Sharif Digital Repository

A rapid, simple and efficient liquid chromatographic method was developed for simultaneous determination of three active ingredients namely, chlorpheniramine maleate, phenylephrine hydrochloride and guaifenesin along with sodium benzoate preservative common cold medications (syrups) and the method was validated based on the International Conference on Harmonization (ICH) and United State Pharmacopeia (USP) guidelines. Separation of the analytes was achieved within 15 min on a nucleosil gravity phenyl column in a single run with a mobile phase consisting of methanol: buffer mixture (15:85 v/v) at room temperature, in isocratic mode with flow rate of 0.8 mL min−1. A comprehensive study on... 

Degradation of Clindamycin phosphate (CMP) was studied in aqueous solutions by an anodic oxidation process under galvanostatic conditions. The electrolysis cell consisted of a Ti/SnO2-Sb anode, prepared by dip-coating technique, and a 316 stainless steel cathode, both of which had a surface area of 6 cm2. The effects of critical factors, including CMP concentration, current density, initial pH, and the supporting electrolyte were evaluated. The electrochemical oxidation of CMP was controlled by mass transport within the studied range. The kinetic analysis indicated that the degradation reactions followed pseudo-first-order equation. The rate of CMP decay, as well as that of COD removal,... 

Purpose: Different studies have analyzed the relationship between organizational learning (OL) and innovation performance (IP). However, the question of how innovation culture (IC) affects the relationship between OL and IP remains unexplored. This study aims to examine the impact of IC on the relationship between OL and various dimensions of IP, including product, process and objective innovation. Design/methodology/approach: A research model was developed and performed based on the relevant literature in the field of OL, IC and IP. The hypotheses are tested with the data collected from companies operating in an intensive knowledge-based industry. Findings: Based on the results of 625... 

The COVID-19 pandemic has been transformed into one of the main worldwide chal-lenges, in recent years. For controlling symptoms that are caused by this disease (e.g., chills or fever, shortness of breath and/or difficulty in breathing, cough, sore throat, fatigue, headache, muscle aches, the new loss of tastes and/or smells, congestion or runny nose, nausea, vomiting and/or diar-rhea), lots of medicines including analgesics, mucolytics, and anti-biotic/viral/inflammatory drugs have been frequently prescribed. As these medicines finally contaminate terrestrial and aquatic hab-itats by entering surface waterways through pharmaceutical production and excreting trace amounts of waste after... 

Pharmaceutical waste has attracted significant attention in the past two decades due to the current high consumption of pharmaceuticals together with the development of reliable detection technologies. In order to acquire better understanding on pharmaceuticals removal in biological processes, the treatment of synthetic wastewater containing diclofenac (DFN) and ibuprofen (IBU), two of the most commonly prescribed medicines worldwide, was studied using a moving bed biofilm reactor (MBBR). An 8.5-L aerobic MBBR with Kaldnes packing filling ratio of 40% was designed. The controlled parameters were pH within neutral range, temperature of 37 °C, mixed liquor suspended solids (MLSS) of 2100 mg/L,... 

The recently reported UNIversal QUAsiChemical Segment Activity coefficient (UNIQUAC-SAC) model [developed by Haghtalab and Yousefi Seyf Ind. Eng. Chem. Res. 2015, 54, 8611] provides a practical thermodynamic framework to be used in VLE, LLE, and SLE calculations. The UNIQUAC-SAC model has the advantage of being independent of area (q) and volume (r) structural parameters used in the combinatorial part. While the UNIFAC or UNIFAC-DMD could not apply to the 47% (44 of 94) of the studied molecules because of the undefined groups. Here, the numbers of solvents with identified segment numbers were extended from 82 to 130 with a slight refinement to the previous values. The model parameters... 

Suspension flow has an important role in various applications such as paint, material and pharmaceutical industries. Settling is considered as a resisting phenomenon in the processes dealing with suspensions. Using nanoparticles as an additive to micro-particulates has been studied in limited studies. This work presents an experimental investigation to assess the effectiveness of nanoparticles in reduction of suspension settling. Microscopic imaging and transmission measurement were used to analyze the stability factors in a container. Transmission analysis revealed that presence of nanoparticles in the suspension, decreased the sedimentation rate. Microscopy showed that the settling rate... 

Stock return is usually considered to be affected by firm's financial ratios as well as economic variables. Fundamental method assume that stock returns is not solely related to the stock market. Most result come from the company condition, industry situation and whole economy. In this paper, this relationship between stock return and fundamentals is studied using the data for 22 pharmaceutical companies in Tehran Stock Exchange over a 7 year period, and effective factors on stock return are investigated. Because of our data natural we used panel data model from econometric methods. The results show that 80 pecent of change in stock return can be explained with 9 fundamental variables... 

