Cationic carbon quantum dots derived from alginate for gene delivery: One-step synthesis and cellular uptake.

UNLABELLED Carbon quantum dots (CQDs), unlike semiconductor quantum dots, possess fine biocompatibility, excellent upconversion properties, high photostability and low toxicity. Here, we report multifunctional CQDs which were developed using alginate, 3% hydrogen peroxide and double distilled water through a facile, eco-friendly and inexpensive one-step hydrothermal carbonization route. In this reaction, the alginate served as both the carbon source and the cationization agent. The resulting CQDs exhibited strong and stable fluorescence with water-dispersible and positively-charged properties which could serve as an excellent DNA condensation. As non-viral gene vector being used for the first time, the CQDs showed considerably high transfection efficiency (comparable to Lipofectamine2000 and significantly higher than PEI, p<0.05) and negligible toxicity. The photoluminescence properties of CQDs also permitted easy tracking of the cellular-uptake. The findings showed that both caveolae- and clathrin-mediated endocytosis pathways were involved in the internalization process of CQDs/pDNA complexes. Taken together, the alginate-derived photoluminescent CQDs hold great potential in biomedical applications due to their dual role as efficient non-viral gene vectors and bioimaging probes. STATEMENT OF SIGNIFICANCE This manuscript describes a facile and simple one-step hydrothermal carbonization route for preparing optically tunable photoluminescent carbon quantum dots (CQDs) from a novel raw material, alginate. These CQDs enjoy low cytotoxicity, positive zeta potential, excellent ability to condense macromolecular DNA, and most importantly, notably high transfection efficiency. The interesting finding is that the negatively-charged alginate can convert into positively charged CQDs without adding any cationic reagents. The significance of this study is that the cationic carbon quantum dots play dual roles as both non-viral gene vectors and bioimaging probes at the same time, which are most desirable in many fields of applications such as gene therapy, drug delivery, and bioimaging.

[1]  Pavel Zrazhevskiy,et al.  Quantum dot imaging platform for single-cell molecular profiling , 2013, Nature Communications.

[2]  C. Mao,et al.  Fluorescent carbon nanoparticles derived from candle soot. , 2007, Angewandte Chemie.

[3]  L. Arendt-Nielsen,et al.  Effects of colchicine-induced microtubule depolymerization on TRPV4 in rats with chronic compression of the dorsal root ganglion , 2013, Neuroscience Letters.

[4]  Jiangnan Yu,et al.  Angelica sinensis polysaccharide nanoparticles as novel non-viral carriers for gene delivery to mesenchymal stem cells. , 2013, Nanomedicine : nanotechnology, biology, and medicine.

[5]  Hui Huang,et al.  Water soluble carbon nanoparticles: hydrothermal synthesis and excellent photoluminescence properties. , 2011, Colloids and surfaces. B, Biointerfaces.

[6]  Guoqing Zhang,et al.  Intracellular uptake and trafficking of difluoroboron dibenzoylmethane-polylactide nanoparticles in HeLa cells. , 2010, ACS nano.

[7]  Xia Tao,et al.  Fluorescent mesoporous silica nanotubes incorporating CdS quantum dots for controlled release of ibuprofen. , 2009, Acta biomaterialia.

[8]  Wangjing Ma,et al.  Easy synthesis of highly fluorescent carbon quantum dots from gelatin and their luminescent properties and applications , 2013 .

[9]  L. Balan,et al.  Folic acid-conjugated core/shell ZnS:Mn/ZnS quantum dots as targeted probes for two photon fluorescence imaging of cancer cells. , 2011, Acta biomaterialia.

[10]  Jun Li,et al.  Multifunctional Hybrid Nanocarriers Consisting of Supramolecular Polymers and Quantum Dots for Simultaneous Dual Therapeutics Delivery and Cellular Imaging , 2013, Advanced healthcare materials.

[11]  Li Chen,et al.  Study of Polycation-Capped Mn:ZnSe Quantum Dots as a Novel Fluorescent Probe for Living Cells , 2014, Journal of Fluorescence.

[12]  Ruth Duncan,et al.  Endocytosis and intracellular trafficking as gateways for nanomedicine delivery: opportunities and challenges. , 2012, Molecular pharmaceutics.

[13]  J. Yu,et al.  Delivery of a transforming growth factor β-1 plasmid to mesenchymal stem cells via cationized Pleurotus eryngii polysaccharide nanoparticles , 2012, International journal of nanomedicine.

[14]  Mario Schelhaas,et al.  Systematic analysis of endocytosis by cellular perturbations. , 2014, Methods in molecular biology.

