Analyzing antibiotic residues in honey samples using liquid chromatography-tandem mass spectrometry.

This study aimed to present a sensitive, accurate, and precise analytical method for the determination of 32 antibiotics from 5 groups (sulfonamides, macrolides, aminoglycosides, tetracyclines, and quinolones) and some individual antibiotics (lincomycin, griseofulvin, and 5-hydroxy-flunixin) in 63 honey samples collected from Tehran market. In the presented method, the samples were hydrolyzed by 1% HFBA (hepta fluoro butyric acid) in water, purified on Strata XL polymeric reversed-phase cartridges, and finally analyzed by reversed-phase ion-pair liquid chromatography-electrospray ionization tandem mass spectrometry (RP-IP-LC-ESI-MS/MS). Good performance characteristics were gained for recovery, precision, range, and linearity, the limit of detections (LODs), and the limit of quantifications (LOQs). According to the presented results and considering the absence of permissible limits for antibiotics in honey, 74.6% of the tested samples had antibiotic residues more than the LOQ of the method. The results show that the validated method is suitable for simultaneously detecting antibiotic residues in honey.

Design, synthesis, and biological evaluation of new 2-(4-(methylsulfonyl)phenyl)-N-phenylimidazo[1,2-a]pyridin-3-amine as selective COX-2 inhibitors.

Cyclooxygenase (COX), which plays a role in converting arachidonic acid to inflammatory mediators, could be inhibited by non-steroidal anti-inflammatory drugs (NSAIDs). Although potent NSAIDs are available for the treatment of pain, fever, and inflammation, some side effects, such as gastrointestinal ulcers, limit the use of these medications. In recent years, selective COX-2 inhibitors with a lower incidence of adverse effects attained an important position in medicinal chemistry. In order to introduce some new potent COX-2 inhibitors, a new series of 2-(4-(methylsulfonyl)phenyl)-N-phenylimidazo[1,2-a]pyridin-3-amines was designed, synthesized, and evaluated. The docking studies performed by AutoDock Vina demonstrated that docked molecules were positioned as well as a crystallographic ligand in the COX-2 active site, and SO2Me pharmacophore was inserted into the secondary pocket of COX-2 and formed hydrogen bonds with the active site. The designed compounds were synthesized through two-step reactions. In the first step, different 1-(4-(methylsulfonyl)phenyl)-2-(phenylamino)ethan-1-one derivatives were obtained by the reaction of aniline derivatives and α-bromo-4-(methylsulfonyl)acetophenone. Then, condensation of intermediates with different 2-aminopyridines gave final compounds. Enzyme inhibition assay and formalin test were performed to evaluate the activity of these compounds. Among these compounds, 8-methyl-2-(4-(methylsulfonyl)phenyl)-N-(p-tolyl)imidazo[1,2-a]pyridin-3-amine (5n) exhibited the highest potency (IC50 = 0.07 µM) and selectivity (selectivity index = 508.6) against COX-2 enzyme (selectivity index: COX-1 IC50/COX-2 IC50). The antinociceptive activity assessment via the formalin test showed that nine derivatives (5a, 5d, 5h, 5i, 5k, 5q, 5r, 5s, and 5t) possessed significant activity compared with the control group with a p value less than 0.05.

Route exposure and adverse effects monitoring of Aflatoxin B1 in the workers of wet waste management, the role of body redox system modulation.

Exposure to dust, containing different fungi metabolites such as aflatoxins is a risk factor for developing liver and kidney health abnormalities. Occupational evaluation of the aflatoxin's exposure-induced health abnormalities should include the monitoring of bioaerosols in the workplace and personal air, and applying of appropriate blood biomarkers to assess Aflatoxin B1 (AFB1) detrimental effects on a worker's health. However, to the best of our knowledge, these appropriate methods, especially determining the associated-adverse effects on health, following exposure, haven't been well documented in the literature at the wet waste handling sites. In the current study, the AFB1 quantity in the area, personal, and settled dust in wet household waste handling samples and AFB1-Albumin levels in the serum of workers in comparison with the control group were determined using high-pressure liquid chromatography with a fluorescent detector (HPLC-FLD) methods. Moreover, the adverse effects of AFB1 on the liver and kidney biochemical profiles of the exposed workers and its relation to antioxidant capacity in the household wet waste sorting were recorded in a consolidated investigation. The results demonstrated that the average airborne dust concentration and its associated AFB1 content were significantly higher in wet waste management sections as compared to the control place, corresponding to the serum AFB1-Albumin levels of workers. Furthermore, AFB1-induced changes in the serum biochemicals evaluating liver and kidney function tests and antioxidant profiles of workers in wet waste handling sections were indicative of their function abnormalities. The results imply AFB1-induced adverse effects on the liver and kidney functions may be mediated through the body redox system modulation.