The voltammetric performance of edge-plane pyrolytic graphite (EPG) electrode via adsorptive stripping voltammetry was investigated for study of the electrochemical behavior of omeprazole (OMZ) in aqueous solution. The results revealed that the oxidation of OMZ is an irreversible pH-dependent process that proceeds with the transfer of one electron and one proton in an adsorption-controlled mechanism. The determination conditions, such as the pH values of the supporting electrolyte, accumulation time and scan rate were optimized. Simplicity, high reproducibility and low detection limit (3 nM) of the electrode response as well as wide linear range (0.01 to 4.0 µM) can be stated as significant... 

New achievements in the realm of nanoscience and innovative techniques of nanomedicine have moved micro/nanoparticles (MNPs) to the point of becoming actually useful for practical applications in the near future. Various differences between the extracellular and intracellular environments of cancerous and normal cells and the particular characteristics of tumors such as physicochemical properties, neovasculature, elasticity, surface electrical charge, and pH have motivated the design and fabrication of inventive "smart" MNPs for stimulus-responsive controlled drug release. These novel MNPs can be tailored to be responsive to pH variations, redox potential, enzymatic activation, thermal... 

Chiral discrimination has always been a hot topic in chemical, food and pharmaceutical industries, especially when dealing with chiral drugs. Enantiomeric recognition not only leads to better understanding of the mechanism of molecular recognition in biological systems, but may further assist in developing useful molecular devices in biochemical and pharmaceutical studies. By emerging nanotechnology and exploiting nanomaterials in sensing applications, a great deal of attention has been given to the design of optical nanoprobes that are able to discriminate enantiomers of chiral analytes. This review explains how engineering nanoparticles (NPs) with desired physicochemical properties allows... 

in this paper we present an integrated classifier that is used in mammogram MR-image for classification of breast cancers and abnormalities using a Multi-stage classifier, the method developed here first classifies mammograms into normal and abnormal and then for abnormal cases determines that if the case cancer is benign or malignant and also determine the type of breast cancer. In this paper there are two main topics that must be considered. First one is selection of good features and second is designing a good structure for classifier. In this study, the features are a combination of some features that are extracted from Spatial Grey Level Dependency matrix and some statistical descriptor... 

Since the beginning of the COVID-19 pandemic, nearly most confirmed cases develop respiratory syndromes. Using targeted drug delivery by microcarriers is one of the most important noteworthy methods for delivering drugs to the involved bronchi. This study aims to investigate the performance of a drug delivery that applies microcarriers to each branch of the lung under the influence of a magnetic field. The results show that by changing the inlet velocity from constant to pulsatile, the drug delivery performance to the lungs increases by ∼31%. For transferring the microcarriers to the right side branches (LUL and LLL), placing the magnet at zero height and ∼30° angle yields the best outcome.... 

Penicillin G is an active pharmaceutical ingredient of great importance in health sectors. Meanwhile, because of its huge quantity production and resistance to biodegradability, this antibiotic is ubiquitously presented in aquatic environment. In this study, the degradation of effluent wastewater from Penicillin G production plant by Photo- Fenton process and Ultrasound process (Sonolysis) was investigated, the effects of different process variables in both methods were evaluated and at last the degradation of Pen-G by these two processes in the optimum conditions was compared. Pen-G concentration and Chemical Oxygen Demand (COD) were selected as the environmental parameters to follow the... 

A sensitive colorimetric method for the detection of ascorbic acid was proposed in this research based on the reduction of silver ions by ascorbic acid in the presence of citrate-stabilized silver seeds, additional trisodium citrate and a polymer such as polyvinylpyrrolidone. The color of the stable sol is controlled by varying the concentration of trisodium citrate (TSC), polyvinylpyrrolidone, silver nitrate and silver seeds. The reduction of Ag + to triangle silver nanoparticles (Ag-NPs) by ascorbic acid in the presence of trisodium citrate (TSC) and silver seeds produced two very intense surface plasmon resonance peaks of Ag-NPs. The plasmon absorbance of Ag-NPs allows the quantitative... 

Blend drug-loading method in electrospun scaffolds has gained much attention as a cost-effective and simple delivery system in regenerative medicine. However, it has some drawbacks, such as the burst release of encapsulated drugs and denaturing active agents in harsh organic solvents. In this study, a new silk fibroin-gelatin (SF–G) fibrous sheet has been introduced as an engineered scaffold and a straightforward drug delivery system for skin tissue engineering applications. The hybrid sheets have been prepared via co-electrospinning and in-situ crosslinking methods without corrosive solvents and toxic crosslinking agents. To evaluate the proposed scaffold as a controlled release system, the... 

Development of simple yet precise sensing platforms for rapid determination of biological species and drugs is of paramount importance, not only for analysis of pharmaceutical formulations during the production stage, but also in clinical practices and medical diagnosis. In the present research, we report on the electrochemical determination of atorvastatin (ATOR) by using silver nanowires/gold-modified glassy carbon electrode (Ag NWs/Au/GCE). The modified electrode was constructed through a two-step procedure in which narrow silver nanowires synthesized via a polyol method are drop casted on a pre-modified GCE with electrodeposited gold particles. The results of XRD analysis indicated the...