Browse

You are looking at 1 - 10 of 33,940 items for :

  • Chemistry and Chemical Engineering x
  • Refine by Access: All Content x
Clear All

Abstract

Dillenia indica is one of the important medicinal plants and is extremely popular in many systems of medicine including ayurvedic, homeopathic, and siddha. Traditionally, different parts of this plant have been used to treat cancer, wound healing, diabetes, diarrhea, bone fractures, abdominal pains, cuts and burns. In the present study, a simple, precise, accurate and validated high performance thin layer chromatographic (HPTLC) method was developed for simultaneous estimation of three pharmaceutically active compounds i.e., betulinic acid (BE), β-sitosterol (BT) and lupeol (LP) in fruits, leaves, root bark and stem bark of D. indica. Standards and plant samples were applied on TLC aluminum plate precoated with 0.2 mm layer of silica gel 60F254. The plate was run in a twin glass chamber comprising toluene:methanol:chloroform (8:1:1, v/v/v) as a mobile phase which resulted in better separation of compounds. The plates were immersed in anisaldehyde-sulfuric reagent and then heated at 105 °C for 5 min in CAMAG TLC plate heater for appearance of bands. Densitometric scanning was performed at λmax = 525 nm using tungsten light source in CAMAG TLC Scanner4 armed with WinCATS software. R F values of BE, BT and LP standards and those of plant samples were found to be 0.38 ± 0.01, 0.54 ± 0.01 and 0.65 ± 0.02 respectively. The method was further validated by following the International Conference of Harmonization (ICH) guidelines. For BE, BT and LP, the linear regression data for the calibration plots revealed a satisfactory linear association with correlation coefficients (r 2) = 0.9736, 0.9989 and 0.9957, respectively. Linear ranges for BE, BT and LP were 2,000–6,000 ng/band, 200–1,000 ng/band, and 200–600 ng/band respectively. Accuracy of the method was assessed by recovery study conducted at three different levels with the average recovery of 99.19, 99.69 and 100.95% for BE, BT and LP, respectively. The results exhibited the highest content of BE (0.148 ± 0.01%), BT (0.031 ± 0.01%) and LP (0.047 ± 0.01%) in stem bark. The developed method will be useful for routine and quality control analysis of fruits, leaves, root bark and stem bark of D. indica species.

Open access

Abstract

Artificial sweeteners are low-calorie substances used as food additives with aim to impart a sweet taste to beverages without adding significant calories. Due to the regulatory compliance regarding the type and the amount of artificial sweetener, and due to the large consumption of beverages and the effects of artificial sweeteners on human health, their identification and quantification is of a great importance. In this research simultaneous determination of acesulfame K (ACE-K), sodium saccharin (Na-SAC) and aspartame (ASP) as the most commonly used sweeteners in beverages was performed with a reversed – phase high performance liquid chromatography (RP – HPLC) with diode array detection (DAD). The best separation of the analytes was achieved on a Poroshell 120 EC-C18 (3.0 × 50 mm, 2.7 µm) column and isocratic elution with a mobile phase consisted of acetonitrile and diluted phosphoric acid (pH = 3.8) with 7/93 volume ratio (V/V), and flow rate of 1 mL min−1. The chromatographic process was followed at 195, 220 and 230 nm, under constant column temperature (25 °C). Under these chromatographic conditions, the total time of analysis was less than 5 min. The developed method was validated for linearity, precision, accuracy, limit of detection (LOD) and limit of quantification (LOQ). The LOD under established chromatographic conditions was 0.03, 0.07 and 0.17 mg L−1 for Na-SAC, ACE-K and ASP, respectively. The amount of artificial sweeteners in analyzed samples ranged from 30.32 to 148.37 mg L−1 for ACE-K, from 16.10 to 93.05 for Na-SAC, and from 6.06 to 512.72 for ASP. The validated method was successfully applied for determination of analytes in different commercially available beverages.

