Liquid Extraction Method Research Articles

Non-invasive Assay for Measurement of Fecal Triiodothyronine (T3) Metabolite Levels in European Mouflon (Ovis aries musimon)

Thyroid hormones (THs) are important indicators of metabolism and animal health. Traditionally, they have been determined from blood or urine samples. However, as their collection may be stressful and requires ethical approval, alternative non-invasive matrices are preferred when dealing with wild animals. Triiodothyronine (T3) is the active form of THs in blood and the major metabolite excreted in feces. This creates the ideal conditions for its assay in fecal samples. Fecal sampling eliminates the stress of the animals and the need to physically capture them. However, in wild species it is rare to find species-specific kits for the hormone assay. So, the objective of this work was to validate a method for the quantification of T3 metabolite (FTM) levels in feces of European mouflon by using an economic and easily available ELISA kit designed to quantify T3 in human plasma. Analytical and biological validations were performed in feces collected from 10 mouflons (5 ewes and 5 rams). An efficient liquid-extraction method was optimized. Precision, dilution linearity, parallelism, recovery and stability of T3 in fecal samples were calculated. Obtained data were considered acceptable according to international guidelines. The reliability of the results was verified comparing human plasma and mouflon fecal samples fortified with the same T3 standard solutions. The biological validation showed higher FTM levels in March compared to June, and no differences between mouflon ewes and rams. The validation of the present method provides a non-invasive and affordable tool for the quantification of FTM in European mouflon.

Determination of Rhodamine B by UV–Vis spectrophotometry in cosmetics after microextraction by using heat-induced homogeneous liquid–liquid extraction method

Determination of Rhodamine B by UV–Vis spectrophotometry in cosmetics after microextraction by using heat-induced homogeneous liquid–liquid extraction method

Exploiting bacterial isolates for diesel degrading potential under in vitro conditions

Hydrocarbon contaminated oil-spilled areas and oil-products have caused serious harm with increasing attention for development, implementation and removal of these contaminants. Bacterial diversity on succession at the petroleum hydrocarbon contaminated environment can give answer the problem. Such lands have serious problems as totally barren or with rare plantation. Bacteria can thereby be exploited for the mitigation of hydrocarbon to enhance the nutrient availability for vegetation. Present study involves collection of soil samples heavily contaminated with hydrocarbon from Bagru (Rajasthan). Samples were analysed by solid liquid extraction method followed by FTIR (Fourier Transform Infrared) and HPLC (High Performance Liquid Chromatography) analysis. During microbiological analysis hydrocarbon degrading bacteria were screened. FTIR spectral analysis indicated the presence of the functional group’s alkanes and aromatic ringed compounds; 43% to 69% hydrocarbon content recorded by HPLC analysis of all the soil samples respectively. From the soil samples six gram-positive and four gram-negative bacterial isolates were explored possessing hydrocarbon degrading capacities in the range 47.04-87.31% and 10.12-95.24% respectively. Growth kinetic studies revealed the degradation up to 1000 ppm diesel in 3 days under in vitro conditions. These bacteria can further be exploited for diesel degradation and will certainly propose a possible solution to the prevailing issue for its biodegradation in ex-situ conditions after up scaling.

Stable Carbon Isotope Analysis of Hexachlorocyclohexanes by Liquid-Liquid Extraction Gas Chromatography Isotope Ratio Mass Spectrometry: Method Evaluation and Applications.

Compound specific isotope analysis (CSIA) and enantiomer specific isotope analysis (ESIA) are powerful tools for assessing the fate of hexachlorocyclohexanes (HCHs) in the environment. However, there is no systematic study on the CSIA and ESIA analysis test methods of the carbon isotopes of HCHs in water and soil environments, in particular the isotope fractionation in the pre-concentration process. We endeavored to test the compatibility of CSIA and ESIA with the liquid–liquid extraction method of HCHs in water. The results showed that there were negligible changes in the δ13C of HCHs after extraction, indicating that liquid–liquid extraction can be used as a pre-concentration method for the determination of δ13C of HCHs in water. The optimized method was validated and then applied to differentiate three HCHs from different manufacturers, to identify in situ degradation of HCHs of groundwater from a contaminated site and to resolve the carbon isotope fractionation occurring in the α-HCH oxidation by CaO2/Fe(II) Fenton system. The results showed that the same reagents from different manufacturers have different carbon isotope compositions, and different isomers from the same manufacturer also have different isotope compositions, showing useful evidence in identifying the source of HCHs. The more enriched δ13C in the down-gradient wells indicated that HCHs have undergone biodegradation or/and chemical reactions in the groundwater system of the site. Carbon isotopic enrichment factors (εC) of −1.90 ± 0.10‰ were obtained in the oxidation process. Hence, the method validated in this study has great potential as a method for identifying the degradation of HCHs in a water environment.

