Yongbo Yang

Covalent attachment of Mn-porphyrin onto doxorubicin-loaded poly(lactic acid) nanoparticles for potential magnetic resonance imaging and pH-sensitive drug delivery

In this paper, theranostic nanoparticles (MnP-DOX NPs) were fabricated by conjugating Mn-porphyrin onto the surface of doxorubicin (DOX)-loaded poly(lactic acid) (PLA) nanoparticles (DOX NPs) for potential T1 magnetic resonance imaging and pH-sensitive drug delivery. An in vitro drug release study showed that the release rate of DOX from MnP-DOX NPs was slow at neutral pH but accelerated significantly in acidic conditions. It was found that MnP-DOX NPs could be easily internalized by HeLa cells and effectively suppressed the growth of HeLa cells and HT-29 cells due to the accelerated drug release in acidic lysosomal compartments. Magnetic resonance imaging (MRI) scanning analysis demonstrated that MnP-DOX NPs had much higher longitudinal relaxivity in water (r1 value of 27.8 mM(-1) s(-1) of Mn(3+)) than Mn-porphyrin (Mn(III)TPPS3NH2; r1 value of 6.70 mM(-1) s(-1) of Mn(3+)), behaving as an excellent contrast agent for T1-weighted MRI both in vitro and in vivo. In summary, such a smart and promising nanoplatform integrates multiple capabilities for effective cancer diagnosis and therapy.

Hyaluronic Acid Modified Hollow Prussian Blue Nanoparticles Loading 10-hydroxycamptothecin for Targeting Thermochemotherapy of Cancer

This paper reported the fabrication of a multifunctional nanoplatform by modifying hollow Prussian blue nanoparticles with hyaluronic acid grafting polyethylene glycol, followed by loading 10-hydroxycamptothecin for tumor-targeted thermochemotherapy. It was found that the surface modification of hollow Prussian blue nanoparticles with hyaluronic acid grafting polyethylene endowed a great colloidal stability, long blood circulation time and the capability for targeting Hela cells over-expressing the CD44 receptor. The obtained nanoagent exhibited efficient photothermal effect and a light triggered and stepwise release behavior of 10-hydroxycamptothecin due to the strong optical absorption in the near-infrared region. The investigations on the body weight change, histological injury and blood biochemical indexes showed that such nanoagent had excellent biocompatibility for medical application. Both in vitro and in vivo experiments proved that the combination of chemotherapy and photothermal therapy through the agent of hyaluronic acid modified Prussian blue nanoparticles loading 10-hydroxycamptothecin could significantly improve the therapeutic efficacy compared with either therapy alone because of a good synergetic effect.

Mn-porphyrin conjugated Au nanoshells encapsulating doxorubicin for potential magnetic resonance imaging and light triggered synergistic therapy of cancer.

A theranostic agent was successfully fabricated by the formation of Au nanoshell around poly(lactic acid) nanoparticles entrapping doxorubicin, followed by linking a Mn-porphyrin derivative on the Au shell surface through polyethylene glycol. The resulted agent exhibited excellent colloidal stability and long blood circulation time due to introducing polyethylene glycol. The grafting Mn-porphyrin onto the nanoparticle surface endowed a greatly improved relaxivity (r1 value of 22.18 mM-1s-1 of Mn3+), favorable for accurate cancer diagnosing and locating the tumor site to guide the external near infrared (NIR) laser irradiation for photothermal ablation of tumors. The in vitro experiments confirmed that the agent exhibited an efficient photohyperthermia and a light triggered and stepwise release behavior of doxorubicin due to the high NIR light absorption coefficient of Au nanoshell. The in vivo experiments showed that the combination of chemotherapy and photothermal therapy through such theranostic agent offered a synergistically improved therapeutic outcome compared with either therapy alone, making it a promising approach for cancer therapy. Therefore, such theranostic agent can be developed as a smart and promising nanosystemplatform that integrates multiple capabilities for both effective contrast enhanced magnetic resonance imaging and synergistic therapy.