Overview, consequences, and strategies for overcoming matrix effects in LC-MS analysis: a critical review.

The high-performance liquid chromatography-mass spectrometry (LC-MS) technique is widely applied to routine analysis in many matrices. Despite the enormous application of LC/MS, this technique is subjected to drawbacks called matrix effects (MEs) that could lead to ion suppression or ion enhancement. This phenomenon can exert a deleterious impact on the ionization efficacy of an analyte and subsequently on the important method performance parameters. LC-MS susceptibility to MEs is the main challenge of this technique in the analysis of complex matrices such as biological and food samples. Nowadays, the assessment, estimation, and overcoming of the MEs before developing a method is mandatory in any analysis. Two main approaches including the post-column infusion and post-extraction spike are proposed to determine the degree of MEs. Different strategies can be adopted to reduce or eliminate MEs depending on the complexity of the matrix. This could be done by improving extraction and clean-up methods, changing the type of ionization employed, optimization of liquid chromatography conditions, and using corrective calibration methods. This review article will provide an overview of the MEs as the Achilles heel of the LC-MS technique, the causes of ME occurrence, their consequences, and systemic approaches towards overcoming MEs during LC-MS-based multi-analyte procedures.

Design, synthesis and biological evaluation of novel indanone containing spiroisoxazoline derivatives with selective COX-2 inhibition as anticancer agents.

OBJECTIVE: A new family of 3'-(Mono, di or tri-substituted phenyl)-4'-(4-(methylsulfonyl) phenyl) spiroisoxazoline derivatives containing indanone spirobridge was designed, synthesized, and evaluated for their selective COX-2 inhibitory potency and cytotoxicity on different cell lines. METHODS: A synthetic reaction based on 1,3-dipolar cycloaddition mechanism was applied for the regiospecific formation of various spiroisoxazolines. The activity of the newly synthesized compounds was determined using in vitro cyclooxygenase inhibition assay. The toxicity of the compounds was evaluated by MTT assay. In addition, induction of apoptosis, and expression levels of Bax, Bcl-2 and caspase-3 mRNA in MCF-7 cells were evaluated following exposure to compound 9f. The docking calculations and molecular dynamics simulation were performed to study the most probable modes of interactions of compound 9f upon binding to COX-2 enzyme. RESULTS: The docking results showed that the synthesized compounds were able to form hydrogen bonds with COX-2 involving methyl sulfonyl, spiroisoxazoline, meta-methoxy and fluoro functional groups. Spiroisoxazoline derivatives containing methoxy group at the C-3' phenyl ring meta position (9f and 9g) showed superior selectivity with higher potency of inhibiting COX-2 enzyme. Furthermore, compound 9f, which possesses 3,4-dimethoxyphenyl on C-3' carbon atom of isoxazoline ring, exhibited the highest COX-2 inhibitory activity, and also displayed the most potent cytotoxicity on MCF-7 cells with an IC50 value of 0.03 ± 0.01 µM, comparable with that of doxorubicin (IC50 of 0.062 ± 0.012 µM). The results indicated that compound 9f could promote apoptosis. Also, compared to the control group, the mRNA expression of Bax and caspase-3 significantly increased, while that of Bcl-2 significantly decreased upon exposure to compound 9f which may propose the activation of mitochondrial-associated pathway as the mechanism of observed apoptosis. CONCLUSION: In vitro biological evaluations accompanied with in silico studies revealed that indanone tricyclic spiroisoxazoline derivatives are good candidates for the development of new anti-inflammatory and anticancer (colorectal and breast) agents.

