Circulating tumor cells (CTCs) are shed into the peripheral blood from primary and metastatic tumor mass. Their isolation and subsequent molecular analysis hold promise for the cancer diagnostics, therapeutics, and prognostics. So far, several platforms have been developed for detection and isolation of CTCs. However, none of them have unequivocally shown clinical validity. Recently, high-throughput content screening technology has been used to exam unpurified cell populations. In brief, nucleated cells from peripheral blood are enriched onto substrate surfaces and subjected to examination. This method has great potential towards enabling unbiased analysis of CTCs. In pretreatment, fixed cells can be stained and then attached; in the other scenario, viable cells are attached, fixed and stained. Here, we have compared the two methods on Poly-Llysine and amino silane functionalized surfaces. Our results show that viable cells can achieve approximately 98.7% binding yields on silane-coated surface within 30 min incubation at room temperature. The CTC detection platforms based on high throughput screening would benefit from this conclusion.