Siamo grati per il sostegno finanziario della National Natural Science Foundation (21675112), progetto di chiave del piano di scienza e tecnologia di Pechino Education Commission (KZ201710028027) e programma di Yanjing giovane studioso di Capital Normal University.

<ol>
	<li>Vorkamp, K., Riget, F. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+review+of+new+and+current-use+contaminants+in+the+Arctic+environment:+Evidence+of+long-range+transport+and+indications+of+bioaccumulation.">A review of new and current-use contaminants in the Arctic environment: Evidence of long-range transport and indications of bioaccumulation.</a> Chemosphere. 111, 379-395 (2014).</li><li>Net, S., Sempere, R., Delmont, A., Paluselli, A., Ouddane, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Occurrence,+fate,+behavior+and+ecotoxicological+state+of+phthalates+in+different+environmental+matrices.">Occurrence, fate, behavior and ecotoxicological state of phthalates in different environmental matrices.</a> Environ Sci Technol. 49 (7), 4019-4035 (2015).</li><li>Xie, Q. L., Liu, S. H., Fan, Y. Y., Sun, J. Z., Zhang, X. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+phthalate+esters+in+edible+oils+by+use+of+QuEChERS+coupled+with+ionic-liquid-based+dispersive+liquid-liquid+microextraction+before+high-performance+liquid+chromatography.">Determination of phthalate esters in edible oils by use of QuEChERS coupled with ionic-liquid-based dispersive liquid-liquid microextraction before high-performance liquid chromatography.</a> Anal BioanalChem. 406 (18), 4563-4569 (2014).</li><li>Ierapetritis, I., Lioupis, A., Lampi, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+phthalates+into+vegetable+oils+by+isotopic+dilution+gas+chromatography+mass+spectrometry.">Determination of phthalates into vegetable oils by isotopic dilution gas chromatography mass spectrometry.</a> Food Anal Methods. 7 (7), 1451-1457 (2014).</li><li>Sun, J. Z., He, H., Liu, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+phthalic+acid+esters+in+Chinese+white+spirit+using+dispersive+liquid-liquid+microextraction+coupled+with+sweeping+beta-cyclodextrin-modified+micellar+electrokinetic+chromatography.">Determination of phthalic acid esters in Chinese white spirit using dispersive liquid-liquid microextraction coupled with sweeping beta-cyclodextrin-modified micellar electrokinetic chromatography.</a> J Sep Sci. 37 (13), 1679-1686 (2014).</li><li>Yilmaz, P. K., Ertas, A., Kolak, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Simultaneous+determination+of+seven+phthalic+acid+esters+in+beverages+using+ultrasound+and+vortex-assisted+dispersive+liquid-liquid+microextraction+followed+by+high-performance+liquid+chromatography.">Simultaneous determination of seven phthalic acid esters in beverages using ultrasound and vortex-assisted dispersive liquid-liquid microextraction followed by high-performance liquid chromatography.</a> J Sep Sci. 37 (16), 2111-2117 (2014).</li><li>Sun, R., Zhuang, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+ultrasensitive+gold+nanoparticles+improved+real-time+immuno-PCR+assay+for+detecting+diethyl+phthalate+in+foodstuff+samples.">An ultrasensitive gold nanoparticles improved real-time immuno-PCR assay for detecting diethyl phthalate in foodstuff samples.</a> Anal Biochem. 480, 49-57 (2015).</li><li>Sun, R. Y., Zhuang, H. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+sensitive+heterogeneous+biotin-streptavidin+enzyme-linked+immunosorbent+assay+for+the+determination+of+di-(2-ethylhexyl)phthalate+(DEHP)+in+beverages+using+a+specific+polyclonal+antibody.">A sensitive heterogeneous biotin-streptavidin enzyme-linked immunosorbent assay for the determination of di-(2-ethylhexyl)phthalate (DEHP) in beverages using a specific polyclonal antibody.</a> Anal Methods. 6 (24), 9807-9815 (2014).</li><li>Zhou, L., Lei, Y., Zhang, D., Ahmed, S., Chen, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+ultra-sensitive+monoclonal+antibody-based+enzyme-linked+immunosobent+assay+for+dibutyl+phthalate+in+human+urinary.">An ultra-sensitive monoclonal antibody-based enzyme-linked immunosobent assay for dibutyl phthalate in human urinary.</a> Sci Total Environ. 541, 570-578 (2016).</li><li>Shen, J., Li, Y., Gu, H., Xia, F., Zuo, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+development+of+sandwich+assay+based+on+the+nanobiotechnologies+for+proteins,+nucleic+Acids,+small+Molecules,+and+ions.">Recent development of sandwich assay based on the nanobiotechnologies for proteins, nucleic Acids, small Molecules, and ions.</a> Chem Rev. 114 (15), 7631-7677 (2014).</li><li>Yin, X. -. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+nucleic+acids+for+electrochemical+and+electrochemiluminescent+sensing+applications.">Functional nucleic acids for electrochemical and electrochemiluminescent sensing applications.</a> TrAC, Trends Anal Chem. 33, 81-94 (2012).</li><li>Nguyen, V. -. T., Kwon, Y. S., Gu, M. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Aptamer-based+environmental+biosensors+for+small+molecule+contaminants.">Aptamer-based environmental biosensors for small molecule contaminants.</a> Curr Opin Biotechnol. 45, 15-23 (2017).</li><li>Groher, F., Suess, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+selection+of+antibiotic-binding+aptamers.">In vitro selection of antibiotic-binding aptamers.</a> Methods. 106, 42-50 (2016).</li><li>Yang, K. -. A., Pei, R., Stojanovic, M. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+selection+and+amplification+protocols+for+isolation+of+aptameric+sensors+for+small+molecules.">In vitro selection and amplification protocols for isolation of aptameric sensors for small molecules.</a> Methods. 106, 58-65 (2016).</li><li>Jing, M., Bowser, M. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Methods+for+measuring+aptamer-protein+equilibria:+a+review.">Methods for measuring aptamer-protein equilibria: a review.</a> Anal. Chim. Acta. 686 (1-2), 9-18 (2011).</li><li>Mehta, J., 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=Selection+and+characterization+of+PCB-binding+DNA+aptamers.">Selection and characterization of PCB-binding DNA aptamers.</a> Anal Chem. 84 (3), 1669-1676 (2012).</li><li>Matsumoto, M., Hirata-Koizumi, M., Ema, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Potential+adverse+effects+of+phthalic+acid+esters+on+human+health:+A+review+of+recent+studies+on+reproduction.">Potential adverse effects of phthalic acid esters on human health: A review of recent studies on reproduction.