Liposome Drug Encapsulation Efficiency Measurement

As an undisputed global leader in the development and manufacturing of liposome drug delivery, BOC Sciences can provide reliable analytical services to quantify the encapsulation efficiency of different drug carriers.

Why Analyze the Packaging Efficiency?

Encapsulation efficiency is one of the important parameters for assessing the success of a drug delivery system.
Encapsulation efficiency is an expression of the amount of drug incorporated into liposomes and is generally defined as the percentage of drug bound to liposomes relative to the total amount of drug.

Factors Affecting Packaging Efficiency

• Partition coefficient of the target molecule in the solvent used in the preparation of the formulation
• Method of encapsulation process (temperature, pH, ionic strength, mechanical stress, etc.)
• Size distribution of liposomes

What We Provide?

We provide liposome encapsulation efficiency testing services using multiple analytical methods.

How We Test for the Encapsulation Efficiency?

• The first step is to separate the unpackaged drug from the liposomes. We use fast and simple separation methods, such as centrifugation to avoid excessive dilution of samples and to prevent liposome rupturing that could result in premature drug release. We will then use high-performance liquid chromatography（HPLC）combined with molecular exclusion chromatography to measure the drug encapsulation efficiency.
• Fluorescent stain assay is an effective approach for nucleic acid quantification. We add the test sample in kit, incubate and monitor the fluorescence intensity to calculate the encapsulation efficiency.

Figure 1: Schematic of the separation and extraction processes (Ohnishi, N. 2013).

Contact us for a free consultation to design and customize an analytical method for your liposome drug molecule.

FAQs

What's the difference between packaging efficiency and loading?

The encapsulation efficiency (EE%) is obtained by dividing the total amount of added drug-free non-retentive drugs by the total amount of added drug.
The loading is the amount of drug-loaded per unit weight of the nanoparticle, indicating the mass percentage of the nanoparticle due to the encapsulated drug. The loading capacity (LC%) can be calculated by dividing the total amount of drug retained by the total weight of the nanoparticles.
In drug delivery, the yields given as percentages reflect the amount of drug delivered per encapsulated amount.

References

1. Yamamoto E. et al. A simple and rapid measurement method of encapsulation efficiency of doxorubicin loaded liposomes by direct injection of the liposomal suspension to liquid chromatography. Int J Pharm. 2018 Jan 30; 536(1):21-28.
2. Sandy Gim Ming Ong. et al. Influence of the Encapsulation Efficiency and Size of Liposome on the Oral Bioavailability of Griseofulvin-Loaded Liposomes. Pharmaceutics. 2016 Sep; 8(3): 25.
3. Hwang SY. et al. Effects of operating parameters on the efficiency of liposomal encapsulation of enzymes. Colloids Surf B Biointerfaces. 2012 Jun 1; 94:296-303.
4. Ohnishi, N. et al. Rapid determination of the encapsulation efficiency of a liposome formulation using column-switching HPLC. International Journal of Pharmaceutics. 2013; 441(1-2):67–74.