Sniffing Bacteria with a Carbon-Dot Artificial Nose

• 作者: Nitzan Shauloff Ahiud Morag Karin Yaniv Seema Singh Ravit Malishev Ofra Paz-Tal Lior Rokach Raz Jelinek
• 来源期刊: 纳微快报（英文版）
• 年，卷（期）: 2021,（7）
• 页码范围: 138-152
• 页数: 15页
• 语种: 英文

摘要

Continuous,real-time monitoring and identifica-tion of bacteria through detection of microbially emitted volatile molecules are highly sought albeit elusive goals.We introduce an artificial nose for sensing and distinguishing vapor molecules,based upon recording the capacitance of interdigitated elec-trodes(IDEs)coated with carbon dots(C-dots)exhibiting differ-ent polarities.Exposure of the C-dot-IDEs to volatile molecules induced rapid capacitance changes that were intimately depend-ent upon the polarities of both gas molecules and the electrode-deposited C-dots.We deciphered the mechanism of capacitance transformations,specifically substitution of electrode-adsorbed water by gas molecules,with concomitant changes in capaci-tance related to both the polarity and dielectric constants of the vapor molecules tested.The C-dot-IDE gas sensor exhibited excellent selectivity,aided by application of machine learning algorithms.The capacitive C-dot-IDE sensor was employed to continuously monitor microbial proliferation,discriminating among bacteria through detection of distinctive"volatile compound fingerprint"for each bacterial species.The C-dot-IDE platform is robust,reusable,readily assembled from inexpensive building blocks and constitutes a versatile and powerful vehicle for gas sensing in general,bacterial monitoring in particular.