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Modern bioanalytical laboratories are tasked with providing high-quality analytical results from complex biological samples in a high-throughput environment. The choice of sample preparation technique is important since this is the most time-consuming and labor-intensive process in bioanalysis. The importance of this step in bioanalysis steams from three major concerns – removing interferences from various biological samples matrices, concentrating the analytes of interest, and improving analytical method performance. Conventional sample preparation techniques such as dilution, filtration, liquid-liquid extraction and protein precipitation are now been consider as methods of the past. In bioanalysis, solid phase extraction is usually chosen as one of the best options available for sample preparation as it can provide substantial benefits including low matrix factor, high sample cleanliness, and concentration of low level analytes. Although solid-phase extraction is not novel sample preparation technique, during last decade we have witnessed its rapid development in bioanalysis. Improvements in solid-phase technique have been focused on development of innovative selective sorbens such as moleculary imprinted polymers, immunosorbent, nanoparticles and multi-mode sorbents. Furthermore, formats such as dispersive solid-phase extraction, disposable pipette extraction, 96-well plates, hybrid and twodimensional solid-phase extraction offer a variety of extraction processes and provide unique advantages of bioanalytical methods. On-line solid phase extraction utilizing column switching techniques is rapidly gaining acceptance in bioanalytical applications. The purpose of the present work was to illustrate the importance of sample preparation exemplified by solid-phase extraction for the bioanalytical method development of drugs (immunosuppressives and chemotherapeutic agents) and vitamins.

STC is precursor of aflatoxin and also the end product in biosynthesis of Aspergilli from the section Versicolores. Mechanism of STC toxicity is transformation by CYP monooxygenases into epoxide, which forms DNA-adducts leading to hepatotoxicity and carcinogenicity. STC-producing Aspergilli are frequently airborne in damp dwellings and could be expected in dust contributing to STC intake by inhalation. The purpose of the study was to employ HPLC/DAD/MS method for STC analysis in STC-producing Aspergilli extracts in order to estimate health risk based on their STC-producing capacity and frequency in dust taken in winter and summer of the year 2016 from flooded and unflooded houses in Croatia. STC analysis was performed by HPLC-DAD-ESI/MS/MS gradient method: Symmetry C18 4.6x150 mm, 3.5 μm column ; mobile phase (methanol/water), flow rate 1.0 ml/min ; DAD 254 nm ; positive ionization mode. Aspergilli (Versicolores) were of similar frequency in control and flooded village (40–100 %) but the concentrations in dust were more than 10 times higher in flooded houses (4.5 x 105 CFU/g). STC production was confirmed for 6/6 control village isolates (6–30.2 mg/mg) in winter and 3/5 isolates in summer period (25.1–42.2 mg/mg). Isolates from the flooded area showed similar STCproducing abilities (3/3 isolates, 2.4–22.1 mg/mg in winter ; 9/13 isolates, 1.9–39.9 mg/mg in summer). Significantly higher concentrations of dustborne Aspergilli STC-producers in flooded houses suggest increased health risk due to expected STC content in inhalable dust. This work has been fully supported by Croatian Scientific Foundation under the project MycotoxA (IP-09-2014- 5982).

Procijenjen je antioksidativni učinak dodataka prehrani namijenjenih ženama u menopauzi s fitoestrogenima.

A comparison of two extraction methods, liquid- liquid extraction andQuEChERS methodology, for the analysis of polyphenol content in olive oil was conducted.

