Experimental and theoretical spectroscopic analysis, hydrogen bonding, reduced density gradient and antibacterial activity study on 2-Phenyl quinoline alkaloid

Designing Thieno[3,4-c]pyrrole-4,6-dione Core-Based, A2-D-A1-D-A2-Type Acceptor Molecules for Promising Photovoltaic Parameters in Organic Photovoltaic Cells

Nonfullerene-based organic solar cells can be utilized as favorable photovoltaic and optoelectronic devices due to their enhanced life span and efficiency. In this research, seven new molecules were designed to improve the working efficiency of organic solar cells by utilizing a terminal acceptor modification approach. The perceived A2-D-A1-D-A2 configuration-based molecules possess a lower band gap ranging from 1.95 to 2.21 eV compared to the pre-existing reference molecule (RW), which has a band gap of 2.23 eV. The modified molecules also exhibit higher λmax values ranging from 672 to 768 nm in the gaseous and 715-839 nm in solvent phases, respectively, as compared to the (RW) molecule, which has λmax values at 673 and 719 nm in gas and chloroform medium, respectively. The ground state geometries, molecular planarity parameter, and span of deviation from the plane were analyzed to study the planarity of all of the molecules. The natural transition orbitals, the density of state, molecular electrostatic potential, noncovalent interactions, frontier molecular orbitals, and transition density matrix analysis of all studied molecules were executed to validate the optoelectronic properties of these molecules. Improved charge mobilities and dipole moments were observed, as newly designed molecules possessed lower internal reorganization energies. The open circuit voltage (Voc) of W4, W5, W6, and W7 among newly designed molecules was improved as compared to the reference molecule. These results elaborate on the superiority of these novel-designed molecules over the pre-existing (RW) molecule as potential blocks for better organic solar cell applications.

Recent Advances in PLA-Based Antibacterial Food Packaging and Its Applications

In order to reduce environmental pollution and resource waste, food packaging materials should not only have good biodegradable ability but also effective antibacterial properties. Poly(lactic acid) (PLA) is the most commonly used biopolymer for food packaging applications. PLA has good physical properties, mechanical properties, biodegradability, and cell compatibility but does not have inherent antibacterial properties. Therefore, antibacterial packaging materials based on PLA need to add antibacterial agents to the polymer matrix. Natural antibacterial agents are widely used in food packaging materials due to their low toxicity. The high volatility of natural antibacterial agents restricts their application in food packaging materials. Therefore, appropriate processing methods are particularly important. This review introduces PLA-based natural antibacterial food packaging, and the composition and application of natural antibacterial agents are discussed. The properties of natural antibacterial agents, the technology of binding with the matrix, and the effect of inhibiting various bacteria are summarized.

New benzyltriethylammonium/urea deep eutectic solvent: Quantum calculation and application to hyrdoxylethylcellulose modification

In this paper, a new deep eutectic solvent (DES) has been successfully synthesized that is based on benzyltriethylammonium bromide as a hydrogen bond acceptor (HBA) and urea as a hydrogen bond donor (HBD). However, its usability in modifying cellulose derivatives, especially acylating hydroxyethylcellulose (HEC) was investigated. The chemical modification (acetylation) of HEC was carried out in BTEAB/urea DES system without any additional conventional solvent or catalyst. However, the proposed structure of acetylated HEC (HECA) was confirmed according to the structural spectra analyses FTIR-ATR, ¹H, ¹³C, and APT-NMR. The crystalline behavior of acetylated and unmodified HEC in the DES system has been evaluated using XRD patterns, where the thermal stability was evaluated basing on the TD-TGA thermograms. Hence, SEM images and EDX spectra were recorded to prove the changes that are expected at the morphological level and elemental profile. Yet, the nanometric sheets aspect was observed. The Functional Density Theory (DFT) was investigated as a useful computational tool to understand mechanism and donor-acceptor interactions. The topological parameters (electron density Laplacian, kinetic energy density, potential energy density, and energy density) at the bond critical points (BCP), between TBEAB and urea, are deducted according to Quantum Bader's theory, and Atoms-in-molecules (AIM). The non-covalent interactions and steric effect in the DES system were studied using the reduced density gradient isosurface (RDG). Theoretical and computational calculations revealed that the H-bonds and the electrostatic coexist, as predominant interactions in the BTEAB-based DES resulting chemical structure, and mechanism formation. The physical interactions between the component entities of DES lead to a new equilibrium that is more stable than that of HBA and HBD in their separate states.

