Release Of Benzoic Acid Research Articles

Biochar Reduces Generation and Release of Benzoic Acid from Soybean Root

Biochar Reduces Generation and Release of Benzoic Acid from Soybean Root

Effectiveness of Mesoporous Silica Nanoparticles Functionalized with Benzoyl Chloride in pH-Responsive Anticorrosion Polymer Coatings.

Smart polymer coatings embedding stimuli-responsive corrosion inhibitor nanocarriers are commonly exploited, in the literature, for the development of high-performance active coatings. In this work, high-surface-area amino-functionalized mesoporous silica nanoparticles (MSN-NH2) were developed with a one-step synthesis process and then functionalized with benzoyl chloride (MSN-BC) through a reaction with amino groups. MSN-BC are able to release benzoic acid (BA) in acid and alkaline conditions as a result of the hydrolysis of the pH-sensitive amide bond. MSN-BC were embedded in polymer coatings to exploit the pH-dependent release of corrosion-inhibiting BA. After an in-depth characterization of the developed functional nanoparticles and of their pH-dependent release kinetics of BA, MSN-BC were embedded in an acrylic matrix, realizing coatings for the corrosion protection of aluminum AA2024 alloys. Results demonstrate the effectiveness of the nanoparticles' porous structure for a high loading of the anticorrosive active agent BA and the long-lasting efficiency of the coating for the corrosion protection of aluminum alloys, as validated by morphological and electrochemical impedance spectroscopy (EIS) measurements. EIS experiments were carried out with up to 21 days of exposure to a corrosive environment, revealing the potentialities of the acrylic coatings embedding MSN-BC for the protection of aluminum alloys.

Rapid Aqueous Photouncaging by Red Light.

This work describes three new red-photocleavable dyes. The best-performing dye exhibits a quantum yield of 5.7% in 30:70 v/v water/acetonitrile and approximately 80% release of benzoic acid using a 626 nm LED. Photo-orthogonality between this dye and a UV-activated photouncaging group was demonstrated. Additionally, a qualitative comparison between the same pair of dyes in a gel was performed, highlighting the superior penetration depth that can be achieved using the newly reported dye.

Mechanisms of biodegradation of dibenzoate plasticizers

Biodegradation mechanisms were elucidated for three dibenzoate plasticizers: diethylene glycol dibenzoate (D(EG)DB), dipropylene glycol dibenzoate (D(PG)DB), both of which are commercially available, and 1,6-hexanediol dibenzoate, a potential green plasticizer. Degradation studies were done using Rhodococcus rhodochrous in the presence of pure alkanes as a co-substrate. As expected, the first degradation step for all of these systems was the hydrolysis of one ester bond with the release of benzoic acid and a monoester. Subsequent biodegradation of the monobenzoates of diethylene glycol (D(EG)MB) and dipropylene glycol (D(PG)MB) was very slow, leading to significant accumulation of these monoesters. In contrast, 1,6-hexanediol monobenzoate was quickly degraded and characterization of the metabolites indicated that the biodegradation proceeded by way of the oxidation of the alcohol group to generate 6-(benzoyloxy) hexanoic acid followed by β-oxidation steps. This pathway was blocked for D(EG)MB and D(PG)MB by the presence of an ether function. The use of a pure hydrocarbon as a co-substrate resulted in the formation of another class of metabolites; namely the esters of the alcohols formed by the oxidation of the alkanes and the benzoic acid released by hydrolysis of the original diesters. These metabolites were biodegraded without the accumulation of any intermediates.

Thermosensitivity of N-isopropylacrylamide hydrogels cross-linked with degradable cross-linker

Thermosensitive N-isopropylacrylamide (NIPA)-based hydrogels have been prepared using a biodegradable pseudo-peptide (DMTLT, a tri-molecular adduct of tyrosine, lysine, tyrosine) as cross-linker. This new cross-linker provides a similar cross-linking efficiency as N,N′ methylenbisacrylamide (BIS) (a standard biostable cross-linker) used as reference. The amount of DMTLT has shown to modulate, in addition to the cross-linking density, the transition temperature (the higher the amount of DMTLT, the lower the transition temperature), as well as the morphology and the whole aqueous behaviour. The incorporation of hydrophilic N,N′-dimethylacrylamide (DMA) increases the transition temperature, as expected. Finally, the matrices have exhibited in aqueous media a well-defined pulsatile behaviour in swelling and release of benzoic acid and dextran as models of ionisable molecules and non-ionisable macromolecules.

