概括
这项研究引入了一种新的液晶 (LC) 传感器,用于使用低声画廊模式 (WGM) 分析进行广泛的pH测量. 传感器通过LC微滴的结构变化直接检测pH值变化,提供了灵敏且无标签的检测方法.
科学领域:
- 材料科学 材料科学 材料科学
- 分析化学 分析化学
- 光学是什么?光学是什么?光学是什么?
背景情况:
- 在医疗保健,环境,食品和农业部门,pH检测至关重要.
- 现有的pH传感器通常需要中间体或复杂的设置.
- 液晶具有独特的光电子特性,适用于传感应用.
研究的目的:
- 开发一种广泛的pH传感器,利用液晶对pH变化的直接反应.
- 在不同的pH条件下研究LC微滴的结构和光谱变化.
- 建立一种无标签和直接的pH测量方法.
主要方法:
- 作为球形共振器,使用了4--4'-乙烯 (5CB) 液晶微滴.
- 采用极化光学显微镜 (POM) 进行定性形态分析.
- 应用低语画廊模式 (WGM) 光谱学用于定量光谱测量.
主要成果:
- 在性条件下 (pH 7.613.3) 在5CB微滴中观察到完整的结构转变 (双极到辐射).
- 在性条件下,WGM光谱中的红移达到1.78nm/pH的平均灵敏度.
- 在酸性条件下检测到轻微的结构变化和1.06nm/pH的灵敏度,在WGM光谱中出现蓝移 (pH6.651.5).
- 归因于酸性和性溶液的不同折射率的灵敏度差异.
结论:
- 拟议的基于LC的WGM传感器可以在没有中间体的情况下进行广泛的pH测量.
- 该方法为关于pH-LC相互作用的理论研究提供了有价值的参考.
- 证明了为各种应用开发先进的基于液态碳的pH传感器的潜力.
相关概念视频
02:41pH Scale
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...
02:45Calculating 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...
02:19Buffer Effectiveness
Buffer solutions do not have an unlimited capacity to keep the pH relatively constant . Instead, the ability of a buffer solution to resist changes in pH relies on the presence of appreciable amounts of its conjugate weak acid-base pair. When enough strong acid or base is added to substantially lower the concentration of either member of the buffer pair, the buffering action within the solution is compromised.
The buffer capacity is the amount of acid or base that can be added to a given volume...
The buffer capacity is the amount of acid or base that can be added to a given volume...
01:28pH Regulation in Cells
pH plays a critical role in maintaining normal cellular activities. It helps maintain the structure and function of various proteins, dictates the charge on cellular membranes, and is crucial for metabolic reactions inside the cell. Moreover, cells use the energy from the proton motive force to generate ATP.
Cytosolic pH
Under physiological conditions, the cytosolic pH is slightly more acidic than the extracellular pH. However, cells must prevent further acidification of their cytosol to...
Cytosolic pH
Under physiological conditions, the cytosolic pH is slightly more acidic than the extracellular pH. However, cells must prevent further acidification of their cytosol to...
01:31pH Homeostasis
Acid-base homeostasis is essential for maintaining normal physiological activities in humans. The pH of various body fluids is strictly regulated because it is critical for the optimal activity of enzymes involved in metabolic reactions. Enzymes are basically proteins, so, any significant change in pH can affect their structure and activity. In humans, pH is regulated using three primary mechanisms— chemical buffer systems, respiratory regulation, and renal regulation.
Respiratory Regulation of...
Respiratory Regulation of...
01:15Potentiometry: Membrane Electrodes
Membrane electrodes, also known as p-ion electrodes, use membranes that selectively interact with free analyte ions, generating a potential difference across the membrane. The resulting membrane potential, known as the asymmetry potential, is not zero even when analyte concentrations on both sides of the membrane are equal. The membrane's response is typically not selective to a single analyte but proportional to the concentration of all ions in the sample solution capable of interacting at the...