Low‐Intensity Light‐Responsive Anticancer Activity of Platinum(II) Complex Nanocolloids on 2D and 3D In Vitro Cancer Cell Model

Abstract

This study aimed to evaluate the therapeutic efficacy of low-intensity visible light responsive nanocolloids of a Pt-based drug using a 2D and three-dimensional (3D) in vitro cancer cell model. Biocompatible and biodegradable polymeric nanocolloids, obtained using the ultrasonication method coupled with Layer by Layer technology, were characterized in terms of size (100 ± 20 nm), physical stability, drug loading (78%), and photoactivation through spectroscopy studies. The in vitro biological effects were assessed in terms of efficacy, apoptosis induction, and DNA-Pt adducts formation. Biological experiments were performed both in dark and under visible light irradiation conditions, exploiting the complex photochemical properties. The light-stimuli responsive nanoformulation gave a significant enhancement in drug bioactivity. This allowed us to achieve satisfying results by using nanomolar drug concentration (50 nM), which was ineffective in darkness condition. Furthermore, our nanocolloids were validated in 3D in vitro spheroids using confocal microscopy and cytofluorimetric assay to compare their behavior on culture in 2D monolayers. The obtained results confirmed that these nanocolloids are promising tools for delivering Pt-based drugs.

Synthesis of a light-responsive platinum curcumin complex, chemical and biological investigations and delivery to tumor cells by means of polymeric nanoparticles

“…They found a stronger green fluorescence associated with curcumin in the synthesized nanoparticles in comparison to the free complex. In our previous work, 49,50 we have already demonstrated that also the fluorescence of curcumin alone decays after 1 h of incubation.…”

“…Ultrasonication assisted layer by layer technology was employed for the preparation of nanocolloids. 49,50 Dynamic light scattering (DLS) measurements revealed that the size of nanocolloids was uniform, and the average diameter was 190 ± 10.32 nm (Fig. 1a).…”

“…47,48 In addition, loading light-stimuli small molecule drugs into delivery systems, such as polymeric nanoparticles or micelles, liposomes or mesoporous silica, allows drug accumulation and therapeutic effects to be increased. 49,50 Natural biopolymers such as pectin, alginate and chitosan have recently found wide applications in food and pharmaceutical elds. 51 The presence of functional groups in biopolymer structures improves the encapsulation of bioactive compounds and drugs as well as the formation of a cross-linked dense network aer encapsulation.…”

“…Pectin and chitosan are known to combine to form a polyelectrolyte complex which can be used to encapsulate bioactive molecules and drugs. 56 Following our work in the eld of bioactive Pt(II) complexes, 31,32,49,50 we prepared and studied a Pt(II) complex of formula [Pt(ppy)(curc)] (ppy = deprotonated 2-phenylpyridine and curc = deprotonated curcumin) with the aim to extend studies on the potential application of transition metal complexes as a pharmacological tool. The ultrasonication method coupled with the layer-by-layer technology was used to prepare chitosan and pectin polymeric nanocolloids to encapsulate [Pt(ppy)(curc)] affording the material denoted as Pt(ppy)(curc)-NCs.…”

Study of the laser radiation effect in combination with doxorubicin on the survival of MCF7 and MCF7DOX culture cells

“…The dynamic balance of metabolic processes that underlie the restoration or, conversely, the degradation of the cell's vital functions is disturbed [41,42]. Apoptosis due to ROS-induced ROS production can be a predictable phenomenon because it is an evolutionarily programmed scenario if metabolic changes become incompatible with normal functioning [43,44]. The initiation of apoptosis processes may seem all the more likely when we understand that destructive changes in the cell are generated not by one but by several influencing factors: laser irradiation and doxorubicin [45,46].…”