Quantification of DOX bioavailability in biological samples of mice by sensitive and precise HPLC assay

Context: Doxorubicin (DOX)-loaded folate-targeted poly(3-hydroxybutyrate-co-3-hydroxyoctanoate) [P(HB-HO)] nanoparticles [DOX/FA-PEG-P(HB-HO) NPs] were prepared by the W₁/O/W₂ solvent extraction/evaporation method for applications in cancer treatment. However, the biodistribution, pharmacokinetics, and targeting of the nanoparticles (NPs) have not yet been studied.

Objective: The biodistribution, pharmacokinetics, and targeting of DOX/FA-PEG-P(HB-HO) NPs were evaluated in female BALB/c nude mice bearing HeLa tumors.

Materials and methods: Three DOX formulations were injected into the tail vein of the mice at a dosage of 5?mg/kg. At each time point, blood and various tissues were collected. All samples were then processed and analyzed by a validated high performance liquid chromatographic (HPLC) method.

Results: The t_1/2 values of DOX/P(HB-HO) NPs and DOX/FA-PEG-P(HB-HO) NPs were 2.7- and 3.5-times higher than that of free DOX. No significant difference (p?>?0.05) was found in C_max between the NPs and free DOX. The T_max values of the two NPs were prolonged from 0.25 to 1?h. The AUC_0–t values were 1.55- and 3.05-folds higher than that of free DOX, and MRT increased to 15.99?h for DOX/P(HB-HO) NPs and 25.14?h for DOX/FA-PEG-P(HB-HO) NPs. For DOX/FA-PEG-P(HB-HO) NPs, the DOX content in the tumors were 10.81- and 3.33-times higher than those for free DOX and DOX/P(HB-HO) NPs at 48?h, respectively.

Discussion and conclusions: DOX/FA-PEG-P(HB-HO) NPs displayed reduced cardiac toxicity and improved bioavailability. Moreover, the NPs exhibited a significant extent of DOX accumulation in the tumors, thus suggesting that folate-targeted NPs could effectively transport into HeLa tumors with satisfying targeting.     

Folate-mediated poly(3-hydroxybutyrate-co-3-hydroxyoctanoate) nanoparticles for targeting drug delivery

A novel targeting drug delivery system (TDDS) has been developed. Such a TDDS was prepared by W₁/O/W₂ solvent extraction/evaporation method, adopting poly(3-hydroxybutyrate-co-3-hydroxyoctanoate) [P(HB-HO)] as the drug carrier, folic acid (FA) as the targeting ligand, and doxorubicin (DOX) as the model anticancer drug. The average size, drug loading capacity and encapsulation efficiency of the prepared DOX-loaded, folate-mediated P(HB-HO) nanoparticles (DOX/FA–PEG–P(HB-HO) NPs) were found to be around 240 nm, 29.6% and 83.5%. The in vitro release profile displayed that nearly 50% DOX was released in the first 5 days. The intracellular uptake tests of the nanoparticles (NPs) in vitro showed that the DOX/FA–PEG–P(HB-HO) NPs were more efficiently taken up by HeLa cells compared to non-folate-mediated P(HB-HO) NPs. In addition, DOX/FA–PEG–P(HB-HO) NPs (IC₅₀ = 0.87 μM) showed greater cytotoxicity to HeLa cells than other treated groups. In vivo anti-tumor activity of the DOX/FA–PEG–P(HB-HO) NPs showed a much better therapeutic efficacy in inhibiting tumor growth, and the final mean tumor volume was 178.91 ± 17.43 mm³, significantly smaller than normal saline control group (542.58 ± 45.19 mm³). All these results have illustrated that our techniques for the preparing of DOX/FA–PEG–P(HB-HO) NPs developed in present work are feasible and these NPs are effective in selective delivery of anticancer drug to the folate receptor-overexpressed cancer cells. The new TDDS may be a competent candidate in application in targeting treatment of cancers.     

Folate-modified doxorubicin-loaded nanoparticles for tumor-targeted therapy

Context: Polymeric nanoparticles (NPs) have been used frequently as drug delivery vehicles. Surface modification of polymeric NPs with specific ligands defines a new biological identity, which assists in targeting of the nanocarriers to specific cancers cells.

Objective: The aim of this study is to develop a kind of modified vector which could target the cancer cells through receptor-mediated pathways to increase the uptake of doxorubicin (DOX).

