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In this study, dihydroartemisinin (DAR), an anticancer agent with low toxicity, was loaded into poly-lactic-co-glycolic acid (PLGA) nanoparticles. The obtained PLGA cores were then coated with chitosan (CS) and/or folic acid (FA) by electrostatic interactions to enhance their anticancer and cellular uptake properties. DAR-loaded PLGA nanoparticles were prepared by the solvent evaporation method. CS and FA solutions at different ratios were dispersed concurrently into the PLGA suspension to facilitate electrostatic interactions and form nanosuspensions. The physiochemical properties of nanoparticles such as average particle size (Z), polydispersity index (PDI), zeta potential (ZP), TEM image, X-ray diffraction, and encapsulation efficiency were determined. We then determined the role of FA and CS coating on the nanoparticle surface in cytotoxicity, cellular uptake, and apoptosis. We show that the resultant nanoparticles were spherical and uniform, with a coating layer containing FA and CS covering PLGA cores with a Z of 223.5±4.28 nm, PDI of 0.209±0.03, and ZP of 15.75±1.3 mV. Both FA and CS improved the cytotoxicity of nanoparticles compared to free DAR and PLGA nanoparticles in HL-60 and KB cancer cell lines. Further, FA enhanced the cellular uptake of nanoparticles to a greater extent than CS. However, CS contributed more to apoptosis induction than FA.

Cotton fabric treated by Pyrovatex CP New (PCN) and Knittex FFRC (K-FFRC) using the Pad-dry-cure method showed an excellent fire-retardant effect. However, it needed to be cured at high temperatures for a long time leading to a high loss of mechanical strength. In this study, atmospheric-pressure dielectric barrier discharge (APDBD) plasma was applied to the cotton fabric, which then was treated by flame retardants (FRs) using the pad–dry-cure method. The purpose was to have a flame-retardant cotton fabric (limiting oxygen index (LOI) ≥ 25) and a mechanical loss of the treated fabric due to the curing step as low as possible. To achieve this goal, 10 experiments were performed. The vertical flammability characteristics, LOI value and tensile strength of the treated fabrics were measured. A response model between the LOI values of the treated fabric and two studied variables (temperature and time of the curing step) was found. It was predicted that the optimal temperature and time-to-cure to achieve LOI of 25 was at 160 °C for 90 s, while the flame-retardant treatment process without plasma pretreatment, was at 180 °C and 114 s. Although the curing temperature and the time have decreased significantly, the loss of mechanical strength of the treated fabric is still high. The tensile strength and scanning electron microscopy (SEM) images of the fabric after plasma activation show that the plasma treatment itself also damages the mechanical strength of the fabric. X-ray photoelectron spectroscopy (XPS) spectra of the fabric after plasma activation and energy-dispersive spectroscopy (EDS) analysis of the flame retardant-treated (FRT) fabric clarified the role of plasma activation in this study.

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In this work, AgNPs/PVA/Cellulose was used as a substrate material for surface Raman scattering enhancement. Silver nanoparticles (AgNPs) was synthesized by Lee and Meisel's method with the average particles size of 15.4 nm. Then, this silver colloid was made a homogenous coating on polyvinyl alcohol and cellulose film and structural characteristics of this material were determined using Scanning Electron Microscopy (SEM). The findings demonstrated that the Raman shifts of the pesticide will be identified by the SERS method at 1660 cm −1 , 2234 cm −1 (strong intensity), and at 3077 cm −1 , 1033 cm −1 , 1457 cm −1 (medium intensity) when using the excited laser with wavelength of 532 nm. Under excited laser, the limit of chlorfenapyr detection is 1 ppm (mg l −1 ), allowing determination of chlorfenapyr residue in food. Potential applications identified food samples containing chlorfenapyr residue for rapid detection, low cost, non-destructive nature and minimal sample preparation.