Related Experiment Video
Updated: Jan 27, 2026

Synthesis and Functionalization of Nitrogen-doped Carbon Nanotube Cups with Gold Nanoparticles as Cork Stoppers
Published on: May 13, 2013
Determination of cholic acid in body fluids by β‑cyclodextrin-modified N-doped carbon dot fluorescent probes
1Department of Chemistry, Shanxi Normal University, Linfen 041004, PR China.
Abstract:
An easy, dependable, and sensitive cholic acid activity experiment was designed based on β‑cyclodextrin-modified carbon dot (β‑CD-CD) nanoprobes with specific host-guest recognizing ability and photoelectron transfer capability. The β‑CD-CD nanoprobes were characterized by infrared, ultraviolet-visible, and fluorescence spectroscopy and transmission electron microscopy. The fluorescence of the probes under optimized conditions linearly responded to cholic acid concentration from 0 to 650 μmol·L-1 with a detection limit of 25 nmol·L-1. The probes also performed well in detecting cholic acid in serum and urine samples with an average recovery rate of 97.1%-103.4%. Thus, this study provides a reliable, rapid, and easy method of cholic acid detection in body fluids that can be potentially applied in medical studies.
Related Concept Videos
Composition of Body Fluids
Bicarbonate-Carbonic Acid Buffer
Body Water Content and Fluid Compartments
The Carbon Cycle
Carbon Skeletons
Dot Product
In engineering, the dot product of any two vectors is the product of the magnitudes of the vectors and the cosine of the angle between them. It is denoted by a dot symbol between the two vectors.
Consider a vehicle pulling an object along the ground using a rope. If the rope makes an angle with the horizontal axis, the work done can be calculated using the dot product of the force applied and the object's displacement.
The dot...

