A kind of piperine starch nanoparticles and preparation method thereof

Abstract

The present invention discloses a piperine starch nanoparticle and a preparation method thereof. The preparation method of the piperine starch nanoparticle of the present invention is simple to operate, highly repeatable, has low energy consumption, is easy to industrialize, and does not require the introduction of a large amount of solvent during the preparation process, thus avoiding problems such as solvent residue or solvent contamination. The piperine starch nanoparticles prepared by the preparation method of the present invention have a small average particle size and are uniformly distributed. The crystal form of piperine is complete, and the original crystalline properties remain unchanged. That is, the obtained piperine starch nanoparticles still retain the pharmacological activity of piperine. The cumulative release amount in simulated gastrointestinal fluid is significantly improved compared to pure piperine, which is beneficial to the bioavailability of piperine. In addition, the piperine starch nanoparticles prepared by the present invention have high redispersibility and good stability. After being redissolved to prepare a suspension, they can also remain in a suspended state for a long time. The particle size distribution is uniform, and they are not easy to aggregate or settle, making them more suitable for long-term storage.

Description

Technical Field

[0001] The present invention belongs to the field of biomedicine technology and more specifically relates to piperine starch nanoparticles and a preparation method thereof. Background Art

[0002] Piperine is the most abundant amide alkaloid in the Piper nigrum L. plant of the Piperaceae family. It not only imparts a spicy flavor to food but is also the primary pharmacologically active ingredient in pepper. Piperine exhibits numerous physiological functions, including analgesia, antiasthma, antibacterial, anti-inflammatory, hypoglycemic, tumor prevention, and treatment of convulsions, depression, gastric ulcers, epilepsy, atherosclerosis, and brain function. It possesses significant adjuvant and regulatory effects and is widely used in the food and pharmaceutical industries. Researchers have conducted in-depth studies on the chemical composition and pharmacological effects of piperine, including its effects on immune function, the central nervous system, and cardiovascular and cerebrovascular functions. These studies have revealed promising prospects for the development of piperine, potentially expanding its clinical applications. With the advancement of modern science and the increasing appreciation of its role in medicine and healthcare, piperine's role in promoting nutrient absorption and enhancing bioavailability has also garnered significant attention.

[0003] Although piperine has a broad application prospect, its molecular structure contains benzene rings, olefins, carbonyl groups and other hydrophobic groups, which cause piperine to have lipophilicity, low water solubility and low solubility. It is often unable to fully dissolve in the gastrointestinal tract, is difficult to be digested and absorbed by the human body, has low bioavailability, and only a small amount of piperine can achieve its pharmacological activity. In order to improve the bioavailability of piperine and optimize its therapeutic effect and clinical application, various solubilization systems have been developed to improve the solubility and dissolution rate of piperine, including inclusion / coating technology, solid dispersion technology, microemulsion technology, liposome technology and nanotechnology. Higher dissolution rate can increase the release of piperine from its composition, which is a prerequisite for piperine to have sufficient bioavailability. However, the above-mentioned solubilization systems generally have low drug loading, poor physical stability, high energy consumption, complicated operation conditions and the need to introduce a large amount of solvents, resulting in shortcomings such as solvent residue or solvent contamination. Therefore, it is necessary to provide a piperine solubilization system with low energy consumption and a preparation process that does not require the introduction of a large amount of solvents, and to construct a corresponding preparation method so that the solubility and physical stability of piperine are improved. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the defects and shortcomings of the above-mentioned existing technologies and provide a piperine starch nanoparticle and a preparation method thereof.

[0005] The first object of the present invention is to provide a piperine starch nanoparticle.

[0006] The second object of the present invention is to provide a method for preparing the piperine starch nanoparticles.

[0007] The above-mentioned purpose of the present invention is achieved through the following technical solutions:

[0008] The invention provides a piperine starch nanoparticle. The nanoparticle is prepared from piperine and a stabilizer in a mass ratio of 1 to 4:1 to 4.

[0009] Optionally, the stabilizer is octenyl succinate starch, hydroxypropyl methylcellulose or polyvinyl pyrrolidone.

[0010] Preferably, the stabilizer is octenyl succinate starch. The piperine starch nanoparticles prepared using octenyl succinate starch have a smaller average particle size and better stability.

