Tablet Samples Research Articles

Multi-core–shell nanoboxes comprising polydopamine-derived C coated NiCo@C and FeCo@C nanohybrid for enhanced electrochemical quantification of nitrofurantoin

The development of a high-performance electrochemical sensing platform for monitoring nitrofurantoin (NFT) levels in various real samples plays an important role in the research community worldwide. To accomplish this objective, the crucial challenge is to construct sensing interfaces with outstanding electrocatalytic capabilities. In the present work, a highly efficient metal@carbon electrocatalyst with porous and multi-core–shell nanobox structure comprising polydopamine (PDA)-derived C coated NiCo@C and FeCo@C nanohybrid (named as NiCo@C/FeCo@C@C) was fabricated by simply pyrolyzing NiCo@FeCo Prussian blue analogues (PBA)@PDA. The carbonization of PDA into carbon shells protected the framework from collapsing during high-temperature pyrolysis process, thus enlarging the specific surface areas and porosity. The NiCo@C/FeCo@C@C composite attained an enhanced electrochemical capability, such as an outstanding electronic conductivity from the double carbon shell with porous structure, a large number of active sites and a high electrocatalytic activity from the metallic alloy nanoparticles, which exhibited a highly sensitive response to NFT. Under optimized experimental conditions, the established NiCo@C/FeCo@C@C electrochemical sensor displayed a wide linear range of 0.05–100 μM for NFT determination, coupled with a low detection limit of 14 nM. The practical feasibility of this sensor was also confirmed by the analysis of NFT in tablet and lake water samples with outstanding recovery rates. Moreover, the sustainability of the sensor was demonstrated through its prominent performance in high reproducibility, selectivity and long-term stability. This study thus introduces an innovative approach for the advance of highly efficient electrocatalysts in the area of electrochemical sensing.

Fluorescent and colorimetric dual-mode recognition of Al3+ in tablets based on chrome azurol S and pH-switchable boron, nitrogen co-doped carbon dots.

The synthesis and characterization ofpH-sensitive boron and nitrogen co-doped CDs (B, N-CDs) is reported. The fluorescence of B, N-CDs exhibited pH-responsive behavior within the range pH3.0-6.0, attributed to their controlled aggregation and disaggregation. Interestingly, the fluorescence of B, N-CDs was quenched by the inner filter effect from chrome azurol S (CAS). With the subsequent addition of Al3+, the fluorescence of B, N-CDs was restored due to the formation of blue Al3+-CAS and B, N-CDs-Al3+ complexes. Consequently, a fluorescent and colorimetric dual-mode sensor for Al3+ detection was developed. The proposed sensor enabled Al3+ detection in the ranges and limits of detection of 3.75-22.5μM and 2.67μM for the fluorescent mode and 5-20μM and 4.8μM for the colorimetric mode, respectively. Furthermore, the efficacy of the sensor was validated through successful detection of Al3+ in tablet samples. The obtained B, N-CDs promised the application in acid condition and the proposed sensor isexpected tobe applied toin situ on-line detection of Al3+.

Assessment of miligram(Mg) content of some notable analgesics used by residents of Maiduguri Metropolis: evidence from high performance liquid chromatographic technique

Diclofenac sodium and paracetamol are Over the counter (OTC) medications used as analgesic and antipyretic agents to relieve pains, fever and headaches. The aim of this work was determine the mg content of paracetamol and diclofenac sodium in selected samples across the Maiduguri metropolis using High Performance liquid chromatography (HPLC) method. For paracetamol samples an intersil ODS-3V column (150 mm × 4.6 mm; 5 μm pore size) was used at the temperature of 35oC the mobile phase was methanol: water (20:80) using isocratic elution at the flow rate of 2 mL/min, injection volume of 10 μL and a diode array detector. For diclofenac sodium samples, the chromatographic conditions were the same except the mobile phase which was methanol: water (63:37), flow rate of 0.8 mL min, injection volume of 20 μL and column temperature was set at 30 oC. A total of 45 samples were analysed; which comprised of paracetamol tablet, paracetamol syrup and diclofenac sodium tablet which were randomly selected from three different sources; hospital pharmacy, community pharmacy and drug patent stores. The percentage mg content for paracetamol tablets ranged from 48 to 83 % while that of the paracetamol syrups ranged from 72 to 120 % and finally diclofenac sodium tablets ranged from 73 to 174 %. Adopting the United State Pharmacopoeia (USP) as reference for assessment tool, it was observed that all the paracetamol tablet samples failed, 4 out of 15 paracetamol syrup samples failed, and 11 out of 15 diclofenac sodium tablet samples failed. There was statistical significance (p< 0.05) between class of drug and percentage mg content but there was no significance (p< 0.05) between source of drug and percentage constituent. HPLC technique was used successfully for quantitative determination of paracetamol and diclofenac sodium dosage forms.

