Associação do complexo trans-[Pt(5-heptil-odztH)₂(PPh₃)₂] em um sistema microemulsionado e estudos de viabilidade celular, fagocitose e atividade microbicida

Abstract

In recent years, the search for systems to deliver products with therapeutic potential whose purpose is to increase efficiency, reduce toxicity and improve bioavailability has increased. Being a mixture of oil and water, surfactants and co-surfactants, Microemulsions (MEs) are homogeneous, translucent and thermodynamically stable dispersions, generating modified systems for the release of drugs, natural or synthetic products that have low solubility in an aqueous medium. The objective of this work was to prepare and characterize a microemulsion (ME) associated with the complex trans-[Pt(5-heptil-odztH)₂(PPh₃)₂] and verify its biological effect on cell activation. MEs were prepared using Span 80 (SP), Tween 80 (TW), 1-butanol (BT), forming the SP/TW/BT system (3.5:5.5:1.0), distilled water and triglyceride of capric/caprylic acid associated with the Pt(II) complex. pH measurements remained at 6.4 and electrical conductivity remained between 7 and 8 μS.cm⁻¹. The rheological characterization presented a Newtonian flow profile, the ME associated with the Pt(II) complex presented the hysteresis area value closest to zero (˗0.66 Pa s⁻¹) than the unassociated ME (0.66 Pa s⁻¹), indicating greater stability of the complex/ME set. The Zeta potential results of ˗14.8±5.72 mV for the ME not associated with the complex and ˗19.2±4.49 mV for the associated ME, with Dynamic Light Scattering (EDL) we obtain particle sizes in the range of 160 nm. Cell viability tests showed values above 95% and phagocytosis rates between 30 and 42% in 30 min incubations, showing promise for future tests.