Development of sensitive spectrofluorometric approach based on formation of pyrrolidone derivative for determination of linagliptin through condensation reaction with ninhydrin and phenylacetaldehyde: Application to content uniformity and real plasma.

The new drug linagliptin belongs to the class of dipeptidyl peptidase-4 enzyme inhibitors. Linagliptin is used to treat type 2 diabetes and is taken orally either alone or in combination with other drugs. In this instance, a new, simple, and economical technique for analyzing linagliptin was developed by the effective use of a pyrrolidone derivative. The primary amine group of linagliptin permits its condensation with ninhydrin (0.14% w/v) to produce a fluorescent product in the presence of phenylacetaldehyde (0.02% v/v). All experimental parameters were carefully examined and adjusted in order to monitor the generation of the pyrrolidone derivative at excitation and emission wavelengths of 385 and 475 nm, respectively. The calibration graph was made by plotting the intensity of the fluorescence in relation to linagliptin concentration. A significant linearity was found for values ranging from 20 to 460 ng/mL. The process's validity has been verified by a thorough assessment of the instructions provided by the International Conference on Harmonization (ICH). The results indicate excellent uniformity with a reference method, showing that there is no substantial difference in precision and accuracy. The proposed approach was utilized for determining linagliptin in real rat plasma successfully owing to its high sensitivity. Additionally, the proposed approach was evaluated using the Eco-Scale evaluation tool and showed a high degree of eco-friendliness (86/100).

In vitro and In silico assessment of antischistosomal activities of ethanolic extract of Cornulacamonacantha.

Schistosomiasis is the second most prevailing parasitic disease worldwide. Although praziquantel is considered an effective drug in the treatment against schistosomiasis to some extent, there is an emerging drug resistance that widely recorded. Therefore, there is an urgent need to develop effective and safe anti-schistosomal drugs. In this study, Cornulaca monacantha (C. monacantha), a sub-saharan plant, was extracted using aqueous ethanol and characterized by High-Performance Liquid Chromatography (HPLC). Major constituents of the extract are belonging to flavonoids, tannins and phenolic glycosides. Worms' viability and surface morphology of Schistosoma mansoni (S. mansoni) adult worms treated with the extract were assessed using in vitro viability assay, Scanning Electron Microscopy (SEM), and histological examination. The extract (80-350 µg/ml) reduced viability percentage of worms by 40-60% and caused degeneration of both oral and ventral suckers, tegumental, sub-tegumental and muscular damage. Molecular docking approach was utilized to assess the binding affinities of the extracted compounds with S. mansoni alpha-carbonic anhydrase (SmCA), an essential tegument protein. Pharmacokinetic analysis using SwissADME showed that 7 compounds have high drug similarity. This study confirms the in vitro schistomicidal activity of C. monacantha extract against S. mansoni adult worms and suggests potential SmCA inhibition.

Hematological, biochemical, genotoxic, and histopathological changes induced by pyridaben.

The current work examined the genotoxic effects of pyridaben (PDB) in male Sprague Dawley rats. Twenty Sprague Dawley rats were divided into four equal groups; the first group was used as a control group; the other three groups were exposed to 19, 28.5, and 57 mg/kg b.w PDB by oral gavage for 4 weeks. Blood samples were collected for hematological and biochemical parameters; femoral bone marrow was flushed for chromosomal aberrations (CA) assay and liver samples were used for the analysis of gene expression of IL-6 and Casp-3 as well as histopathological and immunhistochemical investigation for Casp-3. The results showed that PDB exposure lead to non-significant changes in hematological parameters in all PDB administrated groups while malondialdehyde, glutathione peroxidase, aspartate aminotransferase, and alkaline phosphatase were significantly increased in 19 and 57 mg/kg PDB doses groups Also, gene expression of IL-6 and Casp-3 revealed a significant increase in 28.5 and 57 mg/kg PDB doses groups as compared with the control. However, there was no significant change in the percentage of CAs in bone marrow cells in all PDB-exposed groups. The histopathological and immunhistochemical examination showed focal areas of inflammatory cellular infiltration with fibrosis in 57 mg/kg b.w PDB dose group accompanied by the severe positive reaction of caspase3 in the liver.