Methods: Folate (FA)-conjugated PEG–PE (FA–PEG–PE) ligands were used to modify the polymeric NPs. The modification rate was optimized and the physical–chemical characteristics, in vitro release, and cytotoxicity of the vehicle were evaluated. The in vivo therapeutic effect of the vectors was evaluated in human nasopharyngeal carcinoma KB cells baring mice by giving each mouse 100?µl of 10?mg/kg different solutions.

Results: FA–PEG–PE-modified NPs/DOX (FA-NPs/DOX) have a particle size of 229?nm, and 86% of drug loading quantity. FA-NPs/DOX displayed remarkably higher cytotoxicity (812?mm³ tumor volume after 13?d of injection) than non-modified NPs/DOX (1290?mm³) and free DOX solution (1832?mm³) in vivo.

Conclusion: The results demonstrate that the modified drug delivery system (DDS) could function comprehensively to improve the efficacy of cancer therapy. Consequently, the system was shown to be a promising carrier for delivery of DOX, leading to the efficiency of antitumor therapy.     

Synthesis,purification, and anticancer effect of magnetic Fe3O4-loaded poly (lactic-co-glycolic) nanoparticles of the natural drug tetrandrine

Abstract

Here, we have successfully synthesised and purified multifunctional PLGA-based nanoparticles by the co-encapsulation of an anticancer drug (tetrandrine) and a magnetic material (Fe₃O₄). The obtained Tet-Fe₃O₄-PLGA NPs had a uniform spherical shape with a particle size of approximately 199?nm and a negative surface charge of –18.0?mV, displaying a high encapsulation efficiency. Furthermore, TEM studies provided representative images of the purification process of the magnetic nanoparticles with MACS^® technology. The MFM and VSM results indicated that both the Fe₃O₄ NPs and Tet-Fe₃O₄-PLGA NPs were superparamagnetic. The DSC spectrum demonstrated that Tet was successfully encapsulated within the PLGA-based nanoparticles. Significantly, the release studies revealed NPs had a relatively slower release rate than free Tet after 8?h’s initial burst release, which had decreased from 98% to 65% after 24?h. In vitro cellular studies revealed that NPs could effectively penetrate into A549 cells and A549 multicellular spheroids to exert cytotoxicity, displaying a significantly high anti-proliferation effect. Moreover, western blot demonstrated that the co-loaded NPs had a higher anticancer activity by injuring lysosomes to activate the mitochondria pathway and induce A549 cell apoptosis. The magnetic characteristics and high anticancer activity support the use of Tet/Fe₃O₄ co-loaded PLGA-based nanoparticles as a promising strategy in the treatment of lung cancer.     

负载阿霉素的黄芩苷纳米粒的制备及其体外性能评价

目的 制备负载阿霉素的黄芩苷纳米粒（DOX/SA-SS-BAI NPs）,并评价其体外性能。方法 构建以胱胺为连接臂的海藻酸钠–黄芩苷聚合物,并负载阿霉素,得到DOX/SA-SS-BAI NPs。对DOX/SA-SS-BAI NPs的理化性质进行表征;采用HepG2细胞进行MTT实验验证其细胞毒性。结果 DOX/SA-SS-BAI NPs粒径为（158.2±2.8）nm,PDI为（0.241±0.008）,Zeta电位为（-24.1±0.3）m V,包封率为（64.34±0.25）%,载药量为（16.22±0.06）%。体外释放显示载药纳米粒具有良好的还原响应性;MTT实验证明DOX/SA-SS-BAINPs对HepG2细胞具有良好的抑制作用;细胞摄取实验表明DOX/SA-SS-BAI NPs在HepG2细胞内较快地释放阿霉素。结论 制备的DOX/SA-SS-BAI NPs具有较好的理化性质和体外抗癌作用。     

Pharmacokinetics and in vivo biodistribution of optimized PLGA nanoparticulate drug delivery system for controlled release of emtricitabine

