Construction of Double-Shelled Hollow Ag2S@Polydopamine Nanocomposites for Fluorescence-Guided, Dual Stimuli-Responsive Drug Delivery and Photothermal Therapy

Abstract

The design and preparation of multifunctional drug carriers for combined photothermal–chemotherapy of cancer have attracted extensive attention over the past few decades. However, the development of simple-structured stimuli-responsive theranostic agents as both photothermal agents and chemotherapeutic agents remains a big challenge. Herein, a novel double-shelled nanocarrier composed of hollow Ag2S (HAg2S) nanospheres and a mesoporous polydopamine (MPDA) exterior shell was fabricated through a facile process. Notably, HAg2S possesses both fluorescence and photothermal properties. MPDA acts as a drug carrier and photothermal agent. Meanwhile, the cavity structure between HAg2S and MPDA provides more space for drug loading. The nanocarrier presents a high drug loading rate of 23.4%. It exhibits an apparent pH-responsive DOX release property due to the acidic sensitivity of PDA. In addition, the release of DOX is promoted under NIR irradiation, which is attributed to the heating action generated by the photothermal effect of HAg2S and MPDA. The cytotoxicity test shows that the nanocarriers possess good biocompatibility. Compared with single photothermal therapy or chemotherapy, the combined treatment represents a synergistic effect with higher therapeutic efficacy. In addition, the nanocarriers exhibit excellent fluorescence imaging capability and can target HepG2 cells. These simple-structured smart nanocarriers have a great potential for fluorescence-mediated combination cancer therapy.

Frontiers in Preparations and Promising Applications of Mesoporous Polydopamine for Cancer Diagnosis and Treatment

“…Material selection and removal are the key processes of hard templating; self-assembly and carbonization are essential for soft templating. The following content is an introduction to both templating methods [ 15 ].…”

“…Relatively soft surfactants such as high-molecular-weight block copolymers or molecular polymers are often used as soft templates. For example, triblock copolymers F127 or P123, cetyltrimethylammonium bromide, or polyoxymethylene-polybutene deblock copolymer, which have strong electrostatic and hydrogen bonding interactions with precursors, can be used to produce diverse morphology through relatively simple synthesis processes [ 15 ]. The chemical reaction between the template and the carbon precursor, the ratio of reactants, and the reaction temperature are important factors for templating.…”

“…Collectively, it has proven that Fe 3 O 4 @Void@MPDA is an ideal agent to be employed in tumor photothermal therapy. In a further example, Gao et al developed double-shelled hollow Ag 2 S@PDA nanocomposites [ 15 ]. These researchers used cetyltrimethylammonium bromide (CTAB) as a soft template to coat the HAg 2 S nanospheres with a silicon layer.…”

Ultrasensitive Detection and Cellular Photothermal Therapy via a Self‐Photothermal Modulation Biosensor

“…As a spatiotemporally controllable cancer therapy method, PTT, with the advantages of low cost, good specificity, and slight side effects on normal tissues, has attracted wide attention. [14] Various nanomaterials are currently being explored as novel photothermal agents, [16][17][18][19][20] which lays the foundation for further diagnosis-treatment integration.Optical microfibers, which are an important group of evanescent optical biosensors, are small in size, light in weight, immune to electromagnetic interference, and low in cost, and they are quite suitable for use at an early stage. [21,22] These tiny fibers offer engineerable waveguiding properties, such as fractional evanescent fields and surface intensity.…”

“…As a spatiotemporally controllable cancer therapy method, PTT, with the advantages of low cost, good specificity, and slight side effects on normal tissues, has attracted wide attention. [14] Various nanomaterials are currently being explored as novel photothermal agents, [16][17][18][19][20] which lays the foundation for further diagnosis-treatment integration.…”