Avaliação da estabilidade do teor de Captopril para administração por sondas de nutrição enteral de diferentes materiais plásticos

Abstract

The use of enteral nutrition tubes (ENT) has been growing as an important alternative for hospitalized or those in home care. The choice of this method of administration should happen when there is no possibility of the patient swallowing his/her own food, to avoid malnutrition and other aggravations resulting from nutritional poverty. In the case of need for medication administration by this route, due to the lack of formulations on the market suitable for use via ENT, it becomes necessary to adapt this administration. Captopril is an antihypertensive angiotensin-converting enzyme inhibitor (iACE) widely used as treatment incthe reduction of cardiac load and blood pressure. Because it is highly susce tible to oxidative degradation due to the influence of temperature, humidity, and pH, it was chosen as a study target, and the stability of captopril tablets after passing through the ENT was evaluated, using the Hospital Geral Waldemar de Alcântara (HGWA) administration protocol as basis. *The solutions obtained through the protocol were evaluated by High Performance Liquid Chromatography (HPLC) coupled with UV-VIS and diode array detector (DAD), using C18 column, mobile phase methanol: phosphoric acid (45:55, v/v, pH 3.0), flow rate 1.0 mL/min and wavelength of 220 nm, being evaluated the linearity and content of the tablets. Nasoenteral probes made of polyvinyl chloride (PVC), polyurethane and silicone were used, in which the captopril content after passing through the tube and the interaction of the plastic material with captopril were evaluated by Fourier transform infrared spectrophotometry (FTIR) and differential exploratory calorimetry (DSC) techniques. Analysis of the tablets by HPLC-UV resulted in a retention time = 4.0 min and analytical curve between 30 to 80 µg/mL, with a correlation coefficient of 0.9951. The average content of the tablets was 103.5%, and after passing through the PVC tube was 102.81%, polyurethane 106.22% and silicone 99.01%, values within the specification recommended by the Brazilian Pharmacopeia. By using the FTIR technique no bands were observed to characterize the drug present in the plastic material sample. In the DSC technique for the tablet and the Reference Substance, endothermic events were obtained in the onset temperatures of 101.67 °C and 104.39 °C, respectively. The analysis of the material in contact with the captopril solution did not show any event that characterized the interaction between captopril and the different materials. It is concluded that the administration of captopril by enteral nutrition probes is safe.