In recent years, in most developed countries, the use of dietary supplements in general, and especially those intended for children is increasing. Despite the fact that most dietary supplements, especially those intended for children, can have side effects, legislation puts them in a group of foods, not drugs. Therefore there are not subject to such strict requirements of safety, quality and efficiency as medicines are. Because of higher availability, but also because of many other reasons, such as growing increase of self-care in general and growing concern of modern man for their own health, the opinion is prevailing that dietary supplements are safe. It is undisputed that the majority of food supplements for children can have very beneficial effects on their overall health. However, not enough attention is given to the fact that dietary supplements may have a positive effect only if these products are used for the right reason at the right time, in the right dose and in the right way. Do to the fact that children are a special group that are particularly vulnerable, one must keep in mind the issue of production and distribution practice, and the use of food supplements should be approached with caution. In order to avoid a number of potential risks that the use of dietary supplements in general especially those intended for children brings, dietary supplements should be subject to continuous scientific research, pharmaceutical expert supervision and appropriate legal controls. It is extremely important that the parents themselves acquire more knowledge about dietary supplements used by their children. Only if all above mentioned criteria are met, dietary supplements can achieve their optimum performance. The aim of this survey was to determine how much parents are familiar with dietary supplements intended for their children. In addition to evaluating the level of their knowledge on the composition, purpose and method of use of dietary supplements, in the present study we investigated the attitudes and opinions that parents generally have about dietary supplements. Based on the data of the survey conducted on a sample of parents (N = 415) it was found that parents perceive dietary supplements as safe. The research results unequivocally confirm the disturbingly low level of awareness of parents about dietary supplements for children. Such insight is ultimately a claim for an important advisory role of a pharmacist. In fact, the pharmacist should play a key role in advising parents to make an informed decision on the selection and manner of use of the food supplement for their child. Based on their knowledge, experience and expert assessment, pharmacists will decide whether there is a need for a certain dietary supplement, depending on the intended use and indications. If necessary they will recommend a different dietary supplement, explain in what cases to use it, and for how long, as well as how to use it. The pharmacist must raise parents’ awareness that dietary supplements contain active substance and that they should not be taken lightly and that the recommended daily dose should not be exceed. It is also necessary to point out that dietary supplements for children, especially those that contain plant extracts, may contain alcohol. The pharmacist, when dispensing medicines, should make a recommendation what dietary supplement may contribute to faster recovery, prevent or mitigate side effects and complications of pharmacotherapy. It is also important that the pharmacist emphasizes that certain dietary supplements should not be used with a certain drug because of possible interactions. In the end, it is necessary to point out that the pharmacist should play a key role in advising parents to make an informed decision on the selection of the dietary supplement for their child as well as the correct way of using it.

A new bioanalytical HPLC-DAD-MS/MS method was developed for determination of pirfenidon in serum samples.

In recent years, chromatography and mass spectrometry have gained a wide recognition as a sensitive, selective and fast techniques for the analysis of a wide range of food and dietary supplement (DS) products. An overview of our recently developed chromatographic and mass spectrometric methods used in food and DS analysis will be given. As counterfeiting of DS has become an important health and economic problem, a fast-screening DI-MS method for identification of various pharmacologically active ingredients was developed. Red fermented rice is used worldwide as an alternative therapy for hyperlipidemia. The recent discovery of a mycotoxin, citrinin, causes much controversy about the safety of these products. The LC/DAD/FLD/MSn method for determination of 5 monacolins and citrinin in a single run in food and DS have shown high deviations between labeled and found content. Despite recent efforts of regulatory authorities to improve the safety of DS, evaluation of ethanol is not harmonized. The sHSS-GC-FID method was applied for analysis of 93 samples. High amounts of ethanol were found in products for young children as well as in ˝alcohol-free˝ products. GC and HPLC methods for evaluation of the volatile compounds and food additives in blackberry wine were developed. Devastating results were obtained as several samples contained methanol above the permissible limits. Although olive growing is a traditional agricultural sector in Mediterranean countries, most of oil is obtained by small producers without production control. A low cost sHSS-GC-FID method may be used for evaluaton of volatile compounds, possible indicators of olive oil quality.

Po prvi put je razvijena MEKC metoda za analizu lijeka febuksostata i njegovih onečišćenja u gotovim ljekovitim oblicima.

Ispitane su dvije tehnike pripreme uzorka hrane za glodavce, ultrazvučna ekstrakcija i QuEChERS metodologija. U obrađenim uzorcima određen je pirfenidon primjenom HPLC-DAD/MS tehnike.

Crvena fermentirana riža popularni je prirodni hipolipemik. Kao aktivne sastavnice sadrži, između ostalog, 14 monakolina, s najvećim udjelom monakolina K, odnosno lovastatina. Primjenom četiri različite sofisticirane analitičke tehnike provedena je analiza dodataka prehrani s crvenom fermentiranom rižom u svrhu procjene njihove kvalitete.

Application of LC/DAD/MSn method for determination of 11 active ingredients in dietary supplements for (pre)monapausal symptoms

Razvoj nove brze i jednostavne kapilarnoelektroforetske metode za identifikaciju i određivanje febuksostata

Chlorella pripravak, registriran kao dodatak prehrani u RH, sve je popularniji farmaceutski pripravak zbog niza svojih, još uvijek nedovoljno istraženih, farmakoloških svojstava. Do sada je dokazano imunomodulatorno, detoksificirajuće, antitumorsko, protuupalno i revitalizirajuće djelovanje Chlorelle.

The aim of this research was to conduct a survey on general level of parent's awareness about DS for children, with special focus on parents' attitudes about DS' safety and effectiveness, and practice and habits on their use.

Prediction of bioavailability of lovastatin, simvastatin, pravastatin, fluvastatin, atorvastatin, and rosuvastatin by IAM-HPLC technique

Determination of ethanol and its seven major impurities in 93 liquid dietary supplements by static headspace capillary gas chromatography

Comparison of LC/DAD/MSn and Folin Ciocalteu methods for determination of phenolic contents in dietary supplement raw materials and dietary supplements for menopausal women

Simultaneous quantitation of methanol, ethanol and ethyl acetate in olive oil using headspace capillary gas chromatography with flame ionization detector was performed. Standard addition method was used for quantitation.