Zinc(II) complexation strategy for ultra-sensitive fluorimetric estimation of molnupiravir: Applications and greenness evaluation.

The endemicity of the pandemic coronavirus disease 2019 (COVID-19) infection proved to be transitional only. Spikes are forming again in 2023, and high expectations are returning for reinfections and viral mutations. Molnupiravir (MOL) has been approved as an oral antiviral drug for the treatment of the COVID-19 causative virion. Therefore, the development of an ultrasensitive, instantaneous, and cost-effective method for the quantification of MOL in real plasma samples and formulated dosage form are mandatory. The proposed approach is based on the synthesis of a MOL metal-chelation product. MOL as a ligand was chelated with 1.0 mM zinc(II) in an acetate buffer (pH 5.3). After illumination at 340 nm, the intensity of the MOL fluorescence measured at 386 nm was increased by about 10-fold. The linearity range was found to be from 60.0 to 800.0 ng mL-1 with limit of quantitation (LOQ) of 28.6 ng mL-1 . Two methods were utilized for measuring the greenness of the proposed method (Green Analytical Procedure Index [GAPI] and analytical greenness metric [AGREE] methods), with results equal to 0.8. The binding stoichiometry of MOL with the zinc(II) ion was found to be 2:1. All the experimental parameters were optimized and validated using International Conference on Harmonization (ICH) and United States Food and Drug Administration (US-FDA) recommendations. Furthermore, the fluorescent probes were successfully utilized in real human plasma with high percentages of recovery (95.6%-97.1%) without any matrix interferences. The mechanism of fluorescent complex formation was confirmed using 1 H NMR in the presence and absence of Zn(II). The method was further utilized for testing content uniformity of MOL in its marketed capsule dosage forms.

An Innovative Polymer-Based Electrochemical Sensor Encrusted with Tb Nanoparticles for the Detection of Favipiravir: A Potential Antiviral Drug for the Treatment of COVID-19.

An innovative polymer-based electro-sensor decorated with Tb nanoparticles has been developed for the first time. The fabricated sensor was utilized for trace determination of favipiravir (FAV), a recently US FDA-approved antiviral drug for the treatment of COVID-19. Different techniques, including ultraviolet-visible spectrophotometry (UV-VIS), cyclic voltammetry (CV), scanning electron microscope (SEM), X-ray Diffraction (XRD) and electrochemical impedance spectroscopy (EIS), were applied for the characterization of the developed electrode TbNPs@ poly m-THB/PGE. Various experimental variables, including pH, potential range, polymer concentration, number of cycles, scan rate and deposition time, were optimized. Moreover, different voltammetric parameters were examined and optimized. The presented SWV method showed linearity over the range of 10-150 × 10-9 M with a good correlation coefficient (R = 0.9994), and the detection limit (LOD) reached 3.1 × 10-9 M. The proposed method was applied for the quantification of FAV in tablet dosage forms and in human plasma without any interference from complex matrices, obtaining good % recovery results (98.58-101.93%).

NiFe-based Prussian blue analogue nanopolygons hybridized with functionalized glyoxal polymer as a voltammetric platform for the determination of amisulpride in biological samples.

