Berberine hydrochloride co-crystal, preparation method and application thereof

Abstract

The application relates to a preparation method and application of a berberine hydrochloride-protocatechuic acid pharmaceutical co-crystal, and belongs to the field of pharmaceutical co-crystals. The berberine hydrochloride pharmaceutical co-crystal takes berberine hydrochloride as a pharmaceutical active ingredient and protocatechuic acid as a co-crystal former, and is obtained through a suspension crystallization method. Berberine hydrochloride and protocatechuic acid form the basic structural unit of the co-crystal through hydrogen bonds in a 1:1 stoichiometric ratio. The prepared berberine hydrochloride co-crystal can improve the solubility of berberine hydrochloride and improve the antibacterial capacity. The preparation process is simple, easy to control, mild in conditions, good in reproducibility, low in cost, and suitable for industrialized production.

Description

Technical Field

[0001] This invention belongs to the field of pharmaceutical cocrystallization technology, specifically relating to a berberine hydrochloride cocrystallization, its preparation method, and its application. Background Technology

[0002] Drug cocrystals typically consist of the active pharmaceutical ingredient (API) and cocrystal forming factor (CCF). The component molecules are bonded together through non-covalent interactions such as hydrogen bonds, van der Waals forces, and π-π stacking to form the cocrystal. Preparation methods for drug cocrystals are mainly divided into solid-state and solution-based methods, including solid-state milling, hot-melt extrusion, evaporation crystallization, cooling crystallization, reactive cocrystallization, and suspension crystallization. Drug cocrystallization technology can improve the physicochemical properties of drugs by altering the spatial stacking of crystals without destroying the structure of the active drug molecules, thereby improving solubility, dissolution behavior, and stability, and further enhancing bioavailability. In recent years, drug cocrystallization has received widespread attention as an effective strategy for optimizing drug performance.

[0003] Berberine hydrochloride (BBR, commonly known as "Huangliansu") is an isoquinoline alkaloid hydrochloride extracted from plants such as Coptis chinensis and Phellodendron amurense. It has a long history of medicinal use, possessing antihypertensive, anticancer, antibacterial, and anti-inflammatory effects. It is commonly used to treat intestinal infections and bacterial dysentery, and also has some inhibitory effects on influenza viruses and amoebae. However, berberine hydrochloride is only slightly soluble in water, has poor oral absorption, and low bioavailability (<1%), limiting its further clinical development and application. To improve this, researchers have developed various formulation strategies, such as organic acid salts (berberine fumarate, berberine succinate, etc.), nano-formulations, and cyclodextrin inclusion complexes. However, these methods each have limitations, and most are currently still in the laboratory research or preclinical stages; few improved formulations have been successfully marketed and widely used in clinical practice. Finding a balance between improving bioavailability, ensuring safety, reducing costs, and achieving industrial production remains a major challenge in the research of berberine hydrochloride formulations.

[0004] Berberine hydrochloride has aromatic nitrogen-containing groups, methoxy groups, etc., which can easily form hydrogen bonds or generate CH-π, π-π and other interactions with eutectic formations (CCF). This can change its physicochemical properties without affecting the pharmacological properties of the drug, providing a new method to solve the application problems of berberine hydrochloride. Summary of the Invention

[0005] The technical problem to be solved by this invention is to provide a berberine hydrochloride cocrystal, its preparation method, and its application. The provided cocrystal compound can improve the solubility of berberine hydrochloride and enhance its bioavailability.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] This invention provides a berberine hydrochloride cocrystal, comprising the following raw materials: berberine hydrochloride, an active pharmaceutical ingredient (API), and protocatechuic acid (PCA), also known as 3,4-dihydroxybenzoic acid, a naturally occurring phenolic acid, as a cocrystal forming product (CCF); wherein the molar ratio of berberine hydrochloride to protocatechuic acid is 1:1.

[0008] The structure of berberine hydrochloride (BBR) is shown in Formula I; the structure of protocatechuic acid (PCA) is shown in Formula II.

[0009] Formula I

[0010] Formula II

[0011] The powder X-ray diffraction (PXRD) pattern of the berberine hydrochloride-protocatechuic acid eutectic exhibits characteristic diffraction peaks at diffraction angles 2θ of 9.70°±0.2, 17.25°±0.2, 18.89°±0.2, 19.57°±0.2, 23.00°±0.2, 24.19°±0.2, 26.00°±0.2, and 28.52°±0.2.