Application of genetic algorithm and multivariate methods for the detection and measurement of milk-surfactant adulteration by attenuated total reflection and near-infrared spectroscopy.

BACKGROUND: The adulteration of milk by hazardous chemicals like surfactants has recently increased. It conceals the quality of the product to gain profit. As milk and milk-based products are consumed by many people, novel analytical procedures are needed to detect these adulterants. This study focused on Fourier-transform infrared (FTIR) spectroscopy equipped with an attenuated total reflection (ATR) accessory, and near-infrared (NIR) spectroscopy for the determination of milk-surfactant adulteration using a genetic algorithm (GA) coupled with multivariate methods. The model surfactant was sodium dodecyl sulfate (SDS), and its concentration varied from 1.94-19.4 gkg-1 in adulterated samples. RESULTS: Prominent peaks in the spectral range of 5500-6400 cm-1 , 1160-1260 cm-1 and 1049-1080 cm-1 may correspond to the sulfonate group in SDS. A genetic algorithm could significantly reduce the number of variables to almost one third by selecting the specific wavenumber region. Principal component analysis (PCA) for ATR and NIR data indicated separate clusters of samples in terms of the concentration level of SDS (P ≤ 0.05). Partial least squares regression (PLSR) was used to determine the maximum R2 value for ATR and NIR data for calibration, cross-validation and prediction, which were 0.980, 0.972, 0.980, and 0.970, 0.937, and 0.956 respectively. The results showed apparent differences between unadulterated and adulterated samples using partial least squares-discriminant analysis (PLS-DA), which was validated by the permutation test. CONCLUSION: The results clearly show the successful application of the proposed methods with multivariate analysis in the selection of variables, classification, clustering, and identification of the adulterant in amounts as low as 1.94 gkg-1 in milk. © 2020 Society of Chemical Industry.

The anti-adhesive and anti-invasive effects of recombinant azurin on the interaction between enteric pathogens (invasive/non-invasive) and Caco-2 cells.

Anti-adhesion therapy and anti-adhesin immunity are meant to diminish the interaction between pathogens and host tissues, either by prevention or by exclusion of bacterial adhesion and entrance to cells. Azurin is a scaffold protein possessing antiviral, antiparasitic, and anticancer activities. The purpose of the present study was to determine the effect of recombinant Azurin (rAzurin) on the adhesion and invasion capacity of invasive (Shigella sonnei, Shigella flexneri, Campylobacter jejuni) and non-invasive (Vibrio cholerae) enteric bacteria to cells. The non-toxic dose of rAzurin and the best MOI (Multiplicity of Infection) of bacterial species was assessed by MTT assay. Bacterial species were used at MOIs of 20:1 and Azurin was applied at the concentrations of 5 and 25 µg/mL and added to Caco-2 cells in competition and replacement assay to assess the anti-adhesion and anti-invasion properties of rAzurin. The protein caused significant decrease in the adhesion rate of S. sonnei, S. flexneri, C. jejuni, and V. cholerae strains to Caco-2 cells by 43, 39, 72, and 38% in competition and 45, 46, 75, and 48% in replacement assays, respectively. Also, S. sonnei, S. flexneri, and C. jejuni strains invasion rate was reduced to 50, 50, and 70% in anti-invasion assay, respectively. The inhibitory effect of Azurin against C. jejuni and V. cholerae strains adhesion was more significant (p < .001) compared to Shigella spp. (p < .05) which may be due to smaller size of the former bacteria. On the contrary, in invasion assay, rAzurin showed a greater inhibitory effect against Shigella spp. (p < .001) compared to C. jejuni (p < .05), which may probably be due to the interaction of rAzurin with several effectors or ligands, involved in Shigella invasion and internalization. The findings of the present study opens new insights of rAzurin as a new and potent candidate for reducing or probably preventing enteric bacterial attachment, invasion, and pathogenesis.

Mitochondria-Targeted Polyamidoamine Dendrimer-Curcumin Construct for Hepatocellular Cancer Treatment.

