In the current work, an enantioselective imprinting technique was used to develop a very selective adsorbent for the (+)-cathine ((+)-Cat) enantiomer. The phenolic sulfonamide produced from ...2,4-dihydroxybenzenesulfonic acid (HBS) and (+)-Cat ((+)-Cat-HBS) was initially synthesized by triphenylphosphene activation and subsequently involved in condensation polymerization with resorcinol in the presence of formaldehyde under acidic conditions. Alkaline sulfonamide bond-breaking was subsequently employed to separate the (+)-Cat template from the polymer, and the resulting imprinted resin ((+)-CIP) displayed high selectivity for the (+)-Cat, with a capacity of 225 ± 2 mg/g. Studies of selectivity also showed that the (+)-Cat enantiomer was preferred over its counterpart because of the development of configurationally matching receptors. In addition, the produced resin was used for the enantioresolution of (±)-Cat racemate by column method, yielding a loading supernatant solution with an enantiomeric excess of (+)-Cat 50% and a recovery eluant solution with an excess of (-)-Cat 85%.
Using microwave technique in the presence of citric acid, selenium nanoparticles (SeNPs) were fabricated. The morphological characteristics revealed that the spherical SeNPs with diameters ranging ...from 10.5 to 20 nm aggregated spherical shapes with sizes ranging from 0.67 to 0.83 mm. Moreover, the antioxidant efficacy was assessed by the DPPH radical scavenging test, which depicted that green-prepared nanoparticle at a 106.3 mg/mL dosage had the maximum scavenging capacity (301.1 ± 11.42 mg/g). Otherwise, with nanoparticle concentrations of 500 mg/ml, in vitro cell viability of SeNPs through human breast cancer MCF-7 cell lines was reduced to 61.2 ± 2.2% after 1 day of exposure. The antibacterial activity was tested against G-negative
Pseudomonas aeruginosa (P. aeruginosa) and Escherichia coli
(
E. coli
), G-positive bacteria
Bacillus subtilis (B. subtilis)
,
and Staphylococcus aureus
(
S. aureus
), which demonstrated that SeNPs had little activity against
S. aureus
. Still, it had the highest activity against
E. coli
, with a zone of inhibition (ZOI) of 25.2 ± 1.5 mm compared to 16.0 ± 0.6 mm for the standard antibiotic. Most notably, biogenic SeNPs have anticoagulant activities using activated partial thromboplastin time (aPTT) assessment. Based on previous findings, SeNPs can be used in medical aid and their cell viability, antioxidant, anticoagulant, and effects on bacteria.
S-Mandelic acid (MA) enantio-selective resinous material functionalized with –NH2 groups has been developed and effectively utilized in chiral separation of (±)-MA racemate solution. S-MA has first ...combined with the polymerizable p-aminophenol and form the corresponding amide derivative, which was then polymerized with phenol/formalin using HCl as a catalyst. The stereo-selective –NH2 functionalized binding sites were then generated within the resin upon the alkaline degradation of the amide linkages followed by acidic treatments that will expel the resin incorporated S-MA out of the polymeric material to get the S-MA imprinted polymer (S-MAPR). The synthesized S-MA chiral amide derivative along with the developed polymeric resin was investigated by various techniques including FTIR and NMR spectra that confirmed the executed chemical modifications. In addition, the morphological appearance of the obtained resins were observed using SEM images. Moreover, the S-MAPR resin was examined to optimize the enantio-selective separation conditions and the studies indicated that the adsorption reached the highest value at pH 7 and the maximum capacity was 243 ± 1 mg/g. In addition, the chiral separation of (±)-MA racemic solution was successfully executed by the S-MAPR separation column with 55% and 82% enantiomeric excess of R- and S-MA within both the initial loading and recovery eluant solutions, respectively.
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•Polymerizable S-mandelic acid-p-aminophenol amide derivative (S-MA-AP) was synthesized.•The prepared S-MA-AP was implemented in polymerization with phenol and formalin.•The S-mandelic acid enantiomer was extracted from the polymer matrix.•The selective performance of the prepared S-MAPR resin was evaluated to anticipate the optimum uptake conditions.•The polymeric resin was applied for chiral resolution of (±)-mandelic acid racemate.
The main aim of this work is the preparation of azo dye modified chitosan that was subsequently used in the ion-imprinting of Cr(III) ions to finally obtain ion-selective sorbent able to selectively ...combine with Cr(III) ions from water when coexisting with other similar metal ions. The azo dye derived from resorcinol and p-aminobenzoic acid was prepared and then linked to the chitosan amino groups by amide linkages utilizing EDC/NHS coupling agent. A polymeric complex of the azo dye chitosan derivative AZCS and Cr(III) ions was then prepared and treated with glyoxal solution, which cross-link the main chitosan chains in form of micro-spherical beads in presence of the coordinated Cr(III) ions that were later expelled out of the texture of the beads using acidified EDTA eluent solution while preserving the spatial and geometrical shape of the resulting Cr(III) ions chelating sites.