Chitosan stabilized Prussian blue nanoparticles for photothermally enhanced gene delivery

The lack of biosafety and insufficient delivery efficiency of gene-carriers are still obstacles to human gene therapy. This paper reported highly biocompatible chitosan (CS) functionalized Prussian blue (PB) nanoparticles (designated as CS/PB NPs) for photocontrollable gene delivery. The ultra-small size (∼3 nm), positive charge and high physiological stability of CS/PB NPs make it suitable to be a nonviral vector. In addition, CS/PB NPs could effectively convert the near infrared (NIR) light into heat due to its strong absorption in the NIR region, assisting the uptake of NPs by cells. Upon NIR light irradiation, CS/PB NPs showed superior gene transfection efficiency, much higher than that of free polyethylenimine (PEI). Both in vitro and in vivo experiments demonstrated that CS/PB NPs had excellent biocompatiblity. This work also encourages further exploration of the CS/PB NPs as a photocontrollable nanovector for combined photothermal and gene therapy.

Hyaluronic Acid Conjugated Magnetic Prussian Blue@Quantum Dot Nanoparticles for Cancer Theranostics

A multifunctional nanotheranostic agent was developed by conjugating both hyaluronic acid and bovine serum albumin coated CuInS2-ZnS quantum dots onto the surface of magnetic Prussian blue nanoparticles. The obtained nanoagent could serve as an efficient contrast agent to simultaneously enhance near infrared (NIR) fluorescence and magnetic resonance (MR) imaging greatly. The coexistence of magnetic core and CD44 ligand hyaluronic acid was found to largely improve the specific uptake of the nanoagent by CD44 overexpressed HeLa cells upon applying an external magnetic field. Both NIR fluorescence and MR imaging in vivo proved high accumulation of the nanoagent at tumor site due to its excellent CD44 receptor/magnetic dual targeting capability. After intravenous injection of the nanoagent and treatment of external magnetic field, the tumor in nude mice was efficiently ablated upon NIR laser irradiation and the tumor growth inhibition was more than 89.95%. Such nanotheranostic agent is of crucial importance for accurately identifying the size and location of the tumor before therapy, monitoring the photothermal treatment procedure in real-time during therapy, assessing the effectiveness after therapy.

Doxorubicin and Indocyanine Green Loaded Hybrid Bicelles for Fluorescence Imaging Guided Synergetic Chemo/Photothermal Therapy

Hybrid bicelles have been demonstrated to have great potential for hydrophobic drug delivery. Herein, we report a near-infrared light-driven, temperature-sensitive hybrid bicelles co-encapsulating hydrophobic doxorubicin (DOX) and indocyanine green (ICG) (DOX/ICG@HBs). Encapsulation of ICG into the lipid bilayer membrane of DOX/ICG@HBs results in higher photostability than free ICG. DOX/ICG@HBs exhibited temperature-regulated drug release behavior and significant photothermal cytotoxicity. After tail vein injection, such discotic nanoparticles of DOX/ICG@HBs were found to accumulate selectively at the tumor site and act as an efficient probe to enhance fluorescence imaging greatly. The in vivo experiments showed that the DOX/ICG@HBs-mediated chemo- and photothermal combination therapy was more cytotoxic to tumor cells than the photothermal treatment or the chemotherapy alone due to the synergistic effect, reducing the occurrence of tumor metastasis. Therefore, DOX/ICG@HBs can act as a powerful nanotheranostic agent for chemo/photothermal therapy of cancer under the guidance of near-infrared fluorescence imaging.

Modulating Drug Release Rate from Partially Silica-Coated Bicellar Nanodisc by Incorporating PEGylated Phospholipid

This article reports an effective method to regulate hydrophobic drug release rate from partially silica-coated bicellar nanodisc generated from proamphiphilic organoalkoxysilane and dihexanoylphosphatidylcholine by introducing different molar percentages of 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-PEG2000 (DSPE-PEG2000) into planar bilayers of hybrid bicelles. It was found that the drug release rate increased with increasing the molar percentages of DSPE-PEG2000, and 57.38%, 69.21%, 78.69%, 81.64%, and 82.23% of hydrophobic doxorubicin was released within 120 h from the nanodics incorporating with 0%, 2.5%, 5%, 10%, and 20% DSPE-PEG2000, respectively. Compared with the non-PEGylated nanodisc and free doxorubicin, the PEGylated nanodiscs showed good biocompatibility, high cellular uptake, and adhesion, as well as high local drug accumulation. In addition, both in vitro and in vivo results demonstrated significantly improved antitumor efficacy of the PEGylated nanodisc than its control groups. Thus, the PEGylated nanodisc with partial silica coating offers a facile and efficient strategy of drug delivery for chemotherapy with improved patient acceptance and compliance.

