関連する実験動画

Updated: Aug 3, 2026

Hydrophobic Salt-modified Nafion for Enzyme Immobilization and Stabilization
11:16

Hydrophobic Salt-modified Nafion for Enzyme Immobilization and Stabilization

Published on: July 11, 2012

サイクルポリエーテル・プロトン化有機アミン結合:酵素およびイオン輸送プロセスにおける重要性

R M Izatt, N E Izatt, B E Rossiter

    Science (New York, N.Y.)
    |March 3, 1978
    PubMed
    まとめ

    周期性ポリエーテル18-クラウン-6は,陽子化されたアミンと複合体を形成する. 複合体の安定性は,アミンプロトネーションの増加とともに低下し,エンタピーの変化によって引き起こされる膜の透過性と相関する.

    さらに関連する動画

    Facile Protocol for the Synthesis of Self-assembling Polyamine-based Peptide Amphiphiles (PPAs) and Related Biomaterials08:55

    Facile Protocol for the Synthesis of Self-assembling Polyamine-based Peptide Amphiphiles (PPAs) and Related Biomaterials

    Published on: June 25, 2018

    Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides11:04

    Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides

    Published on: September 7, 2019

    関連する概念動画

    ATP Driven Pumps I: An Overview01:27

    ATP Driven Pumps I: An Overview

    ATP-driven pumps, also known as transport ATPases, are integral membrane proteins. They have binding sites for ATP located on the membrane's cytosolic side and the ion-conducting domain in the transmembrane region. These pumps use the free energy released from ATP hydrolysis to move the solutes across cell membranes against an electrochemical gradient.
    There are four main types of ATP-driven pumps - P-type, V-type, F-type, and ABC transporter. All these pumps are of varying complexities and are...
    Basicity of Aliphatic Amines01:21

    Basicity of Aliphatic Amines

    Amines can behave as Brønsted–Lowry bases by accepting a proton from the acid to form corresponding conjugate acids. Due to a lone pair of nonbonding electrons, aliphatic amines can also act as Lewis bases by forming a covalent bond with an electrophile.
    To measure the basicity of amines, two conventions are generally used. The first defines Kb as the basicity constant for the deprotonation reaction of water by the amine, as presented in Figure 1. Conventionally, lower Kb indicates higher...
    Basicity of Heterocyclic Aromatic Amines01:25

    Basicity of Heterocyclic Aromatic Amines

    Heterocyclic amines, where the N atom is a part of an alicyclic system, are similar in basicity to alkylamines. Interestingly, the heterocyclic amine having a nitrogen atom as part of an aromatic ring has much less basicity than its corresponding alicyclic counterpart. For this reason, as presented in Figure 1, piperidine (pKb = 2.8) is significantly more basic than pyridine (pKb = 8.8).
    Amines to Amides: Acylation of Amines01:19

    Amines to Amides: Acylation of Amines

    Various carboxylic acid derivatives (such as acid chlorides, esters, and anhydrides) can be used for the acylation of amines to yield amides. The reaction requires two equivalents of amines. The first amine molecule functions as a nucleophile and attacks the carbonyl carbon to produce a tetrahedral intermediate. This is followed by the loss of the leaving group and restoration of the C=O bond.
    Next, the second equivalent of amine serves as a Brønsted base and deprotonates the quaternary amide...
    EDTA: Chemistry and Properties01:22

    EDTA: Chemistry and Properties

    Polydentate ligands are most widely used in complexometric titrations because they form more stable complexes with the metal ions than mono- or bidentate ligands due to the chelate effect. Examples of polydentate ligands are ethylenediaminetetraacetic acid (EDTA), crown ethers, and cryptands. The most important feature of optimal polydentate ligands is the ability to form 1:1 complexes in a single-step process. Amino carboxylic acid derivatives are frequently used as complexing agents. EDTA is...
    Pore Transport and Ion-Pair Transport01:17

    Pore Transport and Ion-Pair Transport

    Pore transport and ion-pair formation are critical mechanisms for the absorption and distribution of drugs in the body.
    Pore transport, also known as convective transport, is a process where small molecules like urea, water, and sugars rapidly cross cell membranes as though there were channels or pores in the membrane. Although direct microscopic evidence is limited  but the concept of pores or channels is widely accepted based on physiological evidence. Despite the lack of direct microscopic...