A novel voltammetric platform based on pencil graphite electrode (PGE) modification has been proposed, containing bimetallic (NiFe) Prussian blue analogue nanopolygons decorated with electro-polymerized glyoxal polymer nanocomposites (p-DPG NCs@NiFe PBA Ns/PGE). Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and square wave voltammetry (SWV) were utilized to investigate the electrochemical performance of the proposed sensor. The analytical response of p-DPG NCs@NiFe PBA Ns/PGE was evaluated through the quantity of amisulpride (AMS), one of the most common antipsychotic drugs. Under the optimized experimental and instrumental conditions, the method showed linearity over the range from 0.5 to 15 × 10-8 mol L-1 with a good correlation coefficient (R = 0.9995) and a low detection limit (LOD) reached, 1.5 nmol L-1, with excellent relative standard deviation for human plasma and urine samples. The interference effect of some potentially interfering substances was negligible, and the sensing platform demonstrated an outstanding reproducibility, stability, and reusability. As a first trial, the proposed electrode aimed to shed light on the AMS oxidation mechanism, where the oxidation mechanism was monitored and elucidated using the FTIR technique. It was also found that the prepared p-DPG NCs@NiFe PBA Ns/PGE platform had promising applications for the simultaneous determination of AMS in the presence of some co-administered COVID-19 drugs, which could be attributed to the large active surface area, and high conductivity of bimetallic nanopolygons.

Ultrasensitive green spectrofluorimetric approach for quantification of Hg(II) in environmental samples (water and fish samples) using cysteine@MnO2 dots.

Mercury (Hg2+ ) is a natural element present in foods such as fish, water and soil. Exposure to mercury leads to severe toxic effects on the nervous, digestive, and immune systems. Here, a novel, green, and environmentally friendly fluorescent probe decorated with cysteine/MnO2 quantum dots (Cys@MnO2 QDs) was synthesized. This synthesis was carried out using a simple ultrasound technique with the aid of cysteine for fabricating Cys@MnO2 QDs to estimate Hg levels in fish and water samples. In this morphological study, Cys@MnO2 QDs were fully characterized using high-resolution transmission electron microscopy, zeta potential analysis, fluorescence, ultraviolet-visible and infrared spectroscopy. The fluorescence of the synthesized Cys@MnO2 QDs was significantly quenched by gradually increasing the Hg(II) concentration. The quenching mechanism based on the Hg-S bonds strengthened the utility of the Cys@MnO2 QDs as a novel luminescent nanoprobe. The estimation of Hg was linear in the concentration range 0.7-100.0 ng mL-1 with a limit of quantitation equal to 0.30 ng mL-1 . The Cys@MnO2 QDs are fluorescent probes with various benefits such as speed, ease of use, cost- effective, and being environmentally friendly; they are easily applied in food manufacturing and for public health improvement.

The role of sodium lauryl sulfate on formulation of directly compressed tablets containing simvastatin and aspirin: Effect on drugs dissolution and gastric mucosa.

According to the American College of Cardiology/American Heart Association (ACC/AHA), both aspirin and statin are used in the primary prevention of cardiovascular diseases. Aspirin (ASA) is contraindicated if there is gastrointestinal bleeding because it will exaggerate the condition. In this study, the effect of surfactant; sodium lauryl sulfate (SLS), in enhancing the in vitro dissolution of simvastatin (SIM) and ASA, as well as gastric irritation and upset, was studied. Oral tablets containing both ASA and SIM with and without the SLS were manufactured using the direct compression technique. The prepared tablets were characterized with respect to hardness, friability, uniformity of dosage units, in vitro disintegration, and dissolution. The effect of the addition of SLS in reducing the in vivo irritation and protection of gastric mucosa were also investigated. The results showed that the compressed tablets possessed sufficient hardness, acceptable friability, and are uniform with respect to disintegration, drugs contents, and tablet weight. The results showed that SIM alone exhibited a gastroprotective effect on the induced irritation. In addition, the incorporation of the SLS in the tablets containing SIM and ASA significantly enhanced the dissolution rates of both drugs and significantly decreased the gastric irritation and the ulcer index. The ulcer index of aspirin was decreased from 2.3 for tablets manufactured without SLS to 0.8 for tablets containing SLS. In a conclusion, the addition of pH modifier surfactant; SLS could enhance the dissolution rate of poorly soluble acidic drugs, reduce gastric upset and irritation without any effect on the main characters of the tablets. Moreover, the addition of SLS is very useful in improving the therapeutic activities and reducing the side effects of ASA and SIM for patients who require long-term administration of these drugs.