[15]  E. Zare,et al.  Nanogel and superparamagnetic nanocomposite based on sodium alginate for sorption of heavy metal ions. , 2014, Carbohydrate polymers.

[16]  Yang Liu,et al.  One-step ultrasonic synthesis of fluorescent N-doped carbon dots from glucose and their visible-light sensitive photocatalytic ability , 2012 .

[17]  T. Kissel,et al.  Cellular uptake mechanism and knockdown activity of siRNA-loaded biodegradable DEAPA-PVA-g-PLGA nanoparticles. , 2012, European journal of pharmaceutics and biopharmaceutics : official journal of Arbeitsgemeinschaft fur Pharmazeutische Verfahrenstechnik e.V.

[18]  Yi Lin,et al.  Electrochemical Tuning of Luminescent Carbon Nanodots: From Preparation to Luminescence Mechanism , 2011, Advanced materials.

[19]  Jiangnan Yu,et al.  Encapsulation of plasmid DNA in calcium phosphate nanoparticles: stem cell uptake and gene transfer efficiency , 2011, International journal of nanomedicine.

[20]  Ying Liu,et al.  Cellular uptake, intracellular trafficking, and cytotoxicity of nanomaterials. , 2011, Small.

[21]  Xia Cao,et al.  Efficient gene delivery to mesenchymal stem cells by an ethylenediamine-modified polysaccharide from mulberry leaves. , 2012, Small.

[22]  Xiang-qun Guo,et al.  Carbon dots with tunable emission, controllable size and their application for sensing hypochlorous acid , 2014 .

[23]  C. Murray,et al.  High-temperature photoluminescence of CdSe/CdS core/shell nanoheterostructures. , 2014, ACS nano.

[24]  D. Maysinger,et al.  Short ligands affect modes of QD uptake and elimination in human cells. , 2011, ACS nano.

[25]  Raimo Hartmann,et al.  Multiple internalization pathways of polyelectrolyte multilayer capsules into mammalian cells. , 2013, ACS nano.

[26]  N. Rigby,et al.  Sodium alginate decreases the permeability of intestinal mucus , 2016, Food hydrocolloids.

[27]  H. Okamoto,et al.  Na(+)/H(+) exchanger inhibitor induces vasorelaxation through nitric oxide production in endothelial cells via intracellular acidification-associated Ca2(+) mobilization. , 2013, Vascular pharmacology.

[28]  K. McCullough,et al.  Alginate-coated chitosan nanogels differentially modulate class-A and class-B CpG-ODN targeting of dendritic cells and intracellular delivery. , 2014, Nanomedicine : nanotechnology, biology, and medicine.

[29]  Li-wei Liu,et al.  Cytotoxicity assessment of functionalized CdSe, CdTe and InP quantum dots in two human cancer cell models. , 2015, Materials science & engineering. C, Materials for biological applications.

[30]  Moon J. Kim,et al.  Photoluminescent carbon nanoparticles produced by confined combustion of aromatic compounds , 2012 .

[31]  Xiaoyan Ma,et al.  Preparation and characteristics of sodium alginate/Na(+)rectorite-g-itaconic acid/acrylamide hydrogel films. , 2014, Carbohydrate polymers.

[32]  E. Giannelis,et al.  Surface functionalized carbogenic quantum dots. , 2008, Small.

[33]  A. Seifalian,et al.  Near-infrared quantum dots for HER2 localization and imaging of cancer cells , 2014, International journal of nanomedicine.

[34]  Ernst Wagner,et al.  The internalization route resulting in successful gene expression depends on both cell line and polyethylenimine polyplex type. , 2006, Molecular therapy : the journal of the American Society of Gene Therapy.

[35]  Hui Huang,et al.  One-step ultrasonic synthesis of water-soluble carbon nanoparticles with excellent photoluminescent properties , 2011 .

[36]  R. Fuchs,et al.  Role of endocytic uptake in transfection efficiency of solid lipid nanoparticles‐based nonviral vectors , 2013, The journal of gene medicine.

[37]  Y. Chau,et al.  Size‐dependent internalisation of folate‐decorated nanoparticles via the pathways of clathrin and caveolae‐mediated endocytosis in ARPE‐19 cells , 2014, The Journal of pharmacy and pharmacology.

[38]  Justin Hanes,et al.  Privileged delivery of polymer nanoparticles to the perinuclear region of live cells via a non-clathrin, non-degradative pathway. , 2007, Biomaterials.

[39]  Zhongfu Wang,et al.  Structural characterization of LbGp1 from the fruits of Lycium barbarum L. , 2014, Food chemistry.

[40]  Mohamed Hajji,et al.  Structural, physicochemical and antioxidant properties of sodium alginate isolated from a Tunisian brown seaweed. , 2015, International journal of biological macromolecules.