Green synthesis of self-oriented flower-like Ag@Ag2O nanostructures functionalized with L-Tryptophan for colorimetric simultaneous determination of ultra-trace level of thiamin and riboflavin

The study focuses on the green synthesis of Ag@Ag2O nanostructures using Padina algae extract and functionalizing them with L-tryptophan to enhance their properties as a colorimetric sensor for simultaneous detection of ultra-trace levels of thiamin and riboflavin. The nanostructures are characterized using techniques like XRD, FESEM, FTIR, TEM, AFM, and DLS to understand their morphology, structure, and interactions with target molecules. FESEM analysis revealed the hierarchical flower-like Ag@Ag2O nanostructures. The TEM image shows the formation of core-shell nanostructures. Also, DLS analysis and surface zeta potential spectra illustrated the aggregated nature of fabricated nanocomposites in the presence of vitamins. The study is the first to report simultaneous determination of thiamin and riboflavin using a colorimetric sensor based on Ag@Ag2O-L-Try nanocomposites using partial leas square (PLS). The dynamic range of thiamin and riboflavin was achieved in 0.1 mol L−1 acetate buffer pH 4 and the ratio Ag@Ag2O: L-try 1:1. The Ag@Ag2O-L-Try sensor exhibited two linear ranges of 0.1- 1.0 and 3-350 µMol L− 1 for riboflavin and a linear range 3.0–60 µMol L− 1 for thiamin. Also, low detection limit of 1.92 µMol L− 1 and 0.048 µMol L− 1 was obtained for riboflavin and thiamin, respectively. The results indicated that the success of the method depends on the selective and sensitive colorimetric assay of the sensor along with the simultaneous determination by the PLS algorithm. Hence, the proposed technique can be used for the accurate and precise determination of vitamins in different pharmaceutical syrup and tablet samples.

Electrochemical Oxidation of Glutathione in the Presence of Tryptophan at Carbon Paste Electrode Modified with Ni-Zn-Metal-Organic Frameworks/Graphene Oxide and Ferrocene Derivative

Glutathione (GSH) plays a vital physiological role as it is implicated in the progression and pathogenesis of a wide range of medical conditions, including diabetes, various types of cancer, and Parkinson’s disease. Due to the fundamental physiological importance of GSHand its relevance to numerous medical conditions, there is a clear need to develop simple, rapid, and cost-effective analytical methods. These methods could significantly aid in clinical diagnostics and guide the optimization of treatment approaches. This work reports the synthesis and characterization of a Ni-Zn-metal-organic framework/graphene oxide (Ni-Zn-MOF/GO) composite material, and its application as a modifier for a carbon paste electrode (CPE) in the electrochemical detection of GSH. The Ni-Zn-MOF/GO/ferrocene (FC)-modified CPE (Ni-Zn-MOF/GO/FC/CPE) was developed for this purpose. The Ni-Zn-MOF/GO/FC/CPE electrochemical sensor exhibited two linear response ranges for GSH: from 0.01–90.0 μM, and from 90.0–800.0 μM, with a detection limit estimated to be 0.003 μM. Importantly, Ni-Zn-MOF/GO/FC/CPE was shown to be suitable for the determination of GSH in the presence of tryptophan in real samples, such as human blood, GSH tablet and urine samples. The results highlight the potential of the Ni-Zn-MOF/GO/FC/CPE electrochemical sensor as a reliable and sensitive platform for the detection of GSH.

