BACKGROUND: ROBINIA PSEUDOACACIA L., (BLACK LOCUST), IS DISTRIBUTED WORLDWIDE IN TEMPERATE CLIMATES AND WIDELY FOUND IN IRAN [1]. THERE ARE MANY FLAVONOIDS PRESENT IN ROBINIA IN LOW CONCENTRATIONS, WHICH REMAIN UNIDENTIFIED [2]...

BACKGROUND: PHENYLEPHRINE HYDROCHLORIDE IS A SYMPATHOMIMETIC DRUG. IT CAN BE USED AS A NASAL DECONGESTANT. THE DRUGS IN BIOLOGICAL SAMPLES ARE TOO DILUTED AND THE MATRIX IN THIS MEDIUM IS TOO COMPLEX. THEREFORE, A SAMPLE PREPARATION STEP IS NECESSARY TO EXTRACT TRACE AMOUNT OF THESE DRUGS FROM THE BIOLOGICAL MEDIUM, BRING THE ANALYTES TO A SUITABLE CONCENTRATION LEVEL, AND REMOVE THEM FROM INTERFERING COMPONENTS IN THE MATRIX [1]. DISPERSIVE LIQUID-LIQUID MICROEXTRACTION (DLLME) WAS INTRODUCED BY REZAEE IN 2006. IN THIS METHOD EXTRACTION EQUILIBRIUM IS QUICKLY ACHIEVED, DUE TO THE EXTENSIVE SURFACE CONTACT BETWEEN THE DROPLETS OF THE EXTRACTION SOLVENT AND THE AQUEOUS SAMPLE. THEREFORE, THE EXTRACTION TIME IS VERY SHORT. DLLME HAS POTENTIAL ADVANTAGES WHICH INCLUDE THE SIMULTANEOUS EXTRACTION AND PRECONCENTRATION OF TARGET ANALYTE, COST EFFECTIVENESS, SIMPLICITY AND RAPIDITY OF OPERATION, LOW CONSUMPTION OF SOLVENT AND REAGENT, HIGH ENRICHMENT FACTOR AND ENVIRONMENTAL BENIGNITY [2].METHODS: IN THIS WORK, 5 ML OF STANDARD SOLUTION CONTAINING 50 MG L-1 (PH 5.0) OF PHENYLEPHRINE AND 0.6 MMOL L-1 OF SDS WAS POURED IN TO A CONICAL TUBE. THEN 50 ML OF 1-OCTANOL (EXTRACTION SOLVENT) WAS RAPIDLY INJECTED IN TO THE AQUEOUS SAMPLE BY SYRINGE. THE TUBE WAS IMMERSED IN TO AN ULTRASONIC BATH FOR 8 MIN AT 25OC. A CLOUDY SOLUTION WAS FORMED IN THE TEST TUBE, IN FACT PHENYLEPHRINE IN AQUEOUSE SAMPLE WAS EXTRACTED IN TO THE FINE DROPLETS OF 1-OCTANOL. THE MIXTURE WAS CENTRIFUGED AND DISPERSED FINE DROPLETS OF THE EXTRACTION PHASE WERE COLLECTED ON THE TOP OF THE TUBE, THEN 10 ML OF COLLECTED PHASE WAS DIRECTLY INJECTED IN TO HPLC FOR ANALYSIS. EXPERIMENTAL CONDITIONS, SUCH AS THE TYPE AND VOLUME OF EXTRACTION SOLVENT, THE CONCENTRATION OF SURFACTANT, EXTRACTION TIME, TYPE AND VOLUME OF BUFFER AND PH WERE OPTIMIZED.RESULTS: UNDER THE OPTIMAL CONDITIONS, LINEARITY RANG WAS OBTAINED FROM 0.5-50 NG/ML (R=0.9997), DETECTION OF LIMIT WAS 0.2 NG/ML AND RSD (N=8) FOR 5 AND 35 NG/ML OF PHENYLEPHRINE WAS OBTAINED 4% AND 2.5% RESPECTIVELY.CONCLUSION: THE EXPERIMENTAL RESULTS REVEALED THAT THIS METHOD PROVIDES HIGH RECOVERY AND PRECONCENTRATION FACTOR WITHIN A SHORT TIME AND GOOD LINEARITY OVER THE INVESTIGATED CONCENTRATION RANGE. THEREFORE, DLLME IS USEFUL FOR DETERMINATION PHENYLEPHRINE IN BIOLOGICAL AND PHARMACEUTICAL SAMPLE.

