PosterAbstracts

__________________________________________1. Dimeric synthetic receptor for carbohydraterecognitionM.FernandoBravo,*KalanidhiPalanichamy,SamuelR.Peurifoy, Milan Shlain, Yasir Naeem, Adam B.BraunschweigCUNYAdvancedScienceResearchCenter&Dept.ofChemistry,HunterCollege

By targeting thepyranosides that areprevalent on theglycocalyx, syntheticcarbohydrate receptorscould serve as agents fordisease detection, drugdelivery, or eventherapeutics1. Currently,syntheticlectinsarerarelyused for theseapplicationsbecausetheyprimarily bind only allequatorialglucosidesthatare absent from theglycocalyx.Toaddressthischallenge, we havepreviously reported ahighly flexible syntheticcarbohydrate receptorthatachievedmannoside-specificbindingby relyinguponmultivalentandcooperativebinding modes2. The major drawback of this previousreceptor, however, is that binding has been demonstratedonly in chloroform. Herein we have developed a newpyranosidereceptor,1,(Figure1)thatreliesuponH-bonding,C−H•••π interactions, and conformational flexibility toachieve high binding affinity with C1-methoxy pyranosides.Like natural glycan binding proteins, this receptor bindspyranosidesbyaccessingmultivalentinteractions,andstudiessuggest a new approach towards the biomimetic design ofsynthetic carbohydrate receptors, where conformationalflexibility and promiscuity are considered beneficial. Binding

studiesviaNMRtitrationofthecomplexwillrevealitsaffinitywhichwill have implications tomedicine and increasing ourunderstandingofbiologicalrecognition.__________________________________________2. Strong coupling ofmolecular excitons to localizedsurface plasmons and lattice modes of 2D plasmonicnanoparticlearraysRobertCollison,*JacobTrevino,StephenO'Brien,VinodMenon,JohnLombardiDept. of Chemistry, The City College of New York & CUNYAdvancedScienceResearchCenter

Thin film solar cells are an attractive alternative toconventional crystalline Si cells due to their relatively lightweightandlowercostofproduction.However,onlyafractionofsunlightwillbeabsorbedbymostphotovoltaicmaterialsatmicron and submicron thicknesses unless cell geometry andadditional materials and structures are used to trap theincident light. To address this need, researchers haveemployedplasmonicnanoparticlestoenhancetheefficienciesofthinfilmsolarcellsbyincreasingthepercentageofincidentlight absorbed, an effect that is mediated by the localizedsurface plasmon resonances (LSPRs) of the particles. Inaddition to LSPRs, periodic two dimensional arrays ofnanoparticles also support delocalized, propagatingplasmonic-photonic hybrid modes known as surface latticeresonances (SLRs). Recent research has demonstrated that,like LSPRs, SLRs can interact strongly with the excitons oforganicdyesandphotovoltaicmaterials.Theprimarygoalofthis work is to produce SLR-supporting 2D plasmonicnanoparticle arrays onto which exciton-generatingsupramolecular dye aggregates will be adsorbed, ideallyallowingtheSLRsandtheorganicexcitonstostronglycouple.This ternary (plasmonic-photonic-excitonic) coupling couldservetoenhancetheefficiencyofthin-filmsolarcellsnotonlybeenhancingtheabsorptivityoforganicthinfilmsolarcells,but also by opening up a delocalized mode with excitoniccharacter whose presence increases the effective diffusionlengthsoftheexcitons,therebyfacilitatingthetransportoftheexcitons tosurfacesorcontactsatwhichthechargecarriersmaybeseparatedandcollected.

__________________________________________3. II-VI/III-V Heterovalent Interfaces and NovelApplicationsT.A.Garciac,V.Deligiannakisa,*Y.Kayac,S.Shafiqueb,C.F.Gmachlc,I.L.Kuskovskyb,V.Kartazayeua,S.Gayena,V.Menona,M.C.TamargocaDepartmentofPhysicsCityCollegeofNewYork,bDepartmentof Physics Queens College, cDepartment of Chemistry CityCollege of New York, dDepartment of Electrical EngineeringPrincetonUniversity