A highly sensitive and selective molecularly imprinted sensor for the determination of atorvastatin

In this study, we developed a highly sensitive carbon paste sensor that combines a molecularly imprinted polymer (MIP) with specific recognition capabilities to monitor atorvastatin (ATV). In the MIP synthesis, designed especially for ATV, ethylene glycol dimethacrylate (EGDMA) was utilized as a cross-linking monomer and methacrylic acid (MAA) as a functional monomer. This non-covalent method made use of polymerization by free radicals. After that, this MIP was added to a carbon paste electrode (CPE), which served as both a selective detection element and a preconcentration agent for ATV analysis. The improved CPE was characterized using scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). To investigate ATV, the anodic peak signal was assessed using square wave stripping voltammetry (SWSV).The calibration curve exhibited two linear regions encompassing dosages from 0.005 to 1 µM and 1 to 20 µM, with a 1.5 nM calculated detection limit. The designed MIP electrode was successfully utilized to assess ATV in tablet and human blood serum samples, demonstrating its usefulness in practical analysis.

Porous mesh poly-L-Cysteine and lamellar polynicotinamide-based electrochemical sensor for melatonin detection in milk and tablets

An poly L-Cys/NADH/GCE electrochemical sensor for melatonin (MT) detection was developed by electropolymerising reticulated poly L-cysteine (poly L-Cys) and lamellar poly-nicotinamide adenine dinucleotide (NADH) on a glassy carbon electrode (GCE). The morphology, elemental composition, and elemental states of the fabricated electrochemical sensor were characterized through scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). Additionally, the electrochemical behavior of melatonin on poly L-Cys/NADH/GCE was investigated through electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and differential pulse voltammetry (DPV). The results showed a linear relationship for MT across the concentration range of 0.1 to 1000.0 µmol/L, with linear equations Ip(µA) = 0.0978c(µmol/L) + 0.0981, R2 = 0.9937 (concentration range: 0.1–40.0 µmol/L), and Ip(µA) = 0.0137c(µmol/L) + 5.2741, R2 = 0.9636 (concentration range: 40.0–1000.0 µmol/L). The recoveries in milk samples ranged from 98.71 % to 107.98 %, with relative standard deviations (RSD) for actual tablet samples below 8.60 %. Furthermore, the electro-oxidation sites of MT and its reaction process were deduced by calculating electron orbitals and electron cloud diagrams.

Large Dynamic Range Spectral Measurement in Terahertz Region Based on Frequency Up-Conversion Detection via OH1 Crystal.

Terahertz spectroscopy systems, which integrate terahertz sources and detectors, have important applications in many fields such as materials science and security checking. Based on highly sensitive frequency up-conversion detection, large dynamic range spectral measurements in a terahertz region are reported. Our system realized the detection sensitivity at a 10 aJ level with a 2-(3-(4-hydroxystyryl)-5,5-dime-thylcyclohex-2-enylidene) malononitrile (OH1) crystal and a dynamic range up to seven orders. Based on this system, we verified the validity of the spectral measurement with tests which were conducted on monohydrate glucose, anhydrous glucose and mixed tablet samples with a thickness of 0.8 mm in 1~3 THz, respectively. Also, a mini coppery elbow tube with an inner diameter of 1 mm was used for the transmission of a terahertz wave to simulate some strip biological tissue samples. By allowing terahertz to transmit through this tube filled with 0.5 g glucose powder, we successfully obtained the absorption spectrum with a minimum transmittance at the absorption peak in the order of 10-4.

Enhanced electrocatalytic activity of hafnium doped tungsten oxide (Hf-WO3) for ultrasensitive detection of nonsteroidal anti-inflammatory drug

