Name: synthesis of aptamer-pei-g-peg modified gold nanoparticles loaded with doxorubicin for targeted drug delivery
Uploaded: 2020-06-23T13:30:00
Description: Watch this Scientific Journal Video about Synthesis of Aptamer-PEI-g-PEG Modified Gold Nanoparticles Loaded with Doxorubicin for Targeted Drug Delivery at JoVE.com

This research was funded by the National Natural Science Foundation of China (31700840); the Key Scientific Research Project of Henan Province (18B430013, 18A150049). This research was supported by the Nanhu Scholars Program for Young Scholars of XYNU. The authors would like to thank bachelor student Zebo Qu from the College of Life Sciences in XYNU for his helpful works. The authors would like to acknowledge the Analysis &#38; Testing Center of XYNU for the use of their equipment.

CAUTION: Make sure to consult all relevant material safety data sheets (MSDS) before using all chemicals. Several of the chemicals used for preparing copolymer and nanoparticles are acutely toxic. Nanoparticles also have potential hazards. Make sure to use all appropriate safety practices and personal protective equipment, including gloves, lab coat, hoods, full-length pants, and close-toed shoes.
1. Synthesis of double-carboxyl polyethylene glycol (CT-PEG)33
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M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gold+nanoparticles+in+delivery+applications.">Gold nanoparticles in delivery applications.</a> Advanced Drug Delivery Reviews. 60 (11), 1307-1315 (2008).</li><li>Vandghanooni, S., Eskandani, M., Barar, J., Omidi, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antisense+LNA-loaded+nanoparticles+of+star-shaped+glucose-core+PCL-PEG+copolymer+for+enhanced+inhibition+of+oncomiR-214+and+nucleolin-mediated+therapy+of+cisplatin-resistant+ovarian+cancer+cells.">Antisense LNA-loaded nanoparticles of star-shaped glucose-core PCL-PEG copolymer for enhanced inhibition of oncomiR-214 and nucleolin-mediated therapy of cisplatin-resistant ovarian cancer cells.</a> International Journal of Pharmaceutics. 573, 118729 (2020).</li><li>Andghanooni, S., Eskandani, M., Barar, J., Omidi, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=AS1411+aptamer-decorated+cisplatin-loaded+poly(lactic-co-glycolic+acid)+nanoparticles+for+targeted+therapy+of+miR-21-inhibited+ovarian+cancer+cells.">AS1411 aptamer-decorated cisplatin-loaded poly(lactic-co-glycolic acid) nanoparticles for targeted therapy of miR-21-inhibited ovarian cancer cells.</a> Nanomedicine. 13 (21), 2729-2758 (2018).</li><li>Palmieri, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+anti-nucleolin+recombinant+immunoagent+for+cancer+therapy.">Human anti-nucleolin recombinant immunoagent for cancer therapy.</a> Proceedings of the National Academy of Sciences of the United States of America. 112 (30), 9418-9423 (2015).</li><li>Pichiorri, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+NCL+targeting+affects+breast+cancer+aggressiveness+through+miRNA+regulation.">In vivo NCL targeting affects breast cancer aggressiveness through miRNA regulation.</a> Journal of Experimental Medicine. 210 (5), 951-968 (2013).</li><li>Hou, S., McCauley, L. 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X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+and+erosion+properties+of+PEG-containing+polyanhydrides.">Synthesis and erosion properties of PEG-containing polyanhydrides.</a> Macromolecular Bioscience. 7 (5), 620-628 (2007).</li><li>Nie, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Injectable+Vaginal+Hydrogels+as+a+Multi-Drug+Carrier+for+Contraception.">Injectable Vaginal Hydrogels as a Multi-Drug Carrier for Contraception.</a> Applied Sciences. 9 (8), 1638 (2019).</li><li>Zou, P., Suo, J., Nie, L., Feng, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Temperature-responsive+biodegradable+star-shaped+block+copolymers+for+vaginal+gels.">Temperature-responsive biodegradable star-shaped block copolymers for vaginal gels.</a> Journal of Materials Chemistry. 22 (13), 6316-6326 (2012).</li><li>Etrych, T., &#352;ubr, V., Laga, R., &#344;&#237;hov&#225;, B., Ulbrich, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polymer+conjugates+of+doxorubicin+bound+through+an+amide+and+hydrazone+bond:+Impact+of+the+carrier+structure+onto+synergistic+action+in+the+treatment+of+solid+tumours.">Polymer conjugates of doxorubicin bound through an amide and hydrazone bond: Impact of the carrier structure onto synergistic action in the treatment of solid tumours.</a> European Journal of Pharmaceutical Sciences. 58, 1-12 (2014).</li><li>Safari, F., Tamaddon, A. 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The 1H NMR spectrum (Figure 2) confirm the successful synthesis of CT-PEG copolymer and PEI-g-PEG copolymer. The molecular weights of PEG and PEI were 1,000 and 1,200, respectively. Additionally, the EDC/NHS catalytic system was used to synthesize PEI-g-PEG copolymer via amide reactions. It should be noted that if the molecular weights of PEG and PEI changed for synthesizing PEI-g-PEG copolymer, then the reaction time and catalytic system needs to be reevaluated. Also, the reactio...

