scholarly journals Simultaneous Determination of Preservatives in Dairy Products by HPLC and Chemometric Analysis

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Fatemeh Zamani Mazdeh ◽  
Sima Sasanfar ◽  
Anita Chalipour ◽  
Elham Pirhadi ◽  
Ghazal Yahyapour ◽  
...  
Keyword(s):  
Sodium Benzoate ◽  
Dairy Products ◽  
Limit Of Detection ◽  
Reversed Phase ◽  
National Standards ◽  
National Standard ◽  
Potassium Sorbate ◽  
Limit Of Quantitation

Cheese and yogurt are two kinds of nutritious dairy products that are used worldwide. The major preservatives in dairy products are sodium benzoate, potassium sorbate, and natamycin. The maximum permitted levels for these additives in cheese and yogurt are established according to Iranian national standards. In this study, we developed a method to detect these preservatives in dairy products by reversed phase chromatography with UV detection in 220 nm, simultaneously. This method was performed on C18 column with ammonium acetate buffer (pH=5) and acetonitrile (73 : 27 v/v) as mobile phase. The method was carried out on 195 samples in 5 kinds of commercial cheeses and yogurts. The results demonstrated insufficient separation where limit of detection (LOD) and limit of quantitation (LOQ) ranged from 0.326 to 0.520 mg/kg and 0.989 to 1.575 mg/kg in benzoate and sorbate, respectively. The correlation coefficient of each calibration curve was mostly higher than 0.997. All samples contained sodium benzoate in various ranges. Natamycin and sorbate were detected in a remarkable amount of samples, while, according to Iranian national standard, only sorbate is permitted to be added in processed cheeses as a preservative. In order to control the quality of dairy products, determination of preservatives is necessary.

scholarly journals Analytical Method Validation and Formula Optimization of Topical Nanoemulsion Formulation Containing Resveratrol

2021 ◽  
Author(s):  
Christofori Maria Ratna Rini Nastiti ◽  
Florentinus Dika Octa Riswanto
Keyword(s):  
Limit Of Detection ◽  
Aqueous Solubility ◽  
Reversed Phase ◽  
Hplc Method ◽  
Optimum Composition ◽  
Analytical Method Validation ◽  
Limit Of Quantitation ◽  
Diabetic Wounds

Resveratrol (RSV), a natural lipophilic phytoalexin, was reported as an antioxidant and anti-inflammatory agent, which has the potential to cure diabetic wounds. However, several studies suggested the limitation of RSV, such as poor aqueous solubility, poor stability, and poor oral bioavailability. To overcome the issues, RSV was formulated as a topical nanoemulsion. It is important to ensure the quality of the dosage form by evaluating RSV load in the nanoformulation and optimizing the formula. A reversed-phase HPLC method was developed and validated prior to the load determination of RSV in the nanoemulsion formulation. The composition of triacetin-eugenol, Kolliphor® RH 40, and Transcutol® was further optimized by employing a Box-Behnken Design (BBD) to achieve the optimum composition with expected viscosity and RSV load. The HPLC method for determining RSV load was successfully validated for parameters of selectivity with the resolution of 8.487, linearity and range (r = 0.9979), precision (0.12% of RSD), accuracy (109–110% of recovery), the limit of detection (0.574 µg/mL), and limit of quantitation (1.740 µg/mL). The result of formula optimization was promising, showing the optimum composition of triacetin-eugenol, Kolliphor® RH 40, and Transcutol® at 4.44 g, 30.97 g, and 11.39 g, respectively.

scholarly journals Determination of Vitamin K1 in Medical Foods by Liquid Chromatography with Postcolumn Reduction and Fluorometric Detection

2000 ◽  
Vol 83 (4) ◽  
pp. 957-962 ◽  
Author(s):  
George M Ware ◽  
G William Chase ◽  
Ronald R Eitenmiller ◽  
Austin R Long
Keyword(s):  
Limit Of Detection ◽  
Solid Phase ◽  
Sodium Bicarbonate Solution ◽  
Reversed Phase ◽  
Mean Value ◽  
Fluorometric Detection ◽  
Vitamin K1 ◽  
Limit Of Quantitation ◽  
Medical Foods