Efficient hafnium-doped tungsten oxide nanoparticles (Hf-WO3) were developed by hydrothermal approach and characterization was carried out by X-ray diffraction pattern (XRD), transmission electron microscopy (TEM), high resolution-transmission electron microscopy (HR-TEM), scanning transmission electron microscopy (STEM), X-ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy (EIS) techniques. Cyclic voltammetry (CV) and square wave voltammetry (SWV) techniques were employed to assess the electrochemical response of the fabricated carbon paste electrodes (CPE) for the analysis of mefenamic acid (MA). The objective of this work is to develop and optimize parameters to enhance the selectivity and sensitivity of Hf-WO3 modified sensor for the trace-level detection of MA, addressing its critical importance in both pharmaceutical and environmental analysis. The Hf-WO3 predominantly showed a monoclinic phase with some hexagonal peaks, confirming its good crystallinity and 1-D structure, which enhances charge transport and catalytic sites. XPS analysis confirmed the formation of pure Hf-WO3 by showing distinct W and Hf peaks and verifying their valences: W in the +6 state and Hf in the +4 state. CV showed that the Hf-WO3/CPE greatly enhances the electrochemical oxidation of MA compared to unmodified and tungsten oxide-modified electrodes, with a six-fold increase in peak current and notable redox activity attributed to improved surface properties and charge transfer efficiency. Under optimum experimental conditions, the Hf-WO3/CPE exhibits a low limit of detection (LOD) of 3.94 nM with dynamic concentration linearity ranging from 0.01 to 100.0 μM with good sensitivity of 1.74 μAμM−1cm−2. Furthermore, the Hf-WO3/CPE was employed in real-time analysis of MA in spiked urine samples and pharmaceutical tablet samples, which showed satisfactory recovery results ⁓ 98 %. Moreover, the electrode showed good stability over multiple measurements, and these results demonstrate that Hf-WO3/CPE is a promising sensor for MA detection.

Thermophysical properties of manganese ferrite nanoparticles and manganese ferrite samples irradiated with γ-rays

In this article, thermophysical properties of manganese ferrite nanoparticles and 4×15×5 mm manganese ferrite samples in the tablet form prepared of these nanoparticles were investigated. The tablet samples were irradiated with γ-rays for 1 and 5 hours. After irradiation, physical characteristics of the heat flux of these samples were measured using a differential scanning calorimeter. Differential scanning calorimeter spectrum of the manganese ferrite nanoparticles was measured at –100...550 °C. The measurements for the irradiated samples were carried out in the temperature range of 0...550 °C.

Chiral microporous organic network/covalent organic framework/silica composites: Powerful and versatile chromatographic separation materials

Nowadays, covalent organic framework (COF) has shown great potential in chromatographic separation, and enriching the design of novel COF based stationary phases and broadening their application prospects remains of great significance. Microporous organic network (MON) is a novel type of porous material with large specific surface area and excellent stability connected by covalent bonding, which is extremely similar to COF. Especially, nano-sized MON has the characteristics of easy binding with silica matrix and superior chromatographic separation performance. In this work, the combination of MON and COF as the surface modification materials of silica gel was first explored. The conjugated network structure of MON and COF can improve the permeability of silica stationary phase, and the presence of abundant functional groups in COF and MON can enhance the separation ability for a series of aromatic compounds. Moreover, hydrophilic L-cysteine containing thiol group was cleverly introduced into MON/COF@SiO2via thiol-ene/yne click reactions to balance the hydrophilicity and hydrophobicity of stationary phase. The L-cysteine modified chiral MON/COF@SiO2 (CMON/CCOF@SiO2) was used for effective separation of various chiral/hydrophilic/hydrophobic analytes, and the CMON/CCOF@SiO2 was observed to exhibit superior separation ability to the CCOF@SiO2. Multi-mode chromatographic separation mechanisms were explored, demonstrating that multiple interactions were involved in the separation process. Finally, the CMON/CCOF@SiO2 was applied to detect the environmental endocrine disruptors in the water sample and pyridoxine in the tablet sample, respectively, indicating a great potential for application in actual sample detection.

