Browsing by Author "El-Naem, Omnia A"

Now showing 1 - 6 of 6

Appraisal for Edible Use of Vegetable Crops Cultivated in Egypt after 2 Treatment with Selected Insecticides and Fungicides: Insights of Dissipation 3 Rates and Pre-Harvest intervals
(J-Stage, 7/16/2021) Saleh, Sarah S; Monir, Hany H; El-Naem, Omnia A
An analytical investigation was carried out to study the dissipation rate of two commonly used pesticides, Thiamethoxam (neonicotinoid insecticide) and propamocarb hydrochloride (carbamate fungicide) applied to four vegetable crops: cucumber, zucchini, lettuce and pepper, after open- field application. Samples were harvested according to a scheduled plan followed by QuEChERS extraction, then thiamethoxam residues were analyzed using a GC-ECD method, while propamocarb HCl residues were analyzed using an HPLC-UV method. Validation parameters were attained for both methods and the kinetic profile was studied which fitted the first –order kinetics where k, t ½ and t90 were calculated. The proper pre-harvest interval (PHI) was studied for each crop to ensure that the residues levels declined to reach below the maximum residue limit (MRL) where the crop is suitable for edible use. These values were found to be different from labelled values which proves that the PHIs are greatly affected by changing weather conditions.
Eco-friendly UPLC-MS/MS Analysis of Possible Add-On Therapy for COVID-19 In Human Plasma: Insights of Greenness Assessment
(Elsevier, 04/02/2021) El-Naem, Omnia A; Saleh, Sarah S
Facing the pandemic COVID-19 is of highest priority for all researchers nowadays. Recent statistics indicate that the majority of the cases are home-treated. Two drugs of interest, Guaifenesin and Bromohexine HCl, are among the add-on therapy for treatment of COVID-19 mild cases, which has raised the need for their simultaneous determination. The analysis of the two drugs of interest was described using ultra-performance liquid chromatography–tandem mass spectrometric (UPLC–MS/MS) in plasma of healthy human volunteers using tetryzoline HCl as an internal standard (IS) after liquid-liquid extraction. The applied chromatographic conditions were Kinetex C18 (100Å, 2.6 µm X 50 mm X 4.6 mm) column and a mixture of methanol: water (95: 5, v/v) as a mobile phase at flow rate 1 mL/min. The positive ionization mode was used for detecting the ions, by observing the pairs of transition m/z 199< 125 for GUF, m/z 377< 114 for BRM and m/z 201 <131 for IS. The linearity range was from 50-1500 ng/mL for GUF and 0.5-50 µg/mL for BRM. Limit of detection (LOD) was found to be 35.16 and 0.43 ng/ml for GUF and BRM, respectively. The method was validated according to FDA guidance. The proposed method was assessed to be more eco-friendly versus the reported method using the greenness assessment tools: National Environmental Methods Index (NEMI), Assessment of Green Profile (AGP), Green Analytical Procedure Index (GAPI) and Eco-Scale. The proposed method was applied for the application of a pilot pharmacokinetic study.
The power of High Impact Amplitude Manipulation (HIAM) technique for extracting the basic spectra of two Fixed-dose combinations (FDC) -Spectrophotometric purity analysis via spectral contrast angle
(Elsevier, 15/02/2022) Saleh, Sarah S; Lotfy, Hayam M; Tiris, Gizem; Erk, Nevin; El-Naem, Omnia A
HIAM technique allows the extraction of the original constant signal of each single component out of interference signals of a mixture and further transformed into basic spectrum (D0 ). It includes the meth- ods: ratio subtraction coupled with unified constant subtraction (RS-UCS), constant center (CC) and con- stant extraction (CE). The technique was introduced for the analysis of two pharmaceutical formulations used to treat cardiovascular diseases. The formulations are binary combinations of Amlodipine (AML) with either Atorvastatin (ATR) or Candesartan (CND) which shows interefernce absorbance signals. The technique was valid over the linearity range of (5.0–35.0 mg/ml) for AML, ATR and CND with recovery per- centage 100.40 ± 1.88 , 100.00 ± 0.86 and 99.83 ± 1.07, respectively . The extracted signals were tested for its purity by spectral contrast angle (cos h) to illustrate the efficency of the HIAM technique where cos h values ranges from (0.9902 to 0.9986). The presented technique was fully validated regarding ICH guide- lines and were statistically compared using one-way ANOVA at 95% confidence.
