Journal of the Turkish Chemical Society Section A: Chemistry
The selection of the best mobile phase setup is one of the most important factors to be considere... more The selection of the best mobile phase setup is one of the most important factors to be considered prior to quantitative instrumentation of multiple pesticides. Usually, mobile phases comprises of water (A) and an organic solvent (B) are the setup used in liquid chromatography instruments for the analysis of pesticide residues in various samples. Unfortunately, most of the analysis are being carried out without optimization and selection of the best mobile phase setup to improve the sensitivity of the instrument. For that reason, the comparative analysis of the reportedly used mobile phases and some few suggested ones was carried out on the multi-pesticide mixture of 0.1 mg/kg (100 µg/kg) standard solutions and quantified with liquid chromatography-tandem mass spectrometry (LC-MS/MS) instrument. Consequently, the best mobile phases setup that resulted in the sum of average total chromatographic peak areas (ATCPAs) and average total chromatographic peak heights (ATCPH) for the total ...
White and red Allium cepa were individually analysed quantitatively for proximate compositions an... more White and red Allium cepa were individually analysed quantitatively for proximate compositions and flavonoids % in dried grinded bulbs. All results were presented as mean + standard deviation of three replicates; white and red Allium cepa contained 89.62 + 0.83 and 88.48 + 0.03% moisture, 3.33 + 0.56 and 3.17 + 0.29% ash, 2.17 + 0.29 and 6.50 + 1.00% crude lipid, 3.22 + 0.07 and 3.02 + 0.29% crude protein, 3.83 + 0.29 and 2.83 + 0.29% crude fibre, 87.44 + 0.24 and 84.48 + 0.93% available carbohydrate, 382.11 and 408.5 kcal/100g energy value, as well as 64.0 + 0.93 and 61.20 + 0.24% flavonoids, respectively. Hence, this research justifiably proved that both species would provide flavouring, nutritional and medicinal importance. Thus, the white Allium cepa possessed a more nutritional and medicinal properties than the red but provides less energy and lower resistance to storage.Keywords: Allium cepa, Flavonoids, Proximate, Sokoto, Spice
The rice husk was characterized by proximate and ultimate analysis. The proximate analysis was de... more The rice husk was characterized by proximate and ultimate analysis. The proximate analysis was determined by moisture, volatile and ash content as 15.48%, 57.28% and 15.35% respectively. Ultimate analysis was determined using the data obtained from proximate analysis to calculate carbon, hydrogen, nitrogen and oxygen percentage as 43.67%, 4.64%, 0.956% and 35.78% respectively. The rice husk pyrolysis was studied by TGA/DTG analysis in a nitrogen atmosphere at flow rate of 60mL/minute, heating from 20.00 oC to 1000.00 oC at three different heating rates: 10, 15 and 20 oC/minute. The devolatilization and decomposition pattern portray by TGA curve for all the samples were almost the same, however, different peak temperatures were shown by DTG curve differently for all the samples at different heating rates. The sample RHC ran at three different heating rates: 10, 15 and 20 oC/minute with peak temperatures of 260.85 oC, 318.14 oC and 358.57 oC respectively. While the acid modified sampl...
The development of the best efficient technique for multi-pesticide determination in food samples... more The development of the best efficient technique for multi-pesticide determination in food samples is one of the best ways to address issues concerned with the use of pesticides in agricultural practices. Even though, several conventional techniques have been used earlier such as solid-phase extraction (SPE) and liquid phase microextraction (LPME), unfortunately, these treatment techniques possess poor sensitivity towards targeted analytes due to lack of modifications and optimization which provides an optimum condition for the analyses. In the present work however, chemometrics (multivariate) approach was used as response surface methodology (RSM) for optimising significant factors of quick, easy, cheap, effective, rugged and safe (QuEChERS) with the dispersive solid phase extraction (dSPE) technique. The Blanket-Burman (screening) and Box-Behnken (optimising) design generated by Minitab statistical software were used for the screening and optimisation of significant factors, respectively as well as quantification using total chromatographic peak areas (TCPA) responses of high-performance liquid chromatography-tandem mass spectrometry instrument. Eventually, the acquired average TCPA recovery (56%) for the RSM optimized QuEChERS-dSPE technique was favoured over that of default technique (44%) after comparative studies. This justifies the validity of the optimized method to play an important role in the determination of multi-pesticide residues in water and other food samples with higher matrix interferences.