Pyrolysis of penicillin fermentation residue and sludge to produce biochar: Antibiotic resistance genes destruction and biochar application in the adsorption of penicillin in water

A process of antibiotic fermentation residue and sludge pyrolysis to produce biochar was proposed, with antibiotic resistance genes destruction and biochar application in the adsorption of penicillin in water. The results showed that the β-lactam resistance genes were completely destroyed during pyrolysis. The prepared biochar from antibiotic fermentation residues (AFRB) and sludge (AFSB) at 800 °C and 600 °C had a good adsorption effect on the low concentration penicillin in water, with removal efficiencies of 93.32% and 98.50% for penicillin in aqueous solution and maximum adsorption capacities of 44.05 mg/g and 23.26 mg/g, respectively. Characterization of AFRB revealed that its surface was predominantly aromatic carbon, AFSB contained significant amounts of Fe₃O₄. Weak interactions (H‧‧‧π, H‧‧‧O˭C, π-π interactions) and active sites (aromatic ring, H and -C˭O groups) of penicillin with aromatic structures on AFRB and the chemisorption (-C˭O-Fe-, -C˭OO-Fe-), and active sites (-C˭O, -COO- groups) of penicillin on the (110) surface of Fe₃O₄ on AFSB were revealed by quantum chemical methods. This work provides a novel pathway for the risk reduction of antibiotic production residue and sludge associated with the generation of biochar for antibiotic removal from the environment.

Swing Arm Location-Controllable DNA Walker for Electrochemiluminescence Biosensing

Here, we described a novel swing arm location-controllable DNA walker based on the DNA tetrahedral nanostructures (DTNs) for nucleic acid detection using the polycyclic aromatic hydrocarbon (PAH) microcrystals (TAPE-Pe MCs) consisting of the nonplanar molecular tetrakis(4-aminophenyl)ethene (TAPE) and planar molecular perylene (Pe) as electrochemiluminescence (ECL) luminophores. Specifically, the swing arm strands and track strands were fixed simultaneously on the DTNs to obtain the location-controllable DNA walker, which possessed an improved reaction efficiency compared to that of a fixed swing arm-based DNA walker due to the quantitative and orderly swing arm on the DTNs. On the other hand, the Pe microcrystals doped by TAPE molecules could decrease the π-π stacking of Pe molecules for the ECL efficiency enhancement, achieving a blue-shifted and intense ECL emission. Therefore, we defined this enhanced and blue-shifted ECL phenomenon as "inhibition of conjugation-driven ECL (IC-ECL)". To prove these principles, a location-controllable DNA walker-based ECL biosensor was developed with microRNA let-7a as target molecules. The ECL biosensor achieved a low detection limit of 4.92 fM within a wide linear range from 10 fM to 100 nM. This approach offers a new insight for ECL efficiency increase and location-controllable strategies with improved reaction efficiency, demonstrating potential in diagnostic analysis.

Chitosan nanoparticles based on their derivatives as antioxidant and antibacterial additives for active bioplastic packaging

Chitosan nanoparticles (CSNPs) based on their different derivatives were proposed as antioxidant and antimicrobial additives for active bioplastic packaging. Chitosan was modified with polyethylene glycol methyl ether methacrylate (PEGMA), stearyl methacrylate (SMA) and deoxycholic acid (DC) using radiation-induced graft polymerization and chemical conjugation. The modified CSNPs-g-pPEGMA, CSNPs-g-pSMA and CSNPs-DC self-assembled into nanoparticles with the size in the range of 25-60 nm. The CSNPs-DC derivative has superior antioxidant activity and the CSNPs-g-pSMA derivative exhibited outstanding antibacterial activity against growth of E.coli (95.33 %). All modified CSNPs showed their capacities to inhibit S.aureus bacterial growth (>98 %). PLA packaging films containing CSNPs-g-pSMA inhibited the growth of natural microorganism on bread slices. Different chemical functions of the CSNPs derivatives provided different gas permeability and mechanical properties of the PLA films. The CSNPs derivatives would be promising antioxidant and antimicrobial additives for bioplastics to be further used as bio-based active food packaging.