Being the major public health problem worldwide, cancer is widely characterized as having a low cure rate, high recurrence rate, and high mortality rate1,2. Current conventional anti-cancer methods include surgery, chemotherapy, and radiotherapy3, among which chemotherapy is the primary treatment for cancer patients in the clinic4. Clinical used anticancer drugs mainly include paclitaxel (PTX)5 and doxorubicin (DOX)6,7. DOX, an antineoplastic drug, has been broadly applied in clinical chemotherapy, due to the advantages of cancer cytotoxicity and inhibition of cancer cell proliferation8,9. However, DOX causes cardiotoxicity10,11, and the short half-life of DOX restricts its application in the clinic12. Therefore, degradable drug carriers are needed to load DOX and subequently release in a controlled fashion to a targeted area.
Nanoparticles have been widely used in targeted drug delivery systems and have several advantages in cancer treatment (i.e., sizeable surface-to-volume ratio, small size, ability to encapsulate various drugs, and tunable surface chemistry, etc.)13,14,15. In particular, gold nanoparticles (AuNPs) have been widely used in biological and biomedical applications, such as photothermal cancer therapy16,17. The unique properties of AuNPs, such as facile synthesis and general surface functionalization, have excellent prospects in the clinical field of cancer therapy18. Also, AuNPs have been used to identify drug delivery strategies, diagnose tumors, and overcome resistance in many studies19,20.
Notwithstanding, AuNPs need to be further tailored to overcome drug resistance via high local release at tumor lesions through enhanced permeation and retention (EPR), such as the targeting and accessibility properties. Polymer functionalized AuNPs have exhibited unique advantages, such as improved water solubility of hydrophobic anticancer drugs and prolonged circulation time21,22. Various biocompatible polymers have been used for AuNP coatings, such as polyethylene glycol (PEG), polyethyleneimine (PEI), hyaluronic acid, heparin, and xanthan gum. Then the stability, as well as the payload, of AuNPs is improved well23. Specifically, PEI is a highly branched polymer that is composed of many repeating units of primary, secondary, and tertiary amines24. PEI has excellent solubility, low viscosity, and a high degree of functionality, which is suitable for coating on AuNPs.
On the other hand, anti-cancer drugs need to be delivered to cancer cells directly with improved loading efficiency, and with lower toxicity for treating primary and advanced metastatic tumors25. Targeted ligands have great potential for anti-cancer drug targeted delivery systems26. Its selectivity for target molecule binding confers anti-cancer drug targeting specificity and increases drug enrichment in diseased tissues27. More ligands include antibodies, polypeptides, and small molecules. Compared to other ligands, nucleic acid aptamers can be synthesized in vitro and are easy to modify. AS1411 is an unmodified 26 bp phosphodiester oligonucleotide that forms a stable dimeric G-tetramer structure to specifically bind to an overexpressed target nuclear protein receptor on cancer cells28,29,30. AS1411 inhibits the proliferation of many cancer cells but does not affect the growth of healthy cells31,32. As a result, AS1411 has been used to fabricate an ideal targeted drug delivery system.
In this study, a PEI-g-PEG copolymer is synthesized via an amide reaction, then PEI-g-PEG copolymer coated gold nanoparticles (PEI-g-PEG@AuNPs) are fabricated. Additionally, DOX and AS1411 are sequentially linked to the prepared PEI-g-PEG@AuNPs, as shown in Figure 1. This detailed protocol is intended to help researchers avoid many of the common pitfalls associated with the fabrication of new PEI-g-PEG@AuNPs loaded with DOX and AS1411.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>4-Dimethylaminopyridine</td>
