In testing the pre-sale procedure the marketing of drugs and their control in the last ten years, high performance liquid chromatography replaced numerous spectroscopic methods and gas chromatography in the quantitative and qualitative analysis. In the first period of HPLC application it was thought that it would become a complementary method of gas chromatography, however, today it has nearly completely replaced gas chromatography in pharmaceutical analysis. The application of the liquid mobile phase with the possibility of transformation of mobilized polarity during chromatography and all other modifications of mobile phase depending upon the characteristics of substance which are being tested, is a great advantage in the process of separation in comparison to other methods. The greater choice of stationary phase is the next factor which enables realization of good separation. The separation line is connected to specific and sensitive detector systems, spectrafluorimeter, diode detector, electrochemical detector as other hyphernated systems HPLC-MS and HPLC-NMR, are the basic elements on which is based such wide and effective application of the HPLC method. The purpose high performance liquid chromatography (HPLC) analysis of any drugs is to confirm the identity of a drug and provide quantitative results and also to monitor the progress of the therapy of a disease.1) Measuring presented on the Fig. 1. is chromatogram obtained for the plasma of depressed patients 12 h before oral administration of dexamethasone. It may also be used to further our understanding of the normal and disease process in the human body trough biomedical and therapeutically research during investigation before of the drugs registration. The analyses of drugs and metabolites in biological fluids, particularly plasma, serum or urine is one of the most demanding but one of the most common uses of high performance of liquid chromatography. Blood, plasma or serum contains numerous endogenous compounds often present in concentrations much greater than those of analyte. Analiyte concentrations are often low, and in the case of drugs, the endogenous compounds are sometimes structurally very similar to the drug to be measured. The binding of drugs to the plasma protein also may occur which decreases the amount of free compound that is measured. To undertake the analyses of drugs and metabolites in body fluids the analyst is facet with several problems. The first problem is due to the complex nature of the body fluid, the drugs must be isolated by an extraction technique, which ideally should provide a relatively clean extract, and the separation system must be capable of resolving the drugs of interest from co extractives. All mentioned when we are using high performance liquid chromatography require good selections of detectors, good stationary phase, eluents and adequate program during separation. UV/VIS detector is the most versatile detector used in high performance liquid chromatography it is not always ideal since it is lack of specificity means high resolution of the analyte that may be required. UV detection is preferred since it offers excellent linearity and rapid quantitative analyses can be performed against a single standard of the drug being determined. Diode array and rapid scanning detector are useful for peak identification and monitoring peak purity but they are somewhat less sensitive then single wavelength detectors. In liquid chromatography some components may have a poor UV chromophores if UV detection is being used or be completely retained on the liquid chromatography column. Fluorescence and electrochemical detector are not only considerably more sensitive towed appropriate analytes but also more selective than UV detectors for many compounds. If at all possible fluorescence detectors are sensitive, stable, selective and easy to operate. It is selectivity shows itself in the lack of frontal components observed in plasma extract whereas electrochemical detection is nearly always associated with a major frontal peak than tails considerably. To date, the most sensitive method has been the reductive electrochemical detection and giving the excellent results in the investigation on some classes of drugs. Several high performance liquid chromatography oxidative electrochemical methods have been developed for the analyses of drugs and metabolites in body fluids. Mass spectrometer as specific detector with all variation of ionisation and interface (thermo spray, moving belt etc. ) or liquid chromatography-tandem mass spectrometry2,3,4,5). NMR as selective and specific detector in high performance liquid chromatography today is also in used. The development of a non-aqueous eluent for ion-exchange separation on silica has provided an excellent system which, when used in conjugation with an electrochemical detector, permits the analyses of an extensive range of especially basic drugs and metabolites. New packing materials such as polymeric, base deactivated silica's, pyrolysed carbon and the internal surface packing should offer the improved stability and higher efficiencies for certain classes of the compounds such as basic drugs. Microbore columns should become more accepted since they offer not only improved sensitivity but also a lower solvent consumption and consequently the reduced needs to dispose of noxious solvents. Many analyses of basic drugs are still performed by the same method of the ion-exchange chromatography on unmodified silica columns with an eluent buffered to about pH 9. Neutral or weakly acidic drugs for instance barbiturates can be chromatographed on a reversed phase system whilst acidic drugs for example paracetamol, cannabis are separated either by ion suppression or ion-pair chromatography on a reversed-phase packing material. In micelar liquid chromatography micelar mobile phases in reversed-phase instead of conventional hydro organic mobile phase is used. In micelar liquid chromatography complex electrostatic hydrophobic and steric interactions exist between the solute and both stationary and mobile phases. These enable the effective separation of samples of different nature. The main advantages of the use of a micelar solution in reversed-phase liquid chromatography are the solvent and the lower cost and toxicity, the biodegradability of the solvent and the easy dissolution of analytical samples, that enables the determination of drugs in physiological fluids without the need for previous separation of the proteins present in the samples. Using tetrabutylammonium phosphate as a competing base in the investigation of sulphonamides and heptanes sulfonate as ion pairing reagent. Ion pairing reagent is term used to describe enhanced retention as the result of the addition to the mobile phase of a large ion opposite charge to the molecular ions to be separated. For molecular cations alkyl sulphates or sulfonates are generally utilised.

