Diverse elements in herbal tea products consumed in serbia using inductively coupled plasma mass spectrometry

Nine elements (Fe, Cu, Mn, Zn, As, Cd, Sn, Hg, and Pb) were determined in 8 teas and 25 herbal teas widely consumed in Serbia for medical purposes. Green, black, peppermint, chamomile, cranberry, sage, rosehip, uva, senna, marigold, and fennel teas were investigated. Microwave-assisted acid digestion was used for all of the samples, and the element contents were determined by inductively coupled plasma mass spectrometry. From all of the determined microelements, the highest content was that of Mn, 2912.8 and 2541.8 mg/kg of dry matter in the black and green tea, respectively. The contents of toxic elements (As, Cd, and Pb) were below the maximum permissible levels, except for one brand of peppermint tea in which the level of Cd was 8.61 mg/kg, much higher than the allowed 0.3 mg/kg

Određivanje sadržaja metala u mešavinama biljnih čajeva sa tržišta u Beogradu primenom induktivno spregnute plazme sa masenom spektrometrijom

The metal contents of Fe, Cu, Mn, Zn, As, Cd, Sn, Hg and Pb in the five herbal tea mixtures containing a variety of different plants were determined. Microwave-assisted acid digestion was used for all of the samples, and the element contents were determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). A matched calibration curve method was used for the quantification of the analytes. For accuracy assay, SRM 2977, NIST, Mussel Tissue (Organic Contaminants and Trace Elements) was used. The obtained results agreed with the certified values. The concentration of all elements varied among examined herbal tea mixtures and are in the expected intervals. The contents of all investigated toxic elements were below the maximum permissible levels.U ovom radu određen je sadržaj metala u pet izabranih mešavina biljnih čajeva. Devet elemenata: Fe, Cu, Mn, Zn, As, Cd, Sn, Hg i Pb su analizirani metodom induktivno spregnute plazme sa masenom spektrometrijom (ICP-MS). Uzorci su pripremani mikrotalasnom digestijom, sadržaj metala određen je primenom eksterne kalibracije, a tačnost metode proverena je pomoću standardnog referentnog materijala (SRM 2977, NIST) i internog standarda. Dobijeni rezultati su u dobroj saglasnosti sa sertifikovanim vrednostima. U zavisnosti od ispitivane mešavine, koncentracije analiziranih elemenata su različite i nalaze se u očekivanim intervalima. Koncentracije svih teških metala su ispod dozvoljene granice

Uloga biomarkera i surogatnih parametara u pretkliničkim i kliničkim ispitivanjima lekova

Biomarkeri imaju široku primenu u modernoj medicini i biologiji. Oni su promenili način dijagnostikovanja i klasifikacije bolesti, praćenja efekata terapije, određivanja toksičnosti, a imaju i sve veću primenu u razvoju novih lekova. Karakteristike biomarkera određuju i njihovu primenu. Biomarkeri koji imaju malu moć predviđanja korisnosti tretmana koriste se u ranim fazama razvoja lekova za preliminarni skrining. Biomarkeri velike prediktivne moći mogu biti upotrebljeni kao surogatni parametri u proceni efikasnosti i bezbednosti tretmana. Surogatni parametri validirani u kliničkim istraživanjima i prihvaćeni od strane regulatornih agencija mogu biti korišćeni i za registraciju lekova, naročito za ubrzanu registraciju antiinfektivnih lekova i hemoterapeutika. Međutim, za registraciju antikancerskih lekova regulatorne agencije insistiraju na neophodnosti prospektivnih postmarketinških studija da bi se dokazalo postojanje korelacije surogatnih parametara sa kliničkom koristi od primenjenog tretmana.

Hemiluminiscencija - teorijski princip, reakcije i primena u kliničkoj laboratorijskoj praksi i istraživanjima

