Bis-corannulenoanthracene (C50H22, 5) was prepared by the Diels-Alder double cycloaddition of isocorannulenofuran with "bis-benzyne", followed by deoxygenation of the adducts. Despite the presence of a pentacene core, 5 is stable enough to be isolated and stored. A cycloaddition reaction of 5 with maleic anhydride produces 10 which exhibits strong affinity toward C60, as evidenced by (1)H NMR titration experiment. Synthesis of 10 demonstrates the synthetic utility of hydrocarbon 5 in the preparation of the barrelene-based molecular clips with two benzocorannulene pincers adorned with polar substituents on their tethers, which will allow for immobilization of the receptors on solid supports.

Garcinol, a well-known medicinal phytochemical, was extracted and isolated from the dried fruit rinds of Garcinia quaesita Pierre. In this study, garcinol has successfully used to reduce silver ions to silver in order to synthesize garcinol-capped silver nanoparticles (G-AgNPs). The formation and the structure of G-AgNPs were confirmed by UV-visible spectroscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. The antimicrobial activity of garcinol and G-AgNPs were investigated by well diffusion assays, broth micro-dilution assays and time-kill kinetics studies against five microbial species, including Staphylococcus aureus (ATCC 25923), Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 25922), Candida albicans (ATCC 10231) and clinically isolated methicillin-resistant Staphylococcus aureus (MRSA). The formation of G-AgNPs is a promising novel approach to enhancing the biological activeness of silver nanoparticles, and to increase the water solubility of garcinol which creates a broad range of therapeutic applications.

Nitrocellulose with silver nanoparticle (AgNP/NC) composite was prepared in situ using Ag(CH3CO2) and nitrocellulose without any reducing agent. The composite materials synthesized were spray coated onto glass substrates to obtain thin films. The AgNPs/NC composites were characterized by ultraviolet-visible, Fourier transform infrared, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The antimicrobial activity of AgNPs/NC composite was investigated by tube method and time-kill kinetic studies against three microbial species, including Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 25923), and Candida albicans (ATCC 10231). The antibiofilm activities were qualitatively determined against all three organisms. Prepared AgNPs/NC films exhibited good antimicrobial activity and significant inhibition of biofilm development against all three microbial species. The effective dispersion of AgNPs/NC in biofilm was responsible for the significant antibiofilm activity of the prepared material. The reported AgNPs/NC composite can be used as coating additive in bacteriocidal paint which can be applied onto surfaces such as in healthcare environments.

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Chitosan is a well-studied biomaterial which has been widely used for environmental applications as an efficient natural polymer for the adsorption and removal of metal ions. Owing to its unique properties, chitosan shows good metal-binding behavior toward several different metal ions such as Cu2+, Zn2+, Cd2+, Ni2+, Co2+, and Ca2+. Chemical modifications with the introduction of functional groups have been carried out extensively and thereby producing various chitosan derivatives to increase the selectivity and adsorption capacity toward metal ions. The present work focuses on two such monofunctional derivatives, namely, carboxymethyl chitosan (CMC) and ethylenediaminetetraacetic acid chitosan (EDTA-CS) which have been recognized as excellent adsorbents for metal removal. The main objective of this study was to synthesize a new bifunctional chitosan derivative, namely, ethylenediaminetetraacetic acid–carboxymethyl chitosan (EDTA-CMC) by attaching both carboxymethyl and EDTA functional groups on the polymer backbone and thereby enhancing its metal-binding properties. The bifunctional derivative synthesis was conducted by combining the procedures of synthesis of CMC and EDTA-CS. Newly synthesized EDTA-CMC derivative was characterized by Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscope analysis, and thermogravimetric analysis. Adsorption properties of EDTA-CMC were investigated with Cu2+ ions which produced an adsorption capacity of 111.90 mg g−1 for 1000.0 mg/L and 12.20 mg g−1 for 10.00 mg/L Cu2+ solutions. The preliminary results revealed that EDTA-CMC is an effective adsorbent than CMC to remove Cu2+ in aqueous samples. The effects of pH, initial concentration, and mass of the adsorbent in the adsorption process were studied. Under the optimized parameters of an adsorbent dosage of 10.00 mg and pH 5.5, a comparable maximum adsorption capacity up to 112.44 mg g−1 was achieved with a 150.00 mg/L of Cu2+ solution. Furthermore, EDTA-CMC showed good adsorption performance even after five cycles of regeneration.