The use of Tartrazine and other forms of azo dyes as colorants in food and beverages is on the in... more The use of Tartrazine and other forms of azo dyes as colorants in food and beverages is on the increase rate despite their problems upon consumption by humans. This could be due to availability and effectiveness in imparting color to the different substrates. Therefore, there is need to constantly monitor the concentrations of these dyes in our foods and beverages. Hence, this research work was conducted to determine the concentration level of tartrazine used as colorants in five different brands of beverages using spectrophotometric method of analysis. A cross sectional primary data was obtained through experimental processes from the 5 different samples of beverages obtained from Katsina Central Market and Tsohuwar Kasuwa Market in the city of Katsina, Katsina State – Nigeria. The research work however used UV-Visible Spectrophotrometric concept to investigate the level of the dye in the samples and compare it with the existing maximum permissible limits provided by the Authoritie...
Crinum ornatum (Toad’s onion) bulbs were analysed for its phytochemical and proximate composition... more Crinum ornatum (Toad’s onion) bulbs were analysed for its phytochemical and proximate composition. Toxicological test was also conducted on the water extract of the bulbs. Phytochemical screening revealed the presence of alkaloids, tannins, saponins, flavonoids, glycosides, cardiac glycosides, saponin glycosides, volatile oils and steroids. The results of the proximate analysis are expressed in percentage dry matter (mean + standard deviation of three replicates); Crinum ornatum contains77.83 + 2.75% moisture, 4.67 + 0.58% ash, 0.67 + 0.29% crude lipid, 4.04 + 0.07% crude protein, 2.67 + 0.29% crude fibre, 87.96 + 0.46% available carbohydrate and 373.99kcal/100g energy value. The medium lethal dose (LD50) of the bulbs’ is higher than 3000mg/kg for the tested animals. The results indicate that, the bulbs can be considered as a spice that could serve as potential sources of flavouring agent with medicinal benefits. Keywords : Crinum ornatum, Phytochemical, Proximate, Toxicity
Aflatoxins - Occurrence, Detection and Novel Detoxification Strategies [Working Title]
Mycotoxins are secondary metabolites present in foods which can cause adverse effects on humans a... more Mycotoxins are secondary metabolites present in foods which can cause adverse effects on humans and animals. Therefore, developing a simple, effective, sensitive and validated analytical method to monitor mycotoxins is essential. Sample preparation is an important step in the analysis of mycotoxins and other contaminants from complex food matrices. Food industries in developed and developing countries have faced serious challenges with contamination of mycotoxins especially aflatoxin in food and feed products. Thus, corn and cereal-based foods are mostly affected right from pre and postharvest periods. Owing to the complexity and structural nature of mycotoxins in foods and feeds there is an urgent need for simple, effective and environmentally friendly methods of sample preparation for the detection and quantification of aflatoxins in food samples. The paper reviews the application of the Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method for the analysis of aflatoxin...
The use of Sunset yellow as food colorants in non-alcoholic drinks, beverages and confectionery i... more The use of Sunset yellow as food colorants in non-alcoholic drinks, beverages and confectionery is rising despite their problems upon consumption by humans. It is therefore, necessary to constantly monitor the concentrations of these dyes in our foods, beverages and confectionery because of their health-related issues that include hyperactivity in children and immune system compromise. For these reasons, the concentration of sunset yellow used as colorants was determined in ten different brands of confectionaries using the spectrophotometric method of analysis. A cross-sectional primary data was obtained through experimental procedures in ten different samples of confectionary products procured (Central Market Katsina, Nigeria). The results shown that the concentration for the two samples; E and I are 52.311±0.178 mg/L and 87.887±0.018 mg/L respectively were found to be above the acceptable permissible limit of 50mg/L, while for the remaining eight samples; A, B, C, D, F, G, H, and ...