</a> Regul Toxicol Pharm. 50 (1), 37-49 (2008).</li><li>Goodchild, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Conjugates+of+oligonucleotides+and+modified+oligonucleotides:+a+review+of+their+synthesis+and+properties.">Conjugates of oligonucleotides and modified oligonucleotides: a review of their synthesis and properties.</a> Bioconjug Chem. 1 (3), 165-187 (1990).</li><li>Brown, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+brief+history+of+oligonucleotide+synthesis.">A brief history of oligonucleotide synthesis.</a> Protocols for Oligonucleotides and Analogs: Synthesis and Properties. , 1-17 (1993).</li><li>Reese, C. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Oligo-and+poly-nucleotides:+50+years+of+chemical+synthesis.">Oligo-and poly-nucleotides: 50 years of chemical synthesis.</a> Org Biomol Chem. 3 (21), 3851-3868 (2005).</li><li>Sproat, B., Colonna, F., Mullah, B., 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=An+efficient+method+for+the+isolation+and+purification+of+oligoribonucleotides.">An efficient method for the isolation and purification of oligoribonucleotides.</a> Nucleos Nucleot Nucl. 14 (1-2), 255-273 (1995).</li><li>Han, Y., 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=Selection+of+group-specific+phthalic+acid+esters+binding+DNA+aptamers+via+rationally+designed+target+immobilization+and+applications+for+ultrasensitive+and+highly+selective+detection+of+phthalic+acid+esters.">Selection of group-specific phthalic acid esters binding DNA aptamers via rationally designed target immobilization and applications for ultrasensitive and highly selective detection of phthalic acid esters.</a> Anal Chem. 89 (10), 5270-5277 (2017).</li><li>Bartlett, J. M. S., Stirling, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+short+history+of+the+polymerase+chain+reaction.">A short history of the polymerase chain reaction.</a> PCR protocols. , 3-6 (2003).</li><li>Saiki, R. K., Scharf, S., Faloona, 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=Enzymatic+amplification+of+beta-globin+genomic+sequences+and+restriction+site+analysis+for+diagnosis+of+sickle+cell+anemia.">Enzymatic amplification of beta-globin genomic sequences and restriction site analysis for diagnosis of sickle cell anemia.</a> Science. 230, 1350-1354 (1985).</li><li>Albright, L. M., Slatko, B. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Denaturing+polyacrylamide+gel+electrophoresis.">Denaturing polyacrylamide gel electrophoresis.</a> Current Protocols in Nucleic Acid Chemistry. , A. 3B 1-A. 3B 5 (2001).</li><li>Summer, H., Gr&#228;mer, R., Dr&#246;ge, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Denaturing+urea+polyacrylamide+gel+electrophoresis+(Urea+PAGE).">Denaturing urea polyacrylamide gel electrophoresis (Urea PAGE).</a> JoVE. (32), e1485 (2009).</li><li>Jing, M., Bowser, M. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Methods+for+measuring+aptamer-protein+equilibria:+a+review.">Methods for measuring aptamer-protein equilibria: a review.</a> Anal Chim Acta. 686 (1), 9-18 (2011).</li><li>Sharma, T. K., Bruno, J. G., Dhiman, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ABCs+of+DNA+aptamer+and+related+assay+development.">ABCs of DNA aptamer and related assay development.</a> Biotechnol Adv. 35 (2), 275-301 (2017).</li><li>Liu, R., 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=Signaling-probe+displacement+electrochemical+aptamer-based+sensor+(SD-EAB)+for+detection+of+nanomolar+kanamycin+A.">Signaling-probe displacement electrochemical aptamer-based sensor (SD-EAB) for detection of nanomolar kanamycin A.</a> Electrochim Acta. 182, 516-523 (2015).</li><li>Mendonsa, S. D., Bowser, M. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+evolution+of+functional+DNA+using+capillary+electrophoresis.">In vitro evolution of functional DNA using capillary electrophoresis.</a> J Am Chem Soc. 126, 20-21 (2004).</li><li>Lou, X. H., 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=Micromagnetic+selection+of+aptamers+in+microfluidic+channels.">Micromagnetic selection of aptamers in microfluidic channels.</a> Proc Natl Acad Sci USA. 106 (9), 2989-2994 (2009).</li><li>Cho, M., 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=Quantitative+selection+of+DNA+aptamers+through+microfluidic+selection+and+high-throughput+sequencing.">Quantitative selection of DNA aptamers through microfluidic selection and high-throughput sequencing.</a> Proc. Natl. Acad. Sci. U.S.A. 107, 15373-15378 (2010).</li><li>Cho, M., 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=Quantitative+selection+and+parallel+characterization+of+aptamers.">Quantitative selection and parallel characterization of aptamers.</a> Proc Nat Acad Sci USA. 110 (46), 18460-18465 (2013).</li><li>Song, K. -. M., 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=Gold+nanoparticle-based+colorimetric+detection+of+kanamycin+using+a+DNA+aptamer.">Gold nanoparticle-based colorimetric detection of kanamycin using a DNA aptamer.</a> Anal Biochem. 415 (2), 175-181 (2011).</li><li>Yang, Z., Ding, X., Guo, Q., 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=Second+generation+of+signaling-probe+displacement+electrochemical+aptasensor+for+detection+of+picomolar+ampicillin+and+sulfadimethoxine.">Second generation of signaling-probe displacement electrochemical aptasensor for detection of picomolar ampicillin and sulfadimethoxine.</a> Sens Actuators B. 253 (2017), 1129-1136 (2017).</li><li>Lou, X., Zhao, T., Liu, R., Ma, J., Xiao, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Self-assembled+DNA+monolayer+buffered+dynamic+ranges+of+mercuric+electrochemical+sensor.">Self-assembled DNA monolayer buffered dynamic ranges of mercuric electrochemical sensor.</a> Anal Chem. 85 (15), 7574-7580 (2013).</li><li>Zhao, T., 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=Nanoprobe-enhanced,+split+aptamer-based+electrochemical+sandwich+assay+for+ultrasensitive+detection+of+small+molecules.">Nanoprobe-enhanced, split aptamer-based electrochemical sandwich assay for ultrasensitive detection of small molecules.</a> Anal Chem. 87 (15), 7712-7719 (2015).</li><li>Lou, X., He, L. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surface+passivation+using+oligo(ethylene+glycol)+in+ATRP-assisted+DNA+detection.">Surface passivation using oligo(ethylene glycol) in ATRP-assisted DNA detection.</a> Sens Actuators,B. 129 (1), 225-230 (2008).</li></ol>