Emphasis on the incorporation of Tropaeolin OO dye and silver nanoparticles for voltammetric estimation of flibanserin in bulk form, tablets and human plasma.

A novel electrochemical sensor based on the electro-deposition of silver nanoparticles (AgNPs) on Tropaeolin OO (poly-TO) layers over pencil graphite electrode (PGE) surface was fabricated for the first time for voltammetric determination of flibanserin (FBS); a drug enhances female sexual performance. Further characterization studies using cyclic voltammetry (CV), square wave voltammetry (SWV), electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) were conducted. The AgNPs synergistic effect on poly-TO layers facilitates the FBS electro-oxidation in phosphate buffer solution (pH 6.0) and its determination in bulk form, tablets and in human plasma. Following ICH guidelines, validation of the proposed SWV method for FBS analysis was successfully achieved using the fabricated sensor (AgNPs@poly-TO/PGE). Under the optimal instrumental and experimental conditions, the anodic oxidation peak current was directly proportional to FBS concentration in the range from 0.1 to 8.5 µmol L-1 with low detection and quantitation limits (0.0286 and 0.0867 µmol L-1, respectively). High sensitivity, selectivity as well as easiness of fabrication are the main advantages of the modified sensor.

Reproductive effects of sulfoxaflor in male Sprague Dawley rats.

The study objective was to evaluate the potential reproductive toxicity of sulfoxaflor (SFX) insecticide in male Sprague Dawley rats. To attain these objectives, forty male Sprague Dawley rats of 10-12 weeks old were randomly divided into four equal groups; the 1st group was used as a control group; the other three groups were exposed to 25, 100, and 500 mg/kg body weight SFX by oral gavage for 4 weeks. Relative testicular weight, testosterone, FSH, LH, MDA, and GPx levels, sperm viability, sperm morphology, sperm DNA damage, and histopathological changes in testes, epididymis, and seminal vesical of these rats were investigated after 4 weeks. The results showed that SFX exposure resulted in a significant increase in FSH, LH, MDA, and GPx levels as well as the percentage of dead and abnormal sperms and DNA damage in rat sperms. Histopathological examination of testes established testicular degeneration with coagulative necrosis as well as the proliferation of interstitial connective tissue infiltrated with inflammatory cells with congestion of intertubular blood vessels in epididymis and degeneration of lining epithelium of seminal vesicles.

Effect of l-carnitine supplementation on lead acetate-induced liver cell apoptosis and inflammation: role of caspase-3 and glycogen synthase kinase-3ß enzymes.

AIM: The study aimed at studying the hepatoprotective effect of l-carnitine against lead (Pb) acetate-induced hepatocellular injury, emphasizing the role of caspase-3 and glycogen synthase kinase-3ß in hepatocellular apoptosis and inflammation. MATERIALS AND METHODS: Male Wistar rats were used. The experimental approach involved estimation of the liver enzymes' serum levels. Oxidative and inflammatory biomarkers were measured in hepatic tissue homogenates. Paraffin-embedded hepatic sections were prepared for histopathology and immunohistochemistry. Quantitative determination of the phosphorylated glycogen synthase kinase-3 beta was performed. KEY FINDINGS: The serum showed a significant elevation in ALT, AST, and LDH; tissue homogenates showed significant elevation in lipid peroxide and inflammatory biomarkers with significant reduction in reduced glutathione in the Pb acetate-treated group. Co-administration of l-carnitine with Pb acetate produced significant reduction in liver enzymes with significant improvement in oxidant, antioxidant and inflammatory markers. Lead acetate treatment significantly reduced the phosphorylated glycogen synthase kinase-3 beta, while l-carnitine enhanced its phosphorylation. Histopathological examination showed inflammatory reaction around blood vessels with fatty degeneration in hepatocytes of the Pb acetate intoxicated group. l-Carnitine caused a decrease in hepatic damage with minimal vascular alterations in central vein. Caspase-3 expression in hepatocytes was decreased in Pb-treated group supplemented with l-carnitine. SIGNIFICANCE: Our study reveals that oxidative stress and inflammation participate in Pb acetate-induced hepatocellular injury. Glycogen synthase kinase-3ß and caspase-3 play role in Pb acetate-induced hepatic damage. l-Carnitine shows significant protective effects against hepatocellular apoptosis and inflammation induced by Pb acetate through antioxidant, anti-inflammatory and anti-apoptotic pathways in part mediated by GSK-3ß inhibition.