A near infrared fluorescent/ultrasonic bimodal contrast agent for imaging guided pDNA delivery via ultrasound targeted microbubble destruction

This paper reported the development of a multifunctional contrast agent for near infrared (NIR) fluorescent/ultrasonic bimodal imaging and gene delivery. CuInS2–ZnS alloyed quantum dots (ZCIS QDs) were coated with polyethyleneimine (PEI) to complex plasmid DNA (pDNA), followed by adsorption onto the surface of microbubbles (MBs) generated from the surfactant mixture of Span 60 and Tween 80. It was found that the obtained composite agent of MBs@QDs@PEI/pDNA had excellent capability to enhance both ultrasound and fluorescence imaging. In addition, an in vitro cell experiment showed that pDNA could be released from MBs@QDs@PEI/pDNA and internalized by target HeLa cells to realize a relatively high transfection efficiency by ultrasound-targeted microbubble destruction. Furthermore, the cytotoxicity, immune toxicity and histological evaluation showed that MBs@QDs@PEI/pDNA had a good biocompatibility for medical application. Therefore, such a multifunction agent could operate as a promising platform for targeting gene delivery under the guidance of NIR fluorescent/ultrasonic bimodal imaging.

CuInS2/ZnS Quantum Dots Conjugating Gd(III) Chelates for Near-Infrared Fluorescence and Magnetic Resonance Bimodal Imaging

A bimodal contrast nanoagent was developed by chelating gadolinium ions to 2-[bis[2-[carboxymethyl-[2-oxo-2-(2-sulfanylethyl-amino)ethyl]amino]ethyl]amino]acetic acid (DTDTPA)-modified CuInS2/ZnS quantum dots (QDs). The longitudinal relaxivity (r1) of the resulted QDs@DTDTPA-Gd nanoparticles (NPs) was calculated to be 9.91 mM-1 s-1, which was 2.5 times as high as that of clinically approved Gd-DTPA (3.9 mM-1 s-1). In addition, the in vivo imaging experiments showed that QDs@DTDTPA-Gd NPs could enhance both near-infrared fluorescence and T1-weighted magnetic resonance (MR) imaging of tumor tissue through passive targeting accumulation. Moreover, the high colloidal and fluorescence stabilities and good biocompatibility indicate that QDs@DTDTPA-Gd NPs have a great potential for use as an efficient nanoagent to integrate the extremely high sensitivity of fluorescence imaging to the high resolution of MR imaging. Integration of bimodal detectability in the same agent of QDs@DTDTPA-Gd NPs can avoid extra stress on the blood clearance mechanisms as the administration of multiple dose of agents.

Chitosan Functionalized CuS Nanoparticles Boots Gene Transfection via Photothermal Effect

BACKGROUND The lack of smart and controllable gene vectors with high safety and efficiency is still a main obstruction for clinical applications of gene therapy. Recently, the external physical stimuli, such as near infrared light induced temperature elevation, have been applied to enhance the gene transfection efficiency and specificity. The aim of this paper is to fabricate chitosan functionalized CuS nanoparticles (CuS@CS NPs) with small size and higher biocompatibility for enhanced gene delivery by photothermal effect. METHODS CuS@CS NPs were successfully prepared by simple hydrothermal method. The biocompatibility was detected by MTT method and hymolytic analysis. pEGFP-C1was used as gene model, and its expression efficiency was detected by fluorescence microscopy and flow cytometry to investigate the effect of photothermal effect on the transfection efficiency. RESULTS The CuS@CS NPs around 15 nm were successfully engineered. The modification of CuS nanoparticles with chitosan conduced to higher physiological stability and biocompatibility. The utilization of CuS@CS NPs in combination with external near infrared (NIR) laser irradiation could enhance gene transfection efficiency due to photothermal effect. The gene transfection efficiency of CuS@CS NPs found to increase from 5.05±0.54% (0 min) to 23.47±1.27% (10 min), significantly higher than the free polyethylenimine (18.15±1.03%). CONCLUSION CuS@CS NPs showed great capability to control gene delivery by an external NIR laser irradiation and enhance the gene transfection efficiency and specificity because of convenient preparation, stabilized optical properties, excellent photothermal effect and good biocompatibility. It encourages further exploration of the CuS@CS NPs as a photocontrollable nanovector for combined photothermal and gene therapy, as well as image guided therapy.