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The AcPase exhibits a specific activity of 31.32 U/mg of protein with a 728-fold purification, and the yield of the enzyme is raised to 3.15 %. The Zn2+-dependent AcPase showed a purification factor ...of 1.34 specific activity of 14 U/mg of proteins and a total recovery of 5.14. The SDS-PAGE showed a single band corresponding to a molecular weight of 18 kDa of AcPase and 29 kDa of Zn2+-dependent AcPase. The AcPase enzyme has shown a wide range of substrate specificity for p-NPP, phenyl phosphate and FMN, while in the case of ZnAcPase α and β-Naphthyl phosphate and p-NPP were proved to be superior substrates. The divalent metal ions like Mg2+, Mn2+, and Ca2+ increased the activity, while other substrates decreased the enzyme activity. The Km (0.14 mM) and Vmax (21 μmol/min/mg) values of AcPase were higher than those of Zn2+-AcPase (Km = 0.5 mM; Vmax = 9.7 μmol/min/mg). The Zn2+ ions activate the Zn2+-AcPase while Fe3+, Al3+, Pb2+, and Hg2+ showed inhibition on enzyme activity. Molybdate, vanadate and phosphate were found to be competitive inhibitors of AcPase with Ki values 316 μM, 185 μM, and 1.6 mM, while in Zn2+-AcPase tartrate and phosphate also showed competitive inhibition with Ki values 3 mM and 0.5 mM respectively.
•A novel Acid phosphatases and zinc dependent acid phosphatases were purified from chicken’s brain.•AcPase and zinc-dependent AcPase showed a single protein band on SDS-PAGE corresponding to molecular weights of about 18 kDa and 29 kDa.•The Acid phosphatase and zinc dependent AcPases were optimally active at 45 °C pH 6.0.•The Km of zinc-dependent AcPase and AcPase has been determined to be 0.5 mM and 0.14 mM, respectively. The Vmax 7 μmol/min/mg of protein and 21 μmol/min/mg of protein.
Developing a sorbent for the removal of La3+ ions from wastewater offers significant environmental and economic advantages. This study employed an ion-imprinting process to integrate La3+ ions into a ...newly developed derivative of aminoguanidine-chitosan (AGCS), synthesized via an innovative method. The process initiated with the modification of chitosan by attaching cyanoacetyl groups through amide bonds, yielding cyanoacetyl chitosan (CAC). This derivative underwent further modification with aminoguanidine to produce the chelating AGCS biopolymer. The binding of La3+ ions to AGCS occurred through imprinting and cross-linking with epichlorohydrin (ECH), followed by the extraction of La3+, resulting in the La3+ ion-imprinted sorbent (La-AGCS). Structural confirmation of these chitosan derivatives was established through elemental analysis, FTIR, and NMR. SEM analysis revealed that La-AGCS exhibited a more porous structure compared to the smoother non-imprinted polymer (NIP). La-AGCS demonstrated superior La3+ capture capability, with a maximum capacity of 286 ± 1 mg/g. The adsorption process, fitting the Langmuir and pseudo-second-order models, indicated a primary chemisorption mechanism. Moreover, La-AGCS displayed excellent selectivity for La3+, exhibiting selectivity coefficients ranging from 4 to 13 against other metals. This study underscores a strategic approach in designing advanced materials tailored for La3+ removal, capitalizing on specific chelator properties and ion-imprinting technology.
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Polyvinyl alcohol (PVA) cinnamate ester derivative (PVCN) was prepared by partial esterification of PVA using cinnamoyl chloride with various extents and then was examined using different ...instrumental and spectral techniques that confirm the chemical structure of the photo-active product. The obtained PVCN derivatives were casted in membranes that were able to cross-link when exposed to a strong UV light via 2π + 2π cycloaddition reaction, which was traced by UV–vis light spectra. The textures of the obtained membranes were then observed by SEM after freeze-drying to evaluate the effect of esterification degree on the cross-linking density. The PVCN membranes were also utilized as carrier support to immobilize the lactase enzyme by entrapment method and the immobilized lactase kept around 76% of its activity and presented remarkable thermal stability and resistance toward the environmental pH disturbances compared to the soluble lactase. Moreover, the kinetic parameters obtained from the kinetic experiments demonstrated an observed decrease in the vmax values from 40.35 to 27.62 U mg−1along with an increase in the Km values from 0.203 to 0.432 mM upon the lactase entrapment, which implies a depressed affinity between the lactase and its substrate. However, after 8 reuse cycles, the entrapped lactase still maintained around 85% of its activity revealing promising economic feasibility of the utilized entrapment technique.