[0012] The molecular formula of the berberine hydrochloride-protocatechuic acid eutectic is C1. 20 H 18 ClNO4·C7H6O4, berberine hydrochloride and protocatechuic acid are bonded together in a 1:1 stoichiometric ratio via hydrogen bonds to form the basic structural unit of this eutectic. Berberine hydrochloride (BBR) acts as a hydrogen bond donor, and protocatechuic acid (PCA) acts as a hydrogen bond acceptor. The two interact through hydrogen bonds to form a stable eutectic structure.

[0013] The differential scanning calorimetry (DSC) spectrum of the berberine hydrochloride-protocatechuic acid eutectic showed an endothermic peak at 231.17 °C.

[0014] The method for preparing the berberine hydrochloride eutectic is to use a suspension crystallization method of berberine hydrochloride and protocatechuic acid.

[0015] Preferably, protocatechuic acid is dissolved in ethanol as a co-crystal former, and berberine hydrochloride, the active pharmaceutical ingredient, is added. After stirring and suspending, a co-crystal is formed through hydrogen bonding and other forces.

[0016] Preferably, in this embodiment, the molar ratio of berberine hydrochloride to protocatechuic acid is 1:1.

[0017] The suspension method is magnetic stirring at a speed of 200-400 rpm.

[0018] The stirring temperature is 25-37℃.

[0019] The berberine hydrochloride-protocatechuic acid eutectic prepared by this invention can improve the solubility and dissolution rate of berberine hydrochloride, improve bioavailability, enhance antioxidant capacity, and better exert its therapeutic effect.

[0020] The method for preparing berberine hydrochloride-protocatechuic acid eutectic of the present invention is simple, reproducible, and the preparation conditions are mild, easy to control, and easy to achieve large-scale industrial production. Attached Figure Description

[0021] Figure 1 The Fourier transform infrared (FTIR) spectrum of the berberine hydrochloride-protocatechuic acid eutectic in Example 1 is shown.

[0022] Figure 2 This is the powder X-ray diffraction (PXRD) pattern of the berberine hydrochloride-protocatechuic acid eutectic in Example 1.

[0023] Figure 3 The 1H NMR spectrum of the berberine hydrochloride-protocatechuic acid eutectic in Example 1 (… 1 (HNMR) image.

[0024] Figure 4 This is a differential scanning calorimetry (DSC) chromatogram of the berberine hydrochloride-protocatechuic acid eutectic in Example 1.

[0025] Figure 5 This is a solubility diagram of the berberine hydrochloride-protocatechuic acid eutectic in pure water in Example 2.

[0026] Figure 6 This is a dissolution curve of berberine hydrochloride-protocatechuic acid cocrystal in PBS buffer at pH 7.4 in Example 3.

[0027] Figure 7 The graph shows the ABTS scavenging rate of the berberine hydrochloride-protocatechuic acid eutectic in Example 4.

[0028] Figure 8 This is a diagram showing the diameter of the inhibition zone of the berberine hydrochloride-protocatechuic acid eutectic in Example 5. Detailed Implementation

[0029] The technical solution of the present invention will be described in detail below with reference to specific embodiments. The following embodiments are only used to better explain the principles and features of the present invention and are not intended to limit the scope of the present invention.

[0030] Example 1

[0031] Preparation of eutectic of berberine hydrochloride-protocatechuic acid

[0032] Weigh 0.0925 g of protocatechuic acid and 0.2231 g of berberine hydrochloride (molar ratio 1:1), add to 10 mL of ethanol, stir at 300 rpm for 36 h in the dark at room temperature, filter under reduced pressure, and dry to constant weight in the dark at 25 ℃ to obtain berberine hydrochloride-protocatechuic acid eutectic (BBR-PCA).

[0033] The berberine hydrochloride-protocatechuic acid eutectic prepared in Example 1 was analyzed by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), and proton nuclear magnetic resonance spectroscopy (NMR). 1 Characterization was performed using 1H NMR and differential scanning calorimetry (DSC). The specific process is as follows:

[0034] (1) Fourier transform infrared characterization of berberine hydrochloride-protocatechuic acid eutectic

[0035] Fourier transform infrared (FTIR) characterization was performed using a Nicolet 6700 FTIR spectrometer (Thermo Fisher Scientific, USA) employing the KBr pellet transmission method. The measurement range was 4000–500 cm⁻¹.

