Mesoporous silica nanoparticles equipped with surface nanovalves for pH-controlled liberation of doxorubicin

Abstract

Silica carriers equipped with molecular and supramolecular pH-sensitive nanovalves were designed by combination of sol-gel synthesis and selective postsynthetic modification. Mesoporous structure of synthesized materials was characterized by low-temperature nitrogen adsorption-desorption, small-angle X-ray diffraction and transmission electron microscopy. Chemical immobilization of N-[N 0 -(N 0 -phenyl)-2-aminophenyl]aminoalkyl groups was confirmed by IR spectral and chemical analyses of surface layer. Loading and release behaviour of synthesized drug carriers was studied in phosphate buffer solutions with pH 5.0 and pH 7.0 using doxorubicin (Dox) as a test molecule. It was found that the loading efficiency of synthesized materials determined by UV spectroscopy measurements reached 59-76%, whereas cumulative value of Dox released from silica materials equipped with molecular and supramolecular nanovalves into the phosphate buffer solution with pH 5.0 reached up to 48% and 51%, respectively. It was proved that aromatic amino groups and surface supramolecular structures localized near pore openings play an essential role in pH-controlled Dox release.

Composite Hydrogel with Oleic Acid-Grafted Mesoporous Silica Nanoparticles for Enhanced Topical Delivery of Doxorubicin

“…In [ 17 , 46 ], the authors pointed out that the drug loading capacity for mesoporous silica nanoparticles with pore diameters of more than 5 nm was higher than that on such particles with pores 2.3 nm in diameter. Similar adsorption isotherms, hysteresis loops, pore size distributions and texture parameters were reported in [ 45 , 47 , 48 ] for silica nanoparticles, while in [ 18 ], the authors presented isotherms and texture parameters indicating practically filled mesopores, significant pore blocking and the subsequent absence of detectable mesoporosity.…”

Synthesis of novel cyclodextrin-modified reduced graphene oxide composites by a simple hydrothermal method

“… 56 The primary amino groups of DOX molecules are mostly protonated when pH is 7.4. 57 As a hydrochloride salt, DOX can interact with β-CD in a 1 : 1 stoichiometry by hydrogen bonding and hydrophobic interactions in phosphate-buffered saline solution, resulting in an inclusion complex. The formation constant ( K f ) was reported to be 210 M −1 (25 °C).…”

Preface to ‘Multifunctional nanostructures for diagnosis and therapy of diseases’

“…Fabrication and organosilane functionalization and characterization of nanostructured ITO electrodes are reported by Pruna et al [10] from Spain. Silica carriers equipped with molecular and supramolecular pH-sensitive nanovalves were designed by combination of sol-gel synthesis and selective postsynthetic modification was studied/ presented by Roik & Belyakova [11] from Ukraine.…”