Journal of the Turkish Chemical Society, Section A: Chemistry, 2021
As a matter of fact, the Dietary Guidelines of the United States of America recommended the consu... more As a matter of fact, the Dietary Guidelines of the United States of America recommended the consumption of more fruits and vegetables to support the healthy condition of the body. Unfortunately, these food materials are being accumulated with pesticidal residues due to the continuous missmanagement and excessive application of the chemicals during pre and post-agricultural practices, which compels multiple analysis of pesticidal residues to know their concentration levels for the betterment of food security and safety. For that matter, multi-residues of Thiamethoxam, Propamocarb, Carbaryl, Metalaxyl, Baycarb, Thiobencarb, Diazinon, and Dursban pesticides were determined in the samples of lettuce, garlic, ginger, and bell-pepper using modified QuEChERS-dSPE Ionic Liquid-based dispersive liquid-liquid microextraction (DLLME) method coupled with LC-MS/MS instrument and validated (European Union Guideline). Resultantly, the accuracy (87-127%) and precision (0-22%) were mostly within the acceptable range for the former (70-120%) and latter (≤20%). Meanwhile, the limit of detections (0.01-0.28 µg/kg) and limit of quantitations (0.03-0.93 µg/kg) were satisfactory. The concentration range (5-400 µg/kg) of calibration curves for the evaluated linearity were linear with coefficient of regressions greater than 0.99. The matrix effects for all the analyzed samples were very weak and less effective (≤-86%). The range (1-25%) for the estimated measurement uncertainties were certifiable and acceptable (≤ 50%). Therefore, the sample preparation method prove effective as validated and useful for the multiple determination of pesticides residues in the analyzed vegetable samples, which are presumably safe for consumption against health issues.
The use of pesticides in agricultural practices is very vital but continuously accumulates in wat... more The use of pesticides in agricultural practices is very vital but continuously accumulates in water, moist soil and contaminate fruits and vegetables. This eventually leads to many health issues such as congenital diseases and different forms of cancers. For this reason, the validated (SANTE 11831-2017) method of quick, easy, cheap, effective, rugged and safe (QuEChERS) with the dispersive solid phase extraction (SPE) coupled with ionic liquid-based (IL-based) in dispersive liquid-liquid microextraction (DLLME) was used for sample preparation of coconut water to determine multiple pesticides (Dursban, Diazinon, Thiamethoxam, Metalaxyl, Thiobencarb, Baycarb, Carbaryl and Propamocarb) residue using high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) instrument. The results of accuracy for relative recoveries (84 - 134%) were satisfactory because 87.5% of results were within the recommended range (70 - 120%). The precision results range (0-19%) of relative standa...
The objective of this work is to provide a critical review of the use of ionic liquids in the mic... more The objective of this work is to provide a critical review of the use of ionic liquids in the microextraction of pesticide residues in fruits and vegetables. It includes an assessment of the advantages and limitations of current applications of ionic liquids in microextraction techniques. The review also aims to illustrate the impact of ionic liquids on the development of novel sorbent materials for analytical applications. The unique physicochemical properties of ionic liquids make them ideal sorbents in separation techniques. Their number of applications in analytical separation has increased considerably over the past 5 years. Therefore, this review focuses on the synthesis, purification, functionalization, and application of ionic liquids for pesticide residue analysis in fruits and vegetables with different sample preparation procedures, covering articles published in the literature since their first application in 2009.
Hollow fiber liquid-phase microextraction (HF-LPME) techniques coupled to chromatographic systems... more Hollow fiber liquid-phase microextraction (HF-LPME) techniques coupled to chromatographic systems have been widely used for extraction and determination of diverse compounds. HF-LPME was able to provide better results in precision, accuracy, selectivity and enrichment factor, in addition to reduction of matrix effect and carry over. It is applicable within a wide pH range and compatible with most analytical instruments which enable the utilization of HF-LPME in a wide variety of applications. This review focused on the modified HF-LPME techniques, efficiency, comparison to other LPME methods and applications.