Mitochondrial malfunction plays a crucial role in cancer development and progression. Cancer cells show a substantially higher mitochondrial activity and greater mitochondrial transmembrane potential than normal cells. This concept can be exploited for targeting cytotoxic drugs to the mitochondria of cancer cells using mitochondrial-targeting compounds. In this study, a polyamidoamine dendrimer-based mitochondrial delivery system was prepared for curcumin using triphenylphosphonium ligands to improve the anticancer efficacy of the drug in vitro and in vivo. For the in vitro evaluations, various methods, such as viability assay, confocal microscopy, flow cytometry, reactive oxygen species (ROS), and real-time polymerase chain reaction analyses, were applied. Our findings showed that the targeted-dendrimeric curcumin (TDC) could successfully deliver and colocalize the drug to the mitochondria of the cancer cells, and selectively induce a potent apoptosis and cell cycle arrest at G2/M. Moreover, at a low curcumin dose of less than 25 µM, TDC significantly reduced adenosine triphosphate and glutathione, and increased the ROS level of the isolated rat hepatocyte mitochondria. The in vivo studies on the Hepa1-6 tumor-bearing mice also indicated a significant tumor suppression effect and the highest median survival days (Kaplan-Meier survival estimation and log-rank test) after treatment with the TDC construct compared to the free curcumin and untargeted construct. Besides its targeted nature and safety, the expected improved solubility and stability represent the prepared targeted-dendrimeric construct as an up-and-coming candidate for cancer treatment. The results of this study emphasize the promising route of mitochondrial targeting as a practical approach for cancer therapy, which can be achieved by optimizing the delivery method.

Liver and kidney serum profile abnormalities in workers exposed to aflatoxin B1 in urban solid waste management centers.

Many workers are exposed to health problems arising from molds, fungi, and their toxins during waste processing. Aflatoxin B1 (AFB1) level in airborne and settled dust, aflatoxin B1-albumin (AFB1-Alb) adduct in serum, liver and kidney biochemical tests, and body redox change of workers in municipal dry waste-processing sites were investigated. The surface, personal, and area air dust and the blood of workers' samples were collected from the plastic and bread waste-sorting sections in three recycling municipal dry waste sites. Digestion (only for serum samples), passed through SPE cartridge, elution, and collection with methanol, immune-affinity column clean-up, and HPLC system equipped with post-column derivatization method and fluorescence detection were performed for determination of AFB1 and AFB1-Alb levels in the samples. The mean level of dust and AFB1 in the personal and area air, and in the settled dust and the AFB1-Alb in the serum of workers in the bread waste sorting, was higher than plastic waste-sorting samples, in all of the sites. The differences in the biochemical profiles of subjects exposed to aflatoxin B1 as compared to the control group especially in liver and kidney function parameters as well as antioxidant factors of the serum were significant. The workers in handling of municipal waste may be exposed to potentially hazardous levels of aflatoxin B1. The adverse effects of AFB1 on the kidney and liver may be caused by changes in the redox system.

Functional mimetic peptide discovery isolated by phage display interacts selectively to fibronectin domain and inhibits gelatinase.

