This study introduces a combined HPLC and UV detection technique for the quantification of casticin in capsule and human plasma samples. The chromatographic separation was carried out utilizing a C18 column (150 mm & times; 4.6 mm & times; 5 mu m) at a temperature of 25 degrees C. Isocratic elution with a mobile phase comprising 60:40 v/v (methanol-0.05% formic acid) was employed. Flow rate was adjusted 1 mL/min. The analyte was determined at a wavelength of 258 nm, with a retention time of 14.7 +/- 0.01 min. The developed method underwent validation according to ICH criteria, covering specificity, linearity, precision, accuracy, detection and quantitation limits, as well as robustness. The linear range was determined to be 10-60 ng/mL for both capsule and spiked plasma specimens. The suggested technique was performed to the analysis of casticin in spiked human plasma and pharmaceutical preparations, yielding a recovery of 106.04% and demonstrating precision through intra-day and inter-day experiments with the highest relative standard deviation (RSD %) value of 4.94. Consequently, the technique was performed to the quantifying of human plasma specimens from in a patient taking medication containing casticin.

This study presents a combination of High Performance Liquid Chromatography (HPLC) and ultraviolet (UV) detection that provides the quantification of agnuside in human plasma specimens. Reverse-phase chromatographic separation was carried out with C18 column (150 mm x 4.6 mm x 5 mu m), at 25 degrees C with isocratic elution of the mobile phase containing methanol: 0.1% formic acid (35:65 v/v) at 0.6 mL/min flow rate. Experiments were carried out at a wavelength of 258 nm. The retention time of the analyte is 9.70 +/- 0.01 min. The developed technique was validated based on the International Conference on Harmonization guideline. The correlation coefficient of the technique was 0.9915, and the calibration range was 5-125 mu g/mL. The recovery value of the proposed method was found to be 101.4%, and the precision of the method was calculated as 6.35 with the highest RSD% value. A pharmacokinetic study was performed by administering agnuside to a healthy volunteer.

A novel simple and cost effective HPLC technique was presented for the quantification of selexipag (SLP) in human plasma sample and the technique's applicability to a pharmacokinetic investigation. Chromatographic separation was achieved with C1 8 (5 mu m 3 4.6 mm 3 150 mm) column, at 30 8C with isocratic elution, mobile phase composed of solution A (acetonitrile), and solution B (0.5% formic acid) (65:35 v/v) at flow rate 1.2 mL min-1. The linearity range is 10-150 ng mL-1. As sample preparation step human plasma was precipitated with acetonitrile and the detection was provided at 300 nm. The retention time is 8.20 +/- 0.02 min. LOD is found to be 3.3 ng mL-1 for drug. The method was applied to the analysis of SLP in human plasma with good recovery as 97.83%. Validation of the studied methods was carried out according to EMA guideline. The new method applied on a prototype pharmacokinetic study by administration of 800 mu g SLP to a healthy volunteer and parameters like AUC0-24, AUC0-infinity, Cmax, tmax, and t1/ 2 were assessed.

A simple, fast and selective analytical method has been developed for the simultaneous determination of allantoin and D-panthenol in cosmetic products containing Aloe vera extracts. The proposed method depends on reversed-phase liquid chromatography with isocratic flow profile of the mobile phase composed of acetonitrile-10 mM phosphoric acid (pH 2.5) (85:15, v/v), with a C18 column at 30 degrees C. The analytes were detected with UV-vis. detector at 210 nm. The injection volume was 20 mu L. The linearity ranges were found to be 0.2-20 and 0.1-10 mu g mL-1 for allantoin and D-panthenol, respectively. LOD values were found to be 0.07 mu g mL-1 and 0.03 mu g mL-1, LOQ values were found to be 0.2 and 0.1 mu g mL-1 for allantoin and D-panthenol, respectively. No interference was observed from concomitants. The developed method was applied to the analysis of 10 different type cosmetic products. It is foreseen that the method will be able to be used in order to carry out routine analysis, quality control and standardization in cosmetic products containing allantoin and D-panthenol.