Abstract A liquid chromatographic (LC) method is described for the determination of vitamin K1 in medical foods. The sample is enzymatically digested with lipase and α-amylase and extracted with 1% sodium bicarbonate solution–isopropanol (1 + 1). After C18 solid-phase extraction, vitamin K1 is separated by nonaqueous reversed-phase LC, converted to the hydroquinone by postcolumn zinc reduction, and quantitated by fluorescence detection. The limit of detection is 8 pg (3 σ), and the limit of quantitation is 27 pg (10 σ) on column. Linear response ranged from 0.1 to 1.0 ng vitamin K1 (r = 0.9999). The mean recovery (n = 38) for all spiking levels was 101.6 ± 2.85%. Analysis of Standard Reference Material 1846, Infant Formula, gave a mean value of 0.95 ± 0.088 mg vitamin K/kg (K or K1?)(n = 31) with a coefficient of variation of 9.26.

scholarly journals Determination of 7B3 Residues in Cotton Plants by Liquid Chromatography/Mass Spectrometry

2009 ◽  
Vol 92 (1) ◽  
pp. 302-306 ◽  
Author(s):  
Xiao-Jing Yan ◽  
Xiao-Mei Liang ◽  
Yan-Jun Xu ◽  
Shu-Hui Jin ◽  
Dao-Quan Wang
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Limit Of Detection ◽  
Reversed Phase ◽  
Liquid Chromatography Mass Spectrometry ◽  
Chromatography Mass Spectrometry ◽  
Relative Standard ◽  
Limit Of Quantitation ◽  
Cotton Plants

Abstract A method was developed for the determination of 7B3 (12-propyloxyimino-1,15-pentadecanlactam), a novel macrolactam fungicide, by liquid chromatography/mass spectrometry (LC/MS) with positive electrospray ionization (ESI+). The method used a reversed-phase C18 column and acetonitrilewater (60 + 40, v/v) mobile phase. The quick, easy, cheap, effective, rugged, and safe method was used for extraction of 7B3 from cotton plants, which involved the extraction of 10 g homogenized sample with 10 mL acetonitrile, followed by the addition of 4 g anhydrous MgSO4 and 1.0 g NaCl. After centrifugation, 1 mL of the buffered acetonitrile extract was transferred into a tube containing 50 mg primary secondary amine sorbent and 100 mg anhydrous MgSO4. After shaking and centrifugation, the final extract was transferred to an autosampler vial for concurrent analysis by LC/MS. The results of 7B3 determined by LC/MS in the selective ion monitoring mode were linear, and the matrix effect of the method was evaluated. The average recoveries of 7B3 fortified at different levels were within 84.1100.2, and the relative standard deviations were <7.5 for all samples analyzed. The method limit of detection and the limit of quantitation values were 0.03 and 0.1 mg/kg, respectively. The proposed method was successfully applied to determine 7B3 residues in practical samples. This method is sensitive, accurate, reliable, simple, and safe.

scholarly journals HPLC determination of Escitalopram in tablet dosage forms

Pharmacia ◽  
2022 ◽  
Vol 69 (1) ◽  
pp. 21-24
Author(s):  
Stefan Balkanski
Keyword(s):  
Mobile Phase ◽  
Limit Of Detection ◽  
Reversed Phase ◽  
Dosage Forms ◽  
Relative Standard ◽  
Limit Of Quantitation ◽  
Phase Liquid ◽  
Tablet Dosage ◽  
Liquid Chromatographic

Purpose: A simple, specific, precise, and accurate reversed phase liquid chromatographic (RP-LC) method has been developed for the determination of Escitalopram in tablet dosage form. Methods: The chromatographic separation was achieved on a LiChrosorb C18, 250 mm x 4.6 mm, 5 μm column at a detector wavelength of 270 nm and a flow rate of 1.0 ml/min. The mobile phase was composed of methanol, acetonitrile (70:30 v/v). The retention time of Escitalopram was 5.49 min. The method was validated for the parameters like specificity, linearity, precision, accuracy, limit of quantitation and limit of detection. Results: The method was found to be specific as no other peaks of impurities and excipients were observed. The square of correlation coefficient (R2) was 0.9999 while relative standard deviations were found to be <2.0%. Conclusion: The proposed RP-LC method can be applied for the routine analysis of commercially available formulations of Escitalopram.