This article reviews the fundamental and applied aspects of chemiluminescence and its applications in both routine clinical analysis and in the diverse applications in clinical research. Chemiluminiscence reactions are basic of luminometric assays, induce ultra sensitive detection limits (attomole-zeptomole), rapid assays, and a broad range of analytical applications. In the routine clinical laboratory, chemiluminescence is now commonly used for immunoassay and DNA probe assays, in the form of a chemiluminescent labels (acridinium ester, acridinium sulfonamide) and detection reactions for peroxidase and alkaline phosphatase enzyme labels (luminol and adamantyl 1,2-dioxetane-based reactions, respectively). Chemiluminescent immunoassay test kits and automated immunoassay analyzers have been developed. There are broad range of chemiluminescent immunoassay tests which are routinely used for the measurement of the biochemistry, immunology, toxicology, virology, and endocrinology analytes in the assessment of thyroid function, fertility, myocardial damage, anemia, therapeutic drug levels, and diagnosing and monitoring drug abuse, cancer and infectious diseases (e.g. hepatitis). In clinical research, the sensitivity, dynamic range and diversity of chemiluminescent assays has led to a vast range of applications, notably in protein and nucleic acid blotting, microarray-based assays, monitoring reactive oxygen species, and as detection reactions for substances separated by HPLC and capillary electrophoresis. Nowadays, in clinical research, chemiluminescent detection techniques are used to measure enzymes expressed by reporter genes, cellular luminescence, blotted proteins (Western blotting) and nucleic acids (Northern and Southern blotting).U ovom radu, dato je teorijsko objašnjenje nastanka hemiluminiscencije i prikazane su najznačajnije hemiluminiscentne i bioluminiscentne rekcije. Na bazi hemiluminiscencije razvijena je moćna, visoko osetljiva analitička tehnika - luminometrija, sa detekcionionim limitom do atomola (10-18) i čak zeptomola (10-21), koja je našla široku primenu u imunohemijskim određivanjima i DNK analizama. U tu svrhu, ispitivana jedinjenja se vezuju za hemiluminiscentne obeleživače (akridinijum estar, akridinijum sulfonamid), ili se obeležavaju enzimima (peroksidazom ili alkalnom fosfatazom), koji pojačavaju signal hemiluminiscentnih reakcija. U rutinskoj praksi, primenjuje se veliki broj hemiluminiscentnih imuno-testova za merenje biohemijskih, imunoloških, toksikoloških, virusoloških i endokrinoloških analita u cilju ispitivanja funkcije tiroideje, fertiliteta, oštećenja miokarda, anemije, praćenja koncentracije leka, dijagnoze i praćenja zloupotrebe lekova, otkrivanja i praćenja terapije kancera, kao i infektivnih bolesti (npr. hepatitis). U kliničkim istraživanjima, zahvaljujući osetljivosti, brzini i raznolikosti izvođenja, došlo je do široke primene hemiluminiscencije, posebno u metodama ispitivanja proteina i nukleinskih kiselina pomoću blotting metoda (Western, Northern i Southern blotting), microarray matoda, praćenja reaktivnih kiseoničnih radikala, kao i u reakcijama detekcije supstanci, koje su prethodno razdvojene tečnom hromatografijom i kapilarnom elektroforezom. Danas se tehnike hemiluminiscentne detekcije koriste i za merenje aktivnosti enzima za čiju sintezu su odgovorni određeni geni (reporters genes)

Direct Spectrophotometric Determination of Hesperidin in Pharmaceutical Preparations

A simple, rapid and reliable direct spectrophotometric method for the determination of hesperidin is proposed and validated. The influence of wavelength, solvent, the ionic strength, pH and temperature on hesperidin determination were investigated. Under the optimum conditions, lambda = 283 nm, 60% methanol as the solvent, ionic strength, I = 2.5 x 10(-5) mol L-1, pH = 6.4 and T = 37.0 degrees C, the Beer's law is obeyed in the concentration range 1.83-24.5 mu g mL(-1). The molar absorptivity and Sandells sensitivity were found to be 1.8 x 10(4) L mol(-1) cm(-1) and 0.03 mu g cm(-2), respectively. The sensitivity of the proposed method was 0.9 mu g mL(-1) (as limit of detection) and 3.2 mu g mL(-1) (as limit of quantification). Applicability of the proposed method to the direct determination of total flavonoids as hesperidin equivalents in pharmaceutical formulation (Vitamin C with citrus bioflavonoids & Rose Hips) was demonstrated. Although the presence of ascorbic acid may cause problem in identification and measurements, hesperidin has been determined successfully

Imunonefelometrija i imunoturbidimetrija - teorijski principi, instrumenti i primena

Nephelometry and turbidimetry are methods based on the phenomenon whereby light, passing through a medium with dispersed particles is attenuated in intensity by scattering. The intensity of the scattered light is measured at right angle (usually, but not necessarily) to the incident light beam (nephelometry) or at a forward angle (turbidimetry). Based on nephelometry and turbidimetry, immunonephelometric and immunoturbidimetric assays for the measurement of proteins have developed and expanded rapidly in recent years, progressively replacing the time-honored gel precipitation techniques. In this study, the theoretical background of light scattering theory, instrumental systems for nephelometry and turbidimetry, the nature and kinetics of the antibody-antigen reaction in fluid, and the application of immunonephelometric and immunoturbidimetric assays for specific proteins in the clinical laboratory are described.Nefelometrija i turbidimetrija su metode koje sa zasnivaju na rasipanju svetlosti: pri prolasku kroz disperzionu sredinu, svetlost se rasipa na česticama disperzione faze. Intenzitet rasute svetlosti može se meriti pod nekim uglom (uobičajeno, ali ne i obavezno, pod pravim uglom), što predstavlja nefelometriju ili u pravcu upadne svetlosti, što predstavlja turbidimetriju. Primenom nefelometrije i turbidimetrije u imunologiji, razvile su se imunonefelometrija i imunoturbidimetrija, kao savremene tehnike za određivanje proteina i peptida, koje su zamenile klasične, dugotrajne, precipitacione tehnike u gelu. U ovom radu objašnjene su teorijske osnove rasipanja svetlosti, prikazane su sheme i delovi instrumenata nefelometra i turbidimetra i opisane su imunonefelometrija i imunoturbidimetrija koje su u širokoj upotrebi u savremenim kliničkim laboratorijama

