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Il contributo presenta alcune azioni in corso all’interno del progetto europeo INES (http://ines.unibo.it/), finanziato nell’ambito E+ Cooperation Partnership in School Education, coordinato dall’Università di Bologna (2021-2024). Il progetto si propone di realizzare Risorse Educative Aperte (OERs) e interventi formativi per ridurre il problema della droga, in particolare delle NPS, nel contesto della scuola secondaria di secondo grado. Il progetto ha una matrice fortemente interdisciplinare e si fonda su un costante lavoro di collaborazione tra ricercatori, insegnanti e studenti ed esperti esterni.

A new fast capillary electrophoretic method has been developed for the analysis of the glycopeptide antibiotic vancomycin in formulations. An electrophoretic run is completed within 3.0 min; fused silica capillaries (100 um i.d., 8.5 cm effective length and 48.5 cm total length) and a background electrolyte consisting of 12.5 mM, pH 2.5 phosphate buffer are used. The applied voltage is 20.0 kV; samples are injected by pressure (30 mbar×3 s) at the anodic end of the capillary. The method was successfully applied to innovative controlled release microparticles consisting of a coated albumin core containing vancomycin. A simple procedure has been developed to obtain complete vancomycin extraction from microparticles using a 5% (w/v) sodium dodecyl sulphate aqueous solution. The method has been validated in terms of linearity, precision and accuracy. Good linearity was found in the 0.25–5.00 ug/mL range. Satisfactory precision was obtained, with relative standard deviation values always lower than 3.9%; accuracy was satisfactory, with recovery values between 97.8 and 102.2%. The method is also suitable for vancomycin determination in commercial capsules.

A high-performance liquid chromatographic method for the determination in human plasma of the recent noradrenergic and specific serotonergic antidepressant (NaSSA) mirtazapine and its two main metabolites, N-desmethylmirtazapine and 8-hydroxymirtazapine, has been developed. Fluorescence detection was used, exciting at 290 nm and monitoring emission at 370 nm. Separation was obtained by using a reversed phase column (C8, 250 mm×4.6 mm I.D., 5 um) and a mobile phase composed of 75% aqueous phosphate buffer containing triethylamine at pH 3.0 and 25% acetonitrile. Melatonin was used as the internal standard. A careful pre-treatment of plasma samples was developed, using solid-phase extraction with phenyl cartridges (100 mg, 1 mL). The calibration curves were linear over a working range of 5–150 ng/mL for mirtazapine and of 2.5–75.0 ng/mL for N-desmethylmirtazapine and 8-hydroxymirtazapine. The limit of quantitation (LOQ) was 2.5 ng/mL and the limit of detection (LOD) was 1.25 ng/mL for all analytes. The method was applied with success to plasma samples from depressed patients undergoing treatment with mirtazapine. Precision data, as well as accuracy results, were satisfactory and no interference from other drugs was found. Hence the method is suitable for therapeutic drug monitoring of mirtazapine and its metabolites in depressed patients’ plasma.

An original capillary electrophoretic method has been developed and applied for the enantioselective analysis of the antiparkinson drug biperiden in pharmaceutical formulations, using a modified cyclodextrin as the chiral selector. Baseline enantioseparation of the racemic compound was achieved in less than 7 min using an uncoated fused silica capillary (50 um i.d. and 48.5, 40.0 cm, total and effective length, respectively), filled with a background electrolyte consisting of a 50mM phosphate buffer at pH 3.5 supplemented with 3% (w/v) beta-cyclodextrin sulphate and applying a voltage of 20 kV, reversed polarity. Samples were injected by pressure (50 mbar, 90 s) at the cathodic end of the capillary and detection wavelength was 195 nm (bandwidth: 10 nm). A simple and fast pre-treatment procedure allowed the complete extraction of the drug from commercial formulations (sustained release tablets and ampoules for injections) without any interference from the matrix. Good linearity was found in the 1–50 ug/mL concentration range; the limit of quantitation was 1ug/mL and the limit of detection was 0.4 ug/mL. Precision and accuracy were good, with R.S.D. values always lower than 2.8% and a mean recovery value of 101.1%. The method was suitable for the quality control of biperiden in commercial formulations.

A reliable and sensitive high performance liquid chromatographic method for the determination of the recent antidepressant citalopram and two metabolites in human plasma has been developed. Fluorescence detection at 300 nm was used, exciting at 238 nm. Separation was obtained using a reversed-phase column (C18, 250x3.0 mm i.d., 5 mm) and a mobile phase: 40 % acetonitrile: 60 % aqueous tetramethylammonium perchlorate (pH 1.9). Calibration curves were linear over a working range 5-300 ng mL-1 for citalopram, 2.5-150.0 ng mL-1 for desmethylcitalopram and 2.5-50.0 ng mL-1 for didesmethylcitalopram. The limits of quantitation (LOQ) were 1.5 ng mL-1 for citalopram and desmethylcitalopram and 2.0 1.5 ng mL-1 for didesmethylcitalopram. Precision data, as well as accuracy, were satisfactory and no interference from different psychotropic drugs was found. The method was therefore suitable for therapeutic drug monitoring of citalopram and its active metabolites in plasma of depressed patient.

Real time ultrasound (US) was used to examine 165 consecutive inpatients with clinically suspected deep vein thrombosis of lower limbs. In order to evaluate accuracy, the results of non-invasive techniques were compared with ascending venography, performed in all patients. Assessment included only femoro-popliteal veins, because of difficulty in visualizing calf vein with US. Diagnosis of thrombosis was based on noncompressibility of the examined veins; pulsed Doppler provided further information by evaluating blood flow. In our series Duplex ultrasound was very accurate in detecting acute thrombosis of the proximal veins, sensitivity being 97% and specificity 98%. With US it is also possible to detect conditions that mimic deep vein thrombosis, such as muscular rupture, hematoma, popliteal cyst or compressive tumors. In conclusion US is considered a valid alternative to contrast venography in the diagnosis of proximal vein thrombosis of lower limbs.

A sensitive and accurate method for the spectrofluorimetric determination of trace levels of aluminum in hemodialysis solutions using Mordant Red 19 as the complexation reagent has been developed. The optimal experimental conditions for the concentration of fluorimetric reagent, pH, temperature, and the specific type of matrix are reported. The emission of the fluorescent metal chelate was measured at 555 nm, excitation at 478 nm. Linearity between emission intensity and aluminum concentration was found in the 2-20 ppb range in standard aluminum solutions. Limit of detection was 0.4 ppb. The aluminum amounts in some commercial hemodialysis solutions were determined by means of the extrapolation method. The proposed method proved to be suitable in terms of sensitivity and accuracy for the determination of aluminum in dialysis fluids.