[41]  Ki Young Choi,et al.  Effect of injection routes on the biodistribution, clearance, and tumor uptake of carbon dots. , 2013, ACS nano.

[42]  Y. Chi,et al.  Electrochemiluminescence of water-soluble carbon nanocrystals released electrochemically from graphite. , 2009, Journal of the American Chemical Society.

[43]  Lie Ma,et al.  Layer by layer chitosan/alginate coatings on poly(lactide-co-glycolide) nanoparticles for antifouling protection and Folic acid binding to achieve selective cell targeting. , 2010, Journal of colloid and interface science.

[44]  Wei Wang,et al.  Nano-carrier for gene delivery and bioimaging based on carbon dots with PEI-passivation enhanced fluorescence. , 2012, Biomaterials.

[45]  S. Ghosh,et al.  Presence of Amorphous Carbon Nanoparticles in Food Caramels , 2012, Scientific Reports.

[46]  Nancy A Monteiro-Riviere,et al.  Mechanisms of quantum dot nanoparticle cellular uptake. , 2009, Toxicological sciences : an official journal of the Society of Toxicology.

[47]  Jiangnan Yu,et al.  Non‐Viral Co‐Delivery of the Four Yamanaka Factors for Generation of Human Induced Pluripotent Stem Cells via Calcium Phosphate Nanocomposite Particles , 2013 .

[48]  J. Weng,et al.  Study of bilineage differentiation of human-bone-marrow-derived mesenchymal stem cells in oxidized sodium alginate/N-succinyl chitosan hydrogels and synergistic effects of RGD modification and low-intensity pulsed ultrasound. , 2014, Acta biomaterialia.

[49]  I. Oh,et al.  Microwave bottom-up route for size-tunable and switchable photoluminescent graphene quantum dots using acetylacetone: New platform for enzyme-free detection of hydrogen peroxide , 2015 .

[50]  Ya‐Ping Sun,et al.  Carbon dots for multiphoton bioimaging. , 2007, Journal of the American Chemical Society.

[51]  Jiangnan Yu,et al.  Efficient gene delivery to human umbilical cord mesenchymal stem cells by cationized Porphyra yezoensis polysaccharide nanoparticles , 2015, International journal of nanomedicine.

[52]  Chun‐Sing Lee,et al.  A graphene quantum dot photodynamic therapy agent with high singlet oxygen generation , 2014, Nature Communications.

[53]  N. Ingle,et al.  Polymeric nucleic acid vehicles exploit active interorganelle trafficking mechanisms. , 2013, ACS nano.

[54]  Xiaoyun Qin,et al.  Hydrothermal Treatment of Grass: A Low‐Cost, Green Route to Nitrogen‐Doped, Carbon‐Rich, Photoluminescent Polymer Nanodots as an Effective Fluorescent Sensing Platform for Label‐Free Detection of Cu(II) Ions , 2012, Advanced materials.

[55]  Xiaofen Li,et al.  Economical and green synthesis of bagasse-derived fluorescent carbon dots for biomedical applications , 2014, Nanotechnology.

[56]  S. Bhatia,et al.  Probing the Cytotoxicity Of Semiconductor Quantum Dots. , 2004, Nano letters.

[57]  Ming Yan,et al.  Cytotoxicity of CdTe quantum dots in human umbilical vein endothelial cells: the involvement of cellular uptake and induction of pro-apoptotic endoplasmic reticulum stress , 2016, International journal of nanomedicine.

[58]  Y. Kapila,et al.  Cellular Mechanisms in Nanomaterial Internalization, Intracellular Trafficking, and Toxicity , 2014 .

[59]  S. Takeoka,et al.  Enhanced cellular uptake of maleimide-modified liposomes via thiol-mediated transport , 2014, International journal of nanomedicine.

[60]  J. Kong,et al.  Nitrogen-doped carbon dots derived from polyvinyl pyrrolidone and their multicolor cell imaging , 2014, Nanotechnology.

[61]  Kristian Berg,et al.  Cellular uptake of DNA-chitosan nanoparticles: the role of clathrin- and caveolae-mediated pathways. , 2012, International journal of biological macromolecules.

[62]  Xiu‐Ping Yan,et al.  Doped quantum dots for chemo/biosensing and bioimaging. , 2013, Chemical Society reviews.

[63]  J. Dominguez‐Vera,et al.  Quantum Dots Decorated with Magnetic Bionanoparticles , 2008 .

[64]  S. Fagerholm,et al.  Loss of beta2-integrin-mediated cytoskeletal linkage reprograms dendritic cells to a mature migratory phenotype , 2014, Nature Communications.