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy Volume 273, 15 May 2022, 121036 The power of High Impact Amplitude Manipulation (HIAM) technique for extracting the basic spectra of two Fixed-dose combinations (FDC) -Spectrophotometric purity analysis via spectral contrast angle
(Elsevier, 01/05/2022) Saleh, Sarah S; Lotfy, Hayam M; Tiris, Gizem; Erk, Nevin; El-Naem, Omnia A
HIAM technique allows the extraction of the original constant signal of each single component out of interference signals of a mixture and further transformed into basic spectrum (D0). It includes the methods: ratio subtraction coupled with unified constant subtraction (RS-UCS), constant center (CC) and constant extraction (CE). The technique was introduced for the analysis of two pharmaceutical formulations used to treat cardiovascular diseases. The formulations are binary combinations of Amlodipine (AML) with either Atorvastatin (ATR) or Candesartan (CND) which shows interefernce absorbance signals. The technique was valid over the linearity range of (5.0–35.0 µg/ml) for AML, ATR and CND with recovery percentage 100.40 ± 1.88 , 100.00 ± 0.86 and 99.83 ± 1.07, respectively . The extracted signals were tested for its purity by spectral contrast angle (cos θ) to illustrate the efficency of the HIAM technique where cos θ values ranges from (0.9902 to 0.9986). The presented technique was fully validated regarding ICH guidelines and were statistically compared using one-way ANOVA at 95% confidence
A validated liquid chromatography-tandem mass spectrometric method for the determination of co- administered ranitidine and metronidazole in plasma of human volunteers
(Royal Society of Chemistry, 2021-05) El-Naem, Omnia A; El-Maraghy, Christine M
This work describes the development, optimization and validation of a liquid chromatography-tandem mass spectrometric method (LC-MS/MS) for the simultaneous analysis of co-administered ranitidine (RAN) and metronidazole (MET) in plasma of healthy human volunteers. A simple protein precipitation procedure using 1 mL acetonitrile was applied to extract both drugs and metoclopramide as an internal standard (IS) from plasma. The chromatographic separation was achieved on a C18 column with isocratic elution of the mobile phase consisting of acetonitrile and 0.1% formic acid (90 : 10, v/v) at a flow rate of 0.35 mL min−1. The positive ionization mode was used for detecting the ions, by observing the pairs of transition m/z 314.82 < 176.06 for RAN, m/z 172.03 < 127.95 for MET and m/z 299.86 < 277.10 for IS. The linearity range was from 5–600 ng mL−1 for RAN and 2–40 μg mL−1 for MET. The method was found to be sensitive and accurate with good simple extraction recovery and matrix effect, according to FDA guidelines for bioanalytical methods. The developed method could be applied for further bioavailability studies that could be useful in therapeutic drug monitoring
A validated liquid chromatography-tandem mass spectrometric method for the determination of co-administered ranitidine and metronidazole in plasma of human volunteers†
(Royal Society of Chemistry, 6/21/2021) El-Naem, Omnia A; El-Maraghy, Christine M
This work describes the development, optimization and validation of a liquid chromatography-tandem mass spectrometric method (LC-MS/MS) for the simultaneous analysis of co-administered ranitidine (RAN) and metronidazole (MET) in plasma of healthy human volunteers. A simple protein precipitation procedure using 1 mL acetonitrile was applied to extract both drugs and metoclopramide as an internal standard (IS) from plasma. The chromatographic separation was achieved on a C18 column with isocratic elution of the mobile phase consisting of acetonitrile and 0.1% formic acid (90 : 10, v/v) at a flow rate of 0.35 mL min−1. The positive ionization mode was used for detecting the ions, by observing the pairs of transition m/z 314.82 < 176.06 for RAN, m/z 172.03 < 127.95 for MET and m/z 299.86 < 277.10 for IS. The linearity range was from 5–600 ng mL−1 for RAN and 2–40 μg mL−1 for MET. The method was found to be sensitive and accurate with good simple extraction recovery and matrix effect, according to FDA guidelines for bioanalytical methods. The developed method could be applied for further bioavailability studies that could be useful in therapeutic drug monitoring.