Matrix metalloproteinases (MMPs) play critical roles in a multiple number of autoimmunity diseases progression and metastasis of solid tumor. Gelatinases including MMP-2 and MMP-9 are extremely overexpressed in multiple pathological processes. MMP-9 and MMP-2 breakdown the extracellular matrix component gelatin very efficaciously. Therefore, designing and expansion of MMPs inhibitors can be an engrossing plan for therapeutic intermediacy. Anyway, a wide range of MMPs inhibitors face failure in several clinical trials. Due to sequence and structural conservation across the various MMPs, achieving specific and selective inhibitors is very demanding. In the current study, a phage-displayed peptide library was screened using active human recombinant MMP-9 protein and evaluated by enzyme-linked immunosorbent assay. Here, we isolate novel peptide sequence from phage display peptide libraries that can be a specific gelatinase inhibitor. Interestingly, in silico molecular docking showed strong interactions between the peptide three-dimensional models and some important residues of the MMP-9 and MMP-2 proteins at the fibronectin domain. A consensus peptide sequence was then synthesized (named as RSH-12) to evaluate its inhibitory potency by in vitro assays. Zymography assay was employed to evaluate the effect of RSH-12 on gelatinolysis activity of MMP-2 and MMP-9 secretion from the HT1080 cells using different concentrations of RSH-12 and inhibiting MMP-9- and MMP-2-driven gelatin proteolysis, measured by fluorescein isothiocyanate-gelatin degradation assay and HT1080 cell invasion assay on Matrigel (gelatinous protein mixture). The negative control peptide (CP) with the irrelevant sequence and no MMP inhibition properties and the positive control compound (GM6001) as a potent inhibitor of MMPs were used to assess the selectivity and specificity of gelatinases inhibition by RSH-12. Therefore, RSH-12 decreased the gelatin degradation by specifically preventing gelatin binding to MMP-9 and MMP-2. Selective gelatinase inhibitors may prove the usefulness of the new peptide discovered in tumor targeting and anticancer and anti-inflammation therapies.

Design, synthesis, and biological evaluation of new pyrazino[1,2-a]benzimidazole derivatives as selective cyclooxygenase (COX-2) inhibitors.

A new class of pyrazino[1,2-a]benzimidazole derivatives possessing the SO2 Me pharmacophore at the para position of the C-3 phenyl ring was designed, synthesized, and tested for their cyclooxygenase-2 (COX-2) inhibitory, anti-cancer and anti-platelet aggregation activities. In vitro COX-1/COX-2 inhibition studies showed that 2-(4-methylphenyl)-1-methylene-3-(4-(methylsulfonyl)phenyl)-1,2-dihydropyrazino-[1,2-a]benzimidazole (5g) was the most potent COX-2 inhibitor (IC50 = 0.08 µM) and 2-(3,4,5-trimethoxyphenyl)-1-methylene-3-(4-(methylsulfonyl)phenyl)-1,2-dihydropyrazino-[1,2-a]benzimidazole (5m) had the highest selectivity index (SI > 909). Cytotoxicity of the synthesized compounds was also determined against the MCF-7 cell line. Most compounds were cytotoxic against MCF-7 cells and our results showed that compound 5m exhibited the highest anti-proliferative activity compared to the reference compound, cisplatin. Our data also indicated that compound 5k was the most potent platelet aggregation inhibitor according to aggregometry test results.

DNAzyme-aptamer or aptamer-DNAzyme paradigm: Biochemical approach for aflatoxin analysis.

DNAzyme and aptamer conjugations have already been used for sensitive and accurate detection of several molecules. In this study, we tested the relationship between conjugation orientation of DNAzyme and aflatoxin B1 aptamer and their subsequent peroxidase activity. Circular dichroism (CD) spectroscopy and biochemical analysis were used here to differentiate between these two conjugation patterns. Results showed that DNAzyme-aptamer has more catalytic activity and efficiency than aptamer-DNAzyme. Thereby, DNAzyme-aptamer with its superior efficiency can be used for design and development of more sensitive aflatoxin B1 DNA based biosensors.

Design, Synthesis, and Biological Evaluation of New Peptide Analogues as Selective COX-2 Inhibitors.

A new class of peptide derivatives possessing SO2 Me and N3 pharmacophores at the para position of a phenyl ring bound to different aromatic amino acids were synthesized based on solid-phase synthesis methodology, and evaluated as selective cyclooxygenase-2 (COX-2) inhibitors. One of the analogues, i.e., compound 2a as the representative of this series, was recognized as the highest selective COX-2 inhibitor with a COX-2 selectivity index of >500. The structure-activity relationships (SARs) acquired indicated that compound 2a containing a 4-(methylsulfonyl)benzoyl group as a pharmacophore and tyrosine as a ring bearing amino acid in the second position and glutamic acid as the C-terminal amino acid can give the essential geometry to provide selective COX-2 inhibitory activity. Antiproliferative activity of the synthesized peptides (1a-7b) was also determined against four different human cancer cell lines, including MCF-7, HepG2, A549, and HeLa. According to our results, A549, HepG2, and MCF7 seemed to be more sensitive cell lines than HeLa cells encountering these compounds, which gave inhibitory action with IC50 values from 4.8 to 64.4 µM. In this regard, compounds 3a and 2b displayed the best inhibitory activity against the cell lines. Moreover, a good correlation was observed between the antiproliferative potency and the COX-2 inhibitory activity of compounds 1a, 2a, 2b, and 5b. Such findings suggest that one of the mechanism of anticancer activity of these peptides may be through the COX-2 inhibitory action.

