Formulation of Chitosan-Coated Brigatinib Nanospanlastics: Optimization, Characterization, Stability Assessment and In-Vitro Cytotoxicity Activity against H-1975 Cell Lines

Abstract

The purpose of the current study was to develop Brigatinib (BGT)-loaded nanospanlastics (BGT-loaded NSPs) (S1-S13) containing Span 60 with different edge activators (Tween 80 and Pluronic F127) and optimized based on the vesicle size, zeta potential (ZP), and percent entrapment efficiency (%EE) using Design-Expert^® software. The optimum formula was recommended with desirability of 0.819 and composed of Span-60:Tween 80 at a ratio of 4:1 and 10 min as a sonication time (S13). It showed predicted EE% (81.58%), vesicle size (386.55 nm), and ZP (-29.51 mv). The optimized nanospanlastics (S13) was further coated with chitosan and further evaluated for Differential Scanning Calorimetry (DSC), X-ray Diffraction (XRD), in vitro release, Transmission Electron Microscopy (TEM), stability and in-vitro cytotoxicity studies against H-1975 lung cancer cell lines. The DSC and XRD revealed complete encapsulation of the drug. TEM imagery revealed spherical nanovesicles with a smooth surface. Also, the coated formula showed high stability for three months in two different conditions. Moreover, it resulted in improved and sustained drug release than free BGT suspension and exhibited Higuchi kinetic release mechanism. The cytotoxic activity of BGT-loaded SPs (S13) was enhanced three times in comparison to free the BGT drug against the H-1975 cell lines. Overall, these results confirmed that BGT-loaded SPs could be a promising nanocarrier to improve the anticancer efficacy of BGT.

Keywords: brigatinib; chitosan; cytotoxicity; nanospanlastics; optimization; sustained release.

Figure 1

Response surface plots for the effects of type of surfactant (X1), Span-60:EA ratio (X2), and sonication time (X3) on: (A) EE%; (B) vesicles’ size; and (C) zeta potential, respectively.

Figure 2

Contour plot of different responses.

Figure 2

Contour plot of different responses.

Figure 3

The composition of the optimized formula and its expected responses.

Figure 4

Cube graph for the predicted responses of the optimized formula and desirability.

Figure 5

Comparative DSC thermograms; A. pure BGT; B. Span-60, Tween^® 80, and chitosan physical mixture; C. Span-60, Tween^® 80, Chitosan, and BGT physical mixture; D. the optimized formula.

Figure 6

Comparative XRD of spectra of pure BGT (A); Span-60, Tween^® 80, and chitosan physical mixture (B); and chitosan-coated BGT-loaded NSPs (C).

Figure 7

In-vitro release profile of chitosan-coated NSPs and pure BGT and Best fitted Higuchi release kinetic model.

Figure 8

TEM images of chitosan-coated BGT-loaded NSPs.

Figure 9

Cytotoxicity of BGT-loaded NSPs compared to plain NSPs, BGT solution, and blank formula on H-1975 NSCLC, as determined by a WST-1 assay. Cells were treated with varying concentrations of the drug as indicated for 48 h. Cell cytotoxicity was assessed using the WST1 assay and measured as % of survived cells relative to the non-treated control cells. Results obtained from three independent experiments. Error bars indicate means ± SD (n = 3).