Manoj K Patel1, Ved V Agrawal2, ZA Ansari3, Bansi D Malhotra3, SG Ansari3
1Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi -110025; Department of Science and Technology Centre on Biomolecular Electronics, Biomedical Instrumentation Section, National Physical Laboratory (CSIR), Dr. K. S. Krishnan Marg, New Delhi -110 012, India.
2Department of Science and Technology Centre on Biomolecular Electronics, Biomedical Instrumentation Section, National Physical Laboratory (CSIR), Dr. K. S. Krishnan Marg, New Delhi -110 012, India.
3Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi -110025, India.
ABSTRACT
Nucleic acid sequences are getting importance in nano-biosensing techniques for the detection of various diseases since the sequence has capacity to represent information which directs the functions of a living thing. Therefore, sequence determination is useful in fundamental research to understand why and how organisms live and function. Therefore, knowledge of a DNA sequence may be useful in biological research. For example, in medicine it can be used to identify, diagnose and potentially develop treatments for genetic diseases. Similarly, research into pathogens may lead to treatments for contagious diseases. DNA in an organism’s genome can also be analyzed to diagnose vulnerabilities to inherited diseases. With these importances, DNA sequences have become indispensable for various applications in biological research, DNA sequencing, diagnostic, biotechnology, forensic biology and biological systematic. DNA sequences are also being studied as PCR primers or Probe for nucleic acid based sensors by immobilizing them on nanomaterial surfaces. It is expected that such sensing studies will help in early detection of pathogen which is a need of present time unlike the usual diagnosis procedure of diseases. Thus, Nucleic acids (DNA/RNA) sequence can play an important role in the diagnosis of infectious diseases due to rapid, specific and high sensitive detection with relatively low cost. In this work, Vibrio cholerae sensing studies using 23 mer probe (ssDNA) sequence are carried out early detection of Cholera. This ssDNA probe sequences is specific for the detection of genomic DNA (dsDNA) of sequence of the virulent strain. These probes were immobilized on nanostructured metal oxide (MgO) synthesized by sol-gel technique. MgO films were deposited on ITO glass. After immobilization of ssDNA, its hybridization with complementary or genomic DNA sequences was detected using electrochemical techniques and used as basic sensing characteristics. The ssDNA/dsDNA and MgO complexes were characterized by atomic force microscopy, scanning electron microscopy, Fourier transforms infrared spectroscopy and electrochemical techniques. DNA sensor based on nucleic acid sequence can detect the diseases with high sensitivity as 8.12 nA/ng/cm 2 with regression coefficient (R) as 0.998 for O1 gene. These sensors were found stable for ~ 3-4 months when stored under refrigerated condition. Read more…
