Jove
Visualize
联系我们
JoVE
x logofacebook logolinkedin logoyoutube logo
关于 JoVE
概览领导团队博客JoVE 帮助中心
作者
出版流程编辑委员会范围与政策同行评审常见问题投稿
图书馆员
用户评价订阅访问资源图书馆顾问委员会常见问题
研究
JoVE JournalMethods CollectionsJoVE Encyclopedia of Experiments存档
教育
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab Manual教师资源中心教师网站
使用条款与条件
隐私政策
政策

相关概念视频

pH01:24

pH

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 ion...
Mixtures of Acids03:27

Mixtures of Acids

The pH of a solution containing an acid can be determined using its acid dissociation constant and its initial concentration. If a solution contains two different acids, then its pH can be determined using one of several methods depending upon the relative strength of the acids and their dissociation constants.
A Mixture of a Strong Acid and a Weak Acid
In a mixture of a strong acid and a weak acid, the strong acid dissociates completely and becomes a source of almost all the hydronium ions...
Calculating pH Changes in a Buffer Solution02:45

Calculating pH Changes in a Buffer Solution

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...
pH01:24

pH

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 ion...
Composition of Polyprotic Acid Solutions as a Function of pH01:19

Composition of Polyprotic Acid Solutions as a Function of pH

Polyprotic acids of the type H2M constitute two ionizable protons. As a result, on titration with a base, they exhibit two equivalence points in the titration curve. During titration, the species H2M, HM−, and M2− will be present in the solution at different points. The fractions of H2M, HM−, and M2− present at the various instances of the titration are denoted by α0, α1, and α2, respectively.
A graph with the alpha values is plotted against the volume of base added during titration. Here, a...
Extraction: Effects of pH00:53

Extraction: Effects of pH

Consider a neutral form of an amine, B, with a partition coefficient, K, in a liquid mixture containing organic and aqueous phases. The pH of the aqueous phase affects the charge on acidic and basic solutes, and the charged form is usually more soluble in the aqueous phase. Suppose the conjugate acid form of the amine is soluble only in the aqueous phase while the base form is soluble in both phases. Then the distribution coefficient, D, can be given as the ratio of amine concentration in the...

您也可能阅读

相关文章

通过共同作者、期刊和引用图与本文相关的文章。

排序
Same author

Idiopathic Gangrene of the Four Extremities, Resembling Gangrenous Ergotism.

Medical examiner (Philadelphia, Pa.)·2023
Same author

Glycogenia: The Secretion of Sugar in the Human Economy.

Medical examiner (Philadelphia, Pa.)·2023
Same author

On the Secretion of Sugar in the Animal Economy.

Iowa medical journal·2023
Same author

Glycogenia-The Secretion of Sugar in the Human Economy.

Atlanta medical and surgical journal·2022
Same author

Probing the gel to liquid-crystalline phase transition and relevant conformation changes in liposomes by (13)C magic-angle spinning NMR spectroscopy.

Biochimica et biophysica acta·2015
Same author

Probing structural and motional features of organic and inorganic solids through extended family of cross-polarization experiments.

Solid state nuclear magnetic resonance·2015

相关实验视频

Updated: Jul 9, 2026

Simultaneous pH Measurement in Endocytic and Cytosolic Compartments in Living Cells using Confocal Microscopy
09:46

Simultaneous pH Measurement in Endocytic and Cytosolic Compartments in Living Cells using Confocal Microscopy

Published on: April 28, 2014

通过高分辨率固态13C NMR测定pH和pK值:溶解液化L-histidine的酸和分体平衡.

Bernard Henry1, Piotr Tekely, Jean-Jacques Delpuech

  • 1Laboratoire de Chimie Physique Organique et Colloïdale, Unité Mixte de Recherche CNRS-UHP (UMR 7565), Université Henri Poincaré-Nancy I, B.P. 239, 54506 Nancy-Vandoeuvre Cedex, France.

Journal of the American Chemical Society
|February 28, 2002
PubMed
概括

固态NMR现在可以测量冷粉末的pK值,准确地预测它们在再水后的in situ pH. 这种方法提供了一个非侵入性的方法来确定酸度,当传统方法失败时.

更多相关视频

Functional Characterization of Na+/H+ Exchangers of Intracellular Compartments Using Proton-killing Selection to Express Them at the Plasma Membrane
07:38

Functional Characterization of Na+/H+ Exchangers of Intracellular Compartments Using Proton-killing Selection to Express Them at the Plasma Membrane

Published on: March 30, 2015

Highly Sensitive and Quantitative Detection of Proteins and Their Isoforms by Capillary Isoelectric Focusing Method
07:58

Highly Sensitive and Quantitative Detection of Proteins and Their Isoforms by Capillary Isoelectric Focusing Method

Published on: September 19, 2018

相关实验视频

Last Updated: Jul 9, 2026

Simultaneous pH Measurement in Endocytic and Cytosolic Compartments in Living Cells using Confocal Microscopy
09:46

Simultaneous pH Measurement in Endocytic and Cytosolic Compartments in Living Cells using Confocal Microscopy

Published on: April 28, 2014

Functional Characterization of Na+/H+ Exchangers of Intracellular Compartments Using Proton-killing Selection to Express Them at the Plasma Membrane
07:38

Functional Characterization of Na+/H+ Exchangers of Intracellular Compartments Using Proton-killing Selection to Express Them at the Plasma Membrane

Published on: March 30, 2015

Highly Sensitive and Quantitative Detection of Proteins and Their Isoforms by Capillary Isoelectric Focusing Method
07:58

Highly Sensitive and Quantitative Detection of Proteins and Their Isoforms by Capillary Isoelectric Focusing Method

Published on: September 19, 2018

科学领域:

  • 固态NMR光谱学 固态NMR光谱学
  • 物理化学 物理化学
  • 生物化学 生物化学

背景情况:

  • L-histidine的酸特性对其生物功能至关重要.
  • 研究冷解粉末需要非侵入性表征方法.
  • 对于某些样本类型,传统的pK确定方法可能具有挑战性.

研究的目的:

  • 系统地研究冷化L-histidine粉末的酸性质.
  • 建立固态NMR作为pK确定可靠的方法.
  • 为了实现粉末酸度的非侵入性表征,并预测in situ pH.

主要方法:

  • 高分辨率固态13CNMR和1HCRAMPSNMR光谱学. 这是一种高分辨率的固态13CNMR和1HCRAMPSNMR光谱.
  • 在pH范围 (1.8-10) 中使用母溶液进行固态定位.
  • 从固态酸比率 (r) 计算pK值.

主要成果:

  • 固态13C核磁共振成功地解决了L-histidine的所有三种酸对.
  • 1H CRAMPS NMR证实中性/阴性物种中没有N3-H(pi) 互相体.
  • 固态确定的pK值与基于溶液的测量结果相匹配,验证了该方法.

结论:

  • 固态NMR为冷解粉末提供了准确的pK测量,与溶液方法相似.
  • 这种技术允许对粉末酸度进行非侵入性表征,并预测in situ pH.
  • 该方法将pK的确定范围扩展到具有挑战性的系统,如非水性溶剂和传统方法不适合的化物.