Magnetic drug carriers: bright insights from light-responsive magnetic liposomes

Facile synthesis of porous MoS2nanofibers for efficient drug delivery and cancer treatment

Porous MoS₂nanofibers were synthesized by electroplating and post-annealing and applied in a responsive drug delivery system. The one-dimensional (1D) MoS₂nanofibers displayed a high specific surface area, controllable morphology, and uniform size, serving as a promising drug carrier for chemotherapy. After surface modification with polyethylene glycol (PEG) through PEGylation, the MoS₂/PEG composite displayed excellent physical/chemical stability and biocompatibility. More importantly, MoS₂/PEG loaded with doxorubicin (DOX) exhibited a controllable release responsive to pH and near-infrared (NIR) irradiation and demonstrated precise DOX dose release. Such remarkable anticancer effects were mainly attributed to outstanding photothermal performance and stability of porous MoS₂nanofibers. This work offered a new opportunity of employing porous MoS₂nanofibers as drug carriers for effective cancer chemotherapy.

Magnetoliposomes: recent advances in the field of controlled drug delivery

INTRODUCTION

Magnetoliposomes have gained increasing attention as delivery systems, as they surpass many limitations associated with liposomes. The combination with magnetic nanoparticles provides a means for development of multimodal and multifunctional theranostic agents that enable on-demand drug release and real-time monitoring of therapy.

AREAS COVERED

Recently, several magnetoliposome structures have been reported to ensure efficient transport and delivery of therapeutics, while improving magnetic properties. Besides, novel techniques have been introduced to improve on-demand release, as well as to achieve sequential release of different therapeutic agents. This review presents the major types and methods of preparation of magnetoliposomes, and discusses recent strategies in the trigger of drug release, development of theranostic formulations, and delivery of drugs and biological entities.

EXPERT OPINION

Despite significant advances in efficient drug delivery, current literature lacks an assessment of formulations as theranostic agents and complementary techniques to optimize thermotherapy efficiency. Plasmonic magnetoliposomes are highly promising multimodal and multifunctional systems, providing the required design versatility to optimize theranostic capabilities. Further, photodynamic therapy and delivery of proteins/genes can be improved with a deeper research on the employed magnetic material and associated toxicity. A scale-up procedure is also lacking in recent research, which is limiting their translation to clinical use.

Recent Advances in Extracellular Vesicles as Drug Delivery Systems and Their Potential in Precision Medicine

Extracellular vesicles (EVs) are membrane-bilayered nanoparticles released by most cell types. Recently, an enormous number of studies have been published on the potential of EVs as carriers of therapeutic agents. In contrast to systems such as liposomes, EVs exhibit less immunogenicity and higher engineering potential. Here, we review the most relevant publications addressing the potential and use of EVs as a drug delivery system (DDS). The information is divided based on the key steps for designing an EV-mediated delivery strategy. We discuss possible sources and isolation methods of EVs. We address the administration routes that have been tested in vivo and the tissue distribution observed. We describe the current knowledge on EV clearance, a significant challenge towards enhancing bioavailability. Also, EV-engineering approaches are described as alternatives to improve tissue and cell-specificity. Finally, a summary of the ongoing clinical trials is performed. Although the application of EVs in the clinical practice is still at an early stage, a high number of studies in animals support their potential as DDS. Thus, better treatment options could be designed to precisely increase target specificity and therapeutic efficacy while reducing off-target effects and toxicity according to the individual requirements of each patient.

Pluronic F127 self-assembled MoS2 nanocomposites as an effective glutathione responsive anticancer drug delivery system

In this study, bio-responsive polymeric MoS₂ nanocomposites were prepared for use as a drug carrier for cancer therapy. Herein, we report the synthesis and demonstrate the self-assembly of pluronic F127 (PF127) on a cystamine–glutathione–MoS₂ (CYS–GSH–MoS₂) system, which can be used for GSH-triggered drug release under biological reducing conditions. The reduction-sensitive disulfide bond containing CYS was incorporated between the amphiphilic copolymer PF127 and GSH–MoS₂ to achieve feasible drug release. Percent drug loading capacity and encapsulation efficiency were 51.3% and 56%, respectively. In addition, when the MoS₂–GSH–CYS–PF127 nanocomposite was incubated in a GSH environment, the morphology of the nanocomposite tended to change, ultimately leading to drug release. The drug-loaded PF127–CYS–GSH–MoS₂ polymeric nanocomposites efficiently released 52% of their drug content after 72 h of incubation in a GSH reduction environment. The HeLa cells treated with DOX loaded MoS₂–GSH–CYS–PF127 showed 38% toxicity at drug concentration of 40 μg, which indicated that the successfully released of drug from carrier and caused the cell death. Further, fluorescence microscopy images of HeLa cells revealed the potential behavior of the MoS₂–GSH–CYS–PF12 nanocomposite during the 2- and 4 h incubation periods; the nanocomposite was only found in the cytoplasm of HeLa cells. Interestingly, after 6 h of incubation, the drug was slowly released from the nanocomposite and could enter the nucleus as confirmed by fluorescence imaging of HeLa cells. Altogether, our synthesized PF127-coated MoS₂ nanocomposite could be effectively adopted in the near future as a GSH-sensitive drug carrier.

In this study, bio-responsive polymeric MoS₂ nanocomposites were prepared for use as a drug carrier for cancer therapy.

Intelligent MoS2 Nanotheranostic for Targeted and Enzyme-/pH-/NIR-Responsive Drug Delivery To Overcome Cancer Chemotherapy Resistance Guided by PET Imaging

Chemotherapy resistance remains a major hurdle for cancer therapy in clinic because of the poor cellular uptake and insufficient intracellular release of drugs. Herein, an intelligent, multifunctional MoS₂ nanotheranostic (MoS₂-PEI-HA) ingeniously decorated with biodegradable hyaluronic acid (HA) assisted by polyethyleneimine (PEI) is reported to combat drug-resistant breast cancer (MCF-7-ADR) after loading with the chemotherapy drug doxorubicin (DOX). HA can not only target CD44-overexpressing MCF-7-ADR but also be degraded by hyaluronidase (HAase) that is concentrated in the tumor microenvironment, thus accelerating DOX release. Furthermore, MoS₂ with strong near-infrared (NIR) photothermal conversion ability can also promote the release of DOX in the acidic tumor environment at a mild 808 nm laser irradiation, achieving a superior antitumor activity based on the programmed response to HAase and NIR laser actuator. Most importantly, HA targeting combined with mild NIR laser stimuli, rather than using hyperthermia, can potently downregulate the expression of drug-resistance-related P-glycoprotein (P-gp), resulting in greatly enhanced intracellular drug accumulation, thus achieving drug resistance reversal. After labeled with ⁶⁴Cu by a simple chelation strategy, MoS₂ was employed for real-time positron emission tomography (PET) imaging of MCF-7-ADR tumor in vivo. This multifunctional nanoplatform paves a new avenue for PET imaging-guided spatial-temporal-controlled accurate therapy of drug-resistant cancer.