[0036] Fourier transform infrared spectrum as follows Figure 1 As shown, the berberine hydrochloride-protocatechuic acid eutectic crystals were observed at 3482 cm⁻¹. -1 1642 cm -1 1551 cm -1 The presence of characteristic peaks indicates a change in the relative concentrations of berberine hydrochloride and protocatechuic acid, suggesting a change in the local chemical environment and the presence of hydrogen bonds between BBR and PCA, resulting in the formation of a new phase.

[0037] (2) X-ray diffraction identification of berberine hydrochloride-protocatechuic acid eutectic powder

[0038] Powder X-ray diffraction (PXRD) was performed using a Rigaku MiniFlex 600 diffractometer (Rigaku, Japan). The scanning range was 5–50 ° with a step size of 0.010 °, the X-ray tube operating voltage was 40 kV, and the current was 15 mA.

[0039] Powder X-ray diffraction pattern as shown Figure 2 As shown, the berberine hydrochloride-protocatechuic acid eutectic exhibits new diffraction peaks at 2θ values ​​of 9.70°±0.2, 17.25°±0.2, 18.89°±0.2, 19.57°±0.2, 23.00°±0.2, 24.19°±0.2, 26.00°±0.2, and 28.52°±0.2, indicating the formation of a new crystalline phase.

[0040] (3) 1H NMR spectrum analysis of berberine hydrochloride-protocatechuic acid eutectic

[0041] Nuclear magnetic resonance spectroscopy (NMR) 1 H NMR was performed on an AVANCE 400 spectrometer (Bruker BioSpin, Switzerland). BBR, PCA, and the eutectic were dissolved in DMSO-d6 or D2O and pulsed using a zg30 pulse program (30 ° single pulse).

[0042] Nuclear magnetic resonance hydrogen spectrum as follows Figure 3 As shown, eutectic 1 The ¹H NMR spectrum of the berberine hydrochloride-protocatechuic acid eutectic contains two chemical components: berberine hydrochloride and protocatechuic acid. The molar ratio of BBR to PCA in the eutectic was determined to be 1:1 using the hydrogen integral method.

[0043] (4) Differential scanning calorimetry of berberine hydrochloride-protocatechuic acid eutectic

[0044] Differential scanning calorimetry (DSC) was performed on a DSC 3 instrument (Mettler Toledo, Switzerland) under an argon atmosphere, with a sample measurement range of 0-280 °C and a heating rate of 10 °C / min.

[0045] Differential scanning calorimetry (DSC) Figure 4 As shown, the berberine hydrochloride-protocatechuic acid eutectic exhibits a characteristic melting peak at 231.17 ℃, while berberine hydrochloride and protocatechuic acid exhibit melting peaks at 193.17 ℃ and 205.83 ℃, respectively. The melting peak of the berberine hydrochloride-protocatechuic acid eutectic is significantly elevated, indicating that the thermal stability of berberine hydrochloride is improved after the formation of the eutectic.

[0046] Example 2

[0047] Determination of the solubility of berberine hydrochloride eutectic in pure water

[0048] Solubility was determined using the shake-flask method. Standard curves of berberine hydrochloride in pure water were measured at 25 °C and 37 °C, respectively. Excess of each sample was added to 5 mL of ultrapure water or anhydrous ethanol, and the mixture was shaken at 200 rpm for 36 hours at 25 °C or 37 °C to reach equilibration. The equilibration supernatant was collected and filtered through a 0.45 μm membrane filter. Solubility was analyzed by measuring the absorbance at characteristic wavelengths of berberine hydrochloride at 25 °C and 37 °C using a microplate reader.

[0049] Solubility in pure water as Figure 5 As shown, the solubility of berberine hydrochloride-protocatechuic acid eutectic at 25 ℃ and 37 ℃ is approximately 2.74 times and 2.77 times that of berberine hydrochloride, respectively. The berberine hydrochloride-protocatechuic acid eutectic increases the solubility of berberine hydrochloride.

[0050] Example 3

[0051] Determination of the dissolution behavior of berberine hydrochloride-protocatechuic acid cocrystal in PBS buffer at pH 7.4

[0052] Dissolution behavior was determined in PBS buffer (pH 7.4). 10 mL of PBS buffer, preheated to 37 °C, was placed in a centrifuge tube, and excess berberine hydrochloride, protocatechuic acid, or berberine hydrochloride-protocatechuic acid eutectic powder was added to ensure saturation. After sealing, the tube was shaken at 200 rpm at 37 °C, and samples were collected at 5, 10, 15, 20, 30, 45, 60, 90, 120, and 240 minutes. Each sample was centrifuged at 12,000 rpm for 5 minutes, and the supernatant was collected and diluted as necessary. The concentration was determined using the characteristic wavelength of berberine hydrochloride, and the sample concentration was calculated using an established standard curve.

