Antibody-engineered red blood cell interface for high-performance capture and release of circulating tumor cells

Circulating tumor cells(CTCs),as important liquid biopsy target,can provide valuable information for cancer progress monitoring and individualized treatment.However,current isolation platforms incapable of balancing capture efficiency,specificity,cell viability,and gentle release have restricted the clinical applications of CTCs.Herein,inspired by the structure and functional merits of natural membrane interfaces,we established an antibody-engineered red blood cell(RBC-Ab)affinity interface on microfluidic chip for high-performance isolation and release of CTCs.The lateral fluidity,pliability,and anti-adhesion property of the RBC microfluidic interface enabled efficient CTCs capture(96.5%),high CTCs viability(96.1%),and high CTCs purity(average 4.2-log depletion of leukocytes).More importantly,selective lysis of RBCs by simply changing the salt concentration was utilized to destroy the affinity interface for efficient and gentle release of CTCs without nucleic acid contamination.Using this chip,CTCs were successfully detected in colon cancer samples with 90%sensitivity and 100%specificity(20 patients and 10 healthy individuals).After the release process,KRAS gene mutations of CTCs were identified from all the 5 cancer samples,which was consistent with the results of tissue biopsy.We expect this RBC interface strategy will inspire further biomimetic interface construction for rare cell analysis.

Synergistic enhancement effect of polydopamine-polyethyleneimine hybrid films for a visible-light photoelectrochemical biosensing interface

Photoelectrochemical(PEC)active interfaces exhibiting visible-light responses and good electron-transfer ca-pabilities are key to the development of PEC biosensors.In this study,bioinspired polydopamine(PDA)-polyethyleneimine(PEI)hybrid films were designed to engineer inorganic semiconductors and construct PEC biosensing interfaces.The charge-transfer capability and visible-light-response property of PDA were combined with the electron-attracting ability of PEI to produce a synergistic PEC-enhancement effect.The achieved PEC-enhancement effect was versatile for photoanode and photocathode semiconductors.Further,the role of PEI doping was revealed via electrochemical investigations.Compared with the PDA sensing platform,the hybrid sensing interface offered by the PDA-PEI film exhibited enhanced analytical performances toward ascorbic acid(AA),achieving a larger detection range and a lower limit of detection.