Food quality and food safety are major challenges affecting agricultural and industrial aspects o... more Food quality and food safety are major challenges affecting agricultural and industrial aspects of production. Many contaminants from different sources contaminate foods and drinks, leading to disastrous health problems like gene mutations and cancer. Previously, many different methods have been used for the analysis of these contaminants. Liquid–liquid extraction (LLE) has been the most well-known conventional technique used, but its limitations are its tediousness, time required, and the use of large quantities of toxic organic solvents. These limitations have led to the search for other, efficient techniques that are more environmentally friendly. Hence, this review highlights recent advances in liquid-phase (single-drop, hollow fiber, and dispersive liquid–liquid) microextraction procedures for food and drink analyses. Such modifications can be justified for solving limitations associated with the traditional LLE method. The objective of this review is to serve as a reference pl...
Pesticides play vital roles in agricultural practices, but the nature and mishandling of the chem... more Pesticides play vital roles in agricultural practices, but the nature and mishandling of the chemicals have led to their accumulation in moist soil, vegetables and fruits. Thus, development of efficient methods for pesticides determination is one of the most important ways to address such challenges. Multivariate response surface methodology optimisation using Placket-Burman and Box-Behnken designs were respectively used for screening and optimisation of significant factors of quick, easy, cheap, effective, rugged and safe (QuEChERS) with dispersive solid-phase extraction (SPE). Consequently, the optimised QuEChERS-dSPE technique coupled with modified ionic liquid-based (IL-based) dispersive liquid-liquid microextraction was used for sample preparation before LC-MS/MS. The developed method was validated (SANTE 11831-2017) for multipesticide residues determination in samples of bananas, cabbages, tomatoes, oranges and onions. The precision results were satisfactory in terms of relative standard deviation (≤ 20%) as recommended. The results of accuracy for relative recoveries (82-137%) were satisfactory because 92.5% of results were within the recommended range (70-120%). The matrix effects in all the samples were very weak (less effective) (≤ − 80%). The linearity of the evaluated results was 5-400 µg kg −1 and regression coefficients (R 2) were > 0.99. The resulting limits of detection and quantitation were 0.02-0.32 and 0.07-1.06 µg kg −1 , respectively, and therefore satisfactory. Certifiably, the estimated measurement uncertainties range (1-16%) was acceptable (≤ 50%). Thus, the developed method could be reliable and suitable for routine determination of multiple pesticide residues in various vegetable and fruit samples.
Journal of the Turkish Chemical Society Section A: Chemistry
The selection of the best mobile phase setup is one of the most important factors to be considere... more The selection of the best mobile phase setup is one of the most important factors to be considered prior to quantitative instrumentation of multiple pesticides. Usually, mobile phases comprises of water (A) and an organic solvent (B) are the setup used in liquid chromatography instruments for the analysis of pesticide residues in various samples. Unfortunately, most of the analysis are being carried out without optimization and selection of the best mobile phase setup to improve the sensitivity of the instrument. For that reason, the comparative analysis of the reportedly used mobile phases and some few suggested ones was carried out on the multi-pesticide mixture of 0.1 mg/kg (100 µg/kg) standard solutions and quantified with liquid chromatography-tandem mass spectrometry (LC-MS/MS) instrument. Consequently, the best mobile phases setup that resulted in the sum of average total chromatographic peak areas (ATCPAs) and average total chromatographic peak heights (ATCPH) for the total ...
White and red Allium cepa were individually analysed quantitatively for proximate compositions an... more White and red Allium cepa were individually analysed quantitatively for proximate compositions and flavonoids % in dried grinded bulbs. All results were presented as mean + standard deviation of three replicates; white and red Allium cepa contained 89.62 + 0.83 and 88.48 + 0.03% moisture, 3.33 + 0.56 and 3.17 + 0.29% ash, 2.17 + 0.29 and 6.50 + 1.00% crude lipid, 3.22 + 0.07 and 3.02 + 0.29% crude protein, 3.83 + 0.29 and 2.83 + 0.29% crude fibre, 87.44 + 0.24 and 84.48 + 0.93% available carbohydrate, 382.11 and 408.5 kcal/100g energy value, as well as 64.0 + 0.93 and 61.20 + 0.24% flavonoids, respectively. Hence, this research justifiably proved that both species would provide flavouring, nutritional and medicinal importance. Thus, the white Allium cepa possessed a more nutritional and medicinal properties than the red but provides less energy and lower resistance to storage.Keywords: Allium cepa, Flavonoids, Proximate, Sokoto, Spice
The rice husk was characterized by proximate and ultimate analysis. The proximate analysis was de... more The rice husk was characterized by proximate and ultimate analysis. The proximate analysis was determined by moisture, volatile and ash content as 15.48%, 57.28% and 15.35% respectively. Ultimate analysis was determined using the data obtained from proximate analysis to calculate carbon, hydrogen, nitrogen and oxygen percentage as 43.67%, 4.64%, 0.956% and 35.78% respectively. The rice husk pyrolysis was studied by TGA/DTG analysis in a nitrogen atmosphere at flow rate of 60mL/minute, heating from 20.00 oC to 1000.00 oC at three different heating rates: 10, 15 and 20 oC/minute. The devolatilization and decomposition pattern portray by TGA curve for all the samples were almost the same, however, different peak temperatures were shown by DTG curve differently for all the samples at different heating rates. The sample RHC ran at three different heating rates: 10, 15 and 20 oC/minute with peak temperatures of 260.85 oC, 318.14 oC and 358.57 oC respectively. While the acid modified sampl...
