cccDNA Purification Kit (100)-220502

Fast, non-enzymatic isolation of covalently closed circular DNA (cccDNA) from total DNA samples. Ideal for HBV studies, circulating eccDNA profiling, and cancer biomarker research. 100 preps/kit. For research use only.

Description

Covalently closed circular DNA (cccDNA) is the natural form of most plasmids. It is also a key replicative intermediate in the life cycles of certain viruses, such as hepatitis B virus (HBV). In higher organisms, including humans, cccDNA-like structures are referred to as extrachromosomal circular DNA (eccDNA). These molecules have been shown to play roles in eliciting innate immune responses, mediating cell-to-cell communication, promoting genetic heterogeneity, compensating for genetic loss, contributing to aging, regulating gene expression, and functioning as molecular sponges. Additionally, cell-free eccDNAs circulating in bodily fluids have emerged as potential biomarkers for the diagnosis and prognosis of various cancers.

The isolation of cccDNA from non-cccDNA is critical for studying its biological functions. Various isolation methods have been reported. Several techniques exploit the structural differences between chromosomal and circular DNA, enabling their separation via SDS lysis–salt precipitation or high-speed ultracentrifugation in cesium chloride gradients.

Most protocols involve total DNA extraction followed by multiple rounds of enzymatic digestion to eliminate non-cccDNA, and a final step of cccDNA purification. Enzymes used include:

• Exonuclease III, which digests linear and open circular forms of DNA

• Plasmid-Safe DNase, which preferentially hydrolyzes double-stranded linear DNA (dslDNA), and to a lesser extent, linear and closed circular single-stranded DNA (ssDNA)

• A combination of Exonuclease I and Exonuclease III, which degrade DNA strands with free 3′ ends

• T5 Exonuclease, which specifically digests nicked double-stranded circular DNA

This product is designed to purify cccDNA from either total DNA samples or partially purified preparations, offering a streamlined, enzyme-free workflow.

Features

• No Enzymatic Digestion Required — avoids DNA degradation from residual nucleases

• One-Step Extraction Protocol — time-saving and user-friendly

• High cccDNA Recovery Efficiency — minimal contamination with non-circular forms

• Broad Compatibility — suitable for cccDNA of all sizes

• Flexible Format — compatible with silica-based columns and magnetic bead systems

• 100 Preparations per Kit

• For Research Use Only

Applications

• HBV Research: Isolation of HBV cccDNA from infected liver tissues or cell models

• Cancer Biomarker Discovery: Extraction of circulating eccDNA from plasma for diagnostic/prognostic research

• Aging and Genetic Heterogeneity Studies: eccDNA profiling in aging models and cancer cell lines

• Gene Expression and Molecular Sponging Research

• High-throughput DNA Structure Analysis

Kit Contents

Note: For greater convenience, cccDNA Extraction Solution B and cccDNA Precipitation Solution are included in the extended version (CAT# 220502), eliminating the need to prepare additional reagents separately.