Related Experiment Video
Updated: Jan 22, 2026
08:56
Visual Detection of Multiple Nucleic Acids in a Capillary Array
Published on: November 15, 2017
7.7K
A visual sensor array based on an indicator displacement assay for the detection of carboxylic acids
You Wang1, Danqun Huo2, Huixiang Wu1
1Key Laboratory of Biorheological Science and Technology of Ministry of Education, State and Local Joint Engineering Laboratory for Vascular Implants, Bioengineering College of Chongqing University, Chongqing, 400044, People's Republic of China.
Mikrochimica Acta
|July 5, 2019
Summary
A novel visual sensor array using indicator displacement assays (IDAs) effectively distinguishes 15 carboxylic acids (CAs) and quantifies pyruvic acid (PA) with high accuracy.
Area of Science:
- Analytical Chemistry
- Chemical Sensing
- Biomarker Detection
Background:
- Carboxylic acids (CAs) are potential biomarkers for diseases and body odors.
- Developing selective and sensitive detection methods for CAs is crucial.
Purpose of the Study:
- To develop a visual sensor array for discriminating carboxylic acids (CAs).
- To enable the quantification of pyruvic acid (PA) using indicator displacement assays (IDAs).
Main Methods:
- Fabrication of sensor arrays using specific metal complexes (Murexide-Ni(II), murexide-Cu(II), zincon-Zn(II), xylenol orange-Cu(II)).
- Utilizing indicator displacement assays (IDAs) for visual detection.
- Applying pattern recognition algorithms (HCA, PCA, LDA) for data analysis.
Main Results:
- The IDA array achieved >96% classification accuracy for 15 CAs.
- Demonstrated a linear range of 10–1500 μM and a detection limit of 3.5 μM for PA.
- Showcased excellent selectivity, robustness, and batch-to-batch reproducibility.
Conclusions:
- The developed IDA sensor array is a promising tool for carboxylic acid discrimination.
- The visual and quantitative capabilities offer a new avenue for biomarker analysis.
- The method provides a rapid (5 min) and accurate approach for CA detection.
Related Concept Videos
01:21Acidity of Carboxylic Acids
8.6K
Carboxylic acids are the strongest organic acids. However, their acidic strength is much less than mineral acids like HCl. Carboxylic acids ionize in water and readily lose the hydroxyl proton to form a resonance-stabilized carboxylate ion.
8.6K
01:18Carboxylic Acids to Acid Chlorides
8.7K
Carboxylic acids react with SOCl2 or PCl5 to form acid chlorides. Amongst the carboxylic acid derivatives, acid chlorides are the most reactive and synthetically important derivatives. They are useful reagents for Friedel–Crafts acylation of some aromatic compounds.
8.7K
02:39Indicators
59.8K
Certain organic substances change color in dilute solution when the hydronium ion concentration reaches a particular value. For example, phenolphthalein is a colorless substance in any aqueous solution with a hydronium ion concentration greater than 5.0 × 10−9 M (pH < 8.3). In more basic solutions where the hydronium ion concentration is less than 5.0 × 10−9 M (pH > 8.3), it is red or pink. Substances such as phenolphthalein, which can be used to determine the pH of a solution, are...
59.8K
01:25Acidity and Basicity of Carboxylic Acid Derivatives
4.2K
Carboxylic acids are the strongest among organic acids, as they readily lose the hydroxyl proton to form a resonance-stabilized carboxylate ion. In comparison, the acid derivatives lack acidic hydrogens directly attached to a functional group. In these compounds, the acidic nature arises from their ability to lose α hydrogens, making them weakly acidic.
The relative acidic strength of the derivatives can be explained based on the extent of resonance stabilization of the conjugate base. The...
The relative acidic strength of the derivatives can be explained based on the extent of resonance stabilization of the conjugate base. The...
4.2K
01:01Acid Halides to Carboxylic Acids: Hydrolysis
3.5K
Hydrolysis of acid halides is a nucleophilic acyl substitution reaction in which acid halides react with water to give carboxylic acids. The reaction occurs readily and does not require acid or a base catalyst.
As shown below, the mechanism involves a nucleophilic attack by water at the carbonyl carbon to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen π bond along with the departure of a halide ion. A final proton transfer step yields carboxylic...
As shown below, the mechanism involves a nucleophilic attack by water at the carbonyl carbon to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen π bond along with the departure of a halide ion. A final proton transfer step yields carboxylic...
3.5K
01:13Preparation of Carboxylic Acids: Carboxylation of Grignard Reagents
6.0K
Carboxylic acids can be prepared by the carboxylation of Grignard reagents (RMgX). This method is convenient for converting alkyl (primary, secondary or tertiary), vinyl, benzyl, and aryl halides to carboxylic acids with one additional carbon than the starting RMgX.
6.0K