Design, Synthesis, Docking Studies, Enzyme Inhibitory and Antiplatelet Aggregation Activities of New 1,3-Diphenyl-3-(Phenylthio)Propan-1-One Derivatives as Selective COX-2 Inhibitors.

BACKGROUND: Cancer is the second leading cause of death worldwide after heart disease. A vast number of studies indicated that selective cyclooxygenase-2 (COX-2) inhibitors could be chemopreventive against different types of cancer because the expression of COX-2 is increased. Therefore, to develop new therapeutics for cancer, the design and synthesis of new COX-2 inhibitors with few side effects seem attractive as anti-cancer agents. OBJECTIVE: Some of the well-known drugs that have been widely used for some time have been removed from the market due to the cardiac side effects they cause, so there is a need to introduce a scaffold that can inhibit COX-2 with high potency and low side effects. This study aimed to introduce a new COX-2 inhibitor structure. METHODS: A new series of ß-aryl-ß-mercapto ketones possessing a methylsulfonyl pharmacophore was synthesized and evaluated as selective COX-2 inhibitors. In-vitro COX-1 and COX-2 inhibition effects of these compounds were evaluated, and molecular modeling was examined. Also, the antiplatelet aggregation activity of the synthesized compounds was tested. RESULTS: In-vitro COX-1 and COX-2 inhibition assays indicated that almost all newly synthesized compounds showed selectivity for COX-2 with IC50 values in the 0.07-0.22 µM range and COX-2 selectivity indexes in the 170 to 703.7 range. Among the tested compounds 1-(4-(methylsulfonyl)phenyl)-3-phenyl-3-(phenylthio)propan-1-one (4a), 3-(3,4- dimethoxyphenyl)-1-(4-(methylsulfonyl)phenyl)-3-(phenylthio)propan-1-one (4g) and 3-(4-fluorophenyl)-1-(4-(methyl sulfonyl)phenyl)-3-(phenylthio)propan-1-one (4h) were the most potent COX-2 inhibitors and 3-(3,4- dimethoxyphenyl)-1-(4-(methylsulfonyl)phenyl)-3-(phenylthio)propan-1-one had the highest selectivity index for COX-2 enzyme inhibitory activity. The Anti-platelet aggregation activity results indicated that the compound 1-(4- (methylsulfonyl)phenyl)-3-(phenylthio)-3-(p-tolyl)propan-1-one (4b) possesses the strong anti-platelet activity. Our molecular modeling studies also indicated that the methylsulfonyl pharmacophore group is placed into the adjunct pocket in the COX-2 active site and forms hydrogen bond interactions with NH of Arg513 and NH of His90. CONCLUSION: In brief, all designed and synthesized compounds showed moderate to good COX-2 inhibitory effects and showed good anti-platelet activity. Therefore, these compounds have the potential for further research into developing anti-cancer agents.

Multivariate Optimization and Validation of a Modified QuEChERS Method for Determination of PAHs and PCBs in Grilled Meat by GC-MS.

Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) are recognized as carcinogens and mutagenic food contaminants that threaten public health. As for food safety aspects, control of these contaminants in processed and fatty food is necessary. In this study, eleven factors were screened by the Plackett-Burman design, and four variables were chosen to optimize with the central composite design (CCD) for the improvement of extraction and cleanup procedures of these food contaminants. The optimized variables include 5 g of sample, 2 mL mixture of 2/2/1 ethyl acetate/acetone/isooctane, 1.6 g of ammonium formate, 0.9 g of sodium chloride, and 0.25 g of sorbent Z-Sep+. A 5 min cleanup vortex time with the spike calibration curve strategy, analyzed by gas chromatography-mass spectrometry (GC-MS), led to the validated limits of quantification (LOQs) for 16 PAHs and 36 PCBs of 0.5-2 and 0.5-1 ng/g, respectively, and recoveries of 72-120%, with an average relative standard deviation (%RSD) of 17, for PAHs, and 80-120%, with an %RSD of 3, for PCBs. The method introduces excellent accuracy, precision, and efficiency, and minimizes matrix effects, and ensures a control procedure, adopted with international standards, for food authorities to determine the contaminants of interest in processed meat, and consequently, prevent food-borne disease to improve public health indices.

