guided Bone Regeneration

Guided bone regeneration (GBR) is a regenerative surgical procedure in dentistry and orthopedics. The aim of this study is to fabricate a novel nano-textured, hydrophilic thermoplastic polyurethane (TPU)-based barrier membrane containing unsaturated fatty acid, oleic acid (OLE) to assist GBR. First, TPU copolymer containing OLE in different ratios was synthesized, and GBR membranes were fabricated by the solvent casting method, and then, the surface properties were improved by alkali treatment. Thus, a TPU-OLE structure was obtained with improved surface wettability, the ability to prevent bacterial adhesion, and the capability to promote cell adhesion. The contact angle reduced from 73.3° ± 1° to 30.7° ± 0.3° at TPU-OLE3, while at TPU it decreased from 121.2° ± 2.5° to 63.6° ± 0.8° after treatment with 3 M sodium hydroxide (NaOH) solution. Furthermore, plate counting assays showed that TPU-OLE membranes displayed excellent bacterial inhibition (against Escherichia coli and Staphylococcus aureus); the control group showed 6 × 107 CFU/mL of E. coli bacterial colonies, while on the plates interacting with TPU-OLE1, TPU-OLE2, and TPU-OLE3 membranes, colonies of 12 × 105, 12 × 105, and 24 × 105 CFU/mL were observed, respectively. The bacterial count on TPU-OLE1, TPU-OLE2, and TPU-OLE3 membranes decreased by 109, 164, and 12 × 105 CFU/mL at 24 h, while the control group and TPU membranes showed 1300 × 105 and 600 × 105 CFU/mL, respectively. The obtained results indicated that either alkali treatment or OLE-modified TPU produced a more hydrophilic and promotive surface for cell attachment. Therefore, we anticipate that alkali-treated TPU-OLE membranes have a great potential in GBR in future applications.

A novel block copolymer containing gadolinium oxide nanoparticles in ultrasound assisted-dispersive solid phase microextraction of total arsenic in human foodstuffs: A multivariate optimization methodology

A new poly(3-hydroxy butyrate)-b-poly(dimethyl amino ethyl methacrylate) amphiphilic block copolymer containing gadolinium oxide nanoparticles (PHB-PDMAEMA-Gd2O3-NPs) were synthesized and used as composite adsorbent for extraction of total arsenic. Characterization of the composite adsorbent material PHB-PDMAEMA-Gd2O3-NP was studied using spectroscopic techniques. Plackett-Burman design and central composite design were employed to screening and optimization of the experimental parameters. This composite adsorbent was utilized in ultrasound assisted-dispersive solid phase microextraction (UA-dSPµE) for the determination of total inorganic arsenic in foodstuffs through hydride generation atomic absorption spectrometry (HG-AAS). It demonstrates a linear relationship across arsenic concentration range of 0.07-1.12 µg/L with a correlation coefficient (0.996). It's showed an enrichment factor of 128 and a limit of detection 0.02 µg/L for total inorganic arsenic determination. Accuracy of the developed method was confirmed through the analysis of certified reference materials with 96.0-98.5% recovery. It proved to be significantly useful UA-dSPµE method for determining total inorganic arsenic in different foodstuffs.

Tumour-specific hybrid nanoparticles in therapy of breast cancer

In this study, salicylic acid (SA) dopped into poly(3-hydroxybutyrate) (PHB) and prepared nanoparticles (NPs) to increase encapsulation efficiency, anti-cancer activity of caffeic acid (Caff), and folic acid (FA) for breast cancer treatment. NPs were prepared by solvent evaporation method and characterised by FTIR, DSC, SEM, and entrapment-loading efficiencies. The mean diameter, polydispersity index (PDI), and zeta potential (ZP) were evaluated by dynamic light scattering (DLS). In vitro release and stability studies were done via eppendorf method. The cytotoxicity, cell dead and internalisation of NPs were shown by MTT, fluorescein and confocal microscopy. The diameter and ZP of NPs were 172 ± 7 nm and -29 ± 0.38 mV. The entrapment efficiencies of 5 and 10 Caff NPs were 79 ± 0.23% and 70 ± 0.42%. NPs showed good stability within 30 d and sustained release over 25 d. FA-5Caff NPs showed 37 ± 0.3% viability on MCF-7. FA-Caff NPs were identified as promising carrier system for breast cancer therapy.

Design of experiment-oriented development of solvent-free mixed micellar chromatographic method for concomitant determination of metronidazole and ciprofloxacin hydrochloride

A green, fast and robust solvent-free chromatographic method has been developed for concomitant analysis of ciprofloxacin HCl and metronidazole in bulk powder as well as in dosage form using levofloxacin as internal standard (I.S.). Two different designs including fractional factorial (FFD) and Box-Behnken (BBD) designs were implemented for screening and optimization steps, respectively. The optimum chromatographic separation was accomplished using mobile phase composed of 0.13 M sodium dodecyl sulfate and 0.02 M Birij-35 solution adjusted to pH 2.5 using phosphoric acid at a flow rate of 1.3 mL/min and column oven temperature of 40 °C. Chromatographic analysis was performed on X-Bridge (150 mm × 4.6 mm, 5 μm) column with UV detection at 280 nm. A linear response was acquired over the range of 0.4-50 μg/mL for both drugs. The developed method was applied for quantitation of cited drugs in commercially available tablet with mean percent recovery ± SD of 99.45 ± 0.72 and 100.13 ± 0.81 for metronidazole and ciprofloxacin respectively. The method was proven to be green as evaluated by three greenness assessment tools. The run time was 8 min, thus saving time and reagent.