A bio-analytically validated HPLC-UV method for simultaneous determination of doripenem and ertapenem in pharmaceutical dosage forms and human plasma: a dual carbapenem regimen for treatment of drug-resistant strain of Klebsiella pneumoniae.

The emergence of strains resistant to certain antibiotics is turning into an important issue worldwide that threatens global health with the increasing incidence of carbapenemase-producing Klebsiella pneumoniae (KPC). Thus, successful doripenem-ertapenem (DOR-ERTA) combination is highly recommended in treatment of bacteremic ventilator-associated pneumonia due to Klebsiella pneumoniae. Hence, a fast and highly-sensitive HPLC-UV method was developed for the estimation of the cited drugs simultaneously in their pure form, pharmaceutical dosage forms and in simulated synthetic mixtures. The DOR-ERTA mixture was successfully separated within 6 min on a reversed-phase ODS column using an isocratic elution; a mobile phase mixture consists of 0.05 M phosphate buffer (pH 3.0 adjusted by 85% ortho-phosphoric acid) : acetonitrile : methanol (86 : 12 : 2; % v/v/v). The proposed method was optimized and validated according to ICH guidelines, where the calibration graph was constructed from 0.04 to 50 µg mL-1 and from 0.05 to 50 µg mL-1 with low detection limits reached 1.7 and 1.4 ng mL-1 for DOR and ERTA respectively. The proposed method showed higher sensitivity than several previous methods, which allowed an effective estimation of the DOR and ERTA in human plasma after a simple extraction method with high recovery results ranged from 96.30% ± 1.55 to 97.90% ± 1.45 and without any interference from plasma components.

Vaginal suppositories of cumin seeds essential oil for treatment of vaginal candidiasis: Formulation, in vitro, in vivo, and clinical evaluation.

Fungal infections by resistant Candida species continue to be a significant health problem. Novel antifungal agents such as essential oils of cumin seeds (EOCS) are tested against vulvovaginal candidiasis (VVC). The aim of this study was to develop coated polyethylene glycol (PEG) vaginal suppositories containing EOCS for treatment of VVC. PEG suppositories containing EOCS were prepared ppearance, weight variation, drug content, hardness, dissolution time, release, stability and anticandida activity were evaluated. Biocompatibility of selected formulation was tested in female rabbits, followed by clinical evaluation. Coated suppositories showed complete release of the oil after 30 min, in vitro anti-candida activity, enhanced stability and sufficient safety on the vaginal tissues of rabbits. Clinical results showed significant lower rates of vaginal itching, discharge and dyspareunia combined with negative cultures in 70% of patients, revealing efficacy of EOCS-containing vaginal suppositories for treatment of VVC.

Surgical castration versus chemical castration in donkeys: response of stress, lipid profile and redox potential biomarkers.