In this paper we present introduction and development of some new analytical methods for identification of anabolic steroids, their metabolites and certain hormones, especially determination of exogenous testosterone by means of gas chromatography-mass spectrometry. Identification of central nervous stimulants and corticosteroides has been performed by high performance liquid chromatography. In desire to achieve better results, to increase strength and endurance, to sharpen reflexes and to reduce stress and anxiety athletes as well as other people use different pharmacological substances, hormones or even illicit drugs. Use of these substances without medical supervision can lead to adverse effects to one's health or even cause a death. At the same time, use of such substances means a kind of cheat that could not be accepted. This is why International Olympic Committee started at 1968 with official doping control that is permanently carried out and continuously increasing number of banned substances. Doping control demands for discover and development of new sensitive and specific methods for detection of banned substances and their metabolites in urine and blood.

Polycyclic aromatic hydrocarbons are common environmental pollutants that reach atmosphere in the form of aerosol adsorbed on soot, ash and dust. Having in mind its carcinogenic and mutagenic effects most countries have regulations concerning their estimation in environmental samples. In this work we have investigated extraction efficiency of several polycyclic aromatic hydrocarbons from flying particles collected on glass fiber filters. Efficiency of extraction of different duration in Soxhlet apparatus, ultrasonic bath and boiling toluene under reflux were compared. It has been established that compounds having two or three condensed rings are lost during evaporation of toluene that was used as a solvent. For compounds having five or more condensed rings extraction in ultrasonic bath and boiling toluene using magnetic stirrer and reflux are the most efficient.

Content of atropine in eye drops of atropine sulfate were determined colorimetrically and spectrophotometricaly using methods of ion pairs with bromtimolblue. The described method is more convenient for routine analysis then non aqueous titration described in various Pharmacopeas.

Metabolite of 17-methyl-17-hydroxy-2-(hydroxymethylen)-androstan-3-one (oxymetholane) in urine after a single oral administration was monitored by gas chromatography+mass spectrometry. During the investigation prepared TMS-ethers and TMS-enol-ethers of conjugated steroid fraction two new metabolites of oxymetholone have been identified: tetrahydrooxymetholone and tetrahydro-6-hydroxy-oxymetholone.

The erythrocyte content of protoporphyrin IX was measured in a group of 191 battery plant workers. According to the results of biological monitoring the selected workers had increased occupational exposure to lead. Measurements were done with a commercial haematofluorometer Buchler ZF which was calibrated to the average haematocrit value of 0.42. The values measured were then corrected to individual haematocrit values. Haematocrit was determined in the standard manner and the individual values ranged from 0.38 to 0.51. Test results showed a major difference in protoporphyrin IX concentrations directly determined with a haematofluorometer and the ones calculated by correcting to the individual haematocrit.

Mass spectrometry has been applied for the structural study of some new unsymmetrically 3,5-disubstituted 4-isoxazolecarboxylic acids prepared by a modification of the general procedure of Quilico and Fusco. The new glucoside, 3-[2-(β-D-glucopyranosiloxy)-5-chlorophenyl]-5-methyl-4-isoxazolecarboxylic acid (1) and 3-(2-hydroxy-3,5-dichlrophenyl)-5-methyl-4-isoxazolecarboxylic acid (2) have been prepared starting from the glucoside helicin, 2-(β-D-glucopyranosiloxy) benzaldehyde or the corresponding aglucon, the salicylaldehyde, respectively. Fragmentation patterns of 2 and its analogue 3-(2-hydroxy-5-chlorophenyl)-5-methyl-4-isoxazolecarboxylic acid (3), obtained by the cleavage of the glycosidic linkage of 1 are discussed. The principal fragmentation routes of these compounds are formulated to occur via azirine intermediates.

Piperidine heterocycles are present in the structure of many alkaloids, for example coniine in the structures of lobelia, cocaine alkaloids and sedum alkaloids, Sedum alkaloids are 2,6-disubstituted derivatives of piperidine or N-methylpiperidine. Extracts obtained from Sedum acre L. were investigated for the presence of alkaloids by gas chromatography/mass spectrometry. Identification has been carried out on the basis of retention time, molecular ion mass and characteristic fragmentation. Investigated extracts contained unknown alkaloids which belong to the piperidine group of sedum alkaloids. Mass spectral fragmentation patterns and a proposed structure for the unknown alkaloids are discussed.

The content of some polycyclic aromatic hydrocarbons in extracts of particulate matter collected in the city of Zenica in December 1987 was analysed. In addition to the presence of proven carcinogens like benzo(a)pyrene, benzo(a)anthracene, chryzene and dibenzo(a,h)anthracene, the contents of naphthalene, fluorene, fenanthrene, anthracene, fluoranthene and pyrene were also determined. Those substances were rightly assumed to be precursors of genotoxic products in reactions with atmospheric nitrogen oxides. The determined average concentration of benzo(a)pyrene was higher than those found in other places in Yugoslavia where similar studies were conducted. At the same time, the measured benzo(a)pyrene concentration exceeded the guidelines for inhabited places according to the standards of the Federal Republic Germany and the Netherlands. The observed high variations in naphthalene concentration of as much as two orders of magnitude in two days were likely due to unsolved technological problems.