Open access

Abstract

People are consuming increasing amounts of poultry eggs and their products, and their safety is always a public concern. However, the complex composition of poultry eggs and their products, particularly the proteins and lipids, can easily cause matrix effects, requiring the use of sorbents to remove these components to avoid affecting the detection results. Zeolitic imidazolate framework-8 (ZIF-8) is a MOF material with high specific surface area, high porosity, and high stability, making it widely used as a sorbent in pesticide residue detection. In this study, we evaluated the performance of ZIF-8 compared to classic solid phase extraction (SPE) and Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) in the pretreatment step. The results showed that ZIF-8 could better reduce the matrix effect in poultry eggs and their products. After optimizing the extraction solvents, chromatographic and mass spectrometric conditions, and pretreatment processes, we established a method using ZIF-8 as a sorbent combined with high performance liquid chromatography–tandem mass spectrometry (HPLC-MS/MS) for the detection of 80 pesticide residues in seven different types of poultry eggs and their products, yielding satisfactory results. All the target analytes showed good linearity, both with values of r 2 > 0.996. The average recovery and coefficients of variation (CVs), expressed as relative standard deviations, ranges from 72.5% to 113.2% (chicken egg) (CV: 0.1%–12.9%), 72.2%–114.2% (salted duck egg) (CV: 0.1%–9.8%), 70.3%–105.6% (goose egg) (CV: 0.1%–12.0%), 70.9–120.4% (marinated egg) (RSD: 0.1%–14.8%), 70.7%–108.5% (duck egg) (CV: 0.1%–12.3%), 71.1%–105.0% (quail egg) (CV: 0.2%–5.6%), 70.7%–111.5% (century egg) (CV: 0.1%–13.4%). The values of limit of detection (LOD) and limit of quantification (LOQ) were, respectively, ranging from 0.15 to 0.85 μg kg−1 and 0.34–2.6 μg kg−1. When this method was applied to the detection of real samples, one chicken egg sample was found to contain 0.013 mg kg−1 of fipronil, and one marinated egg sample was found to contain 0.0087 mg kg−1 of thiamethoxam, indicating the necessity of stringent safety monitoring for poultry eggs and their products.

Open access
Acta Chromatographica
Authors:
Fouad Echerfaoui
,
Aimen El Orche
,
Khadija El Bourakadi
,
Abdelhafid Benomar
,
Casimir Adade Adade
,
Amine Laouni
,
Mounir El Kacemi
,
Mustapha Bouatia
, and
Miloud El Karbane

Abstract

Formaldehyde plays a significant role in the global economy due to its unique chemical properties and widespread use in both the medical field and various industrial sectors. However, formaldehyde (HCHO) is classified as a persistent organic pollutant and is known to be harmful. Exposure to formaldehyde, both direct and prolonged, can cause severe health issues and potentially lead to death. It is recognized as a human carcinogen by numerous organizations and can negatively impact the endocrine system, as well as having mutagenic or teratogenic effects. Formaldehyde has been detected in various matrices at levels exceeding those permitted by international health regulatory bodies. Chromatography, particularly high-performance liquid chromatography (HPLC) coupled with detection methods, is an analytical technique frequently used to determine volatile organic molecules, including formaldehyde. This investigation aimed to develop and validate an assay method to identify and quantify formaldehyde in cosmetic products using HPLC-PDA. The chosen isocratic system consisted of a ZORBAX RX-C8 column (250 mm × 4.6 mm; 5 μm) and a mobile phase mixture of acetonitrile and water in a 55:45 (v/v) ratio, with a flow rate of 1.5 mL min−1. Formaldehyde was detected at 353 nm after derivatization with a 0.1N 2,4-dinitrophenylhydrazine solution, with a retention time of approximately 5.0 min and a total run time of 7.0 min for formaldehyde. The method was validated according to ICH Q2 (R1) guidelines. The validation parameters demonstrated high selectivity, precision (RSD <2%), accuracy (mean recovery of 101.3%), linearity (r > 0.995 in the 1,000–2,400 ppm range), and a limit of quantification (LOQ) of 0.1 ppm. The validated analytical method was applied to 35 cosmetic products. None of these products were labeled as containing formaldehyde, although 6 imported products were labeled as containing formaldehyde-releasing preservatives. The results indicated that 88.6% of the samples tested positive for formaldehyde, with free formaldehyde levels ranging from 20 to 981 ppm. All samples contained formaldehyde levels below the 2000 ppm threshold.