BACKGROUND: Castration is a husbandry practice raising important questions on the welfare and physiological status of farm animals. Searching for effective castration methods that minimally compromise the body physiology is worthy of attention. Therefore, this study aimed to evaluate the differential response of biological systems in donkeys to surgical castration versus the chemical one by CaCl2 with special emphasis on stress, lipid profile, and oxidative stress biomarkers. Donkeys were divided randomly and equally into two groups; the chemical (Ch) and surgical (S) groups (n = 6). The Ch group was chemically castrated by intratesticular injection of 20% CaCl2 dissolved in absolute ethanol. Blood samples were collected prior to castration and at 15, 30, 45, and 60 days after the beginning of experiment. RESULTS: Surprisingly, the Ch group at the end of the experiment was characterized by significantly higher cortisol level compared to the S group. TC and LDL-C levels in the S group significantly decreased at day 45, while TG levels significantly increased at days 45 and 60 in comparison with day 0. HDL-C levels at days 30 and 60 in the Ch group significantly increased in comparison with day 0. At day 30 post-castration, HDL-C was significantly higher and LDL-C was significantly lower in the Ch group than the S group. A significant elevation in TC and LDL-C was observed at day 45 and in HDL-C at the end of experimental duration in the Ch group when compared with the S group. TPX level was significantly lower and TAC was significantly higher in the Ch group at day 45 than the S group. CONCLUSION: Surgical castration evoked less stress and minor changes in lipid profile and oxidant/antioxidant balance relative to chemical castration by intratesticular 20% CaCl2 dissolved in absolute ethanol.

A selective and highly sensitive high performance liquid chromatography with fluorescence derivatization approach based on Sonogashira coupling reaction for determination of ethinyl estradiol in river water samples.

A selective and highly sensitive high performance liquid chromatography (HPLC) with fluorescence derivatization method was developed for determination of ethinyl estradiol (EE); one of endocrine-disrupting compounds (EDCs). The fluorescence derivatization procedure was based on Sonogashira coupling reaction using 4-(4, 5-diphenyl-1H-imidazole-2-yl) iodobenzene (DIB-I), a fluorescence labeling reagent, to derivatize EE in presence of copper and palladium ions. The formed fluorescent product was separated on Cosmosil 5C18 MS-II by an isocratic elution with a mobile phase composed of acetonitrile: 5.0 mM Tris-HNO3 buffer, pH 7.4 (60:40, v/v %). The detection wavelengths were set at 310 and 400 nm as excitation and emission wavelengths, respectively. Various parameters affecting derivatization reaction were optimized. Further, the proposed method was validated and a good linearity with low detection limit (S/N=3) 7.4 ng L-1 was obtained in water sample after a simple solid-phase disk extraction (C18 SPE disk) method. The proposed method was successfully applied for detection of EE in river water samples in order to monitor EE concentration and to distinguish its effect on the ecosystem and human health.

Applicability of ninhydrin as a fluorescent reagent for estimation of teicoplanin in human plasma using salting-out assisted liquid-liquid extraction technique.

The applicability of ninhydrin, a widely used derivatizing reagent, for determination of teicoplanin (TEIC) in its pure form, pharmaceutical vials, and in human plasma was investigated. The presented spectrofluorimetric method was based on a condensation reaction between ninhydrin and the primary amine group existing in TEIC (in the presence of phenylacetaldehyde) to produce a highly fluorescent product detected at 460 nm (λex ,390 nm). Calibration plots were constructed in the concentration range 60-600 ng mL-1 with a good correlation coefficient of 0.9998 and a low detection limit of 10.84 ng mL-1 . The method was subjected to a bioanalytical validation study according to US-FDA recommendations. The proposed method was applied for analysis of TEIC in commercial vials with high recovery result 101.88 ± 1.11%. In addition, the method was utilized efficiently for detection of TEIC in human plasma using salting-out assisted liquid-liquid extraction technique (SALLE) with a recovery range from 96.71 ± 1.08% to 97.71 ± 0.86%. SALLE is an effective approach used for extraction of TEIC from human plasma without interferences using ammonium sulphate. The proposed method is highly recommended to monitor TEIC in clinical laboratory samples and therapeutic drug monitoring systems.

Development of HPLC method for estimation of glyoxylic acid after pre-column fluorescence derivatization approach based on thiazine derivative formation: A new application in healthy and cardiovascular patients' sera.

