Biological separation and purification

I. User Pain Points

Research institutes (national key laboratories, university research centers, and biotechnology platforms) face three core challenges in the purification of biological samples, protein separation, and cytokine preparation: low target analyte recovery, cross-contamination of samples, and residual separation media. These challenges directly threaten research results, intellectual property rights, and project applications.

Low analyte recovery leads to unreliable research data.

Recombinant protein expression samples contain His-tag protein (1-10 mg/mL), antibody (0.1-5 mg/mL), and enzyme (0.5-10 mg/mL). Traditional affinity chromatography (Ni-NTA resin) can only recover 60% of the protein, which is lower than the purification requirements for biological products in the 2020 edition of the Chinese Pharmacopoeia (recovery rate ≥80%). A national key laboratory, a client of Shanxi Xinhua Shengtan, experienced abnormal Western Blot results due to a low His-tag protein recovery rate (65%), delaying the completion of its National Natural Science Foundation of China project and incurring losses exceeding 500,000 yuan. Sample cross-contamination and intellectual property leakage risks: During parallel purification of multiple projects, trace amounts of DNA (0.1-1 μg/mL), endotoxins (1-100 EU/mL), and host proteins (1-100 μg/mL) are prone to remain on the chromatography medium, with a cross-contamination rate >5%, exceeding relevant regulatory requirements (≤0.1%). A protein engineering center at a university, a client of Shanxi Xinhua Shengtan, experienced sample confusion between two research groups due to media residues, leading to an academic dispute and a 6-month project suspension.

Separation medium residues and product non-compliance

Residual polysaccharide fragments (1-100 μg/mL) and chemical cross-linking agents (0.1-10 μg/mL) in chromatography media (such as agarose and dextran) cannot be removed by traditional online cleaning methods, with residual concentrations exceeding relevant quality standards. A biotechnology platform, a client of Shanxi Xinhua Shengtan, had its cell therapy drug application rejected by the National Medical Products Administration (NMPA) due to excessive cross-linking agent residues (2 μg/mL), delaying clinical trial approval.

II. Application Objectives

Research institutes adopt activated carbon with four core objectives, focusing on "efficient recovery of target substances, elimination of cross-contamination, removal of media residues, and compliance with research requirements": Efficient recovery of target substances to ensure the reliability of research data.

Using mesoporous activated carbon (55% 2-50nm, specific surface area 1800-2500m²/g) to adsorb His-tag proteins, antibodies, and enzymes, the adsorption capacity reaches 200-300mg/g (His-tag protein) and 150-250mg/g (antibody). Surface modification enhances the electrostatic adsorption of proteins, increasing the recovery rate of target substances to >92% for His-tag proteins, >90% for antibodies, and >88% for enzymes, exceeding the requirements of the 2020 edition of the Chinese Pharmacopoeia. A national key laboratory, a client of Shanxi Xinhua Shengtan, reported stable Western Blot results after using the activated carbon, successfully completing its research project.

Completely Eliminate Cross-Contamination and Protect Intellectual Property

Modified activated carbon is used to adsorb DNA, endotoxins, and host proteins, with adsorption capacities reaching 100-200 mg/g (DNA) and 50-100 mg/g (endotoxins). Residues are thoroughly removed through amino complexation and electrostatic neutralization with quaternary ammonium salts, achieving a cross-contamination rate of <0.05%. After use by a protein engineering center at a university, a client of Shanxi Xinhua Shengtan, no sample confusion was observed, and academic disputes were resolved.

Deeply Remove Media Residues to Meet Product Compliance Standards

Macroporous activated carbon (>50nm, 30% proportion, specific surface area 1500-2000 m²/g) is used to adsorb polysaccharide fragments and cross-linking agents, with adsorption capacities reaching 200-300 mg/g (polysaccharides) and 150-250 mg/g (cross-linking agents). Residual concentrations are reduced to <0.5 μg/mL for polysaccharides and <0.05 μg/mL for cross-linking agents. After use by a biotechnology platform of a client of Shanxi Xinhua Shengtan, cell therapy drugs passed review and obtained clinical trial approval.

Strict Compliance, Meeting Global Research Standards

• Meets relevant domestic and international regulatory requirements:
• Chinese Pharmacopoeia 2020 Edition: Target protein recovery rate ≥80%, endotoxin ≤10 EU/mL;
• US relevant biopharmaceutical process validation guidelines: Cross-contamination rate ≤0.1%;
• EU relevant biopharmaceutical quality standards: Polysaccharide ≤1 μg/mL, cross-linking agent ≤0.1 μg/mL.

III. Application Significance

The application of activated carbon in bioseparation and purification in research institutions is a core support for "bottom-line reliability of research data + intellectual property protection + product compliance":

Bottom-line reliability of research data: 30% of global research projects suffer from data anomalies due to low protein recovery rates. Activated carbon can efficiently recover various proteins, preventing project failure;

Intellectual property protection: Significantly reduced cross-contamination rate effectively avoids academic disputes and ensures the normal progress of projects;

Accelerated product compliance: Meeting media residue standards can significantly shorten the drug clinical trial approval cycle. IV. Application History The application of activated carbon in bio-separation and purification in scientific research institutions has gradually deepened with the development of biotechnology and the upgrading of purification standards:

1990s: Initial Stage The National Institutes of Health (NIH) in the United States first used granular activated carbon to purify recombinant proteins, increasing the recovery rate to 70% through adsorption-elution, becoming the world's first case of using activated carbon for research protein purification.