Gli autori non dichiarano alcun interesse finanziario concorrenti.

Uno dei vantaggi eccezionale di aptameri è che vengono identificati tramite il metodo in vitro SELEX, mentre gli anticorpi sono generati tramite immunoreactions in vivo . Pertanto, è possono selezionare aptameri con specificità di destinazione desiderata in condizioni sperimentali ben progettate, considerando che gli anticorpi sono limitati a condizioni fisiologiche.
Per facilitare la separazione delle sequenze associati da sequenze gratuiti, diversi SELEX modificate recen...

Insieme a rapido sviluppo economico, accelerazione di industrializzazione e costruzione urbana, l'inquinamento ambientale è più grave che mai. Inquinanti ambientali tipici includono ioni di metalli pesanti, tossine, antibiotici, pesticidi, endocrini e inquinanti organici persistenti (pop). Oltre a ioni metallici e le tossine, altri inquinanti sono piccole molecole che molto spesso consistono in una varietà di congeneri. Ad esempio, il pop più tossici includono i policlorobifenili (PCB), idrocarburi policiclici aromatici (IPA), eteri di difenile polibromurati (PBDE), policloro dibenzo-p-diossine (PCDD), difenili policlorodibenzofurani (PCDF) e ftalico esteri dell'acido (PAEs)1,2, che tutti sono costituiti da numerosi congeneri. Rilevamento di piccola molecola è stata eseguita principalmente da tecniche basate sulla spettrometria di massa/cromatografia a causa della loro diversità di applicazioni3,4,5,6. Per i rilevamenti in loco, metodi basati su anticorpi sono stati recentemente sviluppati7,8,9. Tuttavia, poiché questi metodi sono altamente specifici per un certo congenere, prove multiple devono essere eseguite. Che cosa è più grave è che i romanzo congeneri crescono così in fretta che loro gli anticorpi non possono essere generati nel tempo. Pertanto, lo sviluppo di biosensori di gruppo-specifici per monitorare i livelli totali di tutti i congeneri in un test può fornire una preziosa metrica per valutare lo stato di inquinamento ambientale.
Recentemente, l'acido nucleico aptameri sono stati ampiamente applicati come elementi di riconoscimento in varie piattaforme di biosensori grazie alla loro capacità di riconoscere un'ampia varietà di obiettivi, di ioni e piccole molecole di proteine e cellule10,11 ,12. Aptameri sono identificati attraverso un metodo in vitro chiamato evoluzione sistematica di ligandi di arricchimento esponenziale (SELEX)13,14. SELEX si inizia con la libreria di oligonucleotide sintetico casuale singolo filamento, che contiene circa 1014-1015 sequenze. La dimensione della biblioteca casuale garantisce la diversità delle strutture candidato RNA o DNA. Il processo SELEX tipico è costituito da più cicli di arricchimento fino a quando la libreria viene arricchita in sequenze con alta affinità e specificità per la destinazione. La piscina arricchita finale è quindi sequenziata, e le costanti di dissociazione (Kd) e la selettività contro potenziali sostanze interferenti sono determinati da diverse tecniche quali filtrano vincolanti, cromatografia di affinità, superficie risonanza plasmonica (SPR), ecc. 15
A causa della solubilità in acqua estremamente povera e la mancanza di gruppi funzionali per immobilizzazione superficiale, la selezione di aptamero di POPs è teoricamente difficile. Progressi significativi per SELEX hanno velocizzato la scoperta di aptameri. Tuttavia, la selezione di gruppo-specifici aptameri per POPs non è stato ancora segnalata. Finora, solo il PCB-associazione DNA aptameri con alta specificità per un certo congenere sono stati individuati16. PAEs sono utilizzati principalmente in materiali di cloruro di polivinile, cloruro di polivinile il passaggio da una plastica dura a una plastica elastica, agendo quindi come un plastificante. Alcuni PAEs sono stati identificati come interferenti endocrini, può causare gravi danni alla funzionalità epatica e renale, ridurre la motilità degli spermatozoi maschili e può provocare morfologia anormale dello sperma e cancro testicolare17. Composto - né aptameri PAE-associazione gruppo-specifici sono stati segnalati.
L'obiettivo di questo lavoro è quello di fornire un protocollo rappresentativo per la selezione di aptameri di DNA specifico del gruppo a altamente idrofobi piccole molecole quali PAEs, un gruppo rappresentativo di POPs. Inoltre dimostriamo l'applicazione dell'aptamero selezionato per il rilevamento di inquinamento ambientale. Questo protocollo fornisce indicazioni e spunti per la scoperta di aptamero di altre piccole molecole idrofobiche.

