Biomedical Engineering Reference
In-Depth Information
stabilize. the. proteins. for. analysis.. Since. then,. understanding. surfactant-protein. interac-
tions. has. become. a. ield. in. itself,. since. the. dynamics. between. micelle. formations,. sur-
factant. structure,. and. protein. stability. are. codependent. and. can. be. strongly. affected. by.
minor. chemical. changes.. Extrapolating. from. this. line. of. thought,. it. is. not. inconceivable.
that. maintaining. protein. stability. and. functionality. will. also. be. an. important. aspect. in.
BSSC.design..Protein.interactions.with.nanoscale.surfaces.of.varying.composition,.surface.
potential,. curvature,. and. size. are. currently. an. area. of. study,. typically. in. the. context. of.
nanotoxicity..It.must.be.noted.that.conformation,.including.coiled.vs..stretched.vs..semi-
coiled,.might.play.a.critical.role.
22.6.3 Quantum Dot Enhancement
Aside. from. stabilizing. protein. structures. through. surface. chemistry,. recent. advances. in.
understanding.and.manipulating.the.unique.quantum.mechanics.of.nanodots.have.been.
applied.to.enhancing.the.capabilities.of.photoactive.proteins..Thus.far,.thin.ilms.of.CdSe/
ZnS.quantum.dots.and.bR.protein.have.exhibited.enhanced.performance.as.a.photoactive.
sensor.device.
55
.Because.the.enhanced.activity.is.observed.only.at.distances.below.10.nm,.
it. is. hypothesized. that. photonic. energy. is. also. being. absorbed. by. the. quantum. dot. and.
transferred.not.through.luorescent.emission,.but.through.radiationless.FRET—not.unlike.
that.seen.in.complex.antenna.protein.arrays.
Currently,.efforts.are.being.made.to.combine.this.quantum.dot.enhancement.with.the.
electrolyteless. gold. substrate. presented. in. Section. 22.4. to. create. the. next. generation. of.
quantum-enhanced.electrolyteless.BSSC.devices..Moreover,.the.nonradiative.FRET.trans-
fer. mechanisms. revealed. may. be. one. step. toward. reproducing. the. complex. mechanism.
found.in.natural.photoactive.proteins.
22.7 Conclusions
During.a.long.process.of.evolution,.naturally.occurring.photosynthetic.machineries.like.
antenna.proteins,.photosystems.I.and.II,.bacteriorhidopsin,.and.biochromophores.acquired.
special.structural.features.that.allow.them.to.effectively.capture.the.available.solar.energy.
and. utilize. it. with. an. incredibly. high. light-to-electron. conversion. eficiency.. Moreover,.
they. are. able. to. sustain. their. functionality. for. long. periods. of. time.. Biosensitized. solar.
cell.technology. integrates.these.naturally.eficient.biochemical/mechanical. systems.into.
a. man-made. device. with. the. intention. of. generating. energy. at. a. low. cost. with. minimal.
environmental.impact.
Nevertheless,.these.biomolecules'.extraordinary.performance.often.suffers.when.the.
structures. are. extracted. from. their. natural. environment. and. immobilized. on. an. elec-
trode..This.decline.in.performance.is.proposed.to.occur.due.to.the.undesirable.structural.
and. conformational. changes. impairing. electron. injection. onto. the. electron. acceptor..
These.antagonistic.alterations.during.the.extraction.process.are.more.severe.with.more.
complicated.systems,.like.photosystems.I.and.II..Their.highly.diverse.structures.make.
them. sensitive. to. chemical. and. conformational. changes.. This. requires. a. new. ield. of.
nanoscale.engineering.to.successfully.meld.the.artiicial.and.natural.in.a.way.that.would.
prevent. these. changes.. This. is. a. several-fold. challenge. requiring. an. acute. knowledge.
of. the. intricate. protein. structures,. precise. manipulation. of. nanoscale. substrates,. and.