Radioaktivni izotopi (radionuklidi) i radiofarmaceutici

The radioisotopes (radionuclides) and radiopharmaceuticals which have been predominantly used as diagnostic agents are presented in this work. In nuclear medicine, most pharmaceuticals are labeled with technetium-99m because of its almost ideal physical and nuclear properties. In this work the review of officinal dosages forms of radiopharmaceuticals in Pharmacopoeia Yugoslavia 2000 is given.U ovom radu dat je prikaz radioaktivnih izotopa (radionuklida) i radiofarmaceutika koji se danas koriste prvenstveno u dijagnostičke svrhe. U nuklearnoj medicini najviše se koriste radiofarmaceutici obeleženi tehnecijumom-99m koji ima skoro idealne fizičke i radijacione osobine. U radu je dat pregled doziranih oblika radiofarmaceutika oficinalnih po Jugoslovenskoj Farmakopeji 2000

Primena metode tečne hromatografije u ispitivanju stabilnosti farmaceutskih supstanci i farmaceutskih preparata

The stability - indicating method is an analytical procedure used to detect a decrease in the amount of an active pharmaceutical ingredient present due to degradation. According to FDA guidelines, stability - indicating method is defined as a validated analytical procedure that accurately and precisely measures active ingredients free from potential interferences like degradation products, process impurities, excipient or other potential impurities. During stability studies, liquid chromatography is used routinely to separate and determine the analyses of interest. For implementing the stability - indicating method, several steps are needed. An active pharmaceutical substance is firstly subjected to the forced degradation studies followed with the investigations of its interactions with the excipient from the pharmaceutical preparation, the optimization of chromatographic conditions and the method validation.Praćenje stabilnosti nekog leka je postupak kojim se određenom analitičkom metodom precizno mogu identifikovati i odrediti komponente nastale kao rezultat degradacije aktivne supstance kako u farmaceutskoj supstanci tako i u farmaceutskom proizvodu. Prema smernicama Agencije za hranu i lekove (eng. Food and drug administration, FDA), metoda za praćenje stabilnosti se definiše kao metoda farmaceutske analize kojom se precizno može kvantifikovati aktivna komponenta, u prisustvu degradacionih proizvoda, nečistoća koje potiču iz procesa sinteze, ekscipijenasa ili drugih potencijalnih nečistoća. U te svrhe, danas se najčešće primenjuje metoda tečne hromatografije pod visokim pritiskom (eng. High pressure liquid chromatography - HPLC, u daljem tekstu tečna hromatografija). Razvoj metode za praćenje stabilnosti podrazumeva nekoliko faza. U prvoj fazi se izvode studije forsirane degradacije sa čistom aktivnom supstancom, nakon toga se vrši ispitivanje interakcija aktivne supstance sa komponentama ekscipiensa farmaceutskog preparata, optimizacija hromatografskih uslova i validacija metode

Ispitivanje nekih polioksalometalata Keginovog tipa kao potencijalnih antitumorskih agenasa

The antitumour action of three polyoxometallate compounds of Keggin's type: 12-molibdophosphoric acid (MoPA), 12-tungstophosphoric acid (WPA) and Mg salt of WPA (MgHWPA) was studied in vitro. For human cervix carcinoma (HeLa) cells survival, as well as for nonstimulated and stimulated peripheral blood mononuclear cells (PBMC), MTT test was applied and IC50 values of POMs were determinated. Index selectivity for WPA and MgHWPA are 1.9 and 1.8, calculated for nonstimulated, as well as 2.5 and 2.0, calculated for stimulated PBMS. Combination of studied POMs do not contribute to their lower IC50 values. Apoptosis detection implies mild cytotoxic effect of WPA and more cytostatical effect of MgHWPA. Combination of each of the studied POMs with caffeine decreases HeLa survival in dose dependent way. None of the studied POMs in the used concentrations (up to 100 mmol/L) damages blood cells and/or decreases their number.Ispitivano je in vitro antitumorsko dejstvo tri jedinjenja iz grupe polioksometalata (POM-a) Keginovog tipa: 12-fosformolibdenska kiselina (MoPA), 12-fosforvolframova kiselina (WPA) i Mg so 12-fosforvolframove kiseline (MgHWPA). Primenom MTT testa na ćelije karcinoma cerviksa (HeLa ćelije), kao i na nestimulisane i stimulisane mononuklearne ćelije iz periferne krvi (PBMC), određene su IC50 vrednosti ispitivanih POM-a. Indeksi selektivnosti za WPA i MgHWPA su 1,9 i 1,8 računati za nestimulisane, odnosno 2,5 i 2,0 za stimulisane PBMC. Kombinacijom ispitivanih POMa ne postiže se smanjenje njihovih IC50 vrednosti. Detekcijom apoptoze utvrđeno je da WPA pokazuje blagi citotoksični efekat, dok MgHWPA ima blagi citotostatski efekat. U kombinaciji sa kofeinom, POM jedinjenja još više smanjuju preživljavanje HeLa ćelija. U ispitivanim koncentracijama (do 100 mmol/L), nijedno od POM jedinjenja ne utiče na broj i izgled krvnih ćelija pune krvi zdravih davalaca