IntheMBElabatCCNYwehavebeenfocusingonthegrowth of world class II-VI semiconductors for variousapplications including high efficiency photovoltaics, novelspintronicmaterials,lightemittingdevicesanddetectorsthatspan a wide range of the visible and IR spectrum. III-Vsubstrates are used to achieve high quality II-VI materials.These substrates are prepared in a dedicated III-V chamberpriortoII-VIgrowth.SamplesareshuttledtotheII-VIchamberviaanultra-highvacuumtrack,neverexposingthesurfacetoatmosphere.Thepreparationoftheheterovalentinterfaceisofparamountimportanceandrequiresasequenceofcarefullydesignedsteps.Beingabletotakeadvantageofheterovalentstructuresfortheiruseindevicesprovidesopportunitiesthatcannot be achieved with isovalent ones. However,interdiffusion, charge imbalance, interlayer formation andelectric dipoles are all critical factors that can affect theheterostructure properties.We are exploring the growth ofnewheterostructuresbystudyingtheseeffectsandcontrollingthisinterfaceformationforfuturedevicesandnovelphysics.__________________________________________4. Bi2Se3 Van der Waals Virtual Substrates for II-VIHeterostructuresThor Axtmann Garcia,* Vasilios Deligianakis, CandiceForrester,IdoLevy,andMariaC.TamargoDepartmentofChemistry,TheCityCollegeofNewYork

We report on the growth and characterization ofopticalqualitymultiplequantumwellstructuresofZnxCd1-xSe/ ZnxCdyMg1-x-ySe on an ultra-thin Bi2Se3/CdTe virtualsubstrateonc-planeAl2O3(sapphire).Excellentqualityhighlyorientedfilmsgrownalongthe(111)directionwereachievedasevidencedbyreflectionhighenergyelectrondiffractionandx-raydiffractionstudies.Wealsoobservedroomtemperatureand 77K photoluminescence emissionwith peak energies at77Kof2.407eVandlinewidthsof56meVcomparabletothoseachieved on structures grown on InP. Exfoliation of thestructuresisalsopossibleduetotheVanderWaalsbondingofBi2Se3. Exfoliated (substrate free) films exhibitphotoluminescence emission nearly identical to that of thesupported film. Additionally, contactless electroreflectancemeasurementsshowgoodagreementwithsimulationsofthemultiplequantumwellstructureaswellasevidenceofexcitedstate levels.Theseresultsopennewavenuesofresearchforsubstrateindependentepitaxyandthepossibilityofultra-thinelectronics.__________________________________________5. Elucidating The Crystal Growth Mechanism of

IndomethacinandNifedipineKarishmaA.Gopaul,*AndreBarrella,DanieleMusumeciDept.ofChemistry,YorkCollege

Thedeliveryofpoorlywater-solubledrugsisacrucialproblemforthepharmaceuticalindustry.Approximately80%ofcurrentdrugcandidatesintheR&Dpipelinehavelowwatersolubility and risk to fail due to solubility problems. Severaldrugdeliverysystemshavebeendevelopedinthelastdecadestoincreasethesolubilityand/orthedissolutionrateofpoorlysolubledrugs.Thesesystemsaimtocreateatemporarystateof supersaturation in the GI tract to enhance the drugabsorption.Supersaturatedsolutions,however,areinherentlyunstable,andtheytendtocrystallizeovertimetoreachtheequilibriumsolubility.Therefore,tosuccessfullyenhancetheintestinalabsorptionofpoorly-solubledrugs,adrugdeliverysystemmustnotonlygeneratea stateof supersaturation inthe GI tract, but alsomaintain it for an extended period oftime. Polymeric precipitation inhibitors (PPIs) can delaycrystallization fromsupersaturated solutionsandextend thetimethatthedrugmoleculesspendinsolution.However,theirmechanism of action remains poorly understood and theselectionofpolymericinhibitorsismostlybasedonempiricalcriteria.The proposed project aims to gain a better insight of themechanismsbywhichpolymers inhibit thecrystalgrowthofpharmaceuticaldrugsfromsolution.Thefirststeptowardsthisgoalistounderstand,atthemolecularlevel,thecrystalgrowthmechanisms of poorly soluble drugs. In this work, singlecrystalsofIndometacin(IMC),ananti-inflammatorydrug,andNifedipine (NIF), a calcium-channel blocker, were obtainedfrom solution and were characterized by using DifferentialScanning Calorimetry (DSC) and RAMAN microscopy. X-RaySingleCrystalDiffractionwasusedtodeterminetheunitcelland to assign the Miller indices of the crystal faces. Thisanalysis combined with the X-ray structures of crystals wasused to determine the fastest growing face and the mainintermolecular interactions involved in the crystal growth.Preliminary atomic force microscopy (AFM) images of IMCcrystal surface in under-saturated solution showed that thecrystaldissolvedformingpitsthatresemblethemacroscopiccrystals. Future studies will aim to measure by AFM thekineticsofdissolutionandgrowthofthecrystalsobtainedinthiswork.Theresultswillprovidequantitativeandqualitativeinformationregardingthepolymer-crystalsurfaceinteractionsandwillhelptoelucidatesomeofthemechanismsbywhichpolymersstabilizesupersaturatedsolutionsofpoorly-solubledrugs.__________________________________________6.SurfaceEnhancedRamanScatteringonPhotoetchedGaNNanowiresAbedHaddad,*JanWeheyr,JohnLombardiDepartmentofChemistry,TheCityCollegeofNewYork

