Inkjet printed and "doctor blade" TiO2 photodetectors for DNA biosensors.
A dye sensitized TiO(2) photodetector has been integrated with a DNA detection method based on non-cross-linking hybridization of DNA-functionalized gold nanoparticles, resulting in a disposable colorimetric biosensor. We present a new approach for the fabrication of dye sensitized TiO(2) photodetectors by an inkjet printing technique-a non-contact digital, additive, no mask and no vacuum patterning method, ideal for cost efficient mass production. The developed biosensor was compared against a dye sensitized photodetector fabricated by the traditional "doctor blade" method. Detection of gold nanoparticle aggregation was possible for concentrations as low as 1.0 nM for the "doctor blade" system, and 1.5 nM for the inkjet printed photodetector. The demonstrated sensitivity limits of developed biosensors are comparable to those of spectrophotometric techniques (1.0 nM). Our results show that a difference higher than 17% by traditional photodetector and 6% by inkjet printed in the photoresponses for the complementary and non-complementary gold nanoprobe assays could be attained for a specific DNA sequence from Mycobacterium tuberculosis, the etiologic agent of human tuberculosis. The decrease of costs associated with molecular diagnostic provided by a platform such as the one presented here may prove of paramount importance in developing countries.
CENIMAT/I3N, Departamento de Ciência dos Materiais, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Portugal.
Iwona
I
Bernacka-Wojcik
Rohan
R
Senadeera
Pawel Jerzy
PJ
Wojcik
Leonardo Bione
LB
Silva
Gonçalo
G
Doria
Pedro
P
Baptista
Hugo
H
Aguas
Elvira
E
Fortunato
Rodrigo
R
Martins
D015374:Biosensing Techniques / Q000295:instrumentation*; D016287:Computer Peripherals; D004269:DNA, Bacterial / Q000032:analysis*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D009169:Mycobacterium tuberculosis / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation*; D010783:Photometry / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014025:Titanium / Q000737:chemistry*
D004269:DNA, Bacterial; C009495:titanium dioxide; D014025:Titanium