Abstract

The objective of this study was to develop systematically optimized (OPT) nanoparticles (NPs) providing a controlled release using PLGA of emtricitabine (FTC) employing Formulation by Design (FbD), and evaluate their in vitro and in vivo performance. FTC generates severe adverse effects with risks of toxicity. Thus, NPs were prepared to reduce these drawbacks in this study. The NPs were prepared by water-in-oil-in-water (w/o/w) emulsion method, followed by high-pressure homogenization. The FTC NPs were systematically OPT using 3² central composite design and the OPT formulation located using overlay plot. The pharmacokinetics and in vivo biodistribution of OPT-FTC NPs were investigated in male Wistar rats via the oral administration. Transmission electron microscopy studies on OPT-FTC NPs demonstrated uniform shape and size of particles. In vitro release was sustained up to 15 days in PBS pH 7.4. Augmentation in the values of C_max (1.63 fold) and AUC_0-∞ (5.39 fold) indicated significant enhancement in the rate and extent of bioavailability by the OPT-FTC NPs compared to pure drug. OPT-FTC NPs showed 2.325 fold increase in the values of FTC concentrations in liver. The OPT-FTC NPs was found to be quite stable during 6 months of study period. Hence, the developed OPT-FTC NPs can be used as drug carrier for sustained/prolonged drug release and/or to reduce toxic effects.     

Preparation of camptothecin-loaded targeting nanoparticles and their antitumor effects on hepatocellular carcinoma cell line H22

Abstract

Camptothecin (CPT) is an effective anticancer agent against various cancers but the clinical application is limited because of its poor water solubility, low bioavailability and severe toxic side effects. The aim of the present study was to evaluate the feasibility of using targeted NPs as a high-performance CPT delivery system that targets liver cancer cells through intravenous (i.v.) administration route. CPT was incorporated into biotin-F127-PLA or F127-PLA polymeric nanoparticles (NPs) by a dialysis method. The preparation of the targeting NPs was performed by conjugating biotin-F127-PLA NPs with anti-3A5 antibody. The antitumor effect of the CPT-loaded nanoparticles against H22 cells in vitro was determined using an MTT assay. Tissue distribution and tumor inhibition in vivo were also evaluated. Survivin mRNA expression was assessed by real-time polymerase chain reaction. Results showed that the targeted CPT NPs exhibited regular spherical shapes with a mean diameter of approximately 180?nm. In vitro release of the targeted CPT NPs exhibited an initial burst (40%) within 12?h, followed by a slow release. Cytotoxicity test against H22 cells indicated that the targeted CPT NPs exerted significant antitumor effects. Compared with free CPT and non-targeted CPT NPs, the targeted CPT NPs showed superior inhibition ratio against tumor in vivo, which may be associated with reduced survivin mRNA expression. The results suggested that the new targeted CPT NPs may be a promising injectable delivery system for cancer therapy.     

Brain-targeted delivery of doxorubicin using glutathione-coated nanoparticles for brain cancers

Abstract

Objectives: To prepare and characterize in vitro a novel brain-targeted delivery of doxorubicin using glutathione-coated nanoparticles (NPs) for the treatment of brain cancer.

Methods: Doxorubicin-loaded NPs were prepared by the nanoprecipitation method using PLGA-COOH (dl-lactide-co-glycolide). The NPs were coated with a glutathione-PEG conjugate (PEG-GSH) in order to target delivery to the brain. The NPs were characterized via in vitro studies to determine particle size, drug release, cellular uptake, immunofluorescence study, cytotoxic assay, and in vitro blood–brain barrier (BBB) assay.

Results: The NPs showed a particle size suitable for BBB permeation (particle size around 200?nm). The in vitro release profile of the NPs exhibited no initial burst release and showed sustained drug release for up to 96?h. The immunofluorescence study showed the glutathione coating does not interfere with the drug release. Furthermore, in vitro BBB Transwell? study showed significantly higher permeation of the doxorubicin-loaded NPs compared with the free doxorubicin solution through the coculture of rat brain endothelial (RBE4) and C6 astrocytoma cells (p?<?0.05).

Conclusions: We conclude that the initial in vitro characterization of the NPs demonstrates potential in delivering doxorubicin to cancer cells with possible future application in targeting brain cancers in vivo.     

Development and evaluation of co-formulated docetaxel and curcumin biodegradable nanoparticles for parenteral administration

Context: Technology for development of biodegradable nanoparticles encapsulating combinations for enhanced efficacy.

Objective: To develop docetaxel (DTX) and curcumin (CRM) co-encapsulated biodegradable nanoparticles for parenteral administration with potential for prolonged release and decreased toxicity.

