
Aya M. Mostafa- Doctor of Philosophy
- Lecturer at Assiut University
Aya M. Mostafa
- Doctor of Philosophy
- Lecturer at Assiut University
Lecturer at the Faculty of Pharmacy, Assiut University, Egypt
About
29
Publications
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Introduction
I am a lecturer of Pharmaceutical Analytical Chemistry at Faculty of Pharmacy - Assiut university - Egypt.
My research interests include Analytical separations, Bioassays, Molecularly imprinted polymers, Biosensors, Optical sensors, and Environmental analysis.
I have received the Newton Mosharafa Scholarship to carry out my PhD at Kingston University, London, UK.
Skills and Expertise
Current institution
Additional affiliations
January 2019 - present
Assiut university faculty of pharmacy
Position
- Assistant lecturer
Publications
Publications (29)
A novel, highly sensitive fluorometric method for D-penicillamine (D-PA) detection has been developed, addressing critical needs in therapeutic drug monitoring. D-PA, a crucial chelating agent used in treating Wilson’s disease, rheumatoid arthritis, and heavy metal poisoning, requires precise quantification due to its narrow therapeutic window and...
Glutathione (GSH) plays essential roles in anti-oxidation and detoxification within the human body. An imbalance in its concentration can lead to serious health conditions. Therefore, accurate monitoring of GSH is critical for maintaining human health. In this study, we present a novel GSH detection method that enhances the fluorescence of α-lipoic...
This study pioneers a sustainable strategy for synthesizing yellow-emissive carbon dots (Y-CDs) using expired rabeprazole sodium tablets, thereby transforming pharmaceutical waste into valuable nanomaterials.
A novel ratiometric fluorometric method has been developed for the determination of metformin (MET) using a dual-emission system composed of copper ion-modified nitrogen-doped carbon dots (Cu2+/NCDs) and eosin. The sensing mechanism exploits MET’s inherent properties, specifically its strong positive charge and high complexation affinity due to ami...
This study presents a novel and sensitive method for the determination of glutathione (GSH), a crucial antioxidant and cellular protectant, using dual blue/orange-emitting carbon dots (BO-CDs) and phenolphthalein (PHP). The sensing system operates at pH 9.0, exploiting the unique optical properties of BO-CDs with emission peaks at 420 nm and 570 nm...
This study presents a novel dual-modal approach for glutathione (GSH) detection using blue and yellow dual-emission carbon dots (BY-CDs) and bromothymol blue (BTB) at pH 8.0. The method employs both colorimetric and fluorometric detection modes, offering a new perspective on GSH quantification. BTB's blue coloration induces selective fluorescence q...
A novel fluorometric method for the determination of L-asparaginase, an enzyme crucial in cancer therapy and food industry applications, is presented. This sensitive and selective approach utilizes L-asparagine and two pH-sensitive carbon dots (blue-N-CDs and red-N-CDs) as probes. The interaction between L-asparagine and L-asparaginase liberates am...
This study presents a novel and selective method for the determination of l-asparagine in diverse potato varieties under various storage conditions. L-asparagine levels serve as a crucial indicator for acrylamide formation, a hazardous substance in processed potato products. The fluorometric method utilized blue-emitting CDs (B-CDs), orange-emittin...
Design and preparation of a fluorescent molecularly imprinted membrane for the selective detection of pepsin enzyme as a biomarker for gastroesophageal reflux disease, Talanta Open (2024), doi: https://doi. 1 HIGHLIGHT • A novel fluorescent molecularly imprinted membrane was developed for pepsin. • Hydrophilic monomers and crosslinkers were employe...
A novel and sensitive fluorescence ratiometric method is developed for urea detection based on the pH-sensitive response of two fluorescent carbon dot (CD) systems: R-CDs/methyl red (MR) and NIR-CDs/Cu²⁺. The sensing mechanism involves breaking down urea using the enzyme urease, releasing ammonia and increasing pH. At higher pH, the fluorescence of...
This study develops a novel fluorometric method for the sensitive and selective determination of urea, based on unique system comprising nitrogen doped red-emissive carbon dots (NRECDs), zinc-dithizone complex, and the urease enzyme. The underlying principle of this method relies on the pH increase resulting from the enzymatic breakdown of urea by...
The monitoring of ziram levels is of vital importance due to its widespread application in agriculture and the possible risks it poses to human health and the ecosystem. This work proposes an innovative approach for the highly sensitive and selective sensing of ziram, a widely used dithiocarbamate fungicide, through the formation of copper dimethyl...
Glutathione (GSH) is an important antioxidant biomarker with pivotal roles in multiple biological processes. Herein, a novel dual-emission ratiometric fluorescence nanoprobe was developed for selective and sensitive GSH detection by exploiting competitive interactions with a silver-riboflavin (Ag-RF) complex. The nanoprobe consists simply of a mixe...
Two fluorescent molecularly imprinted polymers (MIPs) were developed for pepsin enzyme utilising fluorescein and rhodamine b. The main difference between both dyes is the presence of two (diethylamino) groups in the structure of rhodamine b. Consequently, we wanted to investigate the effect of these functional groups on the selectivity and sensitiv...
This work presents a simple yet selective fluorometric protocol for the quantification of vancomycin, an important antibiotic for treating infections caused by Gram-positive bacteria. A novel ratiometric fluorometric method for the determination of vancomycin is developed based on dual emissive carbon dots (DECDs) with emission at 382 nm and 570 nm...
