Jove
Visualize
Contact Us

Related Concept Videos

Determining the pH of Salt Solutions04:08

Determining the pH of Salt Solutions

46.5K
The pH of a salt solution is determined by its component anions and cations. Salts that contain pH-neutral anions and the hydronium ion-producing cations form a solution with a pH less than 7. For example, in ammonium nitrate (NH4NO3) solution, NO3− ions do not react with water whereas NH4+ ions produce the hydronium ions resulting in the acidic solution.  In contrast, salts that contain pH-neutral cations and the hydroxide ion-producing anions form a solution with a pH greater than 7. For...
46.5K
pH Scale02:41

pH Scale

78.4K
Hydronium and hydroxide ions are present both in pure water and in all aqueous solutions, and their concentrations are inversely proportional as determined by the ion product of water (Kw). The concentrations of these ions in a solution are often critical determinants of the solution’s properties and the chemical behaviors of its other solutes. Two different solutions can differ in their hydronium or hydroxide ion concentrations by a million, billion, or even trillion times. A common means of...
78.4K
pH01:24

pH

142.0K
The potential of hydrogen (pH) is a measure of the acidity or basicity of a water-based solution determined by the concentration of hydronium ions (H3O+). In one liter of pure water at neutral pH, there are 1×10−7 moles of hydronium ions. However, the extensive range of hydronium ion concentrations present in water-based solutions makes measuring pH in moles cumbersome. Therefore, a pH scale was developed to convert moles of hydronium ions into the negative logarithm of the hydronium...
142.0K
Acid–Base Equilibria: Activity-Based Definition of pH01:10

Acid–Base Equilibria: Activity-Based Definition of pH

1.2K
For an ideal solution, the pH is defined as the negative logarithm of the hydrogen ion concentration. For a non-ideal solution, an accurate measurement of the pH must consider the negative logarithm of the hydrogen ion activity rather than concentration. In such a solution, the pH can be more accurately defined as the negative logarithm of a product of the hydrogen ion concentration and its activity coefficient.
In solutions of very low ionic strength—for example, pure water—the...
1.2K
Calculating pH Changes in a Buffer Solution02:45

Calculating pH Changes in a Buffer Solution

57.4K
A buffer can prevent a sudden drop or increase in the pH of a solution after the addition of a strong acid or base up to its buffering capacity; however, such addition of a strong acid or base does result in the slight pH change of the solution. The small pH change can be calculated by determining the resulting change in the concentration of buffer components, i.e., a weak acid and its conjugate base or vice versa. The concentrations obtained using these stoichiometric calculations can be used...
57.4K
Indicators02:39

Indicators

57.5K
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...
57.5K
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies
  1. Home
  3. An Autonomous Ph Sensor For Real-time High-frequency Monitoring Of Ocean Acidification In Estuarine And Coastal Areas.
  1. Home
  3. An Autonomous Ph Sensor For Real-time High-frequency Monitoring Of Ocean Acidification In Estuarine And Coastal Areas.

Related Experiment Video

Extracellular Multi-Unit Recording from the Olfactory Nerve of Teleosts
07:02

Extracellular Multi-Unit Recording from the Olfactory Nerve of Teleosts

Published on: October 6, 2020

7.2K

An Autonomous pH Sensor for Real-Time High-Frequency Monitoring of Ocean Acidification in Estuarine and Coastal

Shulu Zheng1, Fan Yang1, Shikun Huang1

  • 1State Key Laboratory of Marine Environmental Science, College of the Environment and Ecology, Xiamen University, Xiamen 361102, People's Republic of China.

Analytical Chemistry
|December 3, 2025

View abstract on PubMed

Summary
This summary is machine-generated.

A new underwater pH sensor (uSEA-pH) offers robust, high-resolution monitoring for ocean acidification and marine carbon cycle studies. This ion-sensitive field-effect transistor (ISFET) based device provides reliable, real-time data crucial for environmental analysis.

More Related Videos

Manufacturing of a Nafion-coated, Reduced Graphene Oxide/Polyaniline Chemiresistive Sensor to Monitor pH in Real-time During Microbial Fermentation
11:18

Manufacturing of a Nafion-coated, Reduced Graphene Oxide/Polyaniline Chemiresistive Sensor to Monitor pH in Real-time During Microbial Fermentation

Published on: January 7, 2019

8.9K
Multi-analyte Biochip MAB Based on All-solid-state Ion-selective Electrodes ASSISE for Physiological Research
08:03

Multi-analyte Biochip MAB Based on All-solid-state Ion-selective Electrodes ASSISE for Physiological Research

Published on: April 18, 2013

17.8K

Related Experiment Videos

Extracellular Multi-Unit Recording from the Olfactory Nerve of Teleosts
07:02

Extracellular Multi-Unit Recording from the Olfactory Nerve of Teleosts

Published on: October 6, 2020

7.2K
Manufacturing of a Nafion-coated, Reduced Graphene Oxide/Polyaniline Chemiresistive Sensor to Monitor pH in Real-time During Microbial Fermentation
11:18

Manufacturing of a Nafion-coated, Reduced Graphene Oxide/Polyaniline Chemiresistive Sensor to Monitor pH in Real-time During Microbial Fermentation

Published on: January 7, 2019

8.9K
Multi-analyte Biochip MAB Based on All-solid-state Ion-selective Electrodes ASSISE for Physiological Research
08:03

Multi-analyte Biochip MAB Based on All-solid-state Ion-selective Electrodes ASSISE for Physiological Research

Published on: April 18, 2013

17.8K

Area of Science:

  • Environmental Science
  • Oceanography
  • Sensor Technology

Background:

  • Real-time ocean pH monitoring is vital for understanding ocean acidification and the marine carbon cycle.
  • Existing ion-sensitive field-effect transistor (ISFET) technologies face challenges in practical marine deployment.
  • There is a need for robust, high-resolution pH sensors for estuarine and coastal environments.

Purpose of the Study:

  • To develop and characterize a novel underwater pH sensor (uSEA-pH) based on ISFET technology.
  • To assess the sensor's performance for high-frequency and long-term in situ environmental monitoring.
  • To provide a viable solution for continuous pH measurements in challenging marine settings.

Main Methods:

  • Modification of a commercial laboratory pH probe using engineering design to create the uSEA-pH.
  • Laboratory characterization of the sensor's response, accuracy, and power consumption.
  • In situ deployment for underway and long-term monitoring in estuarine and bay environments.

    • Main Results:

    • The uSEA-pH demonstrated a Nernstian response (slope -57.60 ± 1.05 mV/pH, R² > 0.999) and rapid response time (~7 s).
    • The sensor achieved low measurement uncertainty (<0.01 pH) with low power consumption (0.72 W) and high sampling frequency (1 Hz).
    • Successful detection of subtle pH variations (<0.05 pH) and reliable recording of tidal-driven fluctuations over extended deployments (up to 27 days).

    Conclusions:

    • The developed uSEA-pH is a viable, robust, and high-resolution sensor for continuous pH monitoring.
    • Its compact design and low power consumption facilitate deployment on various observational platforms.
    • The sensor provides critical data for estuarine and coastal environmental analysis, supporting research on ocean acidification and carbon cycling.