Materials and methods: Modified emulsion solvent-evaporation technique was employed in the preparation of the nanoparticles optimized by the face centered-central composite design (FC-CCD). The uptake potential was studied in MCF-7 cells, while the toxicity was evaluated by in vitro hemolysis test. In vivo pharmacokinetic was evaluated in male Wistar rats.

Results and discussion: Co-encapsulated nanoparticles were developed of 219?nm size, 0.154 PDI, ?13.74?mV zeta potential and 67.02% entrapment efficiency. Efficient uptake was observed by the nanoparticles in MCF-7 cells with decreased toxicity in comparison with the commercial DTX intravenous injection, Taxotere®. The nanoparticles exhibited biphasic release with initial burst release followed by sustained release for 5 days. The nanoparticles displayed a 4.3-fold increase in AUC (391.10?±?32.94 versus 89.77?±?10.58?μg/ml min) in comparison to Taxotere® with a 6.2-fold increase in MRT (24.78?±?2.36 versus 3.58?±?0.21?h).

Conclusion: The nanoparticles exhibited increased uptake, prolonged in vitro and in vivo release, with decreased toxicity thus exhibiting potential for enhanced efficacy.     

Fabrication of long-acting insulin formulation based on poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanoparticles: preparation,optimization, characterization,and in vitro evaluation

The purpose of this research was the fabrication, statistical optimization, and in vitro characterization of insulin-loaded poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) nanoparticles (INS-PHBV-NPs). Nanopar-ticles were successfully developed by double emulsification solvent evaporation method. The NPs were characterized for particle size, entrapment efficiency (EE%), and polydispersity index (PDI). The NPs also were characterized by scanning electron microscopy (SEM), Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and circular dichroism (CD). The optimum conditions were found to be 1.6% polyvinyl alcohol (PVA), 0.9% of PHBV, and 15?mg/ml of insulin with the aid of the Box–Behnken experimental design results. The optimized NPs showed spherical shape with particle size of 250.21?±?11.37?nm, PDI of 0.12?±?0.01, and with EE% of 90.12?±?2.10%. In vitro drug release pattern followed Korsmeyer–Peppas model and exhibited an initial burst release of 19% with extended drug release of 63.2% from optimized NPs within 27?d. In conclusion, these results suggest that INS-PHBV-NPs could be a promising candidate for designing an injectable sustained release formulation for insulin.     

Surface modification of doxorubicin-loaded nanoparticles based on polydopamine with pH-sensitive property for tumor targeting therapy

One major challenge of current surface modification of nanoparticles is the demand for chemical reactive polymeric layers, such modification is always complicated, inefficient, and may lead the polymer lose the ability to encapsulate drug. To overcome this limitation, we adopted a pH-sensitive platform using polydopamine (PDA) as a way of functionalizing nanoparticles (NPs) surfaces. All this method needed to be just a brief incubation in weak alkaline solution of dopamine, which was simple and applicable to a variety of polymer carriers regardless of their chemical reactivity. We successfully conjugated the doxorubicin (DOX)-PDA-poly (lactic-co-glycolic acid) (PLGA) NPs with two typical surface modifiers: folate (FA) and a peptide (Arg-Gly-Asp, RGD). The DOX-PDA-FA-NPs and DOX-PDA-RGD-NPs (targeting nanoparticles) were characterized by particle size, zeta potential, and surface morphology. They were quite stable in various physiological solutions and exhibited pH-sensitive property in drug release. Compared to DOX-NPs, the targeting nanoparticles possessed an excellent targeting ability against HeLa cells. In addition, the in vivo study demonstrated that targeting nanoparticles achieved a tumor inhibition rate over 70%, meanwhile prominently decreased the side effects of DOX and improve drug distribution in tumors. Our studies indicated that the DOX-PLGA-NPs modified with PDA and various functional ligands are promising nanocarriers for targeting tumor therapy.     