Migration study of chemical additives from low density polyethylene (LDPE) into dahi.

Dahi is widely used fermented milk product in India. Low Density Polyethylene (LDPE) is the most extensively used packaging material for Dahi in India. The present study was conducted to develop the analytical methods for extraction and migration of chemical additives from LDPE into dahi. Characterization of dahi packaging materials collected from five different firms was done by Fourier Transform Infrared Spectroscopy. Focused ultrasound solid liquid extraction method was observed to be better as compared to solid liquid extraction method as the former extracted maximum additives from the LDPE. Out of total 76 chemical additives extracted from LDPE, only eight (10.52%) matched with the existing positive list of polyolefins prescribed by Bureau of Indian Standads (BIS). The overall migration of chemical additives from all the LDPE samples was below their maximum limit as given by BIS standards. Chemical additives which migrated into the simulants included the antioxidants, fatty acids and their derivatives, unreacted hydrocarbons, plasticizers, lubricants and surfactant etc.

Membrane extraction of V(V) by an oleic acid plasticized poly(vinyl chloride)/Aliquat® 336 polymer inclusion membrane

AbstractPolymer inclusion membranes (PIMs) have received much attention as a greener method than other liquid membranes for the separation of a great number of chemical species. The expected horizon of industrial applications besides the advantages of greener characteristics of PIMs than other liquid membranes and solvent extraction methods, have resulted in development of the new PIMs for specific tasks. In the presented study, a PIM composed of polyvinyl chloride, Aliquat® 336, and oleic acid (50/40/10 wt%, respectively) is fabricated and its characteristics are studied. Membrane segments (3.5 cm diameter, 0.110 ± 0.013 g) can extract 73% of V(V) (initial concentration 50 mg L−1) from 50 ml Na2SO4 solution (0.1 M) adjusted to pH 2.5 after 8 h shaking. The extraction is proceeded by an anion exchange mechanism in which chloride anion of the extractant is replaced by VO2SO4−. It is approved that ~97% of the extracted amount of V(V) is back‐extracted from the loaded PIMs by contacting them, for 24 h, with 50 ml 7 mol L−1 H2SO4/0.25 v/v% of H2O2. The PIM extracts selectively V(V) from the simulated solutions like that obtained by digestion of spent alumina hydrodesulfurization catalysts.

Evaluation of 186WS2 target material for production of high specific activity 186Re via proton irradiation: separation, radiolabeling and recovery/recycling

Abstract Enriched tungsten disulfide (186WS2) was evaluated at increasing proton beam currents (20–50 μA) and times (up to 4 h) on a GE PETtrace cyclotron for production of high specific activity (HSA) 186Re. The HSA 186Re was separated from the irradiated target as [186Re][ReO4]– by a liquid–liquid extraction method and radiolabeled with a new N2S2 ligand (222-MAMA-N-ethylpropionate). The enriched 186W was recovered from the extraction process, analyzed for purity and enrichment, and converted back to the disulfide (186WS2). The results demonstrate that the 186WS2 is an easily pressed target material that can withstand relatively high currents and can be readily recovered and recycled. The 186Re produced was isolated in high specific activity and readily formed the radiotracers [186Re][ReO(222-MAMA-N-ethylpropionate)] and [186Re][Re(CO)3(OH2)3] +.

Polyphenols in fig: a review on their characterisation, biochemistry during ripening, antioxidant activity and health benefits

SummaryFig fruit (consumed either fresh or dried) is a rich source of polyphenols distributed throughout its peel and pulp. However, the peel part is superior in diversity of these compounds in comparison to the pulp. Fig polyphenols have been extracted both by conventional solid–liquid extraction and novel assisted methods (mainly ultrasound‐assisted and microwave‐assisted procedures). These can be characterised primarily into flavonoids (anthocyanins, flavan‐3‐ols and various flavonol glycosides) and phenolic acids. Figs contain good levels of anthocyanins (such as cyanidin‐3‐O‐glucoside, cyanidin‐3,5‐diglucoside and cyanidin‐3‐O‐rutinoside) which impart different colouring hues to these fruits during the ripening process. Moreover, fig polyphenols have associated antioxidant activities and impart many health benefits such as antihyperglycaemic, hepatoprotective and antispasmodic activities. This review provides a thorough information on the fig polyphenols, stressing on their extraction, characterisation as well as quantification, the biochemical changes during the ripening process, associated antioxidant activity and health benefits.