			<td>Macklin</td>
			<td>D807273</td>
			<td></td>
		</tr>
		<tr>
			<td>A549 cell</td>
			<td></td>
			<td>ATCC CCL-185TM</td>
			<td></td>
		</tr>
		<tr>
			<td>AS1411</td>
			<td>BBI Life Sciences Corporation</td>
			<td></td>
			<td>5&#39;-d (TTTGGTGGTGGTGGTTGTGGTGGTGGTGG) FL-AS1411 (fluorophore-labeled AS1411)</td>
		</tr>
		<tr>
			<td>Anhydrous Tetrahydrofuran (THF)</td>
			<td>SinoPharm Chemical Reagent Co., Ltd</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Cell counting kit-8 (CCK-8)</td>
			<td>Sigma Aldrich</td>
			<td>96992-500TESTS-F</td>
			<td></td>
		</tr>
		<tr>
			<td>Dichloromethane</td>
			<td>Traditional Chinese medicine</td>
			<td>80047318</td>
			<td></td>
		</tr>
		<tr>
			<td>Diethyl ether (Et2O)</td>
			<td>SinoPharm Chemical Reagent Co., Ltd</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Dimethyl sulfoxide</td>
			<td>Macklin</td>
			<td>D806645</td>
			<td></td>
		</tr>
		<tr>
			<td>Dulbecco&#39;s modified Eagle&#39;s medium (DMEM)</td>
			<td>Sigma Aldrich</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Doxorubicin hydrochloride</td>
			<td>Rhawn</td>
			<td>R017518</td>
			<td></td>
		</tr>
		<tr>
			<td>Ether absolute</td>
			<td>Traditional Chinese medicine</td>
			<td>80059618</td>
			<td></td>
		</tr>
		<tr>
			<td>Field Emission Transmission Electron Microscope</td>
			<td>FEI Company</td>
			<td>Tecnai G2 F 20</td>
			<td></td>
		</tr>
		<tr>
			<td>Gold(III) chloride trihydrate</td>
			<td>Rhawn</td>
			<td>R016035</td>
			<td></td>
		</tr>
		<tr>
			<td>Laser Particle-size Instrument</td>
			<td>Malvern Instruments Ltd</td>
			<td>ZetasizerNanoZS/Masterszer3000E</td>
			<td></td>
		</tr>
		<tr>
			<td>Microplate Reader</td>
			<td>Molecular Devices</td>
			<td>SpectraMax 190</td>
			<td></td>
		</tr>
		<tr>
			<td>N-(3-Dimethylaminopropyl)-N&#39;-ethylcarbodiimide hydrochloride</td>
			<td>Macklin</td>
			<td>N808856</td>
			<td></td>
		</tr>
		<tr>
			<td>N-Hydroxysuccinimide</td>
			<td>Macklin</td>
			<td>H6231</td>
			<td></td>
		</tr>
		<tr>
			<td>NMR software</td>
			<td>Delta 5.2.1</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Nuclear Magnetic Resonance Spectrometer</td>
			<td>JEOL</td>
			<td>JNM-ECZ600R/S3</td>
			<td></td>
		</tr>
		<tr>
			<td>Origin 8.5</td>
			<td>OriginLab</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin</td>
			<td>Sigma Aldrich</td>
			<td>V900929-100ML</td>
			<td></td>
		</tr>
		<tr>
			<td>Phosphate-buffered saline</td>
			<td>Sigma Aldrich</td>
			<td>P4417-100TAB</td>
			<td></td>
		</tr>
		<tr>
			<td>Poly(ethylene glycol)</td>
			<td>Sigma Aldrich</td>
			<td>81188</td>
			<td>BioUltra, average Mn ~ 1000</td>
		</tr>
		<tr>
			<td>Poly (ethyleneimine) solution</td>
			<td>Sigma Aldrich</td>
			<td>482595</td>
			<td>average Mn ~ 1200, 50 wt.% in H2O</td>
		</tr>
		<tr>
			<td>Sodium borohydride, powder</td>
			<td>Acros</td>
			<td>C18930</td>
			<td></td>
		</tr>
		<tr>
			<td>Streptomycin</td>
			<td>Sigma Aldrich</td>
			<td>85886-10ML</td>
			<td></td>
		</tr>
		<tr>
			<td>Succinic anhydride</td>
			<td>Traditional Chinese medicine</td>
			<td>30171826</td>
			<td></td>
		</tr>
		<tr>
			<td>Tetrahydrofuran</td>
			<td>Traditional Chinese medicine</td>
			<td>40058161</td>
			<td></td>
		</tr>
		<tr>
			<td>Triethylamine</td>
			<td>Traditional Chinese medicine</td>
			<td>80134318</td>
			<td></td>
		</tr>
		<tr>
			<td>UV/VIS/NIR Spectrometer</td>
			<td>Lambda950</td>
			<td>Lambda950</td>
			<td></td>
		</tr>
		<tr>
			<td>X-ray Photoelectron Spectrometer</td>
			<td>Thermo&#8194;Fisher&#8194;Scientific</td>
			<td>K-ALPHA 0.5EV</td>
			<td></td>
		</tr>
	</tbody>
</table>