Detection of the stimulant clobenzorex using voltammetry and screen-printed electrodes: A simple and fast screening method for application in seized samples and oral fluid of drivers

Clobenzorex (CBZ) is a stimulant drug, recognized for its anorectic potential, legally used in some countries for obesity treatment. However, CBZ is banned in much of the world and has been often used illegally by drivers needing to stay alert for extended periods. Therefore, the rapid identification of CBZ in forensic samples is of paramount importance for public health and safety. In this context, we introduce an innovative electroanalytical screening method for detecting CBZ in seized tablet samples and human oral fluid using voltammetry with a graphite screen-printed electrode (SPE-Gr). The electrochemical detection was optimized in phosphate buffer solution (0.1 mol L−1, pH 7.0) using square wave voltammetry (SWV). The SPE-Gr combined with SWV exhibited a good stability of the electrochemical responses for CBZ detection, with a relative standard deviation of less than 5% across different days (N = 5) and using different SPEs (N = 3). A linear detection range of 2.5–100.0 μmol/L (R2 = 0.992) was achieved, with a low limit of detection (LOD) of 0.32 μmol L−1. Interference studies with other illicit drugs and adulterants confirmed the selectivity of the proposed method for CBZ detection. In addition, the presence of CBZ in seized tablet samples and authentic oral fluids, collected from drivers, was detected and identified using the proposed method, which results were also confirmed by HPLC-MS. Consequently, integrating SPE-Gr with SWV offers a reliable, rapid, sensitive, selective, reproducible, and direct approach for the preliminary qualitative and quantitative analysis of CBZ in forensic contexts. Furthermore, the proposed method provides an efficient oral fluid test for CBZ screening in drivers under the influence of drugs.

Electrochemical sensing for simultaneous determination of dopamine and acetaminophen based on ZIF-8@ZIF-67 derived Co/Mo2C embedded in N-doped carbon hollow nanocages

The exploration of an economical and efficient noble metal-free heterogeneous catalyst is of great significance for the construction of an electrochemical method for the simultaneous detection of Dopamine (DA) and acetaminophen (AC). In this paper, we employed a facile strategy to obtain Co/Mo2C nanoparticles embedded in nitrogen-doped carbon hollow nanocages (Co/Mo2C@N-C HNCs) heterogeneous structure by pyrolyzing ZIF-8@ZIF-67 precursor. The unique hollow structure ensures a fast electron transport channel, N doping regulates the local electronic structure of the catalyst, and the synergistic effect with Mo2C and Co nanoparticles provides more electrocatalytic active sites. The Co/Mo2C@N-C HNCs electrode separates the overlapping voltammetry peaks of DA and AC into two distinct voltammetry peaks (△E=200 mV), thereby selectively determining DA in the presence of AC and vice versa. The transfer coefficient (α) and electron transfer number (n) of DA and AC electrocatalytic oxidation were also studied. Using Co/Mo2C@N-C HNCs as electrode, an electrochemical sensor platform for the simultaneous detection of acetaminophen (AC) and dopamine (DA) was first constructed with linear range of 1–185 μM, and 1–100 μM and low detection limit of 0.35 μM and 0.46 μM for AC and DA, respectively. Satisfactory results have been obtained in the determination of human serum and acetaminophen tablets samples. DFT calculation reveals the molecular mechanisms for DA and AC interacting with the Co/Mo2C@N-C HNCs catalysts. This strategy provides a new idea for the selective determination of several analytes in complex substrates.

Use of E-Nose in inspecting the effect of processing type on the aroma of garlic (Allium Sativum L.): a critical hint in the quality assessment

Controlling the quality and health of foodstuffs is of great importance. The quality of foods like garlic is strongly influenced by the conditions of processing. Fungal infection is one of the most common hazards of garlic productivity that can affect its processing as well. This research aimed to use the E-Nose to investigate the aroma of garlic as a quality control factor influenced by different treatments such as type of processing, type of fungal infection, and time elapsed since the date of inoculation. The data was investigated and categorized through different methods such as principal component analysis (PCA), linear discriminant analysis (LDA), Support vector machine (SVM), and backpropagation neural network (BPNN). The Index of deterioration toughness increased during the monitoring period. In the analysis of the data related to the unprocessed whole (UW), dried slices (DS), garlic powder (PO), and garlic tablet (TA), the PCA included 55%, 75%, 47%, and 53% of the data, respectively. The LDA was able to classify the aroma of UW, DS, PO, and TA samples based on the TFI treatment with an accuracy of 90%, 93.33%, 88.89%, and 60%, respectively. Also, the BPNN classified the aromas of UW, DS, PO, and TA samples based on the TEI treatment with an accuracy of 90%, 95.6%, 72.2%, and 82.2%, respectively. The results revealed that the aroma alteration can be used as a comprehensive factor in the quality control of processed products. As well, the type of processing had significant effects on the severity of decay caused by fungal infection.Graphical

Changing trends in anabolic-androgenic steroid use within Scottish prisons: Detection, prevalence, and quantitation.