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•Polyvinyl alcohol was functionalized with the photo-active cinnamoyl ester moieties.•The chemical structure of the photo-responsive derivative was investigated.•The PVA-cinnamic ester derivative was cross-linked upon UV irradiation.•The obtained photo-responsive polymer was employed in entrapment of lactase enzyme.•The activity of the immobilized and free enzymes was studied under different conditions.
In the last decade, high-performance liquid chromatography/tandem mass spectrometry (LC/MS/MS) combined with electrospray ionization (ESI) has been widely used for determining low concentrations of ...steroids, and derivatization has often been employed to enhance detection. In the present study, endogenous steroids were extracted using a Strata-XL polymeric reverse phase cartridge. The isolated steroids were reacted with 2-hydrazino-1-methylpyridine (HMP) at 50 °C for 30 min. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used in a positive mode with multiple reaction monitoring (MRM) for the quantification of testosterone (T) and its precursor, dehydroepiandrosterone (DHEA), in saliva samples collected from twenty young Saudi professional soccer players. The analytes were separated on an ACE Ultracore 2.5 Superphenylhexyl column (150 × 3.0 mm id). The extraction recovery during the pre-treatment was >89% and gave <±20% for inter- and intra-assay precision and accuracy. The limits of quantification (LOQ) were found to be 20 pg/mL for (T and DHEA) and 50 pg/mL for Epitestosterone (EPI). The results showed no significant variation in the concentration of T between pre and post training, whereas DHEA was significantly increased after short-term exercise. These results could indicate that there is no correlation between T and its precursor DHEA level following short term physical activity. EPI concentrations could not be detected with a LOQ of 50 pg/mL in the saliva samples.
Mosquitoes serve as reservoirs for viruses and other microorganisms, posing a significant health‐related issue for both humans as well as livestock. Control of these deadly disease‐producing mosquito ...vectors is of paramount importance. The chemical analysis of Parmotrema reticulatum was examined by GC–MS. Further, lichen‐mediated AgNPs were confirmed through UV–vis spectrophotometry, FTIR, TEM‐EDX, and XRD. After 24 h post‐treatment, the lichen‐synthesized AgNPs showed considerable toxicity against distinct Aedes aegypti instars with LC50 values of 44.61 (I instar), 51.27 (II instars), 61.34 (III instars), 72.95 (IV instar), and 89.84 (pupae) μg/mL, respectively. Further, both P. reticulatum extract and AgNPs greatly reduced the survival and reproductive efficiency of A. aegypti adults. Eventually, in conventional laboratory circumstances, the predatory effectiveness of Gambusia affinis against Ae. aegypti II and III instar larvae were 71.35% and 53.40%, respectively. In antibacterial assays, low concentrations of the P. reticulatum synthesized AgNPs inhibited the development of Pseudomonas aeruginosa and Citrobacter freundii. Surface damage, ROS production, and protein leakage are the antibacterial mechanisms of AgNPs. Overall, the lichen‐derived AgNPs can be regarded as newer and safer Ae. aegypti control instruments.
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•Dual-mode security encoding using fluorescence photochromism was developed.•LSAP NPs (25–34 nm) were synthesized and immobilized into CMC hydrogel.•LSAP@CMC anticounterfeiting ...hydrogel was applied toward mapping of fingermarks.•Fingerprints displayed colorless film (365 nm) with green emission (518 nm).•LSAP@CMC hydrogels were tested for their rheological features and printability.
Simple and efficient fluorescent identification of fingerprints without background interferences has been a challenge. Dual-mode security encoding using fluorescence photochromism has been utilized to create very reliable authenticating materials. Herein, lanthanide-doped strontium aluminate phosphor (LSAP) nanoparticles (NPs) were synthesized and immobilized into carboxymethyl cellulose (CMC) hydrogel, which has the potential for low costs, low environmental impact, self-healing and high scale production. We report the development of smart photochromic anticounterfeiting LSAP@CMC hydrogel toward mapping of fingermarks. The photochromic hydrogel was prepared and fingerprinted onto paper surface, displaying a colorless film (365 nm) with green emission (518 nm) under ultraviolet light as verified by CIE Lab and luminescence analyses. The fluorescence security inks were tested for their security features and printability. Both excitation and emission analyses were used to evaluate the optical performance of fingermarks printed onto paper documents. Highly reversible photochromism was detected without fatigue. LSAP nanoparticles were inspected by transmission electron microscope (TEM) to designate diameters of 25–34 nm, whereas the fingermark-printed paper sheets were analyzed by energy-dispersive X-ray (EDX) and scanning electron microscope (SEM). The durability and printability of the LSAP@CMC hydrogel ink were also tested. The rheological behavior of hydrogel and mechanical properties of fingerprints were investigated.
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