Open access

Abstract

Currently, there are no reported green “high-performance thin-layer chromatography (HPTLC)” methods for domperidone (DOM) and cinnarizine (CNZ) simultaneous detection. The objective of the present study was to design and verify a reverse-phase HPTLC method for the concurrent analysis of CNZ and DOM in commercial tablets that is fast, sensitive, and greener. As a green mobile phase, acetone and water in an 80:20 (v/v) binary ratio were used to simultaneously determine CNZ and DOM. The stationary phase was reverse-phase silica gel 60F254S plates. Concurrent measurements of CNZ and DOM were performed at 230 nm. Four different tools were used to assess the greenness of the current method: AGREE, AES, ChlorTox, and NEMI. For both medications, the current approach was linear in the 25–1,000 ng/band range. The accuracy, precision, robustness, sensitivity, and environmental friendliness of the suggested technique for the CNZ and DOM simultaneous detection were verified. The new method's profile was noticeably greener, as seen by the results of every greenness tool, including NEMI, AES (89), ChlorTox (1.08 g), and AGREE (0.83). Utilizing the current approach, the amount of CNZ and DOM in pharmaceutical tablets was found to be 99.53 and 98.87%, respectively. These findings validate the suitability of the existing method for measuring CNZ and DOM simultaneously in commercial tablets. The results of the proposed study indicated that measuring CNZ and DOM in commercial products could be done consistently with the current methodology.

Open access
Acta Chromatographica
Authors:
Yangfan Du
,
Shunjun Ma
,
Dizhong Chen
,
Runrun Wang
,
Xianqin Wang
,
Congcong Wen
, and
Xiuwei Shen

Abstract

A fast, accurate, sturdy, and sensitive UPLC-MS/MS method was developed to measure the levels of ADB-BUTINACA in rat plasma for a pharmacokinetic study. The ADB-BUTINACA and midazolam (internal standard) were separated on a UPLC BEH C18 column (2.1 mm × 50 mm, 1.7 μm) using a gradient elution of acetonitrile and water (0.1% formic acid) as the mobile phase. ADB-BUTINACA and midazolam were detected in multiple reaction monitoring (MRM) mode for quantitative analysis, the mass detection was performed on a positive electrospray ionization (ESI) source. The calibration curve displayed excellent linearity from 1 to 1,000 ng mL−1, with a lower limit of quantification of 1.0 ng mL−1 and a limit of detection of 0.3 ng mL−1. The precision for both inter-day and intra-day assays was below 14%, while accuracy ranged from 92% to 111%. The method also showed an average recovery between 87% and 90%, with a matrix effect ranging from 104% to 111%. The data was acceptable according to the guidelines of the US Food and Drug Administration (FDA). This newly validated quantitative method successfully supported the pharmacokinetic study of ADB-BUTINACA.

Open access
Progress in Agricultural Engineering Sciences
Authors:
Szabolcs Homolya
,
Eszter Vozáry
,
Katalin Badak Kerti
,
Tímea Kaszab
,
Mohsen Mardani
, and
Anikó Lambert Meretei

Abstract

In the confectionery industry large quantities of palm fat in the fillings of chocolate products are used. Based on today's nutritional science results, it is desirable to replace palm oil with healthier fats. Oleogels can provide a kind of solution for this replacement. In our work the rheological, textural and thermal properties of oleogels containing high oleic sunflower oil, beeswax and monoglycerides were determined. In the samples we examined, the gelator concentrations were: 20% beeswax, 15% beeswax and 5% monoglyceride, 10% beeswax and 10% monoglyceride, 5% beeswax and 15% monoglyceride, and 20% monoglyceride. Based on our results, the oleogel containing 15% beeswax and 5% monoglyceride seems an eutectic crystal of beeswaxes and monoglyceride. It has relative high hardness, high storage modulus and high viscosity therefore it can replace the Chocofill filling fat, which contains mainly palm fat, used in large quantities in sweets.