[0011] The average particle size of the piperine starch nanoparticles of the present invention is in the range of 50 to 300 nm. After being placed for 7 days, the average particle size is still less than 300 nm, and the particle size variation range is less than 100 nm.

[0012] Preferably, the average particle size of the piperine starch nanoparticles is ≤200 nm, the average particle size is still less than 300 nm after 7 days, and the particle size variation range is less than 100 nm; the piperine starch nanoparticles within this particle size range have higher stability and are more conducive to the absorption of piperine.

[0013] Further preferably, the particle size of the piperine starch nanoparticles is ≤100 nm, the average particle size is still less than 100 nm after 7 days, and the particle size variation range is less than 50 nm; the piperine starch nanoparticles within this particle size range have a lower average particle size, higher stability, and are more conducive to the absorption of piperine.

[0014] The present invention also provides a method for preparing the piperine starch nanoparticles, comprising the following steps:

[0015] S1. Under dark conditions, the formulated amount of piperine and stabilizer was added to primary water and stirred to obtain a pre-suspension;

[0016] S2. The pre-suspension obtained in step S1 was ground with zirconium oxide grinding beads, and the grinding beads were filtered to obtain a suspension of piperine starch nanoparticles;

[0017] S3. spraying or freeze-drying the piperine starch nanoparticle suspension obtained in step S2 to obtain solidified piperine starch nanoparticle powder, namely the piperine starch nanoparticles.

[0018] Specifically, in step S1, the amount of first-grade water is as follows: 200 mL of first-grade water is added for every 2-8 g of piperine and stabilizer.

[0019] Specifically, in step S1, the mass ratio of piperine to stabilizer is 1-4:1-4.

[0020] Preferably, in step S1, the mass ratio of piperine to stabilizer is 1:1-4.

[0021] Further preferably, in step S1, the mass ratio of piperine to stabilizer is 1:4.

[0022] Specifically, in step S1, the stirring speed is 250-350 rpm and the stirring time is 18-22 minutes. The main purpose of this process is to fully mix the piperine and the stabilizer to obtain a pre-suspension. In the present invention, the speed used is 300 rpm and the stirring time is 20 minutes.

[0023] Specifically, the grinding in step S2 is wet ball milling, and the ball milling speed is 300-500 rpm.

[0024] Preferably, the ball milling speed is 300-400 rpm.

[0025] More preferably, the ball milling speed is 300 rpm.

[0026] Specifically, the amount of the zirconium oxide grinding beads in step S2 is: 520-580 g of zirconium oxide grinding beads are added for every 2-8 g of piperine and stabilizer.

[0027] More specifically, the amount of zirconium oxide grinding beads used was 550 g.

[0028] Specifically, in step S2, the diameter of the zirconium oxide grinding beads is 0.1 to 1 mm.

[0029] Preferably, the diameter of the zirconium oxide grinding beads is 0.6 to 1 mm. When the diameter of the zirconium oxide grinding beads is 0.1 mm, the stability of the prepared piperine starch nanoparticles is relatively poor.

[0030] More preferably, the diameter of the zirconium oxide grinding beads is 0.6 mm.

[0031] Specifically, in step S2, the total grinding time is 40 to 120 minutes.

[0032] Alternatively, the total milling time may be 40, 60, 80, 100 or 120 minutes.

[0033] Preferably, the total grinding time is 60 to 120 minutes.

[0034] More preferably, the total grinding time is 120 minutes.

[0035] Specifically, in step S3, the sample is spray-dried.

[0036] Specifically, the spray drying conditions are: fan frequency 40-60 Hz, air inlet temperature 118-122° C., and pump speed 8-12%.

[0037] More specifically, the spray drying conditions are: fan frequency 50 Hz, inlet air temperature 120° C., and pump speed 10%.

[0038] The present invention also claims protection for the piperine starch nanoparticles prepared by the above method.