A novel cascade approach to extract bioactive compounds from officinal herbs

This research aims to compare a novel cascade extraction method with a conventional solid–liquid extraction method, both assisted by ultrasounds. The cascade extraction method consists of a sequential series of extractions performed with the same hydroalcoholic solvent, which is reused from one herb to the other. In practice, a hydroalcoholic solution is firstly used to extract one botanical herb. The resulting extract is then reused for the extraction of a second herb. The process is repeated as many times as the number of herbs composing the final formulation. The main advantage of this approach is firstly the lower need of solvents compared with the individual extraction procedures, where a fresh solvent is needed on each extraction step. Furthermore, extracts of the two methods (solid liquid vs cascade extraction) were characterized with several antioxidant assays (DPPH, ORAC, and FRAP) and total phenolic content (TPC). The results show that the solid–liquid extraction method achieves similar yields to total phenols and similar TAC in comparison to the extracts obtained by the cascade extraction method. Also, the HPLC analysis of the extracts showed that both methods lead to similar chromatographic profiles either when analyzed by an electrochemical detector (CoulArray) or by a spectrometric diode array detector (DAD). However, our findings support the idea that the cascade extraction method obtains extracts richer of minor peaks, showing a more complex bioactive profile. Such results could be explained considering that the solvent used during the series of cascade extractions was enriched not only by antioxidants but also by plant surfactants, like saponins, which increase the solvent solubility. Overall, this research shows that the cascade extraction method can not only provide officinal herb extracts with similar phenolic yield and antioxidant capacity than conventional solid–liquid extraction but also with a more complex bioactive profile compared to traditional solid–liquid extraction and with a minor consumption of solvents.

Quantitative extraction of multiclass antibiotic residues in cow milk utilizing salting-out assisted liquid-liquid extraction followed by liquid chromatographic determination

ABSTRACT The salting-out assisted liquid–liquid extraction (SALLE) method with the liquid chromatography ultraviolet-visible detector (LC-UV) has been developed and validated for the simultaneous determination of seven antibiotic compounds of five different therapeutic classes (β-lactams), amoxycillin, ampicillin, penicillin G, (sulphonamides), sulfamethoxazole, (aminoglycosides) gentamicin, (fluoroquinolones) ciprofloxacin and (macrolide) erythromycin, in the cow milk samples. The LC conditions for separation of the selected antibiotic compounds were achieved with the reversed phase isocratic elution. The mobile phase consisted of 0.05 M Na2HPO4, acetonitrile and methanol (70:10:20 v/v/v). The mobile-phase flow rate was 1 mL min−1 with the injection volume of 20 μL and all the seven standard compounds were eluted within 14 min. The developed analytical method has been validated for the linearity, precision, sensitivity, accuracy, specificity, decision limit (CCα), and detection capability (CCβ). Experimental parameters influencing the extraction efficiency were evaluated and optimised. Under the optimum experimental conditions, good linearity over wide concentration ranges was obtained with the coefficient of determination R2 > 0.9989 for all the antibiotics. The limits of detection (LODs) and quantification (LOQs) ranged from 1.28 to 2.46 µg mL−1 and 3.87–7.46 µg mL−1, respectively. The relative standard deviations for the repeated analysis were below 8% indicating acceptable method precision. The accuracy study yielded satisfactory recoveries in the ranges 95.5–103% for the pure standard compounds and 83.8–112% for the spiked matrix-match milk samples. The results of the study revealed that the developed method is simple and fast and the SALLE method is appropriate for the simultaneous determination of targeted five multiclass antibiotic residues in the cow milk samples by LC-UV/Vis with a better efficiency.

