Jove
Visualize
Contact Us
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

Related Concept Videos

Complexometric Titration: Ligands00:43

Complexometric Titration: Ligands

1.1K
Different monodentate and polydentate ligands are used as complexing agents in complexometric titration reactions. The formation of complexes by mono- and bidentate ligands involves two or more intermediate steps, limiting their use as complexing agents. In comparison, polydentate ligands can form complexes with metal ions in a single-step process, facilitating sharper end points. This means polydentate ligands, such as amino carboxylic acid derivatives, are most commonly employed in...
1.1K
Polymers: Molecular Weight Distribution01:10

Polymers: Molecular Weight Distribution

3.8K
For any given polymer, the weight average molecular weight (Mw) is higher than, if not equal to, the number average molecular weight (Mn). The only situation in which the weight average molecular weight and the number average molecular weight are equal is when a polymer consists only of chains with equal molecular weight. However, this never happens in a synthetic polymer, since it is difficult to control the polymerization process up to a molecular level with accuracy to a hundred percent.
3.8K
Factors Affecting Dissolution: Polymorphism, Amorphism and Pseudopolymorphism01:21

Factors Affecting Dissolution: Polymorphism, Amorphism and Pseudopolymorphism

409
Polymorphism refers to the existence of a drug substance in multiple crystalline forms, known as polymorphs. Recently, this term has been expanded to include solvates (forms containing a solvent), amorphous forms (non-crystalline forms), and desolvated solvates (forms from which the solvent has been removed).
Some polymorphic crystals possess lower aqueous solubility than their amorphous counterparts, leading to incomplete absorption. For instance, the oral suspension of Chloramphenicol, which...
409
Complexation Equilibria: The Chelate Effect01:19

Complexation Equilibria: The Chelate Effect

696
In complexation reactions, metal atoms or cations interact with ligands to form donor-acceptor adducts called metal complexes. Ligands that bind through one donor site are monodentate, ligands with two donor sites are bidentate, and those with more than two donor sites are polydentate ligands. For example, ethylene diamine is a bidentate ligand that binds through two nitrogen donor atoms, forming a five-membered ring. EDTA is a polydentate ligand that binds through four oxygen and two nitrogen...
696
Polymers: Defining Molecular Weight01:01

Polymers: Defining Molecular Weight

3.2K
Unlike small molecules with definite molecular weights, polymers are a mixture of individual polymer chains of varying lengths, each with a unique molecular weight.  So, the molecular weight of a polymer is expressed as an average value based on the average size of the polymer chains. The two most common forms of averages used for polymers are the number average molecular weight and weight average molecular weight.
The number average molecular weight (Mn) is the summation of the number...
3.2K
Formation of Complex Ions03:45

Formation of Complex Ions

24.0K
A type of Lewis acid-base chemistry involves the formation of a complex ion (or a coordination complex) comprising a central atom, typically a transition metal cation, surrounded by ions or molecules called ligands. These ligands can be neutral molecules like H2O or NH3, or ions such as CN− or OH−. Often, the ligands act as Lewis bases, donating a pair of electrons to the central atom. These types of Lewis acid-base reactions are examples of a broad subdiscipline called coordination...
24.0K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Neutral Amphiphiles Boost Transfection Efficiency and Reduce Inflammation in Polymer Micelle-Mediated mRNA Delivery.

Bioconjugate chemistry·2026
Same author

Self-Seeded Nucleation of PET in a Benign Solvent Yields a High Modulus Aerogel With Ultra-Low Thermal Conductivity.

Advanced materials (Deerfield Beach, Fla.)·2026
Same author

Care Patterns, Outcomes, and Costs in Peripheral T-Cell Lymphoma Patients with First-Line Treatment in Routine Clinical Practice in Europe.

Journal of blood medicine·2026
Same author

Welcome to Spring 2026: Reflecting on a Transformative Year for <i>Bioconjugate Chemistry</i>.