[0039] The present invention has the following beneficial effects:

[0040] The present invention provides piperine starch nanoparticles and a preparation method thereof. The preparation method of the piperine starch nanoparticles of the present invention is simple to operate, highly reproducible, has low energy consumption, and is easy to industrialize. Furthermore, the preparation process does not require the introduction of a large amount of solvent, thus avoiding problems such as solvent residue and solvent contamination. The piperine starch nanoparticles prepared using the preparation method of the present invention have a small average particle size and a uniform distribution. The crystal form of piperine is complete, and the original crystalline properties are unchanged. In other words, the obtained piperine starch nanoparticles still retain the pharmacological activity of piperine, but their cumulative release in simulated gastrointestinal fluid is significantly improved compared to pure piperine, which is beneficial for the bioavailability of piperine and overcomes the shortcomings of piperine's low solubility and poor physical stability, which only allow a small amount of piperine to achieve its pharmacological activity. Furthermore, the piperine starch nanoparticles prepared by the present invention have high redispersibility and good stability. After being redissolved to form a suspension, they can remain suspended for a long time. The particles have a low average particle size and a uniform particle size distribution, are less likely to aggregate or settle, and are more suitable for long-term storage. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 These are infrared spectra of spray-dried piperine starch nanoparticles, freeze-dried piperine starch nanoparticles, spray-dried piperine starch mixture, piperine starch mixture, spray-dried pure piperine nanoparticles and pure piperine.

[0042] Figure 2 These are the differential scanning calorimetry analysis results of spray-dried piperine starch nanoparticles, freeze-dried piperine starch nanoparticles, spray-dried piperine starch mixture, piperine starch mixture, spray-dried pure piperine nanoparticles and pure piperine.

[0043] Figure 3 These are the X-ray diffraction curves of spray-dried piperine starch nanoparticles, freeze-dried piperine starch nanoparticles, spray-dried piperine starch mixture, piperine starch mixture, spray-dried pure piperine nanoparticles and pure piperine.

[0044] Figure 4 This is the standard curve of piperine.

[0045] Figure 5 The results are the cumulative release amounts of piperine from spray-dried piperine starch nanoparticles, freeze-dried piperine starch nanoparticles, spray-dried piperine starch mixture, spray-dried piperine pure nanoparticles and piperine pure in simulated gastrointestinal fluid.

[0046] Figure 6 The states of pure piperine, a mixture of piperine and octenylsuccinate-esterified starch (1:4), a spray-dried piperine starch nanoparticle suspension, and a freeze-dried piperine starch nanoparticle suspension after 0, 7, and 30 days of sealed storage. DETAILED DESCRIPTION

[0047] The present invention will be further described below with reference to the accompanying drawings and specific examples, but the examples do not limit the present invention in any way. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art.

[0048] Unless otherwise specified, all reagents and materials used in the following examples were commercially available.

[0049] The piperine used in the examples of the present invention was purchased from Xi'an Ruilin Biotechnology Co., Ltd. with a CAS number of 94-62-2; octenyl succinate starch (HI-CAP100) was purchased from National Starch Industry (Shanghai) Co., Ltd. with a product number of HI-CAP100.

[0050] Example 1 Preparation of piperine starch nanoparticles

[0051] In this embodiment, the preparation method of piperine starch nanoparticles is as follows:

[0052] S1. Under dark conditions, 1g of piperine and 1g of octenyl succinate starch were added to 200mL of primary water and stirred at 300rpm for 20 minutes to obtain a pre-suspension;

[0053] S2. The pre-suspension was poured into a grinding jar containing 550 g of zirconia grinding beads with a diameter of 0.6 mm and ground at a ball mill speed of 300 rpm for 60 minutes. The grinding beads were filtered to obtain a suspension of piperine starch nanoparticles.

[0054] During the grinding process, a break was taken after every 5 minutes to prevent the sample from overheating.

[0055] The prepared piperine starch granule suspension was diluted an appropriate number of times, and the average particle size, PDI, and zeta potential (ζ-potential) of the particles were measured using a Zatasizer Nano ZS 90 dynamic light scattering nanoparticle size analyzer. Separately, the prepared piperine starch nanoparticle suspension was sealed and stored in the dark. After 7 days, the average particle size, PDI, and zeta potential of the particles were measured using a Zatasizer Nano ZS 90 dynamic light scattering nanoparticle size analyzer.