α- Glucosidase Inhibitory and Antioxidant Activities of Moluccella aucheri (Boiss.) Scheen Extracts

Background & Objective: α-Glucosidase is one of the main enzymes in the intestinal absorption of carbohydrates. Inhibition of this enzyme can improve postprandial hyperglycemia in diabetic patients. Also, antioxidants can ameliorate diabetes complications resulted from oxidative stress. In this study α-glucosidase inhibition, antioxidant activity and total phenol content of different extracts and obtained fractions of Moluccella aucheri have been evaluated. Materials & Methods: The ethanol extract of aerial parts of M. aucheri was fractionated using liquid extraction method with petroleum ether, dichloromethane and ethyl acetate, respectively. The extracts and the resulting fractions of M. aucheri were tested against α-glucosidase enzyme from yeast using an in vitro colorimetric model at λ 405 nm. Antioxidant activity was assessed using two different methods, ferric reducing antioxidant power (FRAP) and the scavenging activity of DPPH radicals’ methods. Results: The screening results indicated that the antioxidant activity and total phenolic content of the methanol extract were potentially higher than ethanol extract, while the ethanol extract inhibited α-glucosidase enzyme to a greater extent. Ethyl acetate fraction illustrated potentially the highest antioxidant activity and phenolic content, but its inhibition activity against α-glucosidase was placed after the petroleum ether fraction. Two previously isolated methoxy flavones; genkwanin, 5-hydroxyl-7, 4'-dimethoxyflavone inhibited the α-glucosidase enzyme strongly. Conclusion: Since the ethyl acetate extract has both considerable antioxidant activity and α-glucosidase inhibitory activity, it may be considered as a potential crude drug for diabetes.

Development and greenness evaluation of solid-phase extraction and salting-out liquid–liquid extraction method for determination of herbicides in water, soil and rice

Development and greenness evaluation of solid-phase extraction and salting-out liquid–liquid extraction method for determination of herbicides in water, soil and rice

Presence and distribution of selected pharmaceutical compounds in water and surface sediment of the Golden Horn Estuary, Sea of Marmara, Turkey

The presence and distribution of ketoprofen, fenoprofen, diclofenac ibuprofen, naproxen, gemfibrozil, clofibric acid, estrone, 17β-estradiol, 17α-ethinylestradiol, and carbamazepine were investigated in water and surface sediment of the Golden Horn Estuary (Sea of Marmara, Turkey). Water samples were collected seasonally from different depths in nine sampling stations. Surface sediment samples were taken at four stations once a year. Liquid–liquid and solid-phase extraction (SPE) methods were performed on water samples. Sediment samples were extracted by ultrasonic extraction and then SPE method was applied for clean-up. Subsequently, all samples were analyzed by High-Performance Liquid Chromatography (HPLC). The most dominant compounds were found as gemfibrozil (<0.054-3.18 μg L−1), fenoprofen (<0.017-1.28 μg L−1), ibuprofen (<0.015-2.46 μg L−1) and 17α-ethinylestradiol (<0.010-1.49 μg L−1) in water samples. Only five of these eleven studied pharmaceuticals in surface sediments of the Golden Horn Estuary were able to identify. 17α-ethinylestradiol (319 ng g−1), fenoprofen (242 ng g−1), ibuprofen (215 ng g−1), gemfibrozil (124 ng g−1), carbamazepine (118 ng g−1) were detected in the surface sediments. Diclofenac, ketoprofen, naproxen, clofibric acid, estrone and 17β-estradiol were found below the method detection limits in surface sediments. Generally, the environmental concentrations of pharmaceuticals in water and surface sediment were much higher than those reported worldwide.

A Simple Method for the Determination of Polyphenolic Compounds from Grapevine Leaves

Grapevine leaves are photosynthetically the most active green organs providing carbohydrates that are of utmost importance for the regular vine’s metabolism and growth. Moreover, leaves are the pioneers of fungal infections caused by B. cinerea, E. necator, and P. viticola. Plant response to these microorganisms mostly depends on the content and composition of phenolic compounds abundantly found in the leaf’s outer tissues (epidermis, cuticle, trichomes). In order to obtain a satisfactory quantity of phenolic compounds, an experiment was conducted towards optimizing a solid–liquid extraction method. Variables were as follows: the type of organic solvent, the sample weight, the extraction temperature, and the extraction time. The optimal conditions were obtained by applying the response surface methodology. Therefore, by using acetonitrile as the organic solvent, conducting a single-step extraction at the temperature of 48 °C during the time period of 2 h and 25 min with a solid-to-solvent ratio of 1:56 g mL−1 (178 mg of leaves powder and 10 mL of extraction solvent) the optimal content of phenolic compounds was obtained. This protocol is reliable, fast, and relatively easy to perform for the determination of the abovementioned compounds.