Assessment of microbial quality of industrial and traditional creams in Alborz province, Iran

2021 ◽  
Author(s):  
Monica Aghvami ◽  
Gholamreza Jahed Khaniki ◽  
Samira Shokri ◽  
Nahideh Jalali
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Dairy Products ◽  
National Standards ◽  
National Standard ◽  
Coliform Bacteria ◽  
Microbial Quality ◽  
Traditional Dairy Products ◽  
Milk And Dairy Products

Milk and dairy products play an important role in the human diet and society's health. The aim of this study was the assessment of the microbial quality of industrial and traditional breakfast cream in Alborz province, Iran. In this study, 40 different samples of breakfast cream (20 samples of traditional breakfast cream and 20 samples of industrial pasteurized breakfast cream) were collected randomly in Alborz province in 2018. Microbial quality tests were performed according to Iran National Standards on Coliforms, Escherichia coli, and Staphylococcus aureus, and then the collected data were analyzed. The microbiological examinations revealed that 43% of the samples were contaminated with coliform bacteria that 12 samples (60%) out of 20 samples of traditional cream, 5 samples (25%) out of 20 samples of industrial cream were higher than the allowable microbial limit of the national standard of Iran. About 15% of samples of traditional creams and 10% of industrial creams were contaminated with Escherichia coli. 10% of samples of traditional cream were contaminated with Staphylococcus aureus, which was not observed in industrial creams. High contamination with bacteria, needs using different methods to control microbial growth, including the promotion of sanitary awareness among laborers, the codification of microbial standards for traditional dairy products, training to staff for preparing the cream and disinfection of tools.

scholarly journals Optimization of Determination of Sucralose in Drink by HPLC

2019 ◽  
Vol 2 (3) ◽  
Author(s):  
Sang Li
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Flow Rate ◽  
High Performance ◽  
Detection Efficiency ◽  
Limit Of Detection ◽  
Reversed Phase ◽  
Operating Conditions ◽  
National Standards

To optimize the method for determination of Sucralose in drink by high performance liquid chromatography (HPLC). Using HPLC with RID, operating conditions were C18 reversed phase chromatograph column, 40:60 = methanol: 0.125% potassium hydrophosphate as mobil phase, measured at a flow rate of 0.8 mL/min. In the range of 20 ~ 400 mg L, with the concentration of Sucralose and corresponding peak area as standard, r = 0.9999, it has good correlation, the recovery of sucralose is 94~108%.The lower limit of detection of Sucralose was 0.0024 g/kg. This method not only meets the requirements of national standards, but also fast, sensitive, and environmentally friendly, improves the detection efficiency and safety of the detection of sucralose in drink by high performance liquid chromatography.

scholarly journals Determination of Nicotine in Libyan Smokers' Urine Compared with that of Nonsmokers using Reversed Phase – High Performance Liquid Chromatog-raphy (RP-HPLC)

2019 ◽  
Vol 34 (3) ◽  
pp. 172-180
Author(s):  
Galal Elmanfe ◽  
Suad K. Omar ◽  
Noreldin S.Y. Abdolla ◽  
Amna M. Hassan
Keyword(s):  
High Performance ◽  
Limit Of Detection ◽  
Cost Effective ◽  
High Performance Liquid Chromatog ◽  
Reversed Phase ◽  
Urine Samples ◽  
Average Value ◽  
Limit Of Quantitation ◽  
One Step

The aim of the present study was to evaluate the levels of nicotine in twenty urine samples taken from ten smokers and ten non-smokers in Libya. Each volunteer was required to complete a questionnaire before providing the urine sample. The evaluation of the nicotine concentrations was carried out by means of a simple, rapid, cost effective but reliable, one-step extraction technique-reversed-phase high-performance liquid chromatography which was developed and validated for this purpose. The criteria and factors taken into consideration for this evaluation and validation include the linearity, precision, accuracy, limit of detection, and limit of quantitation. The urine samples from the smokers presented nicotine concentrations in the range of 0.037-1.979 µg/ml, with an average of 0.663 µg/ml. The range of the nicotine concentrations in non-smokers, on the other hand, was from 0.017-1.331 g/ml, where 0.273 µg/ml is the average value. Statistical analyses show that the nicotine concentrations were very significant in the smoker samples in contrast with the nonsmoker samples

