Studies of Melatonin Releasing into Solution from the Surface of Porous Carrier Based on Aluminum Oxide and Polydimethylsiloxane

The means of delivery of active molecules, including melatonin, used in medicine and pharmacology should be safe and effective. The aim of this work is to investigate the possibility of melatonin (MT) release into solutions with different pH values from the surface of aluminum oxide and polydimethylsiloxane (Al
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@PDMS/MT) carrier by liquid chromatography. The data on melatonin release in contact with aqueous media with different pH values (1,7; 4,5; 8,0 and 9,4) corresponding to different parts of the human gastrointestinal tract through which the drug passes are presented in this work. The amount of melatonin released from the carrier surface was determined by a standard, widely used in practice, chromatographic method of reversed-phase HPLC (RP HPLC) with UV detection. The incubation process was carried out at room temperature in a 1:10 ratio (Al
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@PDMS/MT: solution with different pH values) with continuous stirring for a long period of time. Analysis of the results shows a gradual release of melatonin from the surface of the porous carrier into the solutions. During incubation, melatonin release of 50% is observed at 30 minutes, about 60% during incubation for 120 minutes, and at 24–48 hours, release of 70% melatonin into solution is observed. It can be assumed that the carrier with a hydrophilic-hydrophobic surface structure delivers melatonin throughout the entire gastrointestinal tract.