Electrostatic Cell Trapping for Enhanced Sample Yield in Brush Cytology.

Area of Science:

• Biomedical Engineering
• Materials Science
• Gastroenterology

Background:

• Brush cytology is crucial for detecting gastrointestinal malignancies.
• Low cellular yield in current brushing techniques limits diagnostic sensitivity.
• Electrostatic interactions offer a potential method to improve cell capture.

Purpose of the Study:

• To investigate the use of electrostatic interactions to enhance cancer cell capture during cytological brushing.
• To modify polyamide (PA) bristles with poly(ethylenimine) (PEI) to increase affinity for negatively charged cancer cells.

Main Methods:

• Physical analysis of electrostatic attraction and hydrodynamic drag forces on cancer cells.
• Modification of PA bristles with PEI.
• In vitro experiments using HeLa cells.
• Ex vivo brushing of porcine stomach tissue.

Main Results:

• Electrostatic attraction was found to significantly contribute to cell trapping, balancing hydrodynamic forces.
• In vitro tests showed a 2-fold increase in cancer cell attachment to modified brushes.
• Ex vivo tests demonstrated an approximately 5-fold increase in cellularity in brushed tissue samples.

Conclusions:

• Exploiting electrostatic attraction between cancer cells and modified bristles enhances cell capture efficiency.
• This simple, cost-effective method can improve the sensitivity and specificity of cytological brushing for cancer detection.