scholarly journals Liquid Chromatographic Determination of Nicarbazin in Feeds

2000 ◽  
Vol 83 (5) ◽  
pp. 1027-1038 ◽  
Author(s):  
Beverly J Krabel ◽  
David A Dickson ◽  
Alan G Zimmermann ◽  
Mark R Coleman
Keyword(s):  
Limit Of Detection ◽  
Chromatographic Determination ◽  
Reversed Phase ◽  
Linear Range ◽  
Limit Of Quantitation ◽  
Standard Linear ◽  
Sample Recovery ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract A new liquid chromatographic method has been developed for determination of nicarbazin in feeds. Approximately 40 g feed is extracted with 200 mL acetonitrile–water (80 + 20, v/v). An aliquot of the extract is filtered and assayed using a reversed-phase isocratic method that measures the 4,4′–dinitrocarbanilide moiety of nicarbazin at a wavelength of 340 nm. For medicated feeds, the method uses a standard linear range of 5 to 100 μg/mL. For lower levels, a linear range of 50 to 150 ng/mL can be used. The method has a limit of detection of 250 ng/g and a limit of quantitation of 500 ng/g in a 40 g feed sample. Recovery was 99.1%, with a range of 95.2 to 101.8%. In the typical U.S. dosing range of 27 to 113.5 g/ton, the precision of the method based on one analyst, one day, and 2 weighings ranged from 2.8% (113.5 g/ton) to 4.7% (27 g/ton).

scholarly journals Determination of Diazepam in Cream Biscuits by Liquid Chromatography

2004 ◽  
Vol 87 (3) ◽  
pp. 569-572 ◽  
Author(s):  
Priyankar Ghosh ◽  
Mudiam Mohanakrishna Reddy ◽  
Beedu Sashidhar Rao ◽  
Rajendra Kumar Sarin
Keyword(s):  
Retention Time ◽  
Mobile Phase ◽  
Limit Of Detection ◽  
Linear Regression Analysis ◽  
Internal Standard ◽  
Reversed Phase ◽  
Calibration Plot ◽  
Relative Standard ◽  
Limit Of Quantitation

Abstract An analytical procedure was developed for the detection and quantitation of diazepam in cream biscuits, which were used to commit crime. The method involves the extraction of diazepam with ethanol at room temperature, and the extract is filtered, evaporated to dryness, and redissolved in the mobile phase, methanol–acetonitrile–tetrahydrofuran–water (15 + 55 + 4 + 26, v/v). The separation is achieved on a C18 reversed-phase column with the mobile phase and diode array detection (λmax) at 230 nm. Medazepam is used as the internal standard is for quantification. The calibration plot for the determination of diazepam is based on linear regression analysis (y = 0.6687x + 0.0372; r2 = 0.995). The limit of detection for diazepam in the biscuit samples was estimated as 600 ng/mL. The limit of quantitation for diazepam was estimated as 1.75 μg/mL. The diazepam detected per piece of biscuit was found to be in the range of 0.27–0.45 mg. Pure diazepam was added to biscuit samples at 3 levels (100 and 500 μg/g, and 1 mg/g), and the recoveries were found to be 95%. The mean retention time of diazepam was 2.7 min and that of medazepam (IS) was 4 min. The relative standard deviations of the diazepam level in the biscuit samples were estimated to be 0.4% for retention time and 1.02% for peak area in intraday analysis, whereas the corresponding values were and 0.61 and 2.34% in interday analysis. The method is rapid and reliable for qualitative and quantitative analysis of cream biscuits laced with diazepam, and it can be used by law enforcement laboratories for routine analysis.

Liquid Chromatographic Method for Rapid Determination of Total Avermectin B1 and 8,9-Z-Avermectin B1 Residues in Apples

1995 ◽  
Vol 78 (2) ◽  
pp. 419-422 ◽  
Author(s):  
Janice A Cobin ◽  
Nelson A Johnson
Keyword(s):  
Chromatographic Method ◽  
Limit Of Detection ◽  
Solid Phase ◽  
Rapid Determination ◽  
Reversed Phase ◽  
Extraction Column ◽  
Liquid Chromatographic Method ◽  
Limit Of Quantitation ◽  
Liquid Chromatographic

Abstract A liquid chromatographic method has been developed and validated for the rapid determination of avermectin B1 and 8,9-Z-avermectin B1 residues in apples. The avermectins are extracted from the crop matrix with an acetonitrile–water–hexane mixture; the extract is cleaned up on an aminopropyl solid-phase extraction column. The avermectins are derivatized with trifluoroacetic anhydride and analyzed by reversed-phase liquid chromatography with fluorescence detection. Recoveries of avermectins from apples fortified with about 2–77 ppb avermectin B1a or 2-27 ppb 8,9-Z-avermectin B1a averaged 85%. The limit of quantitation is 2 ppb (signal- to-noise [S/N] ratio, 12) and the limit of detection is 1 ppb (S/N ratio, 6) for each analyte. The assay is a simple, rapid, and sensitive method for monitoring the total amount of avermectin residues in apples.

Sign in / Sign up

Export Citation Format

Share Document