pH-Responsive Drug Delivery and Imaging Study of Hybrid Mesoporous Silica Nanoparticles

Abstract

A system of pH-responsive and imaging nanocarriers was developed using mesoporous silica nanoparticles (MSNs), in which gadolinium (Gd) was doped through in situ doping (Gd2O3@MSN). Sodium alginate (SA) was attached to the surfaces of the amino groups of MSNs (NH2-Gd2O3@MSN) through the electrostatic adsorption between the amino groups and the carboxyl groups with the formation of hybrid SA-Gd2O3@MSN nanoparticles (NPs). The SA-coated NPs were spherical or near-spherical in shape with an average size of nearly 83.2 ± 8.7 nm. The in vitro drug release experiments of a model rhodamine B (RhB) cargo were performed at different pH values. The result confirmed the pH-responsiveness of the nanocarriers. The results of the cytotoxicity studies indicated that the SA-Gd2O3@MSN NPs were not cytotoxic by themselves. The results of the in vivo safety evaluation and the hemolysis assay confirmed that the system is highly biocompatible. It is noteworthy that the T1 contrast of the system was significantly enhanced by the Gd, as indicated by the result of the MR imaging. This study confirms that the synthesized hybrid nanosystem is promising for pH-responsive drug delivery and MR imaging for cancer diagnosis and treatment.

cRGD-Conjugated GdIO Nanoclusters for the Theranostics of Pancreatic Cancer through the Combination of T1–T2 Dual-Modal MRI and DTX Delivery

“…Blood compatibility was evaluated according to the previously reported hemolysis test [ 46 , 47 , 48 , 49 , 50 ]. Red blood cells (RBCs) were first separated from the remaining blood by centrifugation at 2500 rpm for 6 min at 4 °C.…”

A Novel pH-Responsive Iron Oxide Core-Shell Magnetic Mesoporous Silica Nanoparticle (M-MSN) System Encapsulating Doxorubicin (DOX) and Glucose Oxidase (Gox) for Pancreatic Cancer Treatment

“…Fe 3 O 4 nanoparticles with a size of 11.16 ± 0.94 nm were prepared by the ferric oleate pyrolysis method, 36 , 37 and well-dispersed M-MSNs with an average size of 59.55 ± 3.36 nm were prepared by the conventional Stöber method. 35 , 38–40 As shown in Figure 1B–E , the DG@NPs were slightly larger (66.02 ± 3.6 nm) than the M-MSNs, which was due to the successful incorporation of PDA-PEG-FA on the M-MSN surface. The elemental content in the M-MSNs was then further analyzed using energy spectroscopy ( Figure 1F ), which allowed differentiation between the elements Fe, Si and O contained within the nanoparticles.…”

“…In this study, a hemolytic assay method from the literature 34 , 35 was used to assess the hemocompatibility of the material. First, erythrocytes were centrifuged at 20 °C and 2000 rpm for 10 min and washed three times with saline to obtain a purified erythrocyte suspension.…”

Current Principles, Challenges, and New Metrics in pH-Responsive Drug Delivery Systems for Systemic Cancer Therapy

“…The results of the in vivo safety assessment and hemolysis analysis confirmed the high biocompatibility of this system. MRI experiments on a mouse model of breast cancer showed particle accumulation in the 4T1 tumor, which points to the perspective of proposed systems application in pH-responsive drug delivery, and MRI imaging for cancer diagnosis and treatment [ 261 ]. Besides mesoporous silica particles, hybrid carriers based on them have also been extensively studied in vivo.…”