[0056] The average particle size of the piperine starch nanoparticles prepared in this example is 211±4nm, the PDI is 0.266±0.03, and the Zeta potential is -20±0.9kv. After being placed for 7 days, the average particle size is 250±7nm, the PDI is 0.314±0.03, and the Zeta potential is -19.1±0.8kv. It can be seen that the average particle size of the piperine starch nanoparticles prepared in this example is about 200nm, the PDI is small, the nanoparticle size distribution is uniform, the solution has good homogeneity, the Zeta potential is moderate, and the particle surface is negatively charged, which meets the requirements of nanoparticles; after being stored for 7 days, the average particle size is still less than 300nm, the PDI is less than 0.4, and the Zeta potential does not change much. The obtained piperine starch nanoparticles show good stability.

[0057] Example 2 Preparation of Piperine Starch Nanoparticles

[0058] In this embodiment, the preparation method of piperine starch nanoparticles is as follows:

[0059] S1. Under dark conditions, 1g of piperine and 1g of octenyl succinate starch were added to 200mL of primary water and stirred at 300rpm for 20 minutes to obtain a pre-suspension;

[0060] S2. The pre-suspension was poured into a grinding jar containing 550 g of zirconia grinding beads with a diameter of 0.6 mm and ground at a ball mill speed of 300 rpm for 40 minutes. The grinding beads were filtered to obtain a suspension of piperine starch nanoparticles.

[0061] During the grinding process, a break was taken after every 5 minutes to prevent the sample from overheating.

[0062] The same method as in Example 1 was used to measure the average particle size, PDI and Zeta potential of the obtained piperine starch nanoparticles at 0 day and after 7 days of storage.

[0063] The average particle size of the piperine starch nanoparticles prepared in this example is 272±1nm, PDI is 0.235±0.02, and Zeta potential is -22.7±0.3kv. After 7 days of storage, the average particle size is 298±5nm, PDI is 0.315±0.08, and Zeta potential is -21.6±0.4kv. It can be seen that the average particle size of the piperine starch nanoparticles prepared in this example is less than 300nm, PDI is less than 0.3, the nanoparticle size distribution is uniform, the solution homogeneity is good, the Zeta potential is moderate, and the particle surface is negatively charged, which meets the requirements of nanoparticles; after 7 days of storage, the average particle size is still less than 300nm, the Zeta potential does not change much, and the obtained piperine starch nanoparticles show good stability.

[0064] Example 3 Preparation of Piperine Starch Nanoparticles

[0065] In this embodiment, the preparation method of piperine starch nanoparticles is as follows:

[0066] S1. Under dark conditions, 1g of piperine and 1g of octenyl succinate starch were added to 200mL of primary water and stirred at 300rpm for 20 minutes to obtain a pre-suspension;

[0067] S2. The pre-suspension was poured into a grinding jar containing 550 g of zirconia grinding beads with a diameter of 0.6 mm and ground at a ball mill speed of 300 rpm for 80 minutes. The grinding beads were filtered to obtain a suspension of piperine starch nanoparticles.

[0068] During the grinding process, a break was taken after every 5 minutes to prevent the sample from overheating.

[0069] The same method as in Example 1 was used to measure the average particle size, PDI and Zeta potential of the obtained piperine starch nanoparticles at 0 day and after 7 days of storage.

[0070] The average particle size of the piperine starch nanoparticles prepared in this example is 178 ± 4 nm, the PDI is 0.301 ± 0.01, and the Zeta potential is -19.4 ± 0.3 kV. After 7 days of storage, the average particle size is 198 ± 7 nm, the PDI is 0.389 ± 0.04, and the Zeta potential is -15.9 ± 0.5 kV. It can be seen that the average particle size of the piperine starch nanoparticles prepared in this example is about 180 nm, the PDI is small, the nanoparticle size distribution is uniform, the solution has good homogeneity, the Zeta potential is moderate, and the particle surface is negatively charged, which meets the requirements of nanoparticles. After 7 days of storage, the average particle size is still less than 200 nm, the PDI does not change much, and the obtained piperine starch nanoparticles show good stability.

[0071] Example 4 Preparation of Piperine Starch Nanoparticles

[0072] In this embodiment, the preparation method of piperine starch nanoparticles is as follows:

[0073] S1. Under dark conditions, 1g of piperine and 1g of octenyl succinate starch were added to 200mL of primary water and stirred at 300rpm for 20 minutes to obtain a pre-suspension;

[0074] S2. The pre-suspension was poured into a grinding jar containing 550 g of zirconia grinding beads with a diameter of 0.6 mm and ground at a ball mill speed of 300 rpm for 100 minutes. The grinding beads were filtered to obtain a suspension of piperine starch nanoparticles.

[0075] During the grinding process, a break was taken after every 5 minutes to prevent the sample from overheating.

[0076] The same method as in Example 1 was used to measure the average particle size, PDI and Zeta potential of the obtained piperine starch nanoparticles at 0 day and after 7 days of storage.

[0077] The average particle size of the piperine starch nanoparticles prepared in this example is 156±4nm, the PDI is 0.331±0.04, and the Zeta potential is -18.7±0.3kv. After being placed for 7 days, the average particle size is 177±2nm, the PDI is 0.363±0.04, and the Zeta potential is -17.8±0.3kv. It can be seen that the average particle size of the piperine starch nanoparticles prepared in this example is about 150nm, the PDI is small, the nanoparticle size distribution is uniform, the solution has good homogeneity, the Zeta potential is moderate, and the particle surface is negatively charged, which meets the requirements of nanoparticles. After being stored for 7 days, the average particle size is still less than 200nm, and the PDI and Zeta potential do not change much. The obtained piperine starch nanoparticles show good stability.

[0078] Example 5 Preparation of Piperine Starch Nanoparticles

[0079] In this embodiment, the preparation method of piperine starch nanoparticles is as follows:

[0080] S1. Under dark conditions, 1g of piperine and 1g of octenyl succinate starch were added to 200mL of primary water and stirred at 300rpm for 20 minutes to obtain a pre-suspension;

[0081] S2. The pre-suspension was poured into a grinding jar containing 550 g of zirconia grinding beads with a diameter of 0.6 mm and ground at a ball mill speed of 300 rpm for 120 minutes. The grinding beads were filtered to obtain a suspension of piperine starch nanoparticles.

[0082] During the grinding process, a break was taken after every 5 minutes to prevent the sample from overheating.

[0083] The same method as in Example 1 was used to measure the average particle size, PDI and Zeta potential of the obtained piperine starch nanoparticles at 0 day and after 7 days of storage.

[0084] The average particle size of the piperine starch nanoparticles prepared in this embodiment is 149 ± 3 nm, PDI is 0.378 ± 0.04, and Zeta potential is 16.7 ± 0.3 kv; after being placed for 7 days, the average particle size is 161 ± 5 nm, PDI is 0.396 ± 0.08, and Zeta potential is 17.9 ± 0.8 kv, and the system shows good stability. It can be seen that the average particle size of the piperine starch nanoparticles prepared in this embodiment is less than 150 nm, the PDI is small, the nanoparticle size distribution is uniform, the solution homogeneity is good, the Zeta potential is moderate, the particle surface is negatively charged, and the demand for nanoparticles is met; the average particle size after being stored for 7 days is still less than 200 nm, the PDI is less than 0.4, and the Zeta potential does not change much, and the obtained piperine starch nanoparticles show good stability.

[0085] Example 6 Preparation of Piperine Starch Nanoparticles

[0086] In this embodiment, the preparation method of piperine starch nanoparticles is as follows:

[0087] S1. Under dark conditions, 1 g of piperine and 4 g of octenyl succinate starch were added to 200 mL of primary water and stirred at 300 rpm for 20 minutes to obtain a pre-suspension;

[0088] S2. The pre-suspension was poured into a grinding jar containing 550 g of zirconia grinding beads with a diameter of 0.6 mm and ground at a ball mill speed of 300 rpm for 120 minutes. The grinding beads were filtered to obtain a suspension of piperine starch nanoparticles.

[0089] During the grinding process, a break was taken after every 5 minutes to prevent the sample from overheating.

[0090] The same method as in Example 1 was used to measure the average particle size, PDI and Zeta potential of the obtained piperine starch nanoparticles at 0 day and after 7 days of storage.

[0091] The average particle size of the piperine starch nanoparticles prepared in this embodiment is 60 ± 1 nm, PDI is 0.325 ± 0.1, and Zeta potential is -15.9 ± 1.1 kv; after being placed for 7 days, the average particle size is 80 ± 1 nm, PDI is 0.396 ± 0.07, and Zeta potential is -16.1 ± 0.8 kv, and the system shows good stability. It can be seen that the average particle size of the piperine starch nanoparticles prepared in this embodiment is about 60 nm, the PDI is small, the nanoparticle size distribution is uniform, the solution has good uniformity, the Zeta potential is moderate, and the particle surface is negatively charged, which meets the needs of nanoparticles; the average particle size after being stored for 7 days is still less than 100 nm, the PDI is less than 0.4, and the Zeta potential does not change much, and the obtained piperine starch nanoparticles show good stability.

[0092] Example 7 Preparation of Piperine Starch Nanoparticles

[0093] In this embodiment, the preparation method of piperine starch nanoparticles is as follows:

[0094] S1. Under dark conditions, 1 g of piperine and 4 g of octenyl succinate starch were added to 200 mL of primary water and stirred at 300 rpm for 20 minutes to obtain a pre-suspension;

[0095] S2. The pre-suspension was poured into a grinding jar containing 550 g of zirconia grinding beads with a diameter of 0.6 mm and ground at a ball mill speed of 400 rpm for 120 minutes. The grinding beads were filtered to obtain a suspension of piperine starch nanoparticles.

[0096] During the grinding process, a break was taken after every 5 minutes to prevent the sample from overheating.

[0097] The same method as in Example 1 was used to measure the average particle size, PDI and Zeta potential of the obtained piperine starch nanoparticles at 0 day and after 7 days of storage.

[0098] The average particle size of the piperine starch nanoparticles prepared in this embodiment is 107 ± 1 nm, the PDI is 0.377 ± 0.02, and the Zeta potential is -17.1 ± 1.2 kv; after being placed for 7 days, the average particle size is 145 ± 2 nm, the PDI is 0.339 ± 0.01, and the Zeta potential is -15.9 ± 1 kv, and the system shows good stability. It can be seen that the average particle size of the piperine starch nanoparticles prepared in this embodiment is about 100 nm, the PDI is small, the nanoparticle size distribution is uniform, the solution has good uniformity, the Zeta potential is moderate, and the particle surface is negatively charged, which meets the needs of nanoparticles; the average particle size after being stored for 7 days is still less than 150 nm, the PDI is less than 0.4, and the Zeta potential does not change much. The obtained piperine starch nanoparticles show good stability.

[0099] Example 8 Preparation of Piperine Starch Nanoparticles

[0100] In this embodiment, the preparation method of piperine starch nanoparticles is as follows:

[0101] S1. Under dark conditions, 1 g of piperine and 4 g of octenyl succinate starch were added to 200 mL of primary water and stirred at 300 rpm for 20 minutes to obtain a pre-suspension;

[0102] S2. The pre-suspension was poured into a grinding jar containing 550 g of zirconia grinding beads with a diameter of 0.6 mm and ground at a ball mill speed of 500 rpm for 120 minutes. The grinding beads were filtered to obtain a suspension of piperine starch nanoparticles.

[0103] During the grinding process, a break was taken after every 5 minutes to prevent the sample from overheating.

[0104] The same method as in Example 1 was used to measure the average particle size, PDI and Zeta potential of the obtained piperine starch nanoparticles at 0 day and after 7 days of storage.

[0105] The average particle size of the piperine starch nanoparticles prepared in this embodiment is 135 ± 1 nm, PDI is 0.357 ± 0.1, and Zeta potential is -19.4 ± 0.5 kv; after being placed for 7 days, the average particle size is 181 ± 2 nm, PDI is 0.326 ± 0.21, and Zeta potential is -15.6 ± 1.1 kv, and the system shows good stability. It can be seen that the average particle size of the piperine starch nanoparticles prepared in this embodiment is about 130 nm, the PDI is small, the nanoparticle size distribution is uniform, the solution homogeneity is good, the Zeta potential is moderate, the particle surface is negatively charged, and the demand for nanoparticles is met; the average particle size after being stored for 7 days is still less than 200 nm, the PDI is less than 0.4, the absolute value of the Zeta potential increases, and the obtained piperine starch nanoparticles show good stability.

[0106] Example 9 Preparation of Piperine Starch Nanoparticles

[0107] In this embodiment, the preparation method of piperine starch nanoparticles is as follows:

[0108] S1. Under dark conditions, 1 g of piperine and 4 g of octenyl succinate starch were added to 200 mL of primary water and stirred at 300 rpm for 20 minutes to obtain a pre-suspension;

[0109] S2. The pre-suspension was poured into a grinding jar containing 550 g of zirconia grinding beads with a diameter of 1 mm and ground at a ball mill speed of 300 rpm for 120 minutes. The grinding beads were filtered to obtain a suspension of piperine starch nanoparticles.

[0110] During the grinding process, a break was taken after every 5 minutes to prevent the sample from overheating.

[0111] The same method as in Example 1 was used to measure the average particle size, PDI and Zeta potential of the obtained piperine starch nanoparticles at 0 day and after 7 days of storage.

[0112] The average particle size of the piperine starch nanoparticles prepared in this embodiment is 184 ± 1 nm, PDI is 0.161 ± 0.03, and Zeta potential is -16.7 ± 0.8 kv; after being placed for 7 days, the average particle size is 271 ± 4 nm, PDI is 0.387 ± 0.2, and Zeta potential is -14.8 ± 0.4 kv, and the system shows good stability. It can be seen that the average particle size of the piperine starch nanoparticles prepared in this embodiment is about 180 nm, PDI is less than 0.2, the nanoparticle size distribution is uniform, the solution homogeneity is good, the Zeta potential is moderate, the particle surface is negatively charged, and the demand for nanoparticles is met; the average particle size after being stored for 7 days is still about 270 nm, PDI is less than 0.4, and the Zeta potential does not change much, and the obtained piperine starch nanoparticles show good stability.

[0113] Comparative Example 1

[0114] The preparation method of piperine nanoparticles is the same as that of Example 1, except that octenyl succinate-esterified starch is replaced by hydroxypropyl methylcellulose.

[0115] The same method as in Example 1 was used to measure the average particle size, PDI and Zeta potential of the obtained piperine nanoparticles at 0 day and after 7 days of storage.

[0116] The piperine nanoparticles prepared in this comparative example had an average particle size of 277±2 nm, a PDI of 0.2±0.01, and a Zeta potential of -17.2±1.5 kV. After 7 days of storage, the average particle size was 321±5 nm, the PDI was 0.354±0.05, and the Zeta potential was -15.7±0.6 kV. It can be seen that although the prepared piperine nanoparticles had a small PDI, their average particle size was larger and the absolute value of the potential was lower. After 7 days of storage, their PDI was less than 0.4, and the Zeta potential did not change much. However, the average particle size of the nanoparticles was greater than 300 nm, which was relatively large and could not meet the requirement of a smaller average particle size for nanoparticles.

[0117] Comparative Example 2

[0118] The preparation method of piperine nanoparticles is the same as that of Example 1, except that octenyl succinate-esterified starch is replaced by polyvinyl pyrrolidone.

[0119] The same method as in Example 1 was used to measure the average particle size, PDI and Zeta potential of the obtained piperine nanoparticles at 0 day and after 7 days of storage.

[0120] The piperine nanoparticles prepared in this comparative example had an average particle size of 768±14 nm, a PDI of 0.277±0.02, and a Zeta potential of -5±0.19 kV. After 7 days of storage, the average particle size was 954±20 nm, the PDI was 0.388±0.16, and the Zeta potential was -5±0.11 kV. It can be seen that although the prepared piperine nanoparticles had a small PDI and a relatively uniform particle distribution, the nanoparticles had a large average particle size and a very low absolute Zeta potential. After 7 days of storage, the average particle size was greater than 900 nm, and the particle size variation range was greater than 100 nm. The large particle size variation resulted in poor system stability, which did not meet the requirement for high stability of nanoparticles.

[0121] Comparative Example 3

[0122] The preparation method of piperