Miniplatforms for Screening Biological Samples for KRAS and Four Mismatch Repair Proteins as New Tools for Fast Screening for Gastric and Colon Cancers

Two miniplatforms based on stochastic microsensors designed using Nitrogen (9.3%) and Boron (2.4%) - dopped graphene (NB-DG) modified with frutafit HD and frutafit TEX were designed and validated for the assay of MLH1, MSH2, MSH6, PMS2, and of KRAS in whole blood, urine, saliva, and tumoral tissues. The sensitivities recorded using the miniplatform based on frutafit TEX were higher (MLH1:1.07 x 10(4), MSH2: 5.31; MSH6: 1.58 x 10(3); KRAS: 1.36 x 10(-2) s(-1) mu g(-1) ml) than those recorded when frutafit HD was used. A lower value of the limit of determination (0.32 fg ml(-1)) was recorded for the frutafit HD based miniplatform when used for the assay of MLH1, while the lowest value of the limit of determination for the assay of KRAS (2.2 fg ml(-1)) was recorded when the frutafit TEX was used in the design of the miniplatform. The % recoveries of MLH1, MSH2, MSH6, PMS2, and of KRAS in whole blood, urine, saliva, and tumoral tissues were higher than 99.00 with RSD (%) values lower than 0.08%.