Development of a new inversion-voltammetric technique in determining inorganic iodine in Laminariae thalli L. for the quality control of raw materials in factory laboratories

Objectives. To develop and validate a methodology for determining inorganic iodine in Laminariae thalli L., corresponding to the norms of the State Pharmacopoeia of the Russian Federation, 15th edition (SPh 15). The methodology needs to be valid and suitable for the quality control of pharmaceutical raw materials in factory laboratories. Methods. Cathode inversion voltammetry was used as an instrumental method for determining inorganic iodine using a graphite electrode capable of sorbing electroactive ion associates of surfactant–iodine. Results. When compared with the titrimetric technique recommended by SPh 15, the proposed technique is more selective, sensitive and less time-consuming. The efficiency and metrological characteristics of the technique were confirmed by validation in accordance with the requirements of SPh 15. Conclusion. The paper presents a new method for determining the gross content of inorganic iodine in Laminariae thalli L. This technique can be used not only in scientific research, but also in the routine quality control of medicinal plant raw materials in control and analytical laboratories engaged in pharmaceutical quality control.