Rubescens A test standard - Huaqiang Electronic Network

Properties: This product is a white crystalline powder; it is odorless and has a special odor.

Properties: This product dissolves in solvents such as methanol, ethanol, and acetone. It is slightly soluble in solvents like petroleum ether and hardly soluble in water.

Test: Take 10 mg of this product, add 10 ml of methanol, dissolve completely, and the solution should be clear, colorless, or slightly yellow.

Melting point: Dry the product using phosphorus pentoxide as a desiccant under reduced pressure until constant weight is achieved. Then measure the melting point range using the capillary method.

248°C - 250°C (Chinese Pharmacopoeia, 2005 Edition, Appendix VII C).

Loss on drying: Dry the product with phosphorus pentoxide under reduced pressure to constant weight. The loss on drying should not exceed 3% (Chinese Pharmacopoeia, 2005 Edition, Appendix IX G).

Determination of content: According to high-performance liquid chromatography (HPLC), as specified in the Chinese Pharmacopoeia, 2005 Edition, Appendix VI D. The normalization method should not be lower than 98%, and the external standard method should not be lower than 95%.

1. Chromatographic conditions:

Column: Hypersil C18, 5μm, 4.6mm × 250mm

Mobile phase: Methanol:Water = 60:40

Flow rate: 0.8 ml/min

Detection wavelength: 238 nm

2. Preparation of standard solutions:

Weigh 8 mg of Rubescens A reference substance accurately, place it in a 25 ml volumetric flask, add 15 ml of methanol, sonicate, cool to room temperature, then dilute to 25 ml. Shake well.

3. Preparation of test solution:

Weigh an equivalent amount of the test sample (8 mg of Rubescens A reference substance), place it in a 25 ml volumetric flask, add 15 ml of methanol, sonicate, cool to room temperature, and dilute to 25 ml. Shake well.

4. Determination:

Inject 15 μl of methanol into the HPLC for blank measurement. Then inject 15 μl of both the reference solution and the test solution. Record the peak areas of both the reference and the test sample.

5. Calculation:

Wx = (A1 × C2 × Ws) / (A2 × C1)

Where:

Wx – Test content

C1 – Test concentration

C2 – Reference concentration

A1 – Peak area of test sample

A2 – Peak area of reference

Ws – Reference content

98% (Our company)

About Qingyun:

Nanjing Qingyun Biotechnology Co., Ltd. is located in Nanjing, the ancient capital of the Six Dynasties. The company specializes in the production, sales, and service of plant extracts, active ingredient monomers, and plant raw powders. With a team of experts in phytochemistry, traditional Chinese medicine, biotechnology, and modern analytical techniques, we are committed to providing high-quality products and services.

Qingyun Biological Ordering Instructions:

1. Order via phone, QQ, or other methods. When placing an order, please inform the salesperson of the product name, quantity, and specifications.

2. Same-day payment processing is available. In case of special needs, invoices can be issued for reimbursement purposes.

3. Product advantages include efficient technology, stable supply chain, and a professional sales team.

4. Standard packaging is available. Custom packaging is also possible upon request.

5. Quality assurance: Strict quality control. If any quality issues are confirmed through our company, returns are accepted without conditions.

6. Storage: Keep sealed and away from light.

Qingyun Biological Service:

1. Custom R&D and production of chemical active ingredients and standard products for traditional Chinese medicine.

2. Development of industrialized high-efficiency separation and purification processes for herbal medicine chemical components and high-concentration extracts.

3. Production of natural product APIs and intermediates, including custom synthesis and semi-synthesis.

4. Custom research and development and production of traditional Chinese medicine extracts.