The development of the best efficient technique for multi-pesticide determination in food samples... more The development of the best efficient technique for multi-pesticide determination in food samples is one of the best ways to address issues concerned with the use of pesticides in agricultural practices. Even though, several conventional techniques have been used earlier such as solid-phase extraction (SPE) and liquid phase microextraction (LPME), unfortunately, these treatment techniques possess poor sensitivity towards targeted analytes due to lack of modifications and optimization which provides an optimum condition for the analyses. In the present work however, chemometrics (multivariate) approach was used as response surface methodology (RSM) for optimising significant factors of quick, easy, cheap, effective, rugged and safe (QuEChERS) with the dispersive solid phase extraction (dSPE) technique. The Blanket-Burman (screening) and Box-Behnken (optimising) design generated by Minitab statistical software were used for the screening and optimisation of significant factors, respectively as well as quantification using total chromatographic peak areas (TCPA) responses of high-performance liquid chromatography-tandem mass spectrometry instrument. Eventually, the acquired average TCPA recovery (56%) for the RSM optimized QuEChERS-dSPE technique was favoured over that of default technique (44%) after comparative studies. This justifies the validity of the optimized method to play an important role in the determination of multi-pesticide residues in water and other food samples with higher matrix interferences.
The use of Tartrazine and other forms of azo dyes as colorants in food and beverages is on the in... more The use of Tartrazine and other forms of azo dyes as colorants in food and beverages is on the increase rate despite their problems upon consumption by humans. This could be due to availability and effectiveness in imparting color to the different substrates. Therefore, there is need to constantly monitor the concentrations of these dyes in our foods and beverages. Hence, this research work was conducted to determine the concentration level of tartrazine used as colorants in five different brands of beverages using spectrophotometric method of analysis. A cross sectional primary data was obtained through experimental processes from the 5 different samples of beverages obtained from Katsina Central Market and Tsohuwar Kasuwa Market in the city of Katsina, Katsina State – Nigeria. The research work however used UV-Visible Spectrophotrometric concept to investigate the level of the dye in the samples and compare it with the existing maximum permissible limits provided by the Authoritie...
Crinum ornatum (Toad’s onion) bulbs were analysed for its phytochemical and proximate composition... more Crinum ornatum (Toad’s onion) bulbs were analysed for its phytochemical and proximate composition. Toxicological test was also conducted on the water extract of the bulbs. Phytochemical screening revealed the presence of alkaloids, tannins, saponins, flavonoids, glycosides, cardiac glycosides, saponin glycosides, volatile oils and steroids. The results of the proximate analysis are expressed in percentage dry matter (mean + standard deviation of three replicates); Crinum ornatum contains77.83 + 2.75% moisture, 4.67 + 0.58% ash, 0.67 + 0.29% crude lipid, 4.04 + 0.07% crude protein, 2.67 + 0.29% crude fibre, 87.96 + 0.46% available carbohydrate and 373.99kcal/100g energy value. The medium lethal dose (LD50) of the bulbs’ is higher than 3000mg/kg for the tested animals. The results indicate that, the bulbs can be considered as a spice that could serve as potential sources of flavouring agent with medicinal benefits. Keywords : Crinum ornatum, Phytochemical, Proximate, Toxicity
Aflatoxins - Occurrence, Detection and Novel Detoxification Strategies [Working Title]
Mycotoxins are secondary metabolites present in foods which can cause adverse effects on humans a... more Mycotoxins are secondary metabolites present in foods which can cause adverse effects on humans and animals. Therefore, developing a simple, effective, sensitive and validated analytical method to monitor mycotoxins is essential. Sample preparation is an important step in the analysis of mycotoxins and other contaminants from complex food matrices. Food industries in developed and developing countries have faced serious challenges with contamination of mycotoxins especially aflatoxin in food and feed products. Thus, corn and cereal-based foods are mostly affected right from pre and postharvest periods. Owing to the complexity and structural nature of mycotoxins in foods and feeds there is an urgent need for simple, effective and environmentally friendly methods of sample preparation for the detection and quantification of aflatoxins in food samples. The paper reviews the application of the Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method for the analysis of aflatoxin...