In thiswork,we examine surface enhanced RamanScattering (SERS) on photoetched gallium nitride (GaN)nanowires using of 4-mercaptopyridine (4-MPy) as probemolecule. Nanowires were formed by photoetching GaNgrownviametal-organicchemicalvapordeposition(MOCVD)using potassium peroxydisulphate and potassium hydroxide

solution (K2S2O8¬¬-KOH) under UV exposure. The processresulted in uniform bundles of nanowires with remarkablehomogeneity in distribution across the surface. In the SERSspectrum,largeenhancementstothea1,b1,andb2¬modesareseenusinganexcitationwavelengthof488nm(2.54eV).An enhancement factor (EF) of 2.3 × 106 is observed,comparabletotheoneobtainedwithsilvernanoparticles.Wepropose that is due to: 1) proximity of the excitationwavelength to the energy required to incite transitionsbetweenthevalenceband(VB)ofGaNandlowestunoccupiedmolecularorbital(LUMO)of4-MPY;2)sizeablecontributionsfrom small feedgap "hotspots" that create strongelectromagneticfieldenhancementbetweenwiretips.__________________________________________7.SupramolecularLightHarvestingThinFilmsAndrewLevine,*CharlesKolodziej,Wei-ChunLin,BradenCamargo, Mehroz Ahmed, Clemens Burda, Adam B.BraunschweigCUNYAdvancedScienceResearchCenter&Dept.ofChemistry,HunterCollege

Organicmaterialsareincreasinglyexploredasactivecomponents in electronic, energy harvesting, and sensingapplications. Inthesesystemsnewoptoelectronicpropertiesemergefromtheinteractionsofelectrondonorandacceptorpolymers.1 However, the inability to control the donor-acceptor interface limitskeyfiguresofmerit,suchaschargeseparationandcollectionefficiency.Analternateapproachtoaddressingthischallengeinvolvesassemblingsmallmoleculardonor and acceptor compounds into precisely orderedsuperstructures via specific noncovalent bonding.2 To thisend, we have created a library composed ofdiketopyrrolopyrrole (DPP) donors and perylene bisdiimide(PDI) acceptors that assemble into hierarchicalsuperstructuresthatundergophotoinducedchargeseparationfollowing supramolecular organization. From the ability tochemicallymodifymolecularcomponentsanddonor-acceptorpairings,wehaveestablished systematically the relationshipbetween donor-acceptor molecular structure, frontiermolecularorbitals,morphology,andemergentphotophysics.Understanding of these supramolecular systems allows fortheir direct integration into electronic devices, such as solarcells,transistors,andsensors.__________________________________________8.NanopatterningofBiomaterialsbyThermochemicalNanolithographyXiangyuLiu,*ElisaRiedoCUNYAdvanced ScienceResearchCenter&Dept. of Physics,CityCollegeofNewYork

The adhesive and topographical features rangingfromnano-meterstomicrometersontheextracellularmatrix(ECM) serve the significant role of interacting with variousindividual cell and profoundly impact their complexmulticellular behaviors. Therefore, controlling the surfacechemistryandnano-ormicrosized topographyonECM isofgreatimportanceincellbiologyandtissueengineering.Inthiswork,aminepatternsonbiopolymersurfacewasachievedbylocal thermochemical reaction induced by a commercial

scanning probe lithography-based technique—NanoFrazor.AminepatternwithdensitygradientwasvisualizedbyusingConfocal FluorescentMicroscope. Current results suggestedthatthedensityofexposedaminegroupwillpeakatcertainpatterningtemperature.Toimprovethebindingspecificityoffluorescence dyes and biochemicals, a block containingsulfobetainegroupswasaddedtothebiopolymerbackboneasanti-fouling agent. In the future, the polymer films withsulfobetainegroupswillbepatternedandbindingspecificitywillbecomparedbyusingfluorescencedyesandenzymes.__________________________________________9.EpitaxialAl/InAsJosephsonJunctionsWilliamMayer,*AaronSomoroff,JoesphYuan,KaushiniWickramasinghe,JavadShabaniDepartmentofPhysics,TheCityCollegeofNewYork__________________________________________10. Nanoscopic Investigations of Self-AssembledSupramolecular Light Harvesting Nanotubes andSemiconductorQuantumDotsKaraNg,*C.W.Leishman,N.Visaveliya,N.Yehya,D.M.EiseleDepartmentofChemistry,TheCityCollegeofNewYork