Hybrid Analogues of Hydrazone and Phthalimide: Design, Synthesis, In vivo, In vitro, and In silico Evaluation as Analgesic Agents.

BACKGROUND: Based on the anti-inflammatory and analgesic activity of hydrazone and phthalimide, a new series of hybrid hydrazone and phthalimide pharmacophores was prepared and evaluated as analgesic agents. METHODS: The designed ligands were synthesized by reaction of the appropriate aldehydes and 2- aminophthalimide. Analgesic, cyclooxygenase inhibitory, and cytostatic activity of prepared compounds were measured. RESULTS: All the tested ligands demonstrated significant analgesic activity. Moreover, compounds 3i and 3h were the most potent ligands in the formalin and writhing tests, respectively. Compounds 3g, 3j, and 3l were the most COX-2 selective ligands and ligand 3e was the most potent COX inhibitor with a 0.79 of COX-2 selectivity ratio. The presence of electron-withdrawing moieties with hydrogen bonding ability at the meta position was found to affect the selectivity efficiently, in which compounds 3g, 3l, and 3k showed high COX-2 selectivity, and compound 3k was the most potent one. The cytostatic activity of selected ligands demonstrated that compounds 3e, 3f, 3h, 3k, and 3m showed good analgesic and COX inhibitory activity and were less toxic than the reference drug. CONCLUSION: High therapeutic index of these ligands is one of the valuable advantages of these compounds.

Application of the oxycodone templated molecular imprinted polymer in adsorption of the drug from human blood plasma as the real biological environment; a joint experimental and density functional theory study.

In this project, we have synthesized and used a molecular imprinted polymer (MIP) for adsorption of oxycodone residue from the biological samples. Indeed, this study aims to develop a suitable method for determination of oxycodone drug residue in the human plasma using the common analysis methods. Therefore, the MIP was used for the solid phase extraction (MIP-SPE) approach in order to collect the oxycodone opioid and to concentrate it in the blood plasma samples. The extraction parameters such as adsorption time, pH, and the amount of sorbent in blood plasma were optimized and the capacity of loading amount (LA) for adsorbing it was determined. Moreover, a high performance liquid chromatography (HPLC)-UV detector method was validated and used for analyzing of the mentioned opioid extracted from plasma. The results showed that the limit of detection (LOD), and the limit of quantization (LOQ) for the developed MIP-SPE method were 1.24 ppb, and 3.76 ppb, respectively. Moreover, both of the MIP-, and non-imprinted polymers (NIP)-drug complexes were designed and were then optimized by the density functional theory (DFT) method. The results showed that the theoretical calculations supported the experimental data, confirming the favorability of adsorption of the drug by MIP compared to NIP.

Simultaneous Analysis and Efficient Separation of Anabolic Androgenic Steroids in Dietary Supplement by a Validated HPTLC Method.