Cisplatin (CIS) and etoposide (ETP) combination therapy is highly effective for treating various cancers. However, the potential for pharmacokinetic interactions between these drugs necessitates selective sensing methods to quantitate both CIS and ETP levels in patient's plasma. This work develops a dual fluorescence probe strategy using glutathion...
This work pioneers a selective fluorometric assay for the fibrinolytic agent streptokinase by strategically coupling its thrombolytic action to fluorescence signaling using carbon dots integrated into fibrin clot network. Streptokinase triggers clot lysis and caused release of photoluminescent carbon dots integrated within the fibrin network in a c...
A novel selective and reliable ratiometric fluorescence probe has been successfully synthesized for precise, sensitive, and simple quantitation of methotrexate (MTX). Hydrothermal method was employed to fabricate nitrogen-doped carbon dots using Annona squamosa seeds (AS-CDs) as a starting material, and their characteristics were confirmed using tr...
This study focuses on the interaction between the antihyperlipidemic drug fluvastatin (FLV) and the antidiabetic drug empagliflozin (EMP), which are commonly co-administered medications. EMP's impact on FLV levels is attributed to its inhibition of organic anion transporting polypeptide 1B1 (OATP1B1), responsible for FLV liver uptake, consequently...
This research work introduces a novel sensor that utilizes two fluorophores to enable simultaneous monitoring of gentamicin sulphate (GNT) and ketorolac tromethamine (KET). The innovative sensor is composed of carbon dots (CDs) derived from black grapes (BG) and eosin Y (EY) dye. The interaction between the studied drugs and EY/BG@CDs sensor compon...
This study focuses on the determination of the active metabolite of molnupiravir (MOL), N-hydroxycytidine (NHC), using a square wave voltammetric (SWV) method. Carboxylesterase-2 enzymes catalyze the conversion of MOL prodrug into NHC. However, co-administration of verapamil (VER), a carboxylesterase-2 inhibitor, may reduce the levels of NHC, leadi...
Salivary pepsin is a very important and selective biomarker for gastroesophageal reflux disease and high concentrations in the saliva of potential patients can provide a very useful and non-invasive diagnostic tool. Therefore, this study focused on the development of new and highly selective magnetic molecularly imprinted polymers (MIPs) for the ex...
Molecularly imprinted polymers (MIPs) are a type of artificial polymer, which have complementary cavities that are designed to bind a specific target molecule with a high degree of selectivity. Due to their effectiveness and stability, MIPs have found their way into many applications in medicine, chemistry, analysis and sensing fields. One of the m...
A simple and highly sensitive Ultra High‐performance Liquid Chromatographic ‐Diode array detection method (UHPLC‐DAD) was developed and validated for the simultaneous estimation of levetiracetam (LEV) and lacosamide (LAC). It was clinically proven that the combination of LEV and LAC exhibits a synergistic effect against refractory seizures in mice,...
A simple and sensitive high performance thin-layer chromatographic method (HPTLC) was developed and validated for the analysis of two binary mixtures of antiepileptic drugs. The first mixture consists of eslicarbazepine acetate (ESL) and oxcarbazepine (OXC). The second one consists of carbamazepine (CBZ) and OXC. These drugs have intercalated metab...
Two new, simple, selective, and highly sensitive spectrofluorimetric methods were developed and validated for determination of the antiepileptic drug; retigabine (RTG). The first method (Method-I) depends on enhancement of the weak native fluorescence of RTG via the use of an organized medium; sodium dodecyl sulphate (SDS) in acetate buffer (pH 3.7...
In the last few decades, many new antiepileptic drugs came out to medicine world, and their use was expanded over a wide range of cases. Analysts from all over the world developed many different separation methods for the determination of these drugs in a quantitative way either in pharmaceutical dosage forms or in biological fluids. In this review...
Questions
Questions (8)
Hello
I am trying to digest a protein using endoproteinase aspN enzyme. However, I can't find any suitable procedure in literature. If anyone used this enzyme before, I can really use the help.
During the development of molecularly imprinted polymers (MIPs) and non-imprinted polymers (NIPs), I many times find that the binding of NIPs to the target is better than MIPs which doesn't make sense since MIPs are the ones developed in the presence of the target.
The binding assay i use is incubating exact mass of both polymers with exact volume of specific concentration of target for 2 hours then centrifuging and measuring absorbance of supernatant to determine the amount of free target.
This problem has been reoccurring a lot, does anyone have a reasonable explanation?
Hello
I am preparing fluorescent MIPs however how do i measure their fluorescence on a spectrofluorimetre while they are suspended in the solution as solid. As far as i know all fluorescence measurements have to be carried out using a clear solution or the particles would impede the light from the excitation source.
Anyone has an idea how that works?
I am working on magnetic MIPs, however i have no practical experience in the field, if someone did work on them before, i need to ask some questions please.
Thank you
I am preparing molecularly imprinted polymers on protein templates and i need to ask few questions if anyone has enough experience please get in touch.
I am separating mixture of two very closely related compounds on TLC the best system produced 0.08 difference in the Rf values of the two compounds .... can this difference be acceptable ... i tried millions of systems before, that's the best i could produce ....
one compound is ester and other is ketonic >> any suggestions on mobile phase ?
i need to perform CUAAC on a drug containing an alkyne group and i don't have any THPTA ligand , can i use any other one ?