<table>
	<tbody>
		<tr>
			<td>UV-2550</td>
			<td>Shimadzu,Japan</td>
			<td></td>
			<td>protocol, section 3.8.2</td>
		</tr>
		<tr>
			<td>DNA Engnine Thermal cycler,PTC0200</td>
			<td>BIO-RAD</td>
			<td></td>
			<td>section 3.5.1.2 and 3.5.2</td>
		</tr>
		<tr>
			<td>C1000 Touch</td>
			<td>BIO-RAD</td>
			<td></td>
			<td>section 5.3.6 and 6.3</td>
		</tr>
		<tr>
			<td>VMP3 multichannel potentiostat</td>
			<td>Bio-Logic Science, Claix, France</td>
			<td></td>
			<td>section 7.4,7.8 and 7.11</td>
		</tr>
		<tr>
			<td>Epoxy-activated Sepharose 6B</td>
			<td>GE Healthcare (Piscataway, NJ, USA)</td>
			<td>10220020</td>
			<td>argarose beads, section 2.3 and 3.3</td>
		</tr>
		<tr>
			<td>Dynabeads M-270 carboxylic acid magnetic beads</td>
			<td>Invitrogen, USA</td>
			<td>420420</td>
			<td>magnetic beads,section 5.2. and 5.3</td>
		</tr>
		<tr>
			<td>Premix Taq Hot Start Version</td>
			<td>Takara,Dalian,China</td>
			<td>R028A</td>
			<td>polymerase, section 3.5.1.1</td>
		</tr>
		<tr>
			<td>PARAFILM Sealing Membrane</td>
			<td>Bemis, USA</td>
			<td>PM-996</td>
			<td>section 3.6.5</td>
		</tr>
		<tr>
			<td>Lambda Exonuclease</td>
			<td>Invitrogen, USA</td>
			<td>EN0561</td>
			<td>section3.7.1.2.The 10 &#215; reaction buffer is provided along with &#955; exonuclease by the provider.</td>
		</tr>
		<tr>
			<td>Dr. GenTLE 
			Precipitation Carrier</td>
			<td>Takara,Dalian,China</td>
			<td>9094</td>
			<td>section 3.6.2 and 3.8.1</td>
		</tr>
		<tr>
			<td>UNIQ-10 PAGE DNA recovery kit</td>
			<td>Sangon Biotech (Shanghai)</td>
			<td>B511135</td>
			<td>section 4.2</td>
		</tr>
		<tr>
			<td>SYBR Gold nucleic acid gel stain</td>
			<td>Invitrogen, USA</td>
			<td>1811838</td>
			<td>nucelic acid stain dye, section 3.5.1.5</td>
		</tr>
		<tr>
			<td>SYBR Premix Ex Taq II</td>
			<td>Takara,Dalian,China</td>
			<td>RR820A</td>
			<td>polymerase mix contaning polymerase and dNTPs, section 5.3.5</td>
		</tr>
		<tr>
			<td>2-(N-Morpholino)ethanesulfonic acid (MES)</td>
			<td>Sigma-Aldrich</td>
			<td>CAS: 1132-61-2</td>
			<td>section 5.2.1</td>
		</tr>
		<tr>
			<td>1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC)</td>
			<td>Invitrogen, USA</td>
			<td>CAS: 25952-53-8</td>
			<td>section 5.2.2</td>
		</tr>
		<tr>
			<td>N-hydroxysuccinimide (NHS)</td>
			<td>Sigma-Aldrich</td>
			<td>6066-82-6</td>
			<td>section 5.2.3</td>
		</tr>
		<tr>
			<td>mercaptohexanol (MCH)</td>
			<td>Sigma-Aldrich</td>
			<td>CAS: 1633-78-9</td>
			<td>section 7.7</td>
		</tr>
		<tr>
			<td>Gold electrode</td>
			<td>Shanghai Chenhua</td>
			<td>CHI101</td>
			<td>section 7.4. - 7.11</td>
		</tr>
		<tr>
			<td>tris(2-carboxyethyl) phosphine hydrochloride (TCEP)</td>
			<td>Sigma-Aldrich</td>
			<td>CAS: 51805-45-9</td>
			<td>section 7.5</td>
		</tr>
		<tr>
			<td>O-(2-Mercaptoethyl)-O&#39;-methyl-hexa-(ethylene glycol)</td>
			<td>Sigma-Aldrich</td>
			<td>CAS: 651042-82-9</td>
			<td>section 7.7</td>
		</tr>
		<tr>
			<td>diethylhexyl phthalate (DEHP)</td>
			<td>National Institute of Metrology, China</td>
			<td>CAS: 117-81-7</td>
			<td>section 7.11</td>
		</tr>
		<tr>
			<td>Tween 20</td>
			<td>Sigma-Aldrich</td>
			<td>CAS: 9005-64-5</td>
			<td>polyoxyethy-lene(20) sorbaitan monolaurate</td>
		</tr>
		<tr>
			<td>Triton X-100</td>
			<td>Sigma-Aldrich</td>
			<td>CAS: 9002-93-1</td>
			<td>non-ionic surface active agent</td>
		</tr>
		<tr>
			<td>PBS</td>
			<td>Sigma-Aldrich</td>
			<td>P5368</td>
			<td>10 mM phosphate buffer containing 1 M NaCl, pH 7.4</td>
		</tr>
	</tbody>
</table>

