Effects of loading procedures of magnetic nanoparticles on the structure and physicochemical properties of cisplatin magnetic liposomes

A mitochondria-targeting lipid-small molecule hybrid nanoparticle for imaging and therapy in an orthotopic glioma model

Hybrid lipid‒nanoparticle complexes have shown attractive characteristics as drug carriers due to their integrated advantages from liposomes and nanoparticles. Here we developed a kind of lipid-small molecule hybrid nanoparticles (LPHNPs) for imaging and treatment in an orthotopic glioma model. LPHNPs were prepared by engineering the co-assembly of lipids and an amphiphilic pheophorbide a‒quinolinium conjugate (PQC), a mitochondria-targeting small molecule. Compared with the pure nanofiber self-assembled by PQC, LPHNPs not only preserve the comparable antiproliferative potency, but also possess a spherical nanostructure that allows the PQC molecules to be administrated through intravenous injection. Also, this co-assembly remarkably improved the drug-loading capacity and formulation stability against the physical encapsulation using conventional liposomes. By integrating the advantages from liposome and PQC molecule, LPHNPs have minimal system toxicity, enhanced potency of photodynamic therapy (PDT) and visualization capacities of drug biodistribution and tumor imaging. The hybrid nanoparticle demonstrates excellent curative effects to significantly prolong the survival of mice with the orthotopic glioma. The unique co-assembly of lipid and small molecule provides new potential for constructing new liposome-derived nanoformulations and improving cancer treatment.

Anticancer potential of docetaxel-loaded cobalt ferrite nanocarrier: an in vitro study on MCF-7 and MDA-MB-231 cell lines

AIM

To develop a biocompatible cobalt ferrite (CF-NP) nanodrug formulation using oleic acid and poly (d,l-lactide-co-glycolic) acid (PLGA) for the delivery of docetaxel (DTX) specifically to breast cancer cells.

METHODS

The CF-NP were synthesised by hydrothermal method and conjugated with DTX in a PLGA matrix and were systematically characterised using XRD, FE-SEM, TEM, DLS, FTIR, TGA, SQUID etc. The drug loading, in vitro drug release, cellular uptake, cytotoxicity were evaluated and haemolytic effect was studied.

RESULTS

The CF-NP showed good crystallinity with an average particle size of 21 nm and ferromagnetic nature. The DTX-loaded CF-NP (DCF-NP) showed 8.4% (w/w) drug loading with 81.8% loading efficiency with a sustained DTX release over time. An effective internalisation and anti-proliferative efficiency was observed in MCF-7 and MDA-MB-231 breast cancer cells and negligible haemolytic effect.

CONCLUSION

The DCF-NP can have the potential for the effective delivery of DTX for breast cancer treatment.

Synthesis, characterization and in vivo evaluation of a magnetic cisplatin delivery nanosystem based on PMAA-graft-PEG copolymers

The development of anticancer drug delivery systems which retain or enhance the cytotoxic properties of the drug to tumorous tissues, while reducing toxicity to other organs is of key importance. We investigated different poly(methacrylic acid)-g-poly(ethyleneglycol methacrylate) polymers as in situ coating agents for magnetite nanocrystallites. The obtained magnetic nano-assemblies were in turn thoroughly characterized for their structural, colloidal and physicochemical properties (drug loading capacity/release, magnetic field triggered drug release, cell uptake and localization) in order to select the best performing system. With the focus on in vivo validation of such magnetic drug delivery systems for first time, we selected cisplatin as the drug, since it is a potent anticancer agent which exhibits serious side effects due to lack of selectivity. In addition, cisplatin would offer facile determination of the metal content in the animal tissues for biodistribution studies. Alongside post-mortem Pt determination in the tissues, the biodistribution of the drug nanocarriers was also monitored in real time with PET-CT (positron emission tomography/computed tomography) with and without the presence of magnetic field gradients; using a novel chelator-free method, the nanoparticles were radiolabeled with ⁶⁸Ga without having to alter their structure with chemical modifications for conjugation of radiochelators. The ability to be radiolabeled in such a straightforward but very robust way, along with their measured high MRI response, renders them attractive for dual imaging, which is an important functionality for translational investigations. Their anticancer properties were evaluated in vitro and in vivo, in a cisplatin resistant HT-29 human colon adenocarcinoma model, with and without the presence of magnetic field gradients. Enhanced anticancer efficacy and reduced toxicity was recorded for the cisplatin-loaded nanocarriers in comparison to the free cisplatin, particularly when a magnetic field gradient was applied at the tumor site. Post mortem and real-time tissue distribution studies did not reveal increased cisplatin concentration in the tumor site, suggesting that the enhanced anticancer efficacy of the cisplatin-loaded nanocarriers is driven by mechanisms other than increased cisplatin accumulation in the tumors.

Metal ion-assisted drug-loading model for novel delivery system of cisplatin solid lipid nanoparticles with improving loading efficiency and sustained release

Metal ion-assisted drug loading model, in which metal ion was used to modify the microstructure of lipid layer, has been developed to improve drug loading efficiency of solid lipid nanoparticles (SLNs). The microstructure and properties of metal ion-assisted cisplatin-loading SLNs were investigated by infra-red spectroscopy, fluorescence spectroscopy and zetasizer. The reactions of hydrogenated soybean lecithin with Zn(2+), Cu(2+), Mn(2+ )and Mg(2+ )have been detected; the mechanism for higher drug encapsulation efficiency (EE) has been investigated. In metal ion introduction SLNs, the compact degree of the lipid molecules was increased due to the electrostatic interaction between metal ions and phospholipid acyl and choline polarity groups, which result in increasing of drug EE. Meanwhile, these electrostatic interactions slowed the releasing rate of encapsulated drug. The study of cytotoxic activity in vitro indicated that the cell cytotoxicity of metal ions introduction SLNs depended on both cell uptake of SLNs and drug releasing from SLNs.

Preparation and characterization of cisplatin magnetic solid lipid nanoparticles (MSLNs): effects of loading procedures of Fe3O4 nanoparticles

PURPOSE

In order to improve formulation of targeting chemotherapy, cisplatin-loaded magnetic solid lipid nanoparticles (MSLNs) were prepared. In present study, the deliberate loading of Fe3O4 magnetic nanoparticles (MNs) into cisplatin SLNs was developed.

METHODS

SLNs were produced by film scattering ultrasonic technique. The effects of two different loading procedures of MNs on the microstructure and physicochemical properties of MSLNs were investigated by transmission electron microscopy (TEM), zetasizer, infrared spectroscopy (IR), and fluorescence spectroscopy. In vitro drug release and cytotoxicity against human cervical carcinoma SiHa cells, in vivo tumor cell uptake and target tissue distribution of MSLNs under external magnetic field were investigated.

RESULTS

The encapsulation efficiency of cisplatin and the content of MNs in procedure I SLNs were 69.20 ± 4.5% and 2.16 ± 0.53 mg/mL, respectively, which were higher than those of procedure II MSLNs. In procedure I, the MNs, which were combined with lipids during film formation, distributed in the middle of the lipid layer in SLNs. Differently, in procedure II, the MNs and cisplatin were contained in an interior compartment in SLNs, resulting from mixing with drugs during hydration of lipid film. The procedure I MSLNs had higher cytotoxicity than procedure II MSLNs or free cisplatin. With in vivo intratumoral administration, cisplatin concentration in the tumor tissue was maintained at higher level for MSLNs than that for free cisplatin, especially under external magnetic field.

CONCLUSIONS

Procedure I, the developed deliberate MNs loading method, was superior over procedure II in cisplatin encapsulation efficiency, MNs content and cell cytotoxicity.