The possibility of using DES based on polypropylene glycol 425 and tetrabuthylammonium bromide in the extraction processes of transition metals

Traditionally, the method of liquid extraction is used to extract metals from aqueous. This work is devoted to the combination of perspective alternative for hazardous solvents (aqueous two-phase systems based on water-soluble polymers) and the novel deep eutectic solvents in the non-ferrous metals extraction processes. In this work, the synthesis of deep eutectic solvent based on a water-soluble polymer (PPG-425) and tetrabutylammonium bromide (TBAB) by stirring for 10 minutes at 80° C has been shown. The obtained results showed not only the possibility of using DES in the metal extraction process, but the selectivity to the Fe(III) and Zn(III), the distribution coefficients were 71.64 and 25.17 respectively. The metal concentrations were determined spectrophotometrically using 4-(2-pyridylazo)resorcinol. This work shows the perspectives of using DESs in the metal extraction processes.

Extraction of Eu(III), Gd(III), and Tb(III) in aqueous two-phase systems based on polyethylene glycol 1500-NaNO3-H2O with the addition of extractants (D2EHPA, TBP, TOMAN)

Luminophores that used, for example, in fluorescent lamps, contain a large number of rare earth elements. Therefore, the processing of waste equipment containing luminophores is a rational approach to the obtaining of rare-earth metals, firstly, from the economics point of view, since they have a high cost, and secondly, from the ecological point of view, since environmental pollution will not occur. The cheapest way to extract rare earth elements from waste products is to dissolve them in strong acids and the following reprocessing by liquid extraction methods. In this case, neutral or ion exchange extractants (tributyl phosphate, di(2-ethylhexyl)phosphoric acid and quaternary ammonium salts) are used, which show high extraction ability and, in some cases, selectivity. Their applying is associated with the use of non-polar organic solvents, which contradicts the principles of «green» chemistry. A good and promising alternative to organic solvents can be aqueous two-phase systems, which have already proved themselves as low-toxic, but highly effective systems for the separation of a number of metals. Thus, in this work, we performed an experimental study of the interphase distribution of Eu(III), Gd(III), and Tb(III) in two-phase systems based on water-soluble polymers with or without the introduction of traditional organic extractants as an additive. The possibility of using such ATPS as a «green» solvent for traditional extragents for Eu(III), Gd(III), and Tb(III) extraction has been shown.

Natural green deep eutectic solvents-based eco-friendly and efficient extraction of flavonoids from Selaginella moellendorffii: Process optimization, composition identification and biological activity

In this study, ultrasound-assisted natural deep eutectic solvents (DES) were applied to extract total flavonoids (TF) efficiently and eco-friendly from Selaginella moellendorffii. Thirty natural DESs were prepared, of which choline chloride-lactic acid (ChCl-Lac) was selected as the optimal DES. Response surface methodology (RSM) was adopted to obtain the highest TF content from Selaginella moellendorffii by applying ChCl-Lac. A TF content of 5.72 ± 0.13 mg/g was obtained with water content of 24%, extraction power of 260 W, liquid/solid ratio of 24:1 mL/g and extraction time of 43 min. Compared with the ionic liquid extraction and traditional methods, DES-UAE was not only able to save time, but also increased TF content by nearly 2–3 times. Meanwhile, sixteen compounds in S. moellendorffii were identified through UPLC-Q-TOF-MS, and eight compounds were newly discovered. In addition, five biflavonoids in the TF extract were determined simultaneously adopting HPLC under optimal extraction conditions. The results of exploring in vitro biological activities of the TF extract using four antioxidant experiments indicated that the TF extract of S. moellendorffii exhibited potent antioxidant activities. Furthermore, the extract displayed antimicrobial activity against six bacteria, including Staphylococcus aureus, Micrococcus luteus, Bacillus subtilis, Proteus, Brucella and Shigella sonnei. For A549, HCT-116, HT-29, sw1990, HepG2 and HeLa cancer cells, the S. moellendorffii extract possessed apparent inhibition effects on the growth rate. All the results indicated that the DES, as an eco-friendly and efficient solvent, was suitable for extracting total flavonoids from S. moellendorffii.

Anti-IgE effect of small-molecule-compound arctigenin on food allergy in association with a distinct transcriptome profile.