In this investigation, an UFLC technique utilizing fluorimetric detection was reported for the analysis of Montelukast (MON) in plasma. The method involves pre-column derivatization using 4-bromomethyl-7methoxycoumarin (BrMmC). The calibration curve linear concentrations from 10 to 1000 ng/mL. The method exhibited an average recovery rate of 95.49%. The newly developed method was effectively utilized to assess the pharmacokinetics of Montelukast (MON) following the administration of a single 10 mg tablet to a healthy male volunteer.

A novel analytical method based on ultra-fast liquid chromatography using fluorimetric detector was developed and validated for determination of non-steroidal anti-inflammatory drugs (NSAIDs) (ibuprofen (IBP), etodolac (ETD), dexketoprofen (DKP), sodium diclofenac (SDCF), and naproxen (NPX) in tap water, urine and pharmaceutical samples. Precolumn derivatisation of targeted NSAIDs was carried out with 4-bromomethyl-7-methoxy coumarin (BrMmC) using dibenzo-18-crown-6-ether as reaction catalyst leading to the formation of a fluorescent compound. The obtained fluorescent compound of NSAIDs were measured at excitation wavelength as 325 nm, and emission wavelength of 395 nm. Optimum analytical conditions were carefully studied and improved. C18 column, with the dimensions of 4.0 x 100 mm and 3 mu m particle size, was used. Gradient elution with methanol: water 40:60; v/v (eluent A) and acetonitrile 100% (eluent B) were used as mobile phase and flow rate of 0.4 mL/min. The linearity range of the analytes were between 0.01-10.0 mu g mL(-1). Recovery values obtained from pharmaceutical preparations were found as 100.04%, 99.99%, 100.09%, 99.98% and 100.47% for IBP, ETO, DKP, SDCF, NPX, respectively. LOD values were found to vary between 0.00009 mu g mL(-1) and 0.00048 mu g mL(-1) in tap water, urine and pharmaceutical samples. The optimised technique was successfully applied for the determination of NSAIDs in tap water, urine, and pharmaceutical specimen. The specified NSAIDs were not found in real tap water samples.

An HPLC method with UV detection was developed for the determination of carnosic acid in human plasma and applied to a pharmacokinetic study after oral administration of Rosemary extract to a healthy volunteer. Sample preparation depends on liquid-liquid extraction with hexane. Chromatographic separation was achieved with C18 column (150 mm × 4.6 mm × 5 μm), at 25°C with isocratic elution, mobile phase composed of solution A (methanol), and solution B (2% o-phosphoric acid in water) (90:10, v/v) at flow rate of 1.0 mL/min. The analyte was detected at 230 nm. The retention time is 4.20 ± 0.03 min. The method was validated in terms of accuracy, precision, specificity, robustness and detection and quantification limits, in accordance with European Medicines Agency guidelines. LOD and LOQ were found to be 0.075 and 0.25 ng/mL, respectively. The method was applied to the analysis of carnosic acid in human plasma with good recovery as 91.7%. The plasma concentration-time profile and pharmacokinetic parameters: AUC0-t, AUC0-∞, Cmax, tmax, t1/2 were calculated according to the assays. The method can certainly be used for routine analysis of carnosic acid in human plasma after oral administration of Rosemary extract, and for phase I clinical studies and bioavailability-bioequivalance studies as well.