synthesis of aptamer-pei-g-peg modified gold nanoparticles loaded with doxorubicin for targeted drug delivery

Due to drug resistance and toxicity in healthy cells, use of doxorubicin (DOX) has been limited in clinical cancer therapy. This protocol describes the designing of poly(ethylenimine) grafted with polyethylene glycol (PEI-g-PEG) copolymer functionalized gold nanoparticles (AuNPs) with loaded aptamer (AS1411) and DOX through amide reactions. AS1411 is specifically bonded with targeted nucleolin receptors on cancer cells so that DOX targets cancer cells instead of healthy cells. First, PEG is carboxylated, then grafted to branched PEI to obtain a PEI-g-PEG copolymer, which is confirmed by 1H NMR analysis. Next, PEI-g-PEG copolymer coated gold nanoparticles (PEI-g-PEG@AuNPs) are synthesized, and DOX and AS1411 are covalently bonded to AuNPs gradually via amide reactions. The diameter of the prepared AS1411-g-DOX-g-PEI-g-PEG@AuNPs is ~39.9 nm, with a zeta potential of -29.3 mV, indicating that the nanoparticles are stable in water and cell medium. Cell cytotoxicity assays show that the newly designed DOX loaded AuNPs are able to kill cancer cells (A549). This synthesis demonstrates the delicate arrangement of PEI-g-PEG copolymers, aptamers, and DOX on AuNPs that are achieved by sequential amide reactions. Such aptamer-PEI-g-PEG functionalized AuNPs provide a promising platform for targeted drug delivery in cancer therapy.

1H NMR spectroscopy was used to confirm the successful synthesis of CT-PEG polymer and PEI-g-PEG copolymers (Figure 2). Figure 2a shows that the methylene proton signal at &#948; = 3.61 ppm and carboxyl proton signal at &#948; = 2.57 ppm confirm the successful synthesis of CT-PEG polymers. Figure 2b shows that the methylene proton signal of PEG at &#948; = 2.6 ppm and proton signal of PEI at <em...

Watch this Scientific Journal Video about Synthesis of Aptamer-PEI-g-PEG Modified Gold Nanoparticles Loaded with Doxorubicin for Targeted Drug Delivery at JoVE.com

Synthesis of Aptamer-PEI-g-PEG Modified Gold Nanoparticles Loaded with Doxorubicin for Targeted Drug Delivery

In this protocol, doxorubicin-loaded AS1411-g-PEI-g-PEG modified gold nanoparticles are synthesized via three-step amide reactions. Then, doxorubicin is loaded and delivered to target cancer cells for cancer therapy.

Due to drug resistance and toxicity in healthy cells, use of doxorubicin (DOX) has been limited in clinical cancer therapy. This protocol describes the ...

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JoVE Journal

Chemistry

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