Određivanje udjela etanola i metanola u 21 dodatku prehrani s propolisom primjenom novorazvijene i validirane HSS-GC-FID metode

Dodaci prehrani namijenjeni djeci - znanje, navike i stavovi roditelja u primjeni ovih proizvoda te uloga ljekarnika

Food mineral content can vary significantly depending on the genetic and climate factors, farming procedures, soil composition, ripeness and many other factors. Furthermore, changes in mineral content usually occur as a result of applied technological procedures, e.g. removal of portion of raw material etc. The objective of this work was to classify the blackberry wine samples based on their mineral composition and the applied cultivation method of the starting raw material using chemometric analysis.

Determination of heavy metals by GFAAS technique in 93 liquid dietary supplements

Capillary electrophoresis is a fast and effective technique that can overcome various analytical challenges.

Optimizacija ekstrakcijskih uvjeta za analizu dodataka prehrani s fitoestrogenima

Rapid voltammetric method for determination of lovastatin in dietary supplements

HSS-GC-FID method for quality assessment of dietary supplements used in the pediatric patients

Ropinirole (ROP) is a novel nonergoline dopamine agonist indicated for the treatment of early and advanced Parkinson's disease and also for the treatment of primary restless legs syndrom. Due to noticeable shortage of analytical methods for ROP determination, there is a constant demand for developing reliable methods to evaluate the quality of its pharmaceutical formulations and to quantify drug in biological samples. Electroanalytical tecniques are particularly suitable for quantification of many drugs. Since the discovery, carbon nanotubes (CNTs) have been attracted enormous attention for the preparation of electrochemical sensors due to their unique structure and extraordinary electronic properties. A remarkable enhancement effect on the electrochemical response has been observed after dispersing CNTs in Nafion, a perflourosulfonated polymer. A simple and sensitive sensor was developed and electrochemical behaviour of ROP was investigated on the multi-walled carbon nanotubes/Nafion composite film modified glassy carbon electrode (MWCNTs- Nafion/GCE). Under optimized conditions, the response peak currents had linear relationship with drug concentration in the range of 1.0 x 10-7 – 1.0 x 10-5 M. A new electroanalytical method with good precision and accuracy was developed for direct quantification of ROP in tablets. The results were satisfactory in comparison with those obtained using high- performance liquid chromatographic method.

Development, validation and aplication of a new rapid capillary electrophoretic method for the analysis of mitotane's metabolite DDA in biological samples

Comparison of two new, HPLC-DAD and direct injection mass spectrometry, methods for the determination of mitatone's acetic acid metabolite in biological samples, urine, plasma and serum.

Development of a novel headspace - gas chromatographic method for determination of 8 volatile consitutents of cough syrups used in the pediatric patients.

U radu je dan pregled farmakološkog djelovanja crvene fermentirane riže te moguće nuspojave i interakcije.

Developlemnt of a new fast screening direct injection tandem mass spectrometry method for identification of allicin in garlic dietary supplements.

Razvijena je nova metoda izravnog injektiranja i masene spektrometrije za analizu dodataka prehrani sa zelenim čajem.

Development of a new HPLC-DAD-ESI-MS/MS method for simultaneous determination of 11 active phytoestrogens in dietary supplement materials and products used for menopausal symptoms.

Cilj rada bio je razviti i validirati novu HSS-GC-FID metodu za određivanje sadržaja etanola i njegovog najčešćeg onečišćenja, metanola, u sirupu za iskašljavanje za djecu. Provedena ispitivanja su pokazala da je predložena metoda selektivna, linearna, osjetljiva, precizna i točna. Metoda je uspješno primijenjena na komercijalno dostupnom sirupu za iskašljavanje za djecu.

Artičoka - eliksir s Mediterana, koji pomaže kod mnogih bolesti i stanja, uključujući i snižavanje razine kolesterola u krvi.