Kinetics of a drug release from a delayed release device

Reaction of sodium salt of benzoic acid with methacryloyl chloride provides an anhydride which is polymerized by the radical method or copolymerized with various percentages of ethylene glycol dimethacrylate to obtain crosslinked products. Hydrolysis reactions of the resulting polymers were carried out in various aqueous solutions and the rate of release of benzoic acid (simulator of drug) seems to depend both on the percentages of crosslinking comonomer and on the pH of the solution. A model of this delayed release of benzoic acid is also proposed.

Benzoyl chloride modified ionomer films as antimicrobial food packaging materials

Modified ionomer films were prepared and their antimicrobial abilities were investigated. The anhydride linkage of the modified films was manufactured via the reaction of acid/base‐treated films with benzoyl chloride as evidenced by the specific anhydride absorption (–CO–O–CO–, 1807 cm−1 and 1741 cm−1; –C–O–C–, 1009 cm−1) in Fourier‐transform infrared (FT‐IR) spectra. Release of benzoic acid from the modified ionomer films either immersed in buffer solutions or buried between two layers of potato dextrose agar (PDA) media was detected by high performance liquid chromatography (HPLC) that implied the feasibility of the modified ionomer films as an antimicrobial food packaging material. It showed that the base‐treated modified films expressed better choice as an antimicrobial food packaging materials than the acid‐treated ones because of the higher amount of benzoic acid released from the former than from the later. The antimicrobial ability of modified ionomer films was further demonstrated by its inhibition against the growth of Penicillium sp. and Aspergillusniger. The modified ionomer films successfully exhibited high efficiency in the inhibition of microbial growth.

Zero order release from glassy hydrogels. II. Matrix effects

A series of copolymers of 2 -hydroxyethyl methacrylate (HEMA) with a hydrophobic monomer, methoxyethyl methacrylate (MEMA), and a hydrophilic monomer, methoxyethoxyethyl methacrylate (MEEMA), was evaluated as matrices for the release of benzoic acid and theophylline. The results are discussed in the context of the criteria developed in the literature for zero order release from glassy hydrogels. Release of theophylline from a p (HEMA-MEMA) matrix containing 22% MEMA followed zero order kinetics. Benzoic acid was released at constant rate from all the matrices.

Diffusion in porous materials above the percolation threshold.

The diffusion of water-soluble solutes in water-soaked porous media was studied by following the release of benzoic acid from poly(vinyl stearate) matrices. The results were analyzed using a pseudo-steady-state diffusion model coupled with the fundamental concepts of percolation theory. The results of the study indicated that the relationship between the bulk diffusion coefficient of benzoic acid in the polymer matrix and the porosity was well described by percolation scaling laws. A very low percolation threshold (0.07) was experimentally observed for this system.

Drug release from Pluronic F-127 gels

Low toxicity, reverse thermal gelation and high drug loading capabilities, suggest that PF-127 gels have great potential as a drug delivery system. The release of benzoic acid and related compounds from Pluronic F-127 (PF-127) gels has been studied in an in vitro release model. Release of the model drugs has been shown to decrease with increasing poloxamer concentration which is probably due to an increase in size and number of micelles and a subsequent decrease in size and number of aqueous channels. The diffusion coefficients of benzoic acid and p-hydroxybenzoic acid have been shown to decrease in an apparent exponential manner with respect to PF-127 concentration. The influence of drug lipophilicity on drug release has been studied by use of a series of p-hydroxybenzoate esters at three different temperatures. An increase in lipophilicity causes a decrease in release rate of the esters due to a greater partitioning into the micellar region within the gel structure. The energies of activation for diffusion of the p-hydroxybenzoate esters were estimated from their temperature dependence and were shown to increase with an increase in lipophilicity.