John, SVRotherham, LSKhati, MMamba, BBArotiba, OA2014-08-272014-08-272014-07John, S.V, Rotherham, L.S, Khati, M, Mamba, B.B and Arotiba, O.A. 2014. Towards HIV detection: Novel Poly(propylene imine) Dendrimer-Streptavidin platform for electrochemical DNA and gp120 aptamer biosensors. International Journal of Electrochemical Science, vol. 9, pp 5425-54371452-3981http://www.electrochemsci.org/papers/vol9/91005425.pdfhttp://hdl.handle.net/10204/7644Copyright: 2014 Electrochemical Science Group. This is an Open Access journal. The journal authorizes the publication of the information herewith contained. Published in International Journal of Electrochemical Science, vol. 9, pp 5425-5437The detection of sequence – specific DNA and HIV glycoprotein 120 (gp120) based on novel generation 4 poly(propylene imine) dendrimer/streptavidin platform is reported. The platform was prepared by the electrodeposition of the dendrimer on a carbon electrode followed by drop coating with streptavidin. The generation 4 poly(propylene imine) dendrimer/streptavidin platform was characterised using scanning electron microscopy, voltammetry and electrochemical impedance spectroscopy (EIS). Electrochemical measurements indicated that the platform was stable, conducting and exhibited reversible electrochemistry at a former potential of 140 mV in pH 7.5 phosphate buffer saline solution (PBS), while EIS interrogation using [Fe(CN)(sub6)(sup3-/4-)] redox probe showed a marked reduction in charge transfer resistance (Rct) after modification. The biosensor was prepared by the immobilisation of single stranded 5'- biotynilated probe DNA and B40 aptamer on the modified electrode and then used to detect complementary DNA and gp120 respectively. The biosensor responses were evaluated with square wave voltammetry (SWV) and EIS in the presence of PBS and Fe(CN)(sub6)(sup3-/4-)redox probe. A detection limit of 3.44 x 10(sup-12) M (S/N = 3) and linearity r(sup2)= 0.9985 were obtained for the DNA biosensor while the aptamer biosensor detected gp120 in the nanomolar concentration range. The DNA biosensor also showed excellent selectivity in the presence of non complementary and mismatch DNA strands.enBiosensorsAptamersHIVgp120Poly (propylene imine) dendrimerStreptavidinArticleJohn, S., Rotherham, L., Khati, M., Mamba, B., & Arotiba, O. (2014). Towards HIV detection: Novel Poly(propylene imine) Dendrimer-Streptavidin platform for electrochemical DNA and gp120 aptamer biosensors. http://hdl.handle.net/10204/7644John, SV, LS Rotherham, M Khati, BB Mamba, and OA Arotiba "Towards HIV detection: Novel Poly(propylene imine) Dendrimer-Streptavidin platform for electrochemical DNA and gp120 aptamer biosensors." (2014) http://hdl.handle.net/10204/7644John S, Rotherham L, Khati M, Mamba B, Arotiba O. Towards HIV detection: Novel Poly(propylene imine) Dendrimer-Streptavidin platform for electrochemical DNA and gp120 aptamer biosensors. 2014; http://hdl.handle.net/10204/7644.TY - Article AU - John, SV AU - Rotherham, LS AU - Khati, M AU - Mamba, BB AU - Arotiba, OA AB - The detection of sequence – specific DNA and HIV glycoprotein 120 (gp120) based on novel generation 4 poly(propylene imine) dendrimer/streptavidin platform is reported. The platform was prepared by the electrodeposition of the dendrimer on a carbon electrode followed by drop coating with streptavidin. The generation 4 poly(propylene imine) dendrimer/streptavidin platform was characterised using scanning electron microscopy, voltammetry and electrochemical impedance spectroscopy (EIS). Electrochemical measurements indicated that the platform was stable, conducting and exhibited reversible electrochemistry at a former potential of 140 mV in pH 7.5 phosphate buffer saline solution (PBS), while EIS interrogation using [Fe(CN)(sub6)(sup3-/4-)] redox probe showed a marked reduction in charge transfer resistance (Rct) after modification. The biosensor was prepared by the immobilisation of single stranded 5'- biotynilated probe DNA and B40 aptamer on the modified electrode and then used to detect complementary DNA and gp120 respectively. The biosensor responses were evaluated with square wave voltammetry (SWV) and EIS in the presence of PBS and Fe(CN)(sub6)(sup3-/4-)redox probe. A detection limit of 3.44 x 10(sup-12) M (S/N = 3) and linearity r(sup2)= 0.9985 were obtained for the DNA biosensor while the aptamer biosensor detected gp120 in the nanomolar concentration range. The DNA biosensor also showed excellent selectivity in the presence of non complementary and mismatch DNA strands. DA - 2014-07 DB - ResearchSpace DP - CSIR KW - Biosensors KW - Aptamers KW - HIV KW - gp120 KW - Poly (propylene imine) dendrimer KW - Streptavidin LK - https://researchspace.csir.co.za PY - 2014 SM - 1452-3981 T1 - Towards HIV detection: Novel Poly(propylene imine) Dendrimer-Streptavidin platform for electrochemical DNA and gp120 aptamer biosensors TI - Towards HIV detection: Novel Poly(propylene imine) Dendrimer-Streptavidin platform for electrochemical DNA and gp120 aptamer biosensors UR - http://hdl.handle.net/10204/7644 ER -