Development and validation of a new capillary electrophoretic method for determination of possible presence of active pharmaceutical ingredient lovastatin

Red fermented rice, also known as red yeast rice, Hongqu, Anka or red Koji, is the fermented product of rice on which red yeast (Monascus purpureus) has been grown. For a thousand of years it has been used in China to make rice wine, as a food preservative for maintaining the color and taste of fish or meat and as a traditional medicine for digestive and vascular function. A complete and detailed description of its manufacture and medicinal properties are found in the ancient Chinese pharmacopoeia, published during the Ming Dynasty (1368–1644 a.d.). Over the past decade, there has been increased scientific interest in red yeast rice, as an alternative therapy for hyper cholesterolemia. Many studies have demonstrated that red yeast rice may be especially useful for treating patients who refuse to take statin drugs because of philosophical reasons or patients who are unable to tolerate statin therapy due to statin-associated myalgias. The major components found in red yeast rice, known as monacolins (polyketides), are reported to exhibit a cholesterol lowering action by inhibiting the 3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase. Still, it is believed that the hypolipidemic effect of red yeast rice cannot be accounted for only by the monacolins, but by a synergy of all other components present in red yeast rice: plant sterols, isoflavones and isoflavone glycosides, selenium and zinc. The most important toxic component in red fermented rice is citrinin, a mycotoxin produced by red yeast (Monascus purpureus). It has been known to cause kidney and liver damage in humans. Therefore, Japan has issued an advisory limit of 200 ppb while the European Union has a recommended limit of 100 ppb. The aim of our work was to develop a new LC/MS/MS method for identification of active components, monacolin K (lovastatin) and monacolin K acid and toxic component, citrinin, present in red yeast rice capsules.

Development, optimization and validation of a new capillary electrophoretic method for analysis of lovastatin and citrinin in red rice dietary supplements

A presentation of advance analytical techniques for identification and quantification of active compounds and impurities present in dietary supplements is given. High performance liquid chromatography (HPLC) coupled to 3 different detectors, diode array (DAD), fluorescence (FLD) and electro spray ionization ion trap analyzer (ESI-MSn) is presented. Capillary electrophoresis (CE) is also described, since a micellar electrokinetic method (MEKC)is employed for determination of active compounds as well as toxic by-products. Headspace-gas chromatography-flame ionization detector (HSS-GC-FID) method is presented for determination of volatile compounds in diverse dietary supplements.

Development and validation of a new HPLC/DAD/FLD/MSn method for identification and quantification of lovastatin in both lactone and hydroxy acid form, as well as nefrotoxic citrinin, in red yeast rice food and dietary supplements

Adrenocortical carcinoma (ACC) is a rare malignancy with an incompletely understood pathogenesis and a poor prognosis. The adrenalytic activity of mitotane has made it most important single drug in the treatment of ACC. Unfortunately, the exact mechanism of mitotane action is still unknown. It is believed that mitotane belongs to the class of drugs that require metabolic transformation by cytochrome P450 for therapeutic action ; therefore determination plasma levels of not only mitotane but also its metabolites would help in carrying out the treatment. The objective of this work was to develop and validate SPE-HPLC method for simultaneously determination of mitotane and its metabolites in different biological fluids. The sample preparation consisted of a solid-phase extraction on a Discovery DSC-18 cartridge, while analysis of extracts was performed on a Symmetry C18 column. Usefulness of the proposed method has been confirmed by analysis of plasma, red cell and urine samples from patient chronically treated with 1.5 g of mitotane. The patient involved in this study had high plasma concentration of mitotane and none of investigated metabolites was found. In order to investigate weather the polymorphism of CYP2C9 and CYP2C19 enzymes could be related to the metabolism of mitotane RT-PCR analysis was performed.

Artichoke (Cynara scolymus), belonging to the family of Asteraceae, is an herbaceous perennial crop, widely cultivated in the Mediterranean area. The heads of the artichoke are edible and used worldwide, while the leaves are an herbal medicine recognized far a long time far their beneficial and therapeutic effects, including induction of choleresis, LDL oxidation and significant antioxidant, antifungal, antibacterial as well as strong hepatoprotective activity. Artichoke contains very little fat and high levels of minerals, vitamins, fibre, inuline and polyphenols. The most abundant phenolic compounds reported in artichoke leaf are flavonoides such as apigenin and luteolin (both glycosides and rutinosides), as well as phenolic acids, particularly derivatives of mono- and di-caffeoylquinic acid. Although all polyphenols are included in cholesterol lowering effect of artichoke leaf, the most responsible one is cynarin, derivative of dicaffeoylquinic acid. As dietary supplements have an important position in health care systems worldwide, their current assessment and quality control are a major bottleneck. Over the last years, major steps were taken to improve the quality of the dietary supplements and also to develop analytical methods ensuring their quality. High performance liquid chromatography has become the most popular analytical technique far analyzing dietary supplements. The main advantages of the technique are high resolution, selectivity, sensitivity and possibility to couple the technique to different detectors. Therefore, the aim of the present work was to develop a new HPLC! DADIMS/MS method far identification of cynarin present in artichoke leaf extract tablets.

Predviđanje farmakokinetike lovastatina, simvastatina, pravastatina, fluvastatina, atorvastatina i rosuvastatina primjenom tekućinske kromatografije visoke djelotvornosti i molekulskog modeliranja