Background: Using sports supplements is common among athletes. The presence of anabolic steroids in sports supplements as a hormonal contaminant can increase production efficiency. Since anabolic steroids cause health problems and result in positive doping tests in athletes, it is important to investigate their presence in the supplement preparations consumed by athletes. Objectives: This paper aims to simultaneously determine ten anabolic steroids by high-performance thin-layer chromatography (HPTLC) method in sports supplements. Methods: Chromatographic analysis was conducted on glass silica gel 60F254 plates. The extracts loaded on silica gel plates are subjected to programed multiple development (PMD) to separate anabolic androgenic steroids (AASs). Densitometric scanning is carried out at the wavelength of 245 and 366nm. The method was validated according to the ICH guidelines. Results: Spots at retardation factor (Rf) 0.72 (elution system 1), 0.4 (elution system 1), 0.29 (elution system 2), 0.25 (elution system 2), 0.1 (elution system 1), 0.65 (elution system 2), 0.59 (elution system 1), 0.44 (elution system 1), 0.8 (elution system 3), and 0.82 (elution system 3) values were recognized as 19-nor androstenedione, 19-nortestosterone, methyl testosterone, clostebol, stanozolol, trenbolone enanthate, oxymetholone, oxandrolone, testosterone enanthate, and nandrolone decanoate, respectively. The linear ranges were 25 - 250 µg/mL for oxymetholone, 7 - 50 µg/mL for 19-nor androstenedione, 19-nortestosterone, and oxandrolone, and 3 - 20 µg/mL for methyl testosterone, clostebol, stanozolol, trenbolone enanthate, testosterone enanthate, and nandrolone decanoate. The developed method is validated by acceptable precision (CV < 20%) and good accuracy (94% < R < 114%). The value of limit of detection (LOD) for all derivatives was in the range of 0.02 - 0.16 µg/spot (20-160 µg/g of supplement), while limit of quantitation (LOQ) was found to be in the range of 0.06 - 0.5 µg/spot (60 - 500 µg/g of supplement). Fifty sports supplement samples as real sample were collected and analyzed. None of the samples screened positive using the HPTLC method. Conclusions: In the present study, the fast, cheap, and simple HPTLC method could be used for the multi-residue analysis of ten anabolic androgenic steroids in sports supplements.

Synthesis, evaluation of drug delivery potential, and the quantum chemical investigation on a molecular imprinted polymer for quetiapine antipsychotic; a joint experimental and density functional theory study.

In this project, the quetiapine drug was used as the template for synthesis of a molecular imprinted polymer (MIP). The polymerization approach for preparation of this composite was precipitation, where methacrylic acid (MAA), ethylene glycol dimethacrylate (EGDMA), and 2,2-azobisissobutyronitrile (AIBN) were used as the functional monomer, the cross-linker, and the initiator, respectively. Scanning electron microscopy (SEM) showed that the diameter of the nanoparticles is about 70 nm. The adsorption rates of quetiapine to the MIP host were evaluated at different pHs, and the results showed that the highest adsorption values were obtained at pH = 7. Moreover, the kinetics of the adsorption process was detected to follow the Langmuir isotherm (R2 = 0.9926) and the pseudo-second-order kinetics (R2 = 0.9937). The results confirmed the high capability of the synthesized MIPs as pharmaceutical carriers for quetiapine. Furthermore, the kinetics of the drug release from the MIP follows the Higuchi model at the pHs of 5.8-6.8 and the Korsmeyer-Peppas model at the pHs of 1.2-5. Finally, in light of the density functional theory (DFT)-based quantum chemical descriptors, the polymer-quetiapine drug complex was designed and investigated. The results showed that there is a strong interaction between the host (polymer) and the guest (drug) due to several hydrogen bonds and other intermolecular (polar) interactions.

A Neglected Challenge in the Analysis of Active Pharmaceutical Substances with Aldehyde Functional Group in Aqueous Matrices.

Aldehydes are compounds that are widely used and popular in organic synthesis due to their high reactivity. This advantage is a disadvantage in medicinal chemistry. Due to the ability of aldehydes to participate in nucleophilic reactions (especially in aqueous biological media) and access to nucleophiles such as amino acids and nucleic acids, drugs with aldehyde functional groups are always used with caution and carefully quantified in biological fluids. Our experience in working on biologically active aldehydes indicates the transformation of these groups of compounds in aqueous or alcoholic solution and thus the failure of analytical methods for their accurate monitoring in such media. Both mass spectrometry and Proton nuclear magnetic resonance spectroscopic findings indicate the reaction of spiramycin with water molecules in an aqueous solution, resulting in the conversion of spiramycin to a new molecule with 18 mass unit difference and thus, the residue amount which is measured and reported based on a mass spectrometries method does not show the correct amount of spiramycin in these samples.