Self-assembled nanoparticles of reduction-sensitive poly (lactic-co-glycolic acid)-conjugated chondroitin sulfate A for doxorubicin delivery: preparation,characterization and evaluation

In this study, reduction-sensitive self-assembled polymer nanoparticles based on poly (lactic-co-glycolic acid) (PLGA) and chondroitin sulfate A (CSA) were developed and characterized. PLGA was conjugated with CSA via a disulfide linkage (PLGA-ss-CSA). The critical micelle concentration (CMC) of PLGA-ss-CSA conjugate is 3.5?µg/mL. The anticancer drug doxorubicin (DOX) was chosen as a model drug, and was effectively encapsulated into the nanoparticles (PLGA-ss-CSA/DOX) with high loading efficiency of 15.1%. The cumulative release of DOX from reduction-sensitive nanoparticles was only 34.8% over 96?h in phosphate buffered saline (PBS, pH 7.4). However, in the presence of 20?mM glutathione-containing PBS environment, DOX release was notably accelerated and almost complete from the reduction-sensitive nanoparticles up to 96?h. Moreover, efficient intracellular DOX release of PLGA-ss-CSA/DOX nanoparticles was confirmed by CLSM assay in A549 cells. In vitro cytotoxicity study showed that the half inhibitory concentrations of PLGA-ss-CSA/DOX nanoparticles and free DOX against A549 cells were 1.141 and 1.825?µg/mL, respectively. Therefore, PLGA-ss-CSA/DOX nanoparticles enhanced the cytotoxicity of DOX in vitro. These results suggested that PLGA-ss-CSA nanoparticles could be a promising carrier for drug delivery.     

Targeted delivery of monoclonal antibody conjugated docetaxel loaded PLGA nanoparticles into EGFR overexpressed lung tumour cells

The aim of this study was to develop anti-EGFR antibody conjugated poly(lactide-co-glycolide) nanoparticles (NPs) to target epidermal growth factor receptor, highly expressed on non-small cell lung cancer cells to improve cytotoxicity and site specificity. Cetuximab was conjugated to docetaxel (DTX) loaded PLGA NPs by known EDC/NHS chemistry and characterised for size, zeta potential, conjugation efficiency and the results were 128.4?±?3.6?nm, –31.0?±?0.8?mV, and 39.77?±?3.4%, respectively. In vitro release study demonstrated sustained release of drug from NPs with 25% release at pH 5.5 after 48?h. In vitro cytotoxicity studies demonstrated higher anti-proliferative activity of NPs than unconjugated NPs. Cell cycle analysis and apoptosis study were performed to evaluate extent of cell arrest at different phases and apoptotic potential for the formulations, respectively. In vivo efficacy study showed significant reduction in tumour growth and so antibody conjugated NPs present a promising active targeting carrier for tumour selective therapeutic treatment.     

Biodegradable intranasal nanoparticulate drug delivery system of risedronate sodium for osteoporosis

Context: Osteoporosis (OP) is the most common metabolic bone disease predominantly found in elderly people. It is associated with reduced bone mineral density, results in a higher probability of fractures, especially of the hip, vertebrae, and distal radius. Worldwide prevalence of OP is considered a serious public health concern.

Objective: The purpose of the present work was to develop and evaluate polymeric nanoparticles (NPs) of risedronate sodium (RIS) for the treatment of OP using intranasal (IN) route in order to reduce peripheral toxic effects.

Materials and methods: Polymeric NPs of RIS were prepared by nanoprecipitation methods. Formulations were developed and evaluated in context to in vitro drug release, ex vivo permeation, in vivo study, and biochemical studies.

Results and discussions: The particles size, entrapment efficiency (EE) (%), and loading capacity (LC) (%) of optimized formulations were found to be 127.84?±?6.33?nm, 52.65?±?5.21, and 10.57?±?1.48, respectively. Release kinetics showed diffusion-controlled, Fickian release pattern. Ex vivo permeation study showed RIS from PLGA-NPs permeated significantly (p?<?0.05) through nasal mucosa. In vivo study showed a marked difference in micro-structure (trabeculae) in bone internal environment. Biochemical estimation of treated group and RIS PLGA indicated a significant recovery (p?<?0.01) as compared with the toxic group.

Conclusion: Polymeric NPs of RIS were prepared successfully using biodegradable polymer (PLGA). Intranasal delivery showed a good result in in vivo study. Thus PLGA-NPs have great potential for delivering the RIS for the treatment and prevention of OP after clinical evaluation in near future.     

Development of biodegradable polymeric implants of RGD-modified PEG-PAMAM-DOX conjugates for long-term intratumoral release

Abstract

Context: The sustained release implants can be directly implanted in tumor site by surgery and are promising for cancer treatment.