Anabolic-androgenic steroids (AASs) are a subclassification of image performance enhancing drugs (IPEDs). While AAS use is most prevalent among people in athletics, there is also high lifetime prevalence of AAS use among prisoners. This study reports the qualitative detection of AASs in seized samples from the Scottish prisons from 2019-2023. Additionally, methods were developed for the quantitative analysis of AASs using gas chromatography-mass spectrometry (GC-MS) and applied to 61 samples of tablets or powders seized from Scottish prisons between July 2022 and July 2023. Since 2022, there has been an increase in AAS detections in the Scottish prisons. Oxymetholone was the most prevalent AAS, followed by metandienone (methandrostenolone, methandienone), methyltestosterone, oxandrolone, mestanolone (methylandrostanolone), stanozolol, and androstenedione. Multiple AASs were found in 21 samples and 10 samples contained other drugs, including amitriptyline, sertraline, zopiclone, mirtazapine, sildenafil, etizolam, Δ9-tetrahydrocannabinol, and the synthetic cannabinoid MDMB-INACA. Most AAS samples were tablets (77.0%), although they were also detected in powders, herbal material, e-cigarettes, and a fragmented soap bar-type sample. There was a large variation in the concentration of AASs in the tablets and powders seized from the Scottish prisons, demonstrating AASs are another highly variable component of the polydrug use situation in prisons, the effects of which need to be examined further.

Intercalated graphitic carbon nitride-modified electrochemical sensor for improved quercetin detection in clinical applications

Novel voltammetric methodologies have been developed to facilitate the trace-level analysis of quercetin (QRT) using a graphitic nitride (g-C3N4) intercalated carbon sensor. The integration of g-C3N4 into the sensor matrix has enhanced its structural and surface properties, thereby increasing its sensitivity towards QRT detection. The catalytic behavior of g-C3N4 significantly influences the peak response observed for QRT. Systematic investigations were conducted to explore the influence of various parameters, such as scan rate, pH, pre-concentration time, modifier quantity, and analyte concentration, on the peak current response of QRT. Cyclic voltammetry was employed to evaluate the impact of the scan rate, which facilitated the determination of physicochemical parameters, including the heterogeneous rate constant (kₒ) and the number of electrons (n) involved in the electrochemical reaction. Additionally, the concentration effect of QRT was scrutinized using the Square Wave Voltammetry (SWV) technique, which exhibited superior detection sensitivity with a detection limit of 1.18 nM compared to existing methodologies. Furthermore, the g-C3N4/CPE was employed in real-time analysis of QRT in spiked urine samples and pharmaceutical tablet samples, showing satisfactory recovery results. The electrode also demonstrated good stability over multiple measurements, indicating that g-C3N4/CPE is a promising sensor for QRT detection.

Identification of MDA in seized ecstasy-like samples using atmospheric solids analysis probe mass spectrometry and machine learning

In this study, a total of 64 samples of ecstasy tablets seized during operations conducted within the State of Rio Grande do Sul – Brazil in 2021–2022 were analyzed. The instrumental analysis was performed using the Radian ASAP MS instrument with a single quadrupole mass spectrometer and an Atmospheric Solids Analysis Probe (ASAP) interface. Data preprocessing was conducted using MATLAB to improve data quality for subsequent chemometric analyses. Classification models seeking to identify samples containing MDA (3,4-methylenedioxyamphetamine) were developed using Linear Discriminant Analysis (LDA) with variable selection through the genetic algorithm (GA), stepwise (SW), and successive projections algorithm (SPA). Additionally, Partial Least Squares Discriminant Analysis (PLS-DA) models were explored. The GA-LDA model achieved an accuracy of approximately 95% for both training and testing sets, demonstrating its effectiveness in distinguishing between sample classes. It selected only five variables during model building. The SW-LDA model displayed exceptional performance in the training set, achieving 100% for all metrics. However, its accuracy for the testing set was slightly lower at 84.7%, suggesting potential overfitting due to the inclusion of numerous variables. The SPA-LDA model, while not the best performer in the testing set, selected variables that were more easily attributed to specific ions/fragments, aiding in the interpretation of results. Interpretation of selected variables revealed key m/z values associated with different compounds found in the samples, such as MDMA, cocaine, and amphetamine-related fragments. Notably, the SPA method selected six variables that played a crucial role in distinguishing between sample groups. These findings contribute to the advancement of forensic drug analysis and quality control processes.

