Abstract:
This dissertation aimed to develop a novel biosensor using pyrrolidinyl peptide nucleic acid (acpcPNA) as a bioreceptor for the determination of DNA, which indicate the different types of disease. The topic in this research can be divided into 2 parts. The first part is the development of DNA sensors using paper-based analytical device coupled with electrochemical detection. Square-wave voltammetry (SWV) and electrochemical impedance spectroscopy (EIS) were used for the quantification of human papillomavirus (HPV) and Mycobacterium tuberculosis (MTB), repectively. These systems offer sensitive determination with a low detection limit of 2.3 nM (HPV) and 1.24 (MTB). The second part is the development of DNA sensors using paper-based analytical device coupled with colorimetric detection. The proposed biosensor was designed for the simultaneous determination of Middle East Respiratory Syndrome coronavirus (MERS-CoV), MTB and HPV. Silver nanoparticles (AgNPs) was used as a colorimetric reagent to obtain the color change, which is dependent on the DNA concentration. The limit of detection was found to be 1.53, 1.27 and 1.03 nM for MERS-CoV, MTB and HPV, respectively. The selectivity for three developed biosensor was demonstrated by the outstanding properties of acpcPNA. Moreover, the developed biosensors were successfully applied to detect DNA target in biological sample. These results indicate that the proposed paper-based DNA sensors have potential to be an alternative device for low-cost, simple, sensitive and selective for DNA detection relative to traditional methods.