Objective: RGD-modified PEGylated polyamidoamine (PAMAM) dendrimer with doxorubicin (DOX) conjugated by acid-sensitive linkage (RGD-PPCD) was a potential conjugate for tumor-targeted therapy. In order to enhance tumor retention ability and long-term effect of drug, we developed the DOX and its conjugate implants using poly(dl-lactic-co-glycolic acid) (PLGA), poly(dl-lactic acid) (PLA) and polyethylene glycol (PEG) as carrier materials.

Methods: The implants were prepared by a simple solvent evaporation method. Different formulations with varying ratios of three polymers were designed, prepared and evaluated on the basis of viscosity, in vitro release and drying time. Furthermore, in vivo biodistribution and antitumor activity of the implants were studied in mice with subcutaneous C6 xenografts.

Results: The optimized formulation was obtained with the 3:1 ratio of PLGA/PLA (w/w) and 1% PEG (wt.%). The drug release behavior of DOX, PPCD and RGD-PPCD implants prepared by the optimized formulation was similar according to the assessment of similarity factor f₂, and the release curves were fell into three phases, including a lag-period, then the second phase which was consistent with zero-order model followed by a plateau. Data of total DOX remained in implants indicated the release were faster in vivo than in vitro. Moreover, intratumoral drug amount of RGD-PPCD implants was the highest 45 days after implantation. Correspondingly, the RGD-PPCD implants exhibited the strongest antitumor activity compared with PPCD and free DOX implants.

Discussion and conclusion: This paper presents an exploratory research on macromolecule-drug conjugates, including RGD-PPCD and PPCD, which have the potential to be developed into long-term effect implants for tumor therapy with high efficiency and low systematic toxicity.     

Induction of an in vitro reversible hypometabolism through chitosan-based nanoparticles

Objective: Chitosan-based nanoparticles (NPs) were prepared to promote intracellular sustained delivery of the synthetic delta opioid D-Ala(2)-D-Leu(5)-enkephalin (DADLE), prolonging peptide activity and inducing a safe and reversible hypometabolic state.

Materials and methods: NPs were prepared by combining ionotropic gelation and ultrasonication treatment. NP uptake studies and the effects of encapsulated DADLE on HeLa cells proliferation were tested by transmission electron microscopy (TEM) analysis, by immuno-fluorescence and immuno-cytochemistry.

Results: DADLE-loaded NPs are produced with suitable characteristics, a satisfactory process yield (55.4%?±?2.4%) and encapsulation efficiency (64.6%?±?2.1%). NPs are effective in inducing a hypometabolic stasis at a 10^?4?M DADLE concentration. Moreover, as seen from the immunofluorescence study, the effect persists through the recovery period (72?h). Indeed, NPs labelled by anti-enkephalin antibody inside cell nucleus reassert that the in vivo release of the peptide can be prolonged with respect to the case of free peptide supply.

Conclusion: The nanoparticulate drug delivery system described seems to be effective in inducing and prolonging a sort of hibernation-like state in the cells.     

Bile acid-conjugated chondroitin sulfate A-based nanoparticles for tumor-targeted anticancer drug delivery

Chondroitin sulfate A-deoxycholic acid (CSA-DOCA)-based nanoparticles (NPs) were produced for tumor-targeted delivery of doxorubicin (DOX). The hydrophobic deoxycholic acid (DOCA) derivative was conjugated to the hydrophilic chondroitin sulfate A (CSA) backbone via amide bond formation, and the structure was confirmed by ¹H-nuclear magnetic resonance (NMR) analysis. Loading the DOX to the CSA-DOCA NPs resulted in NPs with an approximately 230 nm mean diameter, narrow size distribution, negative zeta potential, and relatively high drug encapsulation efficiency (up to 85%). The release of DOX from the NPs exhibited sustained and pH-dependent release profiles. The cellular uptake of DOX from the CSA-DOCA NPs in CD44 receptor-positive human breast adenocarcinoma MDA-MB-231 cells was reduced when co-treated with free CSA, indicating the interaction between CSA and the CD44 receptor. The lower IC₅₀ value of DOX from the CSA-DOCA NPs compared to the DOX solution was also probably due to this interaction. Moreover, the ability of the developed NPs to target tumors could be inferred from the in vivo and ex vivo near-infrared fluorescence (NIRF) imaging results in the MDA-MB-231 tumor-xenografted mouse model. Both passive and active strategies appear to have contributed to the in vivo tumor targetability of the CSA-DOCA NPs. Therefore, these CSA-DOCA NPs could further be developed into a theranostic nanoplatform for CD44 receptor-positive cancers.     