Bioconjugate chemistry·2026
Same author

Influence of molecular shape and hydrogen bonding on glycolipid self-assembly into thermotropic gyroid phases.

Chemical science·2026
Same author

Hydroxypropyl cellulose/thermoplastic polyurethane blend films with reversible optical performance triggered by water.

Carbohydrate polymers·2026

Related Experiment Video

Updated: Sep 22, 2025

Assembly and Characterization of Polyelectrolyte Complex Micelles
08:44

Assembly and Characterization of Polyelectrolyte Complex Micelles

Published on: March 2, 2020

11.0K

Quantitation of Complexed versus Free Polymers in Interpolyelectrolyte Polyplex Formulations.

Xiaoling Wang1, Sneha S Kelkar1,2, Amanda G Hudson1

  • 1Department of Chemistry and Macromolecules and Interfaces Institute, Virginia Tech, Blacksburg, Virginia 24061, United States.

ACS Macro Letters
|May 18, 2022
PubMed
Summary
This summary is machine-generated.

Quantifying free polymer in polymer/DNA complexes (polyplexes) is crucial for gene delivery. A new NMR method accurately measures unbound polymer and polyplexes, optimizing formulation efficiency.

More Related Videos

Gene-therapy Inspired Polycation Coating for Protection of DNA Origami Nanostructures
08:30

Gene-therapy Inspired Polycation Coating for Protection of DNA Origami Nanostructures

Published on: January 19, 2019

9.3K
Controlled Synthesis and Fluorescence Tracking of Highly Uniform PolyN-isopropylacrylamide Microgels
11:34

Controlled Synthesis and Fluorescence Tracking of Highly Uniform PolyN-isopropylacrylamide Microgels

Published on: September 8, 2016

10.4K

Related Experiment Videos

Last Updated: Sep 22, 2025

Assembly and Characterization of Polyelectrolyte Complex Micelles
08:44

Assembly and Characterization of Polyelectrolyte Complex Micelles

Published on: March 2, 2020

11.0K
Gene-therapy Inspired Polycation Coating for Protection of DNA Origami Nanostructures
08:30

Gene-therapy Inspired Polycation Coating for Protection of DNA Origami Nanostructures

Published on: January 19, 2019

9.3K
Controlled Synthesis and Fluorescence Tracking of Highly Uniform PolyN-isopropylacrylamide Microgels
11:34

Controlled Synthesis and Fluorescence Tracking of Highly Uniform PolyN-isopropylacrylamide Microgels

Published on: September 8, 2016

10.4K

Area of Science:

  • Biomaterials Science
  • Analytical Chemistry
  • Gene Delivery Systems

Background:

  • Free polymer content in polyplex formulations significantly influences gene transfection, cellular uptake, and toxicity.
  • Accurate quantification of polyplex composition is essential for optimizing these formulations.

Purpose of the Study:

  • To develop and validate a facile Nuclear Magnetic Resonance (NMR) method for quantifying the composition of interpolyelectrolyte polyplex formulations.
  • To determine the effective binding ratio of polyethyleneimine (PEI) and DNA in polyplexes.

Main Methods:

  • Utilized 1D 1H NMR spectroscopy with a broad spectral width for precise integration.
  • Quantified unbound polymer and polyplexes in solution.
  • Validated NMR findings with isothermal titration calorimetry (ITC).

Main Results:

  • A polymer/DNA (polyplex) formulation with an initial N/P ratio of 5 showed an effective binding N/P ratio of 3.5.
  • No excess free polymer was detected in the optimized formulation.
  • The NMR method demonstrated strong agreement with ITC results.

Conclusions:

  • The developed NMR method provides a noninvasive and facile approach for quantifying polyplex composition.
  • This technique is broadly applicable to various polyelectrolyte coacervates.
  • Offers new opportunities for understanding and optimizing polyelectrolyte complex formation and quantitation.