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Introduction. When developing drugs it is necessary to use laboratory equipment that simulates pilot and industrial equipment. For the production of semi-solid preparations the key equipment are rotor-stator dispersers and vacuum reactors-homogenizers. Aim. Investigation of the functional characteristics of laboratory equipment: Megatron® MT 1-50 dispersant SHS F/2 (Kinematica AG, Switzerland) and the RP-5 vacuum homogenizer reactor (Promvit, Ukraine). Materials and methods. During development a generic product Penciclovir cream 1% the initial particle size in suspension of penciclovir and particle size after grinding were studied by optical microscopy and laser diffraction methods. In a cream made in the reactor, the particle size of the dispersed phase of the o/w emulsion and suspension, as well as the absence of air bubbles, were determined by optical microscopy. The assay of penciclovir in 9 samples of the cream taken from the reactor-homogenizer was performed by liquid chromatography. By the of rotational viscometry method the rheological properties of the cream were studied. By the inductively coupled plasma atomic emission spectroscopy the getting of metal impurities from the disperser and the reactor-homogenizer into the suspension and cream were investigated. Results and discussion. With an increase in the rotor speed, the particle size of penciclovir in suspension decreases. The disperser effectively performs its function at a rotor speed of 25,000 rpm. In a cream made in the reactor, the deviations in the quantitative content of penciclovir from the average value in each sample are within the uncertainty of the analytical procedure, which indicates its uniform distribution. The reactor provides effective dispersion and uniform distribution of the oil phase, prevents the formation of a gas emulsion and allows getting a cream that, according to its rheological properties, corresponds to the reference preparation Fenistil® Pencivir cream 1%. In the production process metal impurities were not emitted into the suspension and the cream from the equipment. Conclusion. The disperser and the reactor during the production of cream with penciclovir are suitable for their intended use. It is rational to combine these two types of equipment at the sites for the production of semi-solid preparations. The disperser can also be used to produce emulsions with a very small particle size of the dispersed phase.

Voltammetric responses associated with the simple reaction of perrhenate anions transfer across polarized micro-interfaces between two immiscible electrolyte solutions (micro-ITIES) was investigated, and their sensing applications were demonstrated. The micro-ITIES array was formed at polyethylene terephthalate membranes containing a 196 microhole array of radius 10.0±0.1 μm using a femtosecond laser. The characteristics of perrhenate ions transfer at the water/2-nitrophenyloctyl ether interface were first investigated using cyclic voltammetry (CV). CV was used in the estimation of some of the perrhenate anions thermodynamic parameters, such as the formal transfer potential and the Gibbs transfer energy. The technique of alternating current stripping voltammetry (ACSV) was also utilized to improve the sensitivity of the perrhenate anion detection. Under optimized preconcentration and detection conditions, a limit of detection of 0.3 μM with a wide linear dynamic range extending from 1.0 to 100 μM was achieved. The effect of various potential interfering anions on the perrhenate sensor was also investigated and an excellent selectivity over SCN-, I-, NO3-, NO2-, CO32-, SO42-, MoO42-, WO42- and CH3COO- ions was also achieved. This enabled quantitative measurements of rhenium in some mineral raw samples and the data was also validated by comparing with inductively coupled plasma atomic emission spectroscopy.