An ultra fast liquid chromatographic (UFLC) method using fluorimetric detection for the quantitation of Febuxostat (FEB) in human serum was developed by precolumn derivatization with 4-bromomethyl-7-methoxy coumarin (BrMmC). The derivatization was catalyzed with dibenzo-18-crown-6-ether to produce a fluorescent derivative which was determined through fluorescence measurement with excitation at 320 nm and emission at 395 nm wavelengths. A C18 column with 100 cm x 4.6 mm, 3 µm particule size was used for the UFLC separation procedure. A mixture of acetonitrile: methanol: 0.05 M aqueous ammonium acetate (pH 5.0) (40:40:20, v/v/v) was used as mobile phase. During the procedure, the flow rate was maintained at 0.5 mL/min. A calibration curve was then plotted as 0.005–3.0 µg/mL with a detection limit of 0.0022 µg/mL and quantification limit of 0.0073 µg/mL. The mean recovery to reveal the accuracy and relative standard deviation (RSD) that indicates the precision of the method were found out to be 85.20 % and less than 3.52 %, respectively. The utility of the new method has been demonstrated by measuring the pharmacokinetics of FEB by administration of 80 mg tablets to a healthy female volunteer, aged 42.

A simple, rapid, and precise high performance liquid chromatography (HPLC) method was developed to determine the flavonoid apigenin in cosmetic products containing chamomile extracts. A C18 column was used as stationary phase and 70:30 ethanol:water was used as mobile phase with a 1 mL/min flow rate and isocratic elution. The temperature was stabilized at 25 degrees C during the separation. The injection volume was 50 mu L. The apigenin peak was eluted at 4.15 +/- 0.4 min. The method was validated according to International Conference on Harmonisation (ICH) criteria in terms of linearity, limit of detection, limit of quantitation, selectivity, sensitivity, robustness, accuracy, and precision. The limits of detection and quantitation were 0.060 and 0.2 mu g/mL respectively. The linear range was from 0.2 to 20 mu g/mL. The relative standard deviation values for intraday and interday analyses were less than 1.64%. The developed procedure was applied to the analysis of various cosmetic products. It is expected that the method is suitable for routine analysis, quality control and standardization of cosmetic products for apigenin.

This research presents a new, sensitive and selective UPLC method with fluorometric detection for the determination of sorafenib in human plasma and application of the method to a pharmacokinetic study. Sorafenib was precolumn derivatized with 7-chloro-4-nitrobenzofurazan (NBD-Cl) and the separation of the fluorescent derivative was performed with a C18 column (50 mm x 2.1 mm, 1.7 mu m) at 40oC using a mobile phase composed of acetonitrile -0.1% trifluoroacetic acid in water (60:40, v/v) by isocratic elution with flow rate of 0.5 mL min-1. The injection volume was 7 mu L. The method depends on the measurement of the derivative using fluorescence detection (lambda ex = 398 nm, lambda em = 425 nm). The retention time of sorafenib was 3.10 +/- 0.02 min. The novel method was validated in accordance with ICH criteria by studying on the parameters such as specificity, linearity, precision, accuracy and robustness. The method was determined to be linear in a concentration range of 0.25-10 mu g mL(-1) with the correlation coefficient of 0.9995. Limit of detection and quantitation were found to be 0.075 and 0.25 mu g mL-1, respectively. Intraday and interday RSD values were less than 5.48%. The plasma concentration-time profile and pharmacokinetic parameters such as AUC0-t, AUC0-& INFIN;, Cmax, tmax, t1/2 were measured according to the assays. The proposed method is feasible to investigate the bioequivalence and bioavailability and routine analysis of the drug in plasma.

Biogenic amines (BAs) are group of substances that are formed from amino acids by decarboxylation or amination and transamination of aldehydes and ketones. They may have either aliphatic, aromatic or heterocyclic structure. Their quantity determines their effects, optimum amounts are essential for physiological functions, but excess of BAs causes various toxic effects through out human body. BAs are presented in a wide variety of fermented foods such as fish, meat, milk products and some kinds of beverages like wine, beer and some fruit juices. In order to quantify their intake by food products are important, the methods that provide determination of BAs in food products are a matter of priority. Mostly, liquid chromatographic (LC) methods are preffered. Their amine groups are able to be derivatized by so many fluorogenic reagents. It is possible to combine LC systems with UV-vis. absorption spectrometric, fluorimetric and mass spectrometric detectors. Due to the fact that BAs are important markers for food quality and important for health, in this article LC methods for the determination of BAs in foods were reviewed from 2012 to present.