Magnetically triggered drug release from nanoparticles and its applications in anti-tumor treatment

The objective of this study was to describe the magnetic nanoparticle–drug conjugates for improved control of drug delivery and drug release. The widely used anticancer agent Doxorubicin (DOX) was successfully conjugated via amine groups to the carboxylic functional groups coating magnetic nanoparticles (fluidMAG-CMX). Following purification of the nanoparticles, the conjugation of DOX on fluidMAG-CMX was confirmed using FTIR spectroscopy and confocal microscopy. The observed drug loading capacity of DOX was 22.3%. Studies of magnetically triggered release were performed under an oscillating magnetic field (OMF). DOX exhibited a significant release percentage of 70% under an OMF, as compared with the release in enzyme. A magnetic field turn-on and turn-off experiment was also conducted to confirm the control of drug release using this triggered system. In vivo experiments indicated that the tumor-inhibitory rate of CMX–DOX NPs under a magnetic field was higher than the other control groups. According to the toxicity assessments, CMX–DOX NPs were not noticeably toxic to mice at our tested dose.     

Comparative study of kanamycin sulphate microparticles and nanoparticles for intramuscular administration: preparation in vitro release and preliminary in vivo evaluation

Kanamycin sulphate (KS) is a Mycobacterium tuberculosis protein synthesis inhibitor. KS is polycationic, a property responsible for KS poor oral absorption half-life (2.5?h) and rapid renal clearance, which results in serious nephrotoxicity/ototoxicity. The current study aimed to develop KS-loaded PLGA vitamin-E-TPGS microparticles (MPs) and nanoparticles (NPs) to reduce the dosing frequency and dose-related adverse effect. In vitro release was sustained up to 10 days for KS PLGA–TPGS MPs and 13 days for KS PLGA–TPGS NPs in phosphate-buffered saline (PBS) pH 7.4. The in vivo pharmacokinetic test in Wistar rats showed that the AUC_0–∞ of KS PLGA–TPGS NPs (280.58?μg/mL*min) was about 1.62-fold higher than that of KS PLGA–TPGS MPs (172.30?μg/mL*min). Further, in vivo protein-binding assay ascribed 1.20-fold increase in the uptake of KS PLGA–TPGS NPs through the alveolar macrophage (AM). The studies, therefore, could provide another useful tool for successful development of KS MPs and NPs.     

Which one performs better for targeted lung cancer combination therapy: pre- or post-bombesin-decorated nanostructured lipid carriers?

Abstract

Purpose: The co-delivery of gene and drugs has the potential to treat cancer. The aim of this study was to compare post-bombesin decorated nanostructured lipid carriers (NLC) carrying both doxorubicin (DOX) and DNA with pre-bombesin decorated NLC for lung cancer therapy.

Methods: Post-bombesin decorated NLC were prepared by two steps. First, DOX and DNA-loaded NLC (DOX-DNA-NLC) was prepared. Second, Bombesin-NH₂ (BN-NH₂) was added into DOX-DNA-NLC to react with stearic acid-polyethylene glycol-COOH (SA-PEG-COOH) loaded in NLC. Pre-bombesin decorated NLC were prepared by two steps. First, Bombesin (BN)-conjugated ligands were synthesized. Second, DOX and DNA were loaded into BN decorated NLC. Their average size, zeta potential, drug and gene loading were evaluated. NCl-H460 human non-small lung cancer cells (NCl-H460 cells) were used for the testing of in vitro transfection efficiency and in vitro cytotoxicity. In vivo transfection efficiency and anti-tumor effect of NLC were evaluated on mice bearing NCl-H460 cells model.

Results: Post-bombesin decorated NLC has a particle size of 128?nm, DOX encapsulation efficiency (EE) of 85% and DNA EE of 91%. Pre-bombesin decorated NLC has a particle size of 101?nm, DOX EE of 86% and DNA EE of 92%. Post-bombesin decorated NLC displayed more stable and remarkably higher transfection efficiency and better anti-tumor ability than pre-bombesin decorated NLC both in vitro and in vivo.

Conclusion: Post-bombesin decorated NLC could function as better carriers to improve the cell targeting and nuclear targeting ability. The resulting nanomedicine could be a promising active targeting drug/gene therapeutic system for lung cancer therapy.