The use of Sunset yellow as food colorants in non-alcoholic drinks, beverages and confectionery i... more The use of Sunset yellow as food colorants in non-alcoholic drinks, beverages and confectionery is rising despite their problems upon consumption by humans. It is therefore, necessary to constantly monitor the concentrations of these dyes in our foods, beverages and confectionery because of their health-related issues that include hyperactivity in children and immune system compromise. For these reasons, the concentration of sunset yellow used as colorants was determined in ten different brands of confectionaries using the spectrophotometric method of analysis. A cross-sectional primary data was obtained through experimental procedures in ten different samples of confectionary products procured (Central Market Katsina, Nigeria). The results shown that the concentration for the two samples; E and I are 52.311±0.178 mg/L and 87.887±0.018 mg/L respectively were found to be above the acceptable permissible limit of 50mg/L, while for the remaining eight samples; A, B, C, D, F, G, H, and ...
Journal of the Turkish Chemical Society, Section A: Chemistry, 2021
As a matter of fact, the Dietary Guidelines of the United States of America recommended the consu... more As a matter of fact, the Dietary Guidelines of the United States of America recommended the consumption of more fruits and vegetables to support the healthy condition of the body. Unfortunately, these food materials are being accumulated with pesticidal residues due to the continuous missmanagement and excessive application of the chemicals during pre and post-agricultural practices, which compels multiple analysis of pesticidal residues to know their concentration levels for the betterment of food security and safety. For that matter, multi-residues of Thiamethoxam, Propamocarb, Carbaryl, Metalaxyl, Baycarb, Thiobencarb, Diazinon, and Dursban pesticides were determined in the samples of lettuce, garlic, ginger, and bell-pepper using modified QuEChERS-dSPE Ionic Liquid-based dispersive liquid-liquid microextraction (DLLME) method coupled with LC-MS/MS instrument and validated (European Union Guideline). Resultantly, the accuracy (87-127%) and precision (0-22%) were mostly within the acceptable range for the former (70-120%) and latter (≤20%). Meanwhile, the limit of detections (0.01-0.28 µg/kg) and limit of quantitations (0.03-0.93 µg/kg) were satisfactory. The concentration range (5-400 µg/kg) of calibration curves for the evaluated linearity were linear with coefficient of regressions greater than 0.99. The matrix effects for all the analyzed samples were very weak and less effective (≤-86%). The range (1-25%) for the estimated measurement uncertainties were certifiable and acceptable (≤ 50%). Therefore, the sample preparation method prove effective as validated and useful for the multiple determination of pesticides residues in the analyzed vegetable samples, which are presumably safe for consumption against health issues.
The use of pesticides in agricultural practices is very vital but continuously accumulates in wat... more The use of pesticides in agricultural practices is very vital but continuously accumulates in water, moist soil and contaminate fruits and vegetables. This eventually leads to many health issues such as congenital diseases and different forms of cancers. For this reason, the validated (SANTE 11831-2017) method of quick, easy, cheap, effective, rugged and safe (QuEChERS) with the dispersive solid phase extraction (SPE) coupled with ionic liquid-based (IL-based) in dispersive liquid-liquid microextraction (DLLME) was used for sample preparation of coconut water to determine multiple pesticides (Dursban, Diazinon, Thiamethoxam, Metalaxyl, Thiobencarb, Baycarb, Carbaryl and Propamocarb) residue using high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) instrument. The results of accuracy for relative recoveries (84 - 134%) were satisfactory because 87.5% of results were within the recommended range (70 - 120%). The precision results range (0-19%) of relative standa...