A multianalyte LC-MS/MS method for accurate quantification of Nitrosamines in Olmesartan tablets

This research summaries the development, optimization and validation of liquid chromatography tandem mass spectrometric (LC-MS/MS) method for concurrent measurement of seven nitrosamines viz; NDMA, NDEA, NDIPA, NDPA, NEIPA, NMPA & NMBA in Olmesartan tablet. Controlling these nitrosamines at trace levels is imperative for ensuring the safety of drug substances and products for consumption. Various regulatory authorities stress the significance of utilizing highly sensitive analytical methods to precisely measure nitrosamines at trace levels. The method applied effective chromatographic separation and optimized parameters for mass spectrometric detection. Detection was carried out using APCI positive ion mode. Chromatographic separation was achieved using a Thermo Accucore PFP column (150 mm x 4.6 mm, 2.6 µ), with a simple gradient elution of mobile phase consisting of 0.1 % formic acid in water (mobile phase A) and methanol (mobile phase B). The total run time was 20 min, with a flow rate of 0.800 mL/min.The method was validated according to the International Council on Harmonisation (ICH Q2 (R2)) guidelines. The established method demonstrated excellent linearity (R2> 0.99) and sensitivity for all the nitrosamines. Detection and quantification limits were sufficiently low for trace nitrosamine levels having good S/N ratio. The method showed good accuracy in Olmesartan tablet samples, with recoveries ranges between 80 % to 120 %. The new analytical approach has exceptional repeatability and reliability, making it possible to precisely quantify the levels of seven nitrosamines in Olmesartan medoxomil tablets in a single analytical run.

Optimization and Evaluation of Column Efficiency in RP-HPLC Method for Pharmaceutical and Forensic Drug Analysis

Reverse Phase High Performance Liquid Chromatography (RP-HPLC) is an efficient and reliable technique employed in pharmaceutical and forensic analysis. The assay determination in pharmaceutical and certain molecular detection is performed using this technique. Performance of chromatographic columns play a central role in development of more efficient separation methods. It is one of the main component of system suitability testing in a chromatographic system. The column efficiency can be assessed by using various traditional methods and reproducible results can be evaluated using liquid chromatography We studied the column efficiency using RP-HPLC technique for pharmaceutical drug product Aceclofenac in a validated method. Two mobile phases combinations Acetonitrile: Methanol (80:20 v/v) and Acetonitrile: Methanol: Ammonia (225:50:1 v/v) were compared on C-8 Lichrospher RP-HPLC column for Aceclofenac and three tablet samples (30 ppm). The height equivalent to theoretical plate (HETP) referred as direct measure of column efficiency produced efficient results (530-545 and 190-230) for respective mobile phases. The lower HEPT is an indication of efficient elution in second mobile phase. The change in polarity as per pKa of the analyte may enhance elution and resolution. helpful in method development for pharmaceutical and forensic drug analysis using liquid chromatography.

Development of a new magnetic solid-phase extraction method prior to HPLC determination of naproxen in pharmaceutical products and water samples

In this study, a new magnetic solid phase extraction based on magnetic composite modified with biochar obtained from pumpkin peel was developed for the enrichment and extraction of Naproxen in lake water, tablet and urine samples. The effects of main parameters such as pH, extraction time, amount of adsorbent and sample volume, which affect magnetic solid phase extraction, were investigated. Under optimal conditions, intraday and interday precision values for naproxen were below 5.9, with accuracy (relative error) better than 7.0 %. The detection limit and preliminary concentration factor were 12 ng/mL and 10, respectively. The method proposed here can be used for routine analysis of naproxen in lake water, urine and tablets.