In this study, a new, fast and sensitive HPLC method with fluorometric detection was developed for the determination of mesalazine in human plasma and applied to a pharmacokinetic study. Mesalazine was precolumn derivatized with NBD-Cl and the fluorescent derivative was separated on a C18 (150 × 4.6 mm × 2.6 μm) analytical column at 30 ºC using a mobile phase composed of acetonitrile—0.1% o-phosphoric acid in water (70:30, v/v) by isocratic elution with flow rate of 1.0 mL min−1. The method was based on the measurement of the derivative using fluorescence detection (λex = 280 nm, λem = 325 nm). The retention time of mesalazine is 3.08 ± 0.06 min. Nortriptiline was used as internal standard. This currently developed method was validated according to ICH criteria by evaluating the specificity, linearity, precision, accuracy and robustness. The method was determined to be linear in a concentration range of 0.25–1.5 μg mL−1 with the correlation coefficient of 0.9997. LOD and LOQ were found to be 0.075 and 0.25 μg mL−1, respectively. Intraday and interday RSD values were less than 5.92%. The plasma concentration–time profile and pharmacokinetic parameters such as AUC0–t, AUC0–∞, Cmax, tmax, t1/2, were calculated according to the assays. The presented method can certainly be used for bioequivalence and bioavailability investigations and routine analysis of the drug in plasma.

Recent studies suggest that dysbiosis in chronic kidney disease (CKD) increases gut-derived uremic toxins (GDUT) generation, leads to systemic inflammation, reactive oxygen species generation, and poor prognosis. This study aimed to investigate the effect of oligofructose-enriched inulin supplementation on GDUT levels, inflammatory and antioxidant parameters, renal damage, and intestinal barrier function in adenine-induced CKD rats. Male Sprague-Dawley rats were divided into control group (CTL, n = 12) fed with standard diet; and CKD group (n = 16) given adenine (200 mg/kg/day) by oral gavage for 3-weeks to induce CKD. At the 4th week, CKD rats were subdivided into prebiotic supplementation (5g/kg/day) for four consecutive weeks (CKD-Pre, n = 8). Also, the control group was subdivided into two subgroups; prebiotic supplemented (CTL-Pre, n = 6) and non-supplemented group (CTL, n = 6). Results showed that prebiotic oligofructose-enriched inulin supplementation did not significantly reduce serum indoxyl sulfate (IS) but did significantly reduce serum p-Cresyl sulfate (PCS) (p = 0.002) in CKD rats. Prebiotic supplementation also reduced serum urea (p = 0.008) and interleukin (IL)-6 levels (p = 0.001), ameliorated renal injury, and enhanced antioxidant enzyme activity of glutathione peroxidase (GPx) (p = 0.002) and superoxide dismutase (SOD) (p = 0.001) in renal tissues of CKD rats. No significant changes were observed in colonic epithelial tight junction proteins claudin-1 and occludin in the CKD-Pre group. In adenine-induced CKD rats, oligofructose-enriched inulin supplementation resulted in a reduction in serum urea and PCS levels, enhancement of the antioxidant activity in the renal tissues, and retardation of the disease progression.

This article aims to present a simple and sensitive, HPLC–UV method, which was developed to determine carnosol in human plasma samples. Chromatographic separation was achieved with C18 column (150 mm × 4.6 mm × 5 μm), at 25 °C with gradient elution of the mobile phase consisting of methanol–water (2% o-phosphoric acid) at flow rate 1.2 mL/min. The analyte was detected at 230 nm by UV detector. The retention time of carnosol is 3.40 ± 0.01 min. This currently developed method was validated according to ICH criteria by evaluating the specificity, linearity, precision, accuracy and robustness. The method was determined to be linear in a concentration range of 1–20 ng/mL with the correlation coefficient of 0.9942. The proposed method was applied successfully to the analysis of carnosol in spiked human plasma with good recovery as 96.4% and the precision of the method was determined by intra day and interday assays with the highest RSD % values 5.71. The method successfully applied to a pharmacokinetic study with determination of Cmax, tmax, t1/2 and AUC, by administration of carnosol to a healthy volunteer.