The objective of this work is to provide a critical review of the use of ionic liquids in the mic... more The objective of this work is to provide a critical review of the use of ionic liquids in the microextraction of pesticide residues in fruits and vegetables. It includes an assessment of the advantages and limitations of current applications of ionic liquids in microextraction techniques. The review also aims to illustrate the impact of ionic liquids on the development of novel sorbent materials for analytical applications. The unique physicochemical properties of ionic liquids make them ideal sorbents in separation techniques. Their number of applications in analytical separation has increased considerably over the past 5 years. Therefore, this review focuses on the synthesis, purification, functionalization, and application of ionic liquids for pesticide residue analysis in fruits and vegetables with different sample preparation procedures, covering articles published in the literature since their first application in 2009.
Hollow fiber liquid-phase microextraction (HF-LPME) techniques coupled to chromatographic systems... more Hollow fiber liquid-phase microextraction (HF-LPME) techniques coupled to chromatographic systems have been widely used for extraction and determination of diverse compounds. HF-LPME was able to provide better results in precision, accuracy, selectivity and enrichment factor, in addition to reduction of matrix effect and carry over. It is applicable within a wide pH range and compatible with most analytical instruments which enable the utilization of HF-LPME in a wide variety of applications. This review focused on the modified HF-LPME techniques, efficiency, comparison to other LPME methods and applications.
Food quality and food safety are major challenges affecting agricultural and industrial aspects o... more Food quality and food safety are major challenges affecting agricultural and industrial aspects of production. Many contaminants from different sources contaminate foods and drinks, leading to disastrous health problems like gene mutations and cancer. Previously, many different methods have been used for the analysis of these contaminants. Liquid–liquid extraction (LLE) has been the most well-known conventional technique used, but its limitations are its tediousness, time required, and the use of large quantities of toxic organic solvents. These limitations have led to the search for other, efficient techniques that are more environmentally friendly. Hence, this review highlights recent advances in liquid-phase (single-drop, hollow fiber, and dispersive liquid–liquid) microextraction procedures for food and drink analyses. Such modifications can be justified for solving limitations associated with the traditional LLE method. The objective of this review is to serve as a reference pl...
Pesticides play vital roles in agricultural practices, but the nature and mishandling of the chem... more Pesticides play vital roles in agricultural practices, but the nature and mishandling of the chemicals have led to their accumulation in moist soil, vegetables and fruits. Thus, development of efficient methods for pesticides determination is one of the most important ways to address such challenges. Multivariate response surface methodology optimisation using Placket-Burman and Box-Behnken designs were respectively used for screening and optimisation of significant factors of quick, easy, cheap, effective, rugged and safe (QuEChERS) with dispersive solid-phase extraction (SPE). Consequently, the optimised QuEChERS-dSPE technique coupled with modified ionic liquid-based (IL-based) dispersive liquid-liquid microextraction was used for sample preparation before LC-MS/MS. The developed method was validated (SANTE 11831-2017) for multipesticide residues determination in samples of bananas, cabbages, tomatoes, oranges and onions. The precision results were satisfactory in terms of relative standard deviation (≤ 20%) as recommended. The results of accuracy for relative recoveries (82-137%) were satisfactory because 92.5% of results were within the recommended range (70-120%). The matrix effects in all the samples were very weak (less effective) (≤ − 80%). The linearity of the evaluated results was 5-400 µg kg −1 and regression coefficients (R 2) were > 0.99. The resulting limits of detection and quantitation were 0.02-0.32 and 0.07-1.06 µg kg −1 , respectively, and therefore satisfactory. Certifiably, the estimated measurement uncertainties range (1-16%) was acceptable (≤ 50%). Thus, the developed method could be reliable and suitable for routine determination of multiple pesticide residues in various vegetable and fruit samples.
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Papers by Abubakar Lawal