[0053] The dissolution curve of the pH 7.4 buffer solution is as follows: Figure 6 As shown, the curve of berberine hydrochloride-protocatechuic acid eutectic is generally higher than that of berberine hydrochloride. At equilibrium, the concentration of dissolution does not drop significantly relative to the highest concentration of dissolution, indicating that the dissolution behavior is improved.

[0054] Example 4

[0055] Determination of ABTS scavenging rate in berberine hydrochloride-protocatechuic acid eutectic

[0056] The antioxidant capacity of the samples was assessed using ABTS radical scavenging. The antioxidant reduced ABTS·⁺ to the colorless original ABTS (reduced state), and the solution color gradually lightened from blue-green. Berberine hydrochloride, protocatechuic acid, and berberine hydrochloride-protocatechuic acid cocrystal were added to 96-well plates, with vitamin C as a positive control. After mixing the samples with the ABTS·⁺ solution, the mixture was incubated under light-protected conditions, and the absorbance was measured at 734 nm.

[0057] ABTS clearance rate Figure 8 As shown, at concentrations of 20, 40, and 80 μg / mL, the ABTS scavenging efficiencies of the berberine hydrochloride-protocatechuic acid cocrystal were approximately 38.6%, 60.0%, and 87.0%, respectively, while the scavenging rates of berberine hydrochloride were 24.23%, 33.56%, and 47.32%. The scavenging rate of the cocrystal was significantly higher than that of berberine hydrochloride, indicating that the BBR-PCA cocrystal improved the antioxidant capacity.

[0058] Example 5

[0059] Antibacterial activity assessment of berberine hydrochloride-protocatechuic acid eutectic

[0060] Antibacterial activity was assessed using the Oxford cup method, which was used to test Escherichia coli (E. coli). Escherichia coliThe culture medium was inoculated with berberine hydrochloride, protocatechuic acid, and berberine hydrochloride-protocatechuic acid cocrystals at concentrations of 2 mg / mL, 4 mg / mL, and 6 mg / mL, respectively. The antibacterial activity was assessed by evaluating the diameter of the inhibition zone.

[0061] The diameter of the inhibition zone is as follows Figure 7 As shown, the antibacterial activity of the berberine hydrochloride-protocatechuic acid cocrystal at concentrations of 2 mg / mL, 4 mg / mL, and 6 mg / mL was approximately 1.38 times, 1.21 times, and 1.10 times that of berberine hydrochloride, respectively. All concentrations were higher than those of berberine hydrochloride, indicating that the cocrystal exhibited superior antibacterial activity.

Claims

1. A berberine hydrochloride eutectic, characterized in that, Berberine hydrochloride is the active pharmaceutical ingredient, and protocatechuic acid is the eutectic form, which is formed in a 1:1 molar ratio.

2. The berberine hydrochloride-protocatechuic acid eutectic according to claim 1, characterized in that... The berberine hydrochloride-protocatechuic acid eutectic exhibits characteristic peaks in its powder X-ray diffraction pattern at diffraction angles 2θ of 9.70°±0.2, 17.25°±0.2, 18.89°±0.2, 19.57°±0.2, 23.00°±0.2, 24.19°±0.2, 26.00°±0.2, and 28.52°±0.

2.

3. The eutectic according to claim 1, characterized in that... The infrared spectrum of berberine hydrochloride-protocatechuic acid co-crystal has characteristic peaks at 3482 cm -1 , 1642 cm -1 , 1551 cm -1 .

4. The method for preparing berberine hydrochloride-protocatechuic acid eutectic according to claim 1, characterized in that, Berberine hydrochloride and protocatechuic acid were added to ethanol, stirred at room temperature, filtered, and dried to prepare a cocrystal of berberine hydrochloride and protocatechuic acid.

5. The preparation method according to claim 4, characterized in that, The suspension crystallization method is magnetic stirring, with a stirring speed of 200-400 rpm, a suspension temperature of 25-37℃, and a stirring time of 36-48 h.

6. The application of the berberine hydrochloride-protocatechuic acid eutectic according to any one of claims 1-5 in the field of pharmaceutical preparation.

7. A pharmaceutical composition, characterized in that, It comprises the berberine hydrochloride-protocatechuic acid eutectic as described in any one of claims 1-3.

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