Design of a Mycobacterial Porin Based Dye Sensitized Solar Cell

Objective : Background

Pre-program Medication Errors (Jan-Sep 2006; n=191)

MspA is Highly Versatile! Cytotoxic

Drug Delivery System for Cancer Treatment

Stable Supramolecular Building Unit

Improved Cure for Tuberculosis

Nano reactor for Synthesis of Gold-Nanoparticles, Nano-dots and Nano-antennae

Defined Protein-Matrix for Vectorial Electron-Transport in Solar Cells

DNA Sequencing Using Channel Activity

Quenching Heavy Metals from Biological Systems

MspA is a trans-membrane channel-forming protein from Mycobacterium smegmatis

It mediates transport of ions across the cell membrane

Octamer, 160 kDa

Extremely stable: 100oC in SDS & pH 2-10

Contains 96 free –COOH & 8 -NH2’s

MspA mutant A96C contains cysteine at terminal of docking zone

MspA liquid extracts & crystals can be obtained in high yield

It can be characterized by methods such as gel electrophoresis & HPLC

Electron Excitation

N

N

H2N

N N

NH2

Ru2+

N+

N+N

O

O

NH

ON

N

Ru based dye

Maleimide linker

MspA

Experimental Methods

To produce a ‘green’ dye sensitized solar cell with a protein electrolytic matrix

Ayomi S. Perera*, Mausam Kalita*, Navaneetha K. Subbaiyan†, Francis D’Souza† and Stefan H. Bossmann*Kansas State University*, Wichita State University†

MspA liquid extract

MspA crystal

Gel electrophoresis

HPLC

MspA

N N

NH2

N+

N+

NO O

OH

O

N+

N+

NO O

NH

O

NN

1)

0.82 mmol0.15 g, 1 eq.

0.385 mmol0.07 g, 1.2 eq

EDC 1.23 mmol, 1.5 eqHOBT 0.82 mmol, 1 eq

2) RuCl3.3H2O + DMSO0.38 mmol 4 ml0.1 g

Reflux 30 min Ru(DMSO)4Cl2

(pale yellow)

1.Cool to r.t.2.Add 25 ml H2O

3.Heat 100 oC, 2h

[Ru(DMSO)4-n(H2O)n]2+ 1.Cool to 60 oC

2. Add X dropwise over 1h, at 40 oC, in EtOH/H2O

Experimental Methods

(X)

1.Stir intensively at 60 oC 10h2.Add 0.55 mmol (0.100 g) of 1,10-phenanthroline-5-amine, keep at 60 oC, 1h3. Cool to r.t.4. Evaporate excess solvent5. Check TLC : two compounds6. Separate by Al2O3 column7. Characterize by 1HNMR & mass spectra

3)

N

N

H2N

N N

NH2

Ru2+

N+

N+N

O

O

NH

ON

N

N

N

H2N

N N

NH

Ru2+

N+

N+N

O

O

NH

ON

N

O

N+

N+

N

O

O

Results & Conclusion

1% Conversion of sunlight into current

First ever ‘Protein Nano Solar Cell’!

Ru (2) Ru (1)

Ru (1)orRu (2)

+ A96C MspA with terminal cysteine

EDC coupling

N

N

H2N

N N

NH2

Ru2+

N+

N+N

O

O

NH

ON

N

1. Adsorb onto TiO2

2. Expose to sunlight3. Measure voltage & current

Double bond of maleimide reacts with –SH of cysteine

Cysteine

M. smegmatis

http://en.wikipedia.org/wiki/File:Msmegmatiswiki.jpg

Niederweis, M. Molecular microbiology 2003, 49(5), 1167-1177

Faller, M. et al. Science 303, 1189 (2004)

Ru (1)&Ru (2)

TiO2 Nano Particles

Acknowledgement:National Science Foundation under Award No. EPS-0903806 and matching support from the State of Kansas through Kansas Technology Enterprise Corporation