| Products/Services Used | Details | Operation |
|---|---|---|
| Custom DNA/RNA Oligos | Sulfosuccinimidyl-4-(N-maleimidomethyl)-cyclohexane-1-carboxylate (Sulfo-SMCC) and tris (2-carboxyethyl) phosphine (TCEP) were purchased from Sigma (USA). Sodium chloride (NaCl), sodium phosphate (Na3PO4), sodium dihydrogenphosphate (NaH2PO4), disodium hydrogen phosphate (Na2HPO4), tris (hydroxymethyl) aminomethane (Tris-HCl), ethylenediaminetetraacetic acid (EDTA) and Tween-20 were purchased from Sinophorm Chemical Reagent Co., Ltd (China). All chemicals were of analytical grade and used without further purification. Buffer I containing 0.2 M NaCl and 0.1 M Na3PO4 (pH = 7.3), Buffer II containing 10 mM Tris-HCl (pH = 7.5), 1 mM EDTA, 1 M NaCl, 0.1% Tween-20 and 0.2 M sodium phosphate buffer (pH = 5.5) of 0.2 M NaH2PO4 and 0.2 M Na2HPO4 were prepared. Grade VII invertase from baker's yeast (S. cerevisiae) was purchased from Sigma (USA). The fetal bovine serum (FBS) was purchased from Gibco (USA). The DNA oligonucleotides used were purchased from Genscript (China). Amicon 3 KDa and 100 KDa centrifugal filters were purchased from Millipore (Germany). Streptavidin-coated MBs (2 μm in diameter) were purchased from Beaver (China). Ultrapure water in the experiment was provided by the Milli-Q Academic system (USA). The PGM was from Roche in the model of ACCU-CHEK Active [43]. | Get A Quote |
A portable, quantitative and selective DNA detection biosensor requiring only one step for target recognition and signal reporter generation using a loop-based DNA competitive hybridization assay and personal glucose meter (PGM) was developed. In the presence of target DNA, due to its competitive binding, the invertase-DNA conjugate was released which could be collected with the help of a magnet subsequently. The released invertase-DNA was used to catalyze the hydrolysis of sucrose into glucose with millions of turnovers which was target concentration dependent. We found that there was a linear relationship between the PGM signals and the target DNA concentration in the range of 100 pM to 100 nM with a dete... More
