Green Approach For Preparation Research Articles

Green grape marc biosorbents preparation for mercury removal in aqueous media

In this study, grape marc waste from Negroamaro (a South of Italy vine variety) winery production was used to prepare biosorbents for Hg(II) removal in aqueous media. A green approach was used to develop a proper biosorbent through two different grape marc washing procedures. In particular, the common chloridric acid and the greener citric acid were evaluated. The biosorbent prepared using citric acid as a washing agent (GM-CA) gave similar results to the biosorbent washed with HCl (GM-HCl) with a maximum adsorption capacity of 36.39 mg g-1. Isothermal studies revealed heterogeneous physical adsorption of Hg(II) on the biosorbents. Moreover, FTIR analysis of the grape marc-based biosorbent without and with Hg(II) confirmed ionic interactions in the biosorbent that fit with a pseudo-second-order kinetic model. Furthermore, no significant adsorption on the biosorbent was observed when two other heavy metals, copper(II) and nickel(II), previously studied for similar sorbents, were considered. Finally, the reusability of GM-CA biosorbent was also demonstrated over three cycles. Thus, the green preparation approach used in this work can be considered suitable for developing grape marc-based biosorbents.

One-step preparation and application of mussel-inspired poly(norepinephrine)-coated polydimethylsiloxane microchip for separation of chiral compounds.

In this paper, using the self-polymerization of norepinephrine (NE) and its favorable film-forming property, a simple and green preparation approach was developed to modify a PDMS channel for enantioseparation of chiral compounds. After the PDMS microchip was filled with NE solution, poly(norepinephrine) (PNE) film was gradually formed and deposited on the inner wall of microchannel as permanent coating via the oxidation of NE by the oxygen dissolved in the solution. Due to possessing plentiful catechol and amine functional groups, the PNE-coated PDMS microchip exhibited much better wettability, more stable and suppressed EOF, and less nonspecific adsorption. The water contact angle and EOF of PNE-coated PDMS substrate were measured to be 13° and 1.68 × 10(-4) cm(2) V(-1) s(-1) , compared to those of 108° and 2.24 × 10(-4) cm(2) V(-1) s(-1) from the untreated one, respectively. Different kinds of chiral compounds, such as amino acid enantiomer, drug enantiomer, and peptide enantiomer were efficiently separated utilizing a separation length of 37 mm coupled with in-column amperometric detection on the PNE-coated PDMS microchips. This facile mussel-inspired PNE-based microchip system exhibited strong recognition ability, high-performance, admirable reproducibility, and stability, which may have potential use in the complex biological analysis.

Seed-free synthesis of 1D silver nanowires ink using clove oil (Syzygium Aromaticum) at room temperature

HypothesisSilver nanowires (AgNWs) have been demonstrated to be a promising next generation conducting material and an alternative to the traditional electrode (ITO) because of its high conductivity, transparency and stability. Generally, AgNWs are synthesized by chemical method (mainly polyol reduction method) at high temperature in the presence of exotic seeds. The present work aims at the green approach for preparation and characterization of 1D AgNWs ink using clove oil (Syzygium Aromaticum) at room temperature. ExperimentsAgNWs was prepared by green synthesis using clove oil as reducing as well as capping agent at room temperature. The obtained ink was purified, filtered and redissolved in methanol. FindingsThe prepared AgNWs showed an absorption peaks at 350 and 387nm in the UV–vis spectrum due to transverse SPR mode of silver. From the HR-TEM analysis, it was observed that the AgNWs possess an average diameter and length of ∼39±0.01nm and ∼3μm, respectively. The obtained AgNWs are crystalline in nature and are arranged in a perfect crystal lattice orientation, which was confirmed from the selected area electron diffraction studies. Moreover, the X-ray diffraction analysis confirms the face centered cubic structure. The AgNWs coated glass substrate shows an electrical conductivity of ∼0.48×106S/m.