Self-assembled quasi one-dimensional (quasi-1D)nanostructures of π-conjugated molecules exhibit uniqueoptoelectronicproperties,includingsharpexcitontransitions,large oscillator strengths, and high exciton mobility andphotoconductivity,andinorganicsemiconductornanocrystalssimilarly exhibit distinct non-linear optical properties. Thus,theintegrationoftheseorganicandinorganicnanomaterialsoffers the possibility of developing new photonic andoptoelectronic devices. However, to control such complexmaterialsystemsitisessentialtounderstandhowtheirvariousparts interact, and whether these interactions result incoherently shared excited states or in diffusive energytransportbetweenthem.Here,weutilizenear-fieldscanningoptical microscopy (NSOM) to investigate (1) an artificialmodel system:well-defined, thoroughly characterizedquasi-1D light-harvesting nanotubes (LHNTs) self-assembled fromcyanine dye molecules, and (2) cadmium selenide colloidalquantumdots(CdSeQDs).Thenanostructureswere isolatedfrom solution and immobilized on a solid substratewithoutaltering their supramolecular structures, then simultaneoustopographicalandopticalimageswereobtainedforindividualLHNTs and for single CdSe QDs. These results lay thegroundwork for future NSOM investigations of nanoscaleexcitationenergytransferinsupramolecularaggregatesandofresonance coupling in hybrid organic/inorganicnanostructures.__________________________________________11. Room-temperature quantum emitter arrays inhexagonalboronnitrideNicholas Proscia,* Zav Shoton,Harishankar Jayakumar,MichaelDollar,PrithviReddy,MarcusDoherty,AudriusAlkauskas,CarlosA.Meriles,VinodM.MenonDept.ofPhysics,TheCityCollegeofNewYork

Defects in hBN have recently been shown to be anarrow linewidth, room temperature singlephotonemitters(SPE)[1].Whiletheexactnatureofthedefectisstillunclear,the narrow linewidth, room temperature operation andspectral tunabilitymake these emitters highly attractive forquantumtechnologies.Despite theseadvantages,difficultiesin precise control over defect formationboth spectrally andspatially [2–5]makes integration into nano-photonic opticaldevices a non-trivial technological hurdle. Here, we addressthesechallengesbydemonstratingnanoscalespatialcontrolofemitter formation in hBN. The hBN exhibits preferentialquantum emission highly localized to the pillar locations. Inaddition, we find the zero phonon lines (ZPLs) spectrallyclusteredwithin~290meVcenteredat580nm.ThesefindingspavethewayfordeviceintegrationofdefectstatesinhBNinquantumopticalsystemsandoffersameanstorealizerobuston-demand deterministic room temperature quantumemitters.__________________________________________12. MMP-9 responsive peptide nanocarriers fortargeteddeliveryofmetallodrugsJiyeSon,*MariaContel,andReinUlijnCUNYAdvancedScienceResearchCenterandBrooklynCollege

Drugssuchas,cis-platin,oxaliplatin,andcarboplatinhavelimitationsincludingpoorsolubility,quickclearance,lackof selectivity, and limited therapeutic activity. Theselimitations can be addressed by peptide nanotechnology,whichofferuniquedesignspacefordevelopingsaferandmoreeffectivemedicines. Herewe report on the development ofpeptide nanocarriers that targetmatrixmetalloproteinase-9(MMP-9)andusehighlyactiveunconventionalmetallodrugsasthepayloads.Theup-regulationandtherolesofMMPshavebeen associated with cancer invasion and metastasis.Therefore,MMP-9isasuitablecancerspecificbio-targetandthe enzyme action can be exploited to produce a desirableresponse in the peptide nanocarriers: 1) formation of fibersthat stay localized near the cancer cells and 2) site specificrelease of payloads. Scheme 1 shows the structures of twometallodrugs synthesized by the Contel group that werecytotoxicinvitroanddisplayedimpressivetumorreductioninvivoinMDA-MB-231andCaki-1cellsandxenografts.Wewillpresentonthecharacterizationofnovelpeptideamphiphileswith tunable MMP-9 cleavage kinetics and desired self-assembly properties, as well as preliminary studies on theentrapment of the metallodrugs. Using unconventionalmetallodrugs that are highly active against MMP-9overexpressingcell linesaspayloads intheMMP-9targetingpeptidenanocarrierswillprovideaminimallyinvasivemethodtokillcancercellsthatareresistanttocurrentchemotherapy.__________________________________________13.4DChemicalNanolithographyD.Valles,*C.Carbonell,AWong,A.BBraunschweigCUNY Advanced Science Research Center and Dept. ofChemistry,HunterCollege