In the current study, a new sensitive and precise method based on HPLC and derivatization with dansyl chloride was developed for quantification of deferasirox (DEF) in pharmaceutical dosage forms and spiked plasma samples. Separation procedure in the chromatographic system was performed using a mobile phase consisting of the mixture of methanol and acetic acid solution (0.5 M, pH adjusted to 7.0 with NaOH) with a ratio of 70:30 v/v at flow rate of 1.0 mL per minute under isocratic elution on a C18 column (150 mm x 4.6 mm, 5 mu m I.D.). The excitation wavelength was selected as 340 nm and emission wavelength was selected as 480 nm for the measurement of the analyte signal. The retention time for DEF is approximately 3.5 min. ICH Guidelines were taken into account for method validation. For the deferasirox concentration range of 20-2000 ng/mL, the proposed analytical method exhibited a linear relationship between the drug concentration and measured fluorescence with a correlation coefficient of 0.9994.The currently developed method can be implemented efficiently for the quantification of DEF in pharmaceutical dosage forms and spiked plasma samples.

A sensitive method is presented for the determination of the ticagrelor (TCG) in human plasma and pharmaceutical preparations using 5-(dimethylamino)naphthalene-1-sulfonyl chloride (dansyl chloride). Ticagrelor contains a secondary amino group which reacts with dansyl chloride in the presence of 0.5 M sodium bicarbonate (pH 10) to yield a highly fluorescent derivative that is measured at 445 nm after excitation at 340 nm. Different experimental parameters affecting the fluorescence intensities were carefully studied and optimized. The proposed method was also validated according to ICH guidelines. The fluorescence concentration plot was rectilinear over the range of 20.0-200.0 ng mL(-1), with a coefficient of determination of 0.9999 with a limit of detection (LOD) of 0.14 ng mL(-1) and the limit of quantitation (LOQ) of 0.46 ng mL(-1). The proposed method was applied successfully to the analysis of TCG in spiked human plasma and pharmaceutical dosage forms with good accuracy and precision.

Aim The purpose of this study was to prepare targeted cancer therapy formulation against insulinoma INS-1 cells and to study its effect on cell death with related mechanisms in vitro. Methods Polylactide-co-glycolide (PLGA) nano-micelles were used for preparation of esculetin nano-formulation (nano-esculetin). The cells were treated with nano-esculetin and free esculetin. Apoptotic and necrotic cell death percentages, cell proliferation, ATP and GTP reductions and insulin levels were investigated on insulinoma INS-1 cells for both free and nano-esculetin formulations. Results About 50 mg of PLGA was able to carry 20 mg esculetin in 20 ml of formulation. The obtained optimized formulation was 150 nm, with 92% encapsulation efficiency and a slow-release behaviour was observed during release studies. Nano-esculetin bearing 25, 50 and 100 mu g esculetin and free esculetin in equivalent doses successfully decreased cell viability. The prevailing cell death mechanism was necrosis. Along with cell proliferation, intracellular insulin and the ratio of ATP and GTP were decreased even with 12.5, 25 and 50 mu g esculetin bearing nano-formulation and its equivalent free esculetin. Conclusions The results revealed that esculetin is able to show its anti-tumor afficacy after loading to PLGA nano-micelles and nano-encapsulation intensifies its cytotoxic activity in vitro. Current study shows that esculetin and its nano formulations are promising agents in treatment of insulinoma.