phthalic acid ester-binding dna aptamer selection, characterization, and application to an electrochemical aptasensor

Acido ftalico esteri (PAEs) sonouno dei principali gruppi di inquinanti organici persistenti. La rilevazione di gruppo-specifica del PAEs altamente è voluta a causa la rapida crescita dei congeneri. Aptameri di DNA sono state applicate sempre più come elementi di riconoscimento su piattaforme di biosensore, ma selezionando aptameri verso obiettivi altamente idrofobo piccola molecola, come PAEs, sono segnalata raramente. Questo lavoro descrive un metodo basato su tallone progettato per selezionare aptameri di DNA specifico del gruppo di PAEs. Il gruppo amminico funzionalizzati ftalato di dibutile (DBP-NH2) come la destinazione di ancoraggio è stata sintetizzata e immobilizzata le perline di agarosio epossi-attivato, consentendo la visualizzazione del gruppo estere ftalico alla superficie della matrice immobilizzazione, e pertanto la selezione dei leganti specifici del gruppo. Abbiamo determinato le costanti di dissociazione dei candidati aptamero da reazione a catena quantitativa polimerizzazione accoppiato con separazione magnetica. La relativa affinità e selettività di aptameri per altri PAEs sono stati determinati mediante le analisi competitive, dove i candidati aptamero pre-sono stati limitati al DBP-NH2 allegata biglie magnetiche e rilasciato al supernatante sopra incubazione con il PAEs testata o altri potenziali sostanze interferenti. Prova competitiva è stata applicata perché esso fornito un confronto facile affinità tra PAEs che non aveva nessun gruppi funzionali per immobilizzazione superficiale. Infine, abbiamo dimostrato la realizzazione di un aptasensor elettrochimico e usato per rilevazione ultrasensibile e selettivo di 2-etilesilftalato. Questo protocollo fornisce intuizioni per la scoperta di aptamero di altre piccole molecole idrofobiche.

Abbiamo progettato e sintetizzato il gruppo amminico funzionalizzato dibutilftalato (DBP-NH2) come la destinazione di ancoraggio (Figura 1F). Abbiamo quindi effettuato la selezione aptamero del DNA di PAEs utilizzando DBP-NH2 come destinazione ancoraggio e seguendo il metodo di immobilizzazione-base classica destinazione (Figura 2). In ogni round, un pilota PCR è stata effettuata utilizzando la pagina denat...

Watch this Scientific Journal Video about Phthalic Acid Ester-Binding DNA Aptamer Selection, Characterization, and Application to an Electrochemical Aptasensor at JoVE.com

Phthalic Acid Ester-Binding DNA Aptamer Selection, Characterization, and Application to an Electrochemical Aptasensor

Un protocollo per la selezione in vitro e caratterizzazione di aptameri di DNA specifico del gruppo acido ftalico estere-associazione è presentato. È inclusa anche l'applicazione dell'aptamero selezionato in un aptasensor elettrochimico.

Acido ftalico Ester-associazione DNA aptamero selezione, caratterizzazione e applicazione di un Aptasensor elettrochimica

Phthalic acid esters (PAEs) areone of the major groups of persistent organic pollutants. The group-specific detection of PAEs is highly desired due to the ...

phthalic-acid-ester-binding-dna-aptamer-selection-characterization

Research

JoVE Journal

Chemistry

9.7K Views.  Capital Normal University. Un protocollo per la selezione in vitro e caratterizzazione di aptameri di DNA specifico del gruppo acido ftalico estere-associazione è presentato. È inclusa anche l'applicazione dell'aptamero selezionato in un aptasensor elettrochimico.