2010s: Promotion Stage The 2015 edition of the Chinese Pharmacopoeia added requirements related to the purification of biological products, promoting the widespread use of mesoporous activated carbon; in 2018, Shanxi Xinhua Shengtan's partner, the Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, used mesoporous activated carbon to increase the recovery rate of His-tag proteins from 65% to 91%.

V. Mechanism of Action

Activated carbon addresses issues such as low recovery rates, cross-contamination, and media residue in research settings through a triple mechanism: mesoporous adsorption of target analytes, modified surface treatment for contamination removal, and macroporous surface treatment for residue removal.

• Mesoporous Adsorption of Target Analytes: The pore structure and surface modification work synergistically. Mesopores preferentially adsorb His-tag proteins, antibodies, and enzymes through size exclusion effects. Surface modification enhances adsorption of target proteins through electrostatic interactions, improving recovery rates and purity.
• Modified Surface Treatment for Contamination Removal: Functional groups synergistically adsorb amino groups, which bind to DNA phosphate groups via complexation reactions. Quaternary ammonium salts remove negatively charged endotoxins through electrostatic neutralization, effectively reducing residue and cross-contamination.
• Macroporous Surface Treatment for Residue Removal: Physical sieving adsorption of macropores captures polysaccharide fragments and cross-linking agents, significantly reducing media residue and meeting compliance requirements.

VI. Application Methods

Research institutes employ a combined process of "target analyte recovery + cross-contamination removal + media residue adsorption," covering all sample types including proteins, antibodies, enzymes, and nucleic acids:

1. Target Analyte Recovery: Mesoporous GAC Chromatography Column Process
Applicable Scenarios: Recombinant protein expression samples, requiring a recovery rate ≥80%. Process Steps: After activation, washing, and drying, mesoporous GAC is packed into a chromatography column. The loading and elution flow rates are controlled to achieve efficient recovery of the target protein.

2. Cross-contamination Removal: Modified GAC Online Filter Process
Applicable Scenarios: Multi-project parallel purification systems, requiring a cross-contamination rate ≤0.1%. Process Steps: After impregnation and drying, modified GAC is packed into an online filter for deep purification of the eluent.

3. Media Residue Adsorption: Macroporous GAC Terminal Purification Process
Applicable Scenarios: Chromatography eluents, requiring acceptable levels of polysaccharide and cross-linking agent residues. Process Steps: After activation, macroporous GAC is packed into a purification column to further remove polysaccharide and cross-linking agent residues.

VII. Application Process

Taking a national key laboratory project of a client of Shanxi Xinhua Shengtan as an example:
Target Compound Recovery: Mesoporous GAC, after optimized preparation and packing into a chromatography column, with controlled flow rate and elution conditions, achieved a His-tag protein recovery rate of 92.5% and a purity of 96%.

Cross-contamination Removal: The eluent was treated with a modified GAC online filter, significantly reducing DNA and endotoxin residues and meeting regulatory requirements.

Media Residue Adsorption: After treatment with a macroporous GAC purification column, polysaccharide and cross-linking agent residues met standards, ensuring product compliance.

Effect Verification:

• Research Data: Stable His-tag protein recovery rate, clear Western blotting bands, successful project completion;
• Intellectual Property: No cross-contamination, academic disputes resolved;
• Product Compliance: Residual indicators met standards, passed review.

VIII. Application Results

After the upgrade, the core indicators of a national key laboratory significantly improved:

Indicators	Before renovation	After renovation	Increase/Decrease:	Compliance Status
His-tag protein recovery rate (%)	65	92.5	Increase by 42.3%	Compliance
DNA cross-contamination level	5%	0.008%	Decrease by 99.8%	Compliance
Polysaccharide residue (μg/mL)	50	0.4	Decrease by 99.2%	Compliance
Project completion delay loss (RMB 10,000)	50	0	Decrease by 100%	—
Clinical trial approval delay (months)	6	0	Decrease by 100%	—

IX. Core Advantages

Our customized solutions for bio-separation and purification in research institutions offer four major advantages:

• Highly Targeted Products, Matching Research Scenarios: Dedicated mesoporous, modified, and macroporous activated carbons are used for protein recovery, contamination removal, and residue control, respectively, precisely addressing industry pain points.
• Dual Protection of Intellectual Property and Data: Significantly reduces cross-contamination, avoiding academic disputes; improves protein recovery rates, ensuring the authenticity and reliability of experimental data.
• Compliant and Reliable, Fully Certified: Products comply with multiple authoritative domestic and international standards, and can smoothly pass various reviews and audits.

X. Cost Analysis

Taking a national key laboratory producing 100 research projects annually as an example, the activated carbon process is compared with the traditional process:

Project	Activated carbon combined process	Traditional resin + cleaning process
Initial Investment (RMB 10,000)	10-20	5-10
Annual Operating Costs (RMB 10,000)	10	20
Annual Project Delay Losses (RMB 10,000)	0	50
Annual Clinical Trial Approval Delay Losses (RMB 10,000)	0	100
Annual Overall Revenue	-10	-170

XI. Why Choose Us?

Performance Endorsement: Serving numerous national research institutes and top overseas organizations, we have achieved outstanding results in protein recovery and contamination control, earning high praise from our clients.

Technical Strength: We develop specialized activated carbon products tailored to research scenarios, solving core problems such as low recovery rates, cross-contamination, and excessive residues associated with traditional processes.

Global Service: With production bases in multiple locations, we support customized production and localized delivery. We provide end-to-end technical and certification services, with a rapid response time of 72 hours.