Excessive production of IgE plays a major role in the pathology of food allergy. In an attempt to identify anti-IgE natural products, Arctium Lappa was one of the most effective herbs among approximately 300screened medicinal herbs. However, little is known about its anti-IgE compounds. To identify compounds from Arctium Lappa for targeted therapy on IgE production and explore their underlying mechanisms. Liquid-liquid extraction and column chromatographic methods were used to purify the compounds. IgE inhibitory effects were determined on IgE-producing human myeloma U266 cells, peanut-allergic murine model and PBMCs from food-allergic patients. Genes involved in IgE inhibition in PBMCs were studied by RNA sequencing. The main compounds isolated were identified as arctiin and arctigenin. Both compounds significantly inhibited IgE production in U266 cells, with arctigenin the most potent (IC50=5.09μg/mL). Arctigenin (at a dose of 13mg/kg) markedly reduced peanut-specific IgE levels, blocked hypothermia and histamine release in a peanut-allergic mouse model. Arctigenin also significantly reduced IgE production and Th2 cytokines (IL-5, IL-13) by PBMCs. We found 479 differentially expressed genes in PBMCs with arctigenin treatment (p<.001 and fold-change ≥1.5), involving 24gene ontology terms (p<.001, FDR <0.05); cell division was the most significant. Eleven genes including UBE2C and BCL6 were validated by qPCR. Arctigenin markedly inhibited IgE production in U266 cells, peanut-allergic murine model and PBMCs from allergic patients by down-regulating cell division, cell cycle-related genes and up-regulating anti-inflammatory factors.

Quantification and Ecological Risk Assessment of Colloidal Fullerenes Nanoparticles in Sediments by Ultrasonic-Assisted Pressurized Liquid Extraction and High Performance Liquid Chromatography.

Fullerenes engineered nanomaterials are regarded as emerging environmental contaminants. This is as their widespread application in many consumer products, as well as natural release, increases their environmental concentration. In this work, an ultrasonic-assisted pressurized liquid extraction (UAPLE) method followed by high performance liquid chromatography with ultraviolet-visible detector (HPLC-UV-vis) was developed for extraction and determination of fullerene in sediments. The method was validated and found to be suitable for environmental risk assessment. Thereafter, the method was used for the determination of fullerene (C61-PCBM) in sediment samples collected from Umgeni River, South Africa. The current method allows for adequate sensitivity within the linear range of 0.01–4 µg g−1, method limit detection of 0.0094 µg g−1 and recoveries ranged between 67–84%. All the parameters were determined from fortified sediments samples. The measured environmental concentration (MEC) of fullerene in the sediment samples ranged from not detected to 30.55 µg g−1. To the best of our knowledge, this is the first report on the occurrence and ecological risk assessment of carbonaceous fullerene nanoparticles in African sediments and biosolids.

An Liquid Chromatography-Tandem Mass Spectrometry Method for the Simultaneous Determination of Afatinib, Alectinib, Ceritinib, Crizotinib, Dacomitinib, Erlotinib, Gefitinib, and Osimertinib in Human Serum.

Routine therapeutic drug monitoring is a promising approach for the rational use of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) and anaplastic lymphoma kinase (ALK) inhibitors. The purpose of this study was to develop and validate a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous determination of 5 EGFR-TKIs (afatinib, dacomitinib, erlotinib, gefitinib, and osimertinib) and 3 ALK inhibitors (alectinib, ceritinib, and crizotinib). A 100-mL aliquot of serum was diluted with 100 μL of 1% aqueous ammonia containing internal standards and then purified using the supported liquid extraction method. LC-MS/MS was conducted in positive ionization mode, and the method was validated according to published guidelines. Calibration curves were linear across concentration ranges examined. The intra- and interassay accuracies were 90.7%-110.7% and 94.7%-107.6%, respectively. All intra- and interassay imprecision values were ≤10.1%. The EGFR-TKIs and ALK inhibitors examined in this study, except osimertinib, which could be stored on ice for at least 5 hours, were stable at room temperature for 3 hours. For the internal standard-normalized matrix factors, the mean recovery and percent coefficient of variation values ranged between 54%-112% and 1.7%-11.7%, respectively. This method successfully determined serum concentrations of afatinib, alectinib, erlotinib, gefitinib, and osimertinib in clinical samples. Serum levels of kinase inhibitors consistently reflected those reported in previous studies. An LC-MS/MS method suitable for the simultaneous determination of 5 EGFR-TKIs and 3 ALK inhibitors in serum was developed and validated. The newly developed method enabled the determination of 5 of 8 target drugs examined in clinical samples. However, a large number of clinical samples need to be analyzed to verify the usefulness of the method.