Glyoxylic acid (GA) is the intermediate metabolite in various mammalian metabolic pathways. GA showed high reactivity towards formation of advanced glycation end-products (AGEs); the main cause of pathogenesis and complications of many diseases. The presented study aimed to detect GA in healthy and cardiovascular patients' (CV) sera; however analysis of GA in biological fluid is a challenge and requires chemical derivatization. Hence, a new, highly sensitive, time saving and reproducible pre-column fluorescence derivatization procedure coupled with high performance liquid chromatography (HPLC) method was developed. The derivatization method was based on reaction of 2-aminobenzenthiol (2-ABT), a fluorogenic reagent, with GA in acidic medium to form highly fluorescent thiazine derivative (290 and 390 nm for excitation and emission wavelengths respectively). The fluorescent derivative was separated within 6 min on a reversed-phase ODS column using an isocratic elution with a mixture of methanol-water (70:30, v/v%). The proposed method parameters were optimized and the method was validated. A good linearity in the concentration range (0.05-5.0 µM) was obtained with detection limit (LOD) of 10 nM (200 fmol/injection), which is more sensitive than several previous methods. Moreover, the recovery results were within the range of 85.0-95.5 % and the intra- and inter-day precision results were ≤3.5%. It should be emphasized that this method is the first one for monitoring of GA in CV patients; to investigate its role for diagnosis and monitoring the severity and complications of this disease in clinical laboratory.

Highly sensitive cadmium sulphide quantum dots as a fluorescent probe for estimation of doripenem in real human plasma: application to pharmacokinetic study.

Thioglycolic acid-capped cadmium sulphide quantum dots (TGA-CdS QDs) have been synthesized and utilized as a fluorescent probe for the estimation of doripenem (DOR). Monitoring of DOR in different biological fluids is required to estimate the efficient dose to avoid bacterial infections and resistance. The investigated method is based on the measurement of fluorescence quenching of TGA-CdS QDs after the addition of DOR. The synthesized TGA-CdS QDs were characterized using transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, X-ray powder diffraction (XRD) and ZETA sizer. The TGA-CdS QDs showed unique photophysical properties with high quantum yield (0.32) using a comparison method with rhodamine B. Different experimental parameters affecting the synthesis process of the TGA-CdS QDs and their behavior with the studied drug DOR were examined and optimized. The values of the fluorescence quenching were linearly correlated to DOR concentration over the range of 10-500 ng mL-1 with a good correlation coefficient of 0.9991. The proposed method showed higher sensitivity over several reported methods, with LOD reaching 2.0 ng mL-1. The method was effectively applied for the estimation of DOR in human plasma and urine with good recovery results ranged from 95.16% to 99.51%. Furthermore, the stability of DOR in the human plasma was studied and a pharmacokinetic study of DOR in real human plasma was conducted.

Doppler ultrasonographic evaluation of brachial and femoral veins, and coagulation and lipid profiles in dogs following open splenectomy.

In dogs, splenectomy is mandatory as an emergency following splenic rupture with resultant hemoperitoneum and hypotensive shock. The present work aimed to evaluate the Doppler ultrasonographic parameters of brachial and femoral veins in splenectomized dogs and to investigate the effect of splenectomy on the coagulation and lipid profiles. A total number of 9 dogs underwent clinical, abdominal ultrasonographic and laboratory examinations prior to the surgical operation and kept for 60-day observation period post-splenectomy. Follow-up ultrasonography revealed no serious complications post-splenectomy. Both brachial and femoral veins were imaged medial to their corresponding arteries. Doppler ultrasonographic parameters of both veins showed no significant changes throughout the study period (P > 0.05). Haematological analysis revealed development of anemia, leukocytosis, and thrombocytosis in dogs post-splenectomy. Coagulation profile exhibited no significant variations in prothrombin and activated partial thromboplastin times (P > 0.05). In comparison with their baseline values, the mean concentrations of total cholesterol, low-density lipoprotein, and triglycerides were significantly increased 30-day post-splenectomy. In conclusion, it may seem that open splenectomy has no influence on the Doppler ultrasonographic indices of brachial and femoral veins with no evidence of deep vein thrombosis in dogs. However, persistent leukocytosis and thrombocytosis, as well as altered lipid profile may increase the risk of vascular complications with the long run. Therefore, a further long-term study may be required.