Open access
Acta Chromatographica
Authors:
Barbara Johana González-Moreno
,
Sergio Arturo Galindo-Rodríguez
,
Luis Alejandro Pérez-López
,
Omar J. Portillo-Castillo
, and
Rocío Álvarez-Román

Abstract

The use of edible coatings (ECs) containing essential oils (EOs), such as that derived from the Thymus vulgaris plant (EO-Tv), offers a natural option for preserving and increasing the shelf life of fruit and vegetable products. However, considering their physicochemical properties, the incorporation of EOs into nanocapsules (NCs) represents an alternative to reduce their volatility and oxidation. In this way, quantitative determination of the EOs incorporated into NCs is necessary for simultaneous monitoring of their main components during the nanoencapsulation process, as well as for the future precise and accurate dosage of EO components in fruit and vegetable products. In this study, ECs were formed from NCs loaded with EO-Tv and sodium alginate (AL). The EO-Tv was characterized through GC-MS and GC-FID analysis, and it was found that the major component of EO-Tv was thymol, with an abundance of 30.91%. Subsequently, an analytical method based on HS-SPME-GC-FID was developed and validated for quantification of the EO-Tv encapsulated in NCs and incorporated into the EC. The method was found to be precise and accurate for quantification of the main components of EO-Tv in the formed EC. Once the analytical method was validated, it was established that the encapsulation efficiency was greater than 50% in the case of NC-EO-Tv purified via evaporation at reduced pressure. On the other hand, 35.78 μg cm−2 of thymol was quantified in the EC formed from the NCs and AL. The present work presents an analytical tool for simultaneous quantification of the main components of EO-Tv in NCs, as well as in the ECs formed with NCs, promoting its potential application in fruit and vegetable products.

Open access
Progress in Agricultural Engineering Sciences
Authors:
Fraz Ahmad Khan
,
Farzaneh Khorsandi
,
Muddassir Ali
,
Abdul Ghafoor
,
Rana Ahsan Raza Khan
,
Muhammad Umair
,
Shahzaib
,
Abdul Rehman
, and
Zahid Hussain

Abstract

The spray is the primary method to apply pesticides to the crops. To provide enough coverage and deposition on target surfaces, the drop size produced during spray application must be precisely calibrated; nevertheless, it must not be too tiny to cause the undesirable phenomena known as “spray drift”. Spray drift is the movement of droplets in the atmosphere during or after spraying. The negative effect of spray drift can harm human health, livestock, and adjacent crops or can cause environmental pollution. To address this problem, a lot of work has been done. Previous studies on spray drift reduction approaches including factors promoting drift, drift measuring technologies, drift prediction models, and drift reduction technologies, were reviewed in this paper. Based on the literature review, future research and developments are projected. This review may provide guidance and reference to researchers for further development and improvement in drift reduction technologies.

Restricted access
Acta Chromatographica
Authors:
Pooja Sharma
,
Sushil Ahlawat
,
Pooja Agroiya
,
Reena Chauhan
,
Nisha Kumari
,
Surender Singh Yadav
, and
Gajender Singh

Abstract

Sumiprempt containing Pyriproxyfen and fenpropathrin insecticides is used for pest control in okra crop. Pyriproxyfen can disrupt endocrine function, while fenpropathrin disrupts voltage-gated sodium channels in neurons. Based on their health risk to consumers and impact on environmental deposition, an experiment under field was planned to evaluate deposition, decontamination and related dietary risks. A methodology was developed and validated to identify and quantify the pyriproxyfen + fenpropathrin residues, extracted via QuEChERS method using GC-MS/MS. The foliar application of ready-mix formulation (Pyriproxyfen 5% + Fenpropathrin 15% EC) @ 750 gm mL−1 ha−1 and 1,500 gm mL−1 ha−1 leads average initial deposition pyriproxyfen 5% (0.359, 0.584 ppm) and fenpropathrin (0.643, 1.005 ppm) at respective doses. Residues reached below limit of quantification (0.01 ppm) on 15th and 20th day for pyriproxyfen and 10th and 15th day for fenpropathanin at the recommended and double the recommended doses, respectively. Dissipation followed the first-order kinetics with half-life value ranged in between 1.79–1.84 (pyriproxyfen) and 2.27–2.31 days (fenpropathrin) at the respective doses. The pre-harvest interval of 12 days was recommended for safe consumption of okra fruit. Even though all the decontamination treatments were successful in lowering the residues of both chemicals to substantial levels, washing followed by boiling was found to be the most effective treatment for reducing the residues. The risk quotient values were less than 0.01, implying that pyriproxyfen and fenpropathrin offer no dietary risk to consumers.

Open access