Video: Phthalic Acid Ester-Binding DNA Aptamer Selection, Characterization, and Application to an Electrochemical Aptasensor

Folding and Characterization of a Bio-responsive Robot from DNA Origami

The DNA nanorobot is a hollow hexagonal nanometric device, designed to open in response to specific stimuli and present cargo sequestered inside. Both stimuli and cargo can be tailored according to specific needs. Here we describe the DNA nanorobot fabrication protocol, with the use of the DNA origami technique. The procedure initiates by mixing short single-strand DNA staples into a stock mixture which is then added to a long, circular, single-strand DNA scaffold in presence of a folding buffer. A standard thermo cycler is programmed to gradually lower the mixing reaction temperature to facilitate the staples-to-scaffold annealing, which is the guiding force behind the folding of the nanorobot. Once the 60 hr folding reaction is complete, excess staples are discarded using a centrifugal filter, followed by visualization via agarose-gel electrophoresis (AGE). Finally, successful fabrication of the nanorobot is verified by transmission electron microscopy (TEM), with the use of uranyl-formate as negative stain.

DNA origami is a powerful method for fabricating precise nanoscale objects by programming the self-assembly of DNA molecules. Here we describe a protocol for the folding of a bio-responsive robot from DNA origami, its purification and negative staining for transmission electron microscopic imaging (TEM).

Pieghevole e caratterizzazione di un robot bio-reattiva da origami di DNA

The DNA nanorobot is a hollow hexagonal nanometric device, designed to open in response to specific stimuli and present cargo sequestered inside. Both ...

Ricerca

Chimica

Nucleoside Triphosphates - From Synthesis to Biochemical Characterization

The traditional strategy for the introduction of chemical functionalities is the use of solid-phase synthesis by appending suitably modified phosphoramidite precursors to the nascent chain. However, the conditions used during the synthesis and the restriction to rather short sequences hamper the applicability of this methodology. On the other hand, modified nucleoside triphosphates are activated building blocks that have been employed for the mild introduction of numerous functional groups into nucleic acids, a strategy that paves the way for the use of modified nucleic acids in a wide-ranging palette of practical applications such as functional tagging and generation of ribozymes and DNAzymes. One of the major challenges resides in the intricacy of the methodology leading to the isolation and characterization of these nucleoside analogues.
	
	In this video article, we present a detailed protocol for the synthesis of these modified analogues using phosphorous(III)-based reagents. In addition, the procedure for their biochemical characterization is divulged, with a special emphasis on primer extension reactions and TdT tailing polymerization. This detailed protocol will be of use for the crafting of modified dNTPs and their further use in chemical biology.

The protocol described herein aims to explain and abridge the numerous obstacles in the way of the intricate route leading to modified nucleoside triphosphates. Consequently, this protocol facilitates both the synthesis of these activated building-blocks and their availability for practical applications.

Nucleosidi trifosfati - Dalla sintesi di biochimica Caratterizzazione

The  traditional strategy for the introduction of chemical functionalities is the  use of solid-phase synthesis by appending suitably modified ...

An Inverse Analysis Approach to the Characterization of Chemical Transport in Paints

The ability to directly characterize chemical transport and interactions that occur within a material (i.e., subsurface dynamics) is a vital component in understanding contaminant mass transport and the ability to decontaminate materials. If a material is contaminated, over time, the transport of highly toxic chemicals (such as chemical warfare agent species) out of the material can result in vapor exposure or transfer to the skin, which can result in percutaneous exposure to personnel who interact with the material. Due to the high toxicity of chemical warfare agents, the release of trace chemical quantities is of significant concern. Mapping subsurface concentration distribution and transport characteristics of absorbed agents enables exposure hazards to be assessed in untested conditions. Furthermore, these tools can be used to characterize subsurface reaction dynamics to ultimately design improved decontaminants or decontamination procedures. To achieve this goal, an inverse analysis mass transport modeling approach was developed that utilizes time-resolved mass spectroscopy measurements of vapor emission from contaminated paint coatings as the input parameter for calculation of subsurface concentration profiles. Details are provided on sample preparation, including contaminant and material handling, the application of mass spectrometry for the measurement of emitted contaminant vapor, and the implementation of inverse analysis using a physics-based diffusion model to determine transport properties of live chemical warfare agents including distilled mustard (HD) and the nerve agent VX.

In this paper, a procedure for quantifying the mass transport parameters of chemicals in various materials is presented. This process involves employing an inverse-analysis based diffusion model to vapor emission profiles recorded by real-time, mass spectrometry in high vacuum.

Un approccio di analisi inversa per la caratterizzazione dei Trasporti Chemical nelle vernici

The ability to directly characterize chemical transport and interactions that occur within a material (i.e., subsurface dynamics) is a vital component in ...

Dynamic Electrochemical Measurement of Chloride Ions

This protocol describes the dynamic measurement of chloride ions using the transition time of a silver silver chloride (Ag/AgCl) electrode. Silver silver chloride electrode is used extensively for potentiometric measurement of chloride ions concentration in electrolyte. In this measurement, long-term and continuous monitoring is limited due to the inherent drift and the requirement of a stable reference electrode. We utilized the chronopotentiometric approach to minimize drift and avoid the use of a conventional reference electrode. A galvanostatic pulse is applied to an Ag/AgCl electrode which initiates a faradic reaction depleting the Cl&#713; ions near the electrode surface. The transition time, which is the time to completely deplete the ions near the electrode surface, is a function of the ion concentration, given by the Nernst equation. The square root of the transition time is in linear relation to the chloride ion concentration. Drift of the response over two weeks is negligible (59 &#181;M/day) when measuring 1 mM [Cl&#713;]using a current pulse of 10 Am-2. This is a dynamic measurement where the moment of transition time determines the response and thus is independent of the absolute potential. Any metal wire can be used as a pseudo-reference electrode, making this approach feasible for long-term measurement inside concrete structures.