Following the convenient, yet very powerful pathway to create designer extraction sorbent using sol-gel chemistry, a novel sol-gel phenyl/methyl/poly(dimethylsiloxane) sorbent coating was created on polyester fabric substrate for fabric phase sorptive extraction (FPSE) and was subsequently applied to monitor human exposure to selected polycyclic aromatic hydrocarbons (PAHs) including pyrene, chrysene, and benzo[a]pyrene in plasma samples obtained from tobacco smoker volunteers using high performance liquid chromatography fluorescence detector (HPLC-FLD). A rapid FPSE-HPLC-FLD method was developed that adequately resolved the PAHs chromatographically, after their successful extraction from human plasma using fabric phase absorption extraction (FPSE) and subsequently analysed in the liquid chromatographic system by means of an analytical column (InterSustain C-18 column 150 x 4.6 mm, 5 mu m) using acetonitrile (ACN) and water as mobile phases in gradient elution mode. With the optimized conditions, the retention times were found to be 6.168, 7.214, and 10.404 min for pyrene, chrysene, and benzo[a]pyrene, respectively. The total chromatographic runtime was limited to 12.5 min. The method, validated through the calculation of all the analytical parameters according to the International Guidelines, was applied to the analysis of real samples collected from informed volunteers. The proposed approach which included the use of sol-gel phenyl/methyl/poly(dimethylsiloxane) immobilized on hydrophobic polyester substrate and C18 stationary phase used in HPLC, has shown a high potential as a rapid tool for future clinical, forensic and toxicological applications, also in the light of the LOD and LOQ values comparable to those normally obtainable with more sophisticated, and expensive instruments that often require highly trained personnel. The results reported here further consolidate the application of FPSE in the analysis of biological samples for both diagnostic and analytical-clinical purposes.

Topical formulations of 18-beta glycyrrhetinic acid (18-beta GA) were designed for use in relieving inflammatory and painful conditions of the skin. Formulations were containing penetration enhancers that differ in penetration enhancing mechanisms. Anti-inflammatory effects of formulations and effects of penetration enhancers on penetration and permeation of the drug through rat skin were investigated. The total amount of 18-beta GA permeated from the base oil/water emulsion (53.19 +/- 22.25 mcg/cm(2) ) was approximately twice higher than the base oleaginous cream (29.17 +/- 3.85 mcg/cm(2)) while there was no 18-beta GA permeation from the base hydrogel formulation to the skin (p < 0.05). Incorporation of propylene glycol was generally found to increase 18-beta GA permeation to the skin. The highest oedema inhibiting activity was achieved in the oil/water emulsion containing propylene glycol followed by the base oil/water emulsion without a penetration enhancer (p < 0.05). This result was consistent with the ex vivo study. Limonene and oleic acid were found to be insufficient in 18-beta GA permeation to the skin.

Polybrominated diphenyl ethers (PBDEs), which are used as flame retardants, are widely used additives so many different kind of materials that are consumed by public. Current researches reveal a significant increase in the levels of PBDEs in human biological fluids all around the world. According to International Agency for Research on Cancer (IARC), PBDEs are declarated as carcinogenic agents and additionally a considerable risks have been shown in animal studies such as liver damage, alteration of thyroid hormone levels, neurotoxicity and hazardous effects on development of fetus. Due to the simplicity of human exposure routes such as ingestion, inhalation or dermal contact, it gains high importance to quantify PBDEs in biological fluids. The exposure to PBDEs is critic aspecially during pregnancy, fetus development and infancy. Excretion of PBDEs in human milk is the focus area for researchers in recent years. In this study, we reviewed current methodologies for the determination of PBDEs in human milk including sample preparation step, analytical procedure, validation parameters and observed levels of PBDEs in human milk. Because of the high physico-chemical stability of PBDEs, they have long persistence in human body. Besides, they reside in the lipid fractions of tissues because of their hydrophobic characteristics. Human breast milk has high lipid level, so that it is a suitable matrix for the accumulation and determination of PBDEs.