Controlling the organization of biomaterials onsurfaces with nanometer resolution is of paramountimportanceforfundamentalbiological,physical,andmedical

studies, and for the development of optical and electronicdevices.1 State of the art technologies for constructingmaterialscomposedofdelicateorganicandbiologicallyactivematterarebasedprimarilyuponink-jetprinting,pin-printing,which cannot achieve features below 10 microns, whereasconventional photolithography is expensive and destructive.By marrying massively parallel scanning-probe basednanolithography, specifically polymer-pen lithography (PPL)andbeam-penlithography(BPL),withthenewsurfaceorganicchemistry, we have developed approaches for preparingglycanarrays,2functionalizinggraphene,3andcreatingbrushpolymer arrays.4 Recently, combining massively parallelscanning probe nanolithography, microfluidics, and brushpolymer chemistry, we have achieved 4D organicmicromanufacturing, where the four dimensions are the 3Cartesian coordinates(x,y,z)andthefourthisthe chemicalcomposition of eachspotinanarray(Figure1).5 This novelmaterialsmanufacturingapproach could pavethe way towardsmaterials with thechemical andtopological complexitycommon to biologicalinterfaces.Figure 1 The Road to Hyperspace Nanofabrication. Toaccomplish such 4D nanofabrication, it will be necessary toadvance nanolithography surface chemistry and 3Dcharacterization.(1)Carbonell,C.;Braunschweig,A.B.;Acc.Chem.Res.2016,50,190-198.(2)Bian,S.;He,J.;Schesing,K.B.;Braunschweig,A.B.;Small,2012,8,2000-2005.(3)Bian,S.;Scott,A.M.;Cao,Y.;Liang,Y.;Osuna,S.;Houk,K.N.;Braunschweig,A.B.;J.Am.Chem.Soc.,2013,135,9240-9243.(4)Bian,S.;Zieba,S.B.;Morris,W.;Han,X.;Richter,D.C.;Brown,K.A.;Mirkin,C.A.;Braunschweig,A.B.;Chem.Sci.,2014,5,2023-2030.(5)Liu,X.;Zheng,Y.;Peurifoy,S.R.;Kothari,E.;Braunschweig,A.B.;Polym.Chem.,2016,7,3229-3235.__________________________________________14. USING SPORES OF BACILLUS TO CREATEEVAPORATION-DRIVENENGINESHaozhenWang,*XiChenCUNYAdvancedScienceResearchCenterEvaporationisthedominantformofenergytransferinEarth'sclimate.Herewereportevaporation-drivenenginesthatcanpower common tasks like locomotion and electricitygeneration.Theseenginesstartandrunautonomouslywhenplacedatair-waterinterfaces,andoperateaslongastheairisnot saturated. To create these engines, we developedhygroscopy driven artificial muscles (HYDRAs) that exhibitmoisture-drivenhighactuationstrainandenergydensity.Wedesigned device architectures for HYDRA engines thatgeneratesustainedlinearoscillatorymotion(piston-like)androtarymotion (turbine-like) in the presence of evaporation.Usingtheseengines,wedemonstrateanelectricitygenerator

thatrestsonwaterwhileharvestingitsevaporationtopoweralightsource,andaminiaturecar(weighing0.1kg)thatmovesforwardasthewaterinthecarevaporates.__________________________________________15. AFM characterization of Al/InAs for studyingtopologicalsuperconductivityKaushini Wickramasinghe,* Jospeh Yuan, Tri Nguyan,WilliamMayer,JavadShabaniDept.ofPhysics,TheCityCollegeofNewYork__________________________________________16.EpitaxialGrowthofAl(111)onSi(111)substratesJosephYuan,*KaushiniWrickramsinghe,WilliamMayer,NoahReuter,TriNguyen,JavadShabaniDept.ofPhysics,TheCityCollegeofNewYork