Dynamic measurement of chloride ions is presented. Transition time of an Ag/AgCl electrode, during a chronopotentiometric technique, can give the concentration of chloride ions in electrolyte. This method does not require a stable conventional reference electrode.

Dinamica elettrochimica Misura di cloruro di ioni

This protocol describes the dynamic measurement of chloride ions using the transition time of a silver silver chloride (Ag/AgCl) electrode. Silver silver ...

An Aptamer-based Sensor for Unchelated Gadolinium(III)

A method for determining the presence of unchelated trivalent gadolinium ion (Gd3+) in aqueous solution is demonstrated. Gd3+ is often present in samples of gadolinium-based contrast agents as a result of incomplete reactions between the ligand and the ion, or as a dissociation product. Since the ion is toxic, its detection is of critical importance. Herein, the design and usage of an aptamer-based sensor (Gd-sensor) for Gd3+ are described. The sensor produces a fluorescence change in response to increasing concentrations of the ion, and has a limit of detection in the nanomolar range (~100 nM with a signal-to-noise ratio of 3). The assay may be run in an aqueous buffer at ambient pH (~7 - 7.4) in a 384-well microplate. The sensor is relatively unreactive toward other physiologically relevant metal ions such as sodium, potassium, and calcium ions, although it is not specific for Gd3+ over other trivalent lanthanides such as europium(III) and terbium(III). Nevertheless, the lanthanides are not commonly found in contrast agents or the biological systems, and the sensor may therefore be used to selectively determine unchelated Gd3+ in aqueous conditions.

An Aptamer-based Sensor for Unchelated GadoliniumIII

The use of polydeoxynucleotide (44-mer aptamer) molecules for sensing unchelated gadolinium(III) ion in an aqueous solution is described. The presence of the ion is detected via an increase in the fluorescence emission of the sensor.

Un sensore Aptamero-based per Unchelated gadolinio (III)

A method for determining the presence of unchelated trivalent gadolinium ion (Gd3+) in aqueous solution is demonstrated. Gd3+ is often present in samples ...

Electrochemical Impedance Spectroscopy as a Tool for Electrochemical Rate Constant Estimation

Electrochemical impedance spectroscopy (EIS) was used for advanced characterization of organic electroactive compounds along with cyclic voltammetry (CV). In the case of fast reversible electrochemical processes, current is predominantly affected by the rate of diffusion, which is the slowest and limiting stage. EIS is a powerful technique that allows separate analysis of stages of charge transfer that have different AC frequency response. The capability of the method was used to extract the value of charge transfer resistance, which characterizes the rate of charge exchange on the electrode-solution interface. The application of this technique is broad, from biochemistry up to organic electronics. In this work, we are presenting the method of analysis of organic compounds for optoelectronic applications.

Electrochemical impedance spectroscopy (EIS) of species that undergo reversible oxidation or reduction in solution was used for determination of rate constants of oxidation or reduction.

Spettroscopia di impedenza elettrochimica come uno strumento per la stima della costante tasso elettrochimica

Electrochemical impedance spectroscopy (EIS) was used for advanced characterization of organic electroactive compounds along with cyclic voltammetry (CV). ...

Time-resolved Photophysical Characterization of Triplet-harvesting Organic Compounds at an Oxygen-free Environment Using an iCCD Camera

Here, we present a sensible method of the acquisition and analysis of time-resolved photoluminescence using an ultrafast iCCD camera. This system enables the acquisition of photoluminescence spectra covering the time regime from nanoseconds up to 0.1 s. This enables us to follow the changes in the intensity (decay) and emission of the spectra over time. Using this method, it is possible to study diverse photophysical phenomena, such as the emission of phosphorescence, and the contributions of prompt and delayed fluorescence in molecules showing thermally activated delayed fluorescence (TADF). Remarkably, all spectra and decays are obtained in a single experiment. This can be done for solids (thin film, powder, crystal) and liquid samples, where the only limitations are the spectral sensitivity of the camera and the excitation wavelength (532 nm, 355 nm, 337 nm, and 266 nm). This technique is, thus, very important when investigating the excited state dynamics in organic emitters for their application in organic light-emitting diodes and other areas where triplet harvesting is of paramount importance. Since triplet states are strongly quenched by oxygen, emitters with efficient TADF luminescence, or those showing room temperature phosphorescence (RTP), must be correctly prepared in order to remove any dissolved oxygen from solutions and films. Otherwise, no long-lived emission will be observed. The method of degassing solid samples as presented in this work is basic and simple, but the degassing of liquid samples creates additional difficulties and is particularly interesting. A method of minimizing solvent loss and changing the sample concentration, while still enabling to remove oxygen in a very efficient and a repeatable manner, is presented in this work.

Here, we present a method of the spectroscopic characterization of organic molecules by means of time-resolved photoluminescence spectroscopy on the nanosecond-to-millisecond timescale in oxygen-free conditions. Methods to efficiently remove oxygen from the samples and, thus, limit luminescence quenching are also described.

Tempo-risolta caratterizzazione fotofisica di tripletto-raccoglitrici composti organici a un utilizzo di ambiente privo di ossigeno un iCCD telecamera

Here, we present a sensible method of the acquisition and analysis of time-resolved photoluminescence using an ultrafast iCCD camera. This system enables ...

An Engineered Split-TET2 Enzyme for Chemical-inducible DNA Hydroxymethylation and Epigenetic Remodeling

DNA methylation is a stable and heritable epigenetic modification in the mammalian genome and is involved in regulating gene expression to control cellular functions. The reversal of DNA methylation, or DNA demethylation, is mediated by the ten-eleven translocation (TET) protein family of dioxygenases. Although it has been widely reported that aberrant DNA methylation and demethylation are associated with developmental defects and cancer, how these epigenetic changes directly contribute to the subsequent alteration in gene expression or disease progression remains unclear, largely owing to the lack of reliable tools to accurately add or remove DNA modifications in the genome at defined temporal and spatial resolution. To overcome this hurdle, we designed a split-TET2 enzyme to enable temporal control of 5-methylcytosine (5mC) oxidation and subsequent remodeling of epigenetic states in mammalian cells by simply adding chemicals. Here, we describe methods for introducing a chemical-inducible epigenome remodeling tool (CiDER), based on an engineered split-TET2 enzyme, into mammalian cells and quantifying the chemical inducible production of 5-hydroxymethylcytosine (5hmC) with immunostaining, flow cytometry or a dot-blot assay. This chemical-inducible epigenome remodeling tool will find broad use in interrogating cellular systems without altering the genetic code, as well as in probing the epigenotype&#8722;phenotype relations in various biological systems.

Detailed protocols for introducing an engineered split-TET2 enzyme (CiDER) into mammalian cells for chemical inducible DNA hydroxymethylation and epigenetic remodeling are presented.

Un enzima Split-TET2 ingegnerizzati per chimica-inducible DNA Hydroxymethylation e rimodellamento epigenetico

DNA methylation is a stable and heritable epigenetic modification in the mammalian genome and is involved in regulating gene expression to control ...

An Electrochemical Cholesteric Liquid Crystalline Device for Quick and Low-Voltage Color Modulation

We demonstrate a method for fabricating a prototype reflective display device that contains cholesteric liquid crystal (LC) as an active component. The cholesteric LC is composed of a nematic LC 4&#39;-pentyloxy-4-cyanobiphenyl (5OCB), redox-responsive chiral dopant (FcD), and a supporting electrolyte 1-ethyl-3-methylimidazolium trifluoromethanesulfonate (EMIm-OTf). The most important component is FcD. This molecule changes its helical twisting power (HTP) value in response to redox reactions. Therefore, in situ electrochemical redox reactions in the LC mixture allow for the device to change its reflection color in response to electrical stimuli. The LC mixture was introduced, by a capillary action, into a sandwich-type ITO glass cell comprising two glass slides with patterned indium tin oxide (ITO) electrodes, one of which was coated with poly(3,4-ethylenedioxythiophene)-co-poly(ethylene glycol) doped with perchlorate (PEDOT+). Upon application of +1.5 V, the reflection color of the device changed from blue (467 nm) to green (485 nm) in 0.4 s. Subsequent application of 0 V made the device recover the original blue color in 2.7 s. This device is characterized by its fastest electrical response and lowest operating voltage among any previously reported cholesteric LC device. This device could pave the way for the development of next generation reflective displays with low energy consumption rates.

A protocol for the fabrication of a reflective cholesteric liquid crystalline display device containing a redox-responsive chiral dopant allowing quick and low-voltage operation is presented.

Un dispositivo cristallino liquido colesterico elettrochimico per la modulazione di colori veloce e bassa tensione

We demonstrate a method for fabricating a prototype reflective display device that contains cholesteric liquid crystal (LC) as an active component. The ...

Electrochemical Roughening of Thin-Film Platinum Macro and Microelectrodes

This protocol demonstrates a method for electrochemical roughening of thin-film platinum electrodes without preferential dissolution at grain boundaries of the metal. Using this method, a crack free, thin-film macroelectrode surface with up to 40 times increase in active surface area was obtained. The roughening is easy to do in a standard electrochemical characterization laboratory and incudes the application of voltage pulses followed by extended application of a reductive voltage in a perchloric acid solution. The protocol includes the chemical and electrochemical preparation of both a macroscale (1.2 mm diameter) and microscale (20 &#181;m diameter) platinum disc electrode surface, roughening the electrode surface and characterizing the effects of surface roughening on electrode active surface area. This electrochemical characterization includes cyclic voltammetry and impedance spectroscopy and is demonstrated for both the macroelectrodes and the microelectrodes. Roughening increases electrode active surface area, decreases electrode impedance, increases platinum charge injection limits to those of titanium nitride electrodes of same geometry and improves substrates for adhesion of electrochemically deposited films.

This protocol demonstrates a method for electrochemical roughening of thin-film platinum electrodes without preferential dissolution at grain boundaries. The electrochemical techniques of cyclic voltammetry and impedance spectroscopy are demonstrated to characterize these electrode surfaces.

Sgrossatura elettrochimica di Thin-Film Platinum Macro e microelettrodi

This protocol demonstrates a method for electrochemical roughening of thin-film platinum electrodes without preferential dissolution at grain boundaries ...