A DISPERSIVE LIQUID-LIQUID MICROEXTRACTION (DLLME) METHOD WAS DEVELOPED FOR THE DETERMINATION OF ALUMINIUM IONS. DLLME HAS BECOME A VERY POPULAR ENVIRONMENTALLY BENIGN SAMPLE-PREPARATION TECHNIQUE, BECAUSE IT IS FAST, IN EXPENSIVE EASY TO OPERATE WITH A HIGH ENRICHMENT FACTOR AND CONSUMES LOW VOLUME OF ORGANIC SOLVENT [1]. THE METHOD WAS BASED ON THE COMPLEX AL (III) WITH PYROCATECHOL VIOLET AND CETYLTRIMETHYL AMMONIUM BROMIDE (CTAB) AS AN ION PAIREAGENT [2]. AN APPROPRIATE MIXTURE OF METHANOL (AS DISPERSIVE SOLVENT) AND CHLOROFORM (AS EXTRACTION SOLVENT) WAS INJECTED RAPIDLY INTO THE AQUEOUS SAMPLE AS A RESULT CLOUDY MIXTURE WAS FORMED. AFTER THIS STAGE, CENTRIFUGATION WAS USED TO SEDIMENT THESE DROPLETS TO THE BOTTOM OF THE CONICAL TUBE. THE MAIN FACTORS AFFECTING IN DLLME OF AL (III), SUCH AS TYPE AND VOLUME OF EXTRACTANT AND DISPERSER SOLVENT, CONCENTRATION OF CHELATING REAGENT, PH OF SAMPLE SOLUTION, SALT EFFECT, EXTRACTION AND REACTION AND CENTRIFUGATION TIME, CENTRIFUGATION RATE WERE STUDIED [3].UNDER THE OPTIMIZED CONDITIONS, THE PROPOSED METHOD PROVIDED A GOOD LINEARITY, LOW LIMITS OF DETECTION AND GOOD REPEATABILITY OF THE EXTRACTIONS [4]. FINALLY, THE PROPOSED DISPERSIVE LIQUID LIQUID MICRO EXTRACTION METHOD WAS SUCCESSFULLY APPLIED FOR THE DETERMINATION OF ALUMINIUM IN VARIOUS NATURAL WATER, MEDICINE AND BLOOD SAMPLES [5].

THE PRESENCE OF SMALL AMOUNTS OF TRACE METALS ESPECIALLY IRON IN OILS AND FATS IS KNOWN TO PRODUCE DELETERIOUS EFFECTS SUCH AS NOTABLE PROXIDIATION ON QUALITY. THE DETERMINATION OF METALS IN VEGETABLE OILS AND FATS HAS BEEN UNDER INVESTIGATION FOR SEVERAL YEARS AND IS STILL A FORMIDABLE PROBLEM. SEVERAL METHODS FOR THIS ANALYSIS INCLUDING SPECTROPHOTOMETRY [1], ATOMIC ABSORPTION SPECTROMETRY, AND VOLTAMMETRY [2] HAVE BEEN REPORTED. AMONG THE METHOD FOR THE ANALYSIS, DIGESTION OR EXTRACTION OF IRON FROM OIL MATRICES IS A CHALLENGING ISSUE. THE AIM OF THIS STUDY WAS TO DEVELOP A SIMPLE EXTRACTING PROCEDURE BASED ON DLLME AND PREPARATION OF IRON-PHENANTROLINE COMPLEX TO DETERMINE BY SPECTROPHOTOMETRY. THE MAIN DIFFERENCE OF THE DEVELOPED DLLME METHOD COMPARED TO USUAL ONES IS EXTRACTION OF A WATER SOLUBLE ANALYTE (IRON) FROM A LIPOPHILIC (OIL) MATRIX [3].PARAMETERS AFFECTING THE EXTRACTION SUCH AS HYDROXYLAMINE AMOUNT, 1, 10 ORTHOPHENANTROLINE CONCENTRATION, CENTRIFUGATION TIME AND SPEED, TIME INTERVAL BETWEEN THE ADDITION OF HYDROXYLAMINE AND ORTHOPHENANTROLINE, TEMPERATURE, PH AND SALT WERE INVESTIGATED. STANDARD ADDITION WAS USED TO CONSTRUCT CALIBRATION CURVE ON THE OIL. VALIDATION PARAMETERS INCLUDING PRECISION, ACCURACY, LINEARITY RANGE AND LOQ WAS DETERMINED. THE VALIDATED METHOD WAS APPLIED TO IRON DETERMINATION IN THE REAL SAMPLES.OPTIMUM EXTRACTING CONDITIONS WERE OBTAINED TO BE: HYDROXYLAMINE: 50ML, ORTHOPHENANTROLINE: 200ML, CENTRIFUGATION TIME: 10 MIN AT 3600 RPM, LEAST TIME INTERVAL BETWEEN THE ADDITION OF ORTHOPHENANTROLINE AND HYDROXYLAMINE, AMBIENT TEMPERATURE, NEUTRAL PH, AND NO SALT ADDITION. RESULTS DEPICTED THAT THE METHOD IS LINEAR IN THE RANGE OF 0.08 TO 0.5 MG/L, RSD% WAS LESS THAN 5%, ERROR% WAS LOWER THAN 4% AND LOQ OF THE METHOD WAS 0.04 MG/L. DETERMINATION OF IRON IN SOME COMMERCIAL VEGETABLE OILS IN THE LOCAL MARKET SHOWED THAT ALL OF THEM HAD IRON CONCENTRATION OF LESS THAN 0.5 MG/L.

IN THIS RESEARCH, A SIMPLE, RAPID AND ENVIRONMENTALLY FRIENDLY METHOD WAS APPLIED FOR THE MICROEXTRACTION, PRECONCENTRATION AND DETERMINATION OF ULTRATRACE QUANTITIES OF SAFRANINO IN SOME WATER AND WASTEWATER SAMPLES BY SUPRAMOLECULAR DISPERSIVE LIQUID–LIQUID MICROEXTRACTION BASED ON THE SOLIDIFICATION OF FLOATING ORGANIC DROPLET (SM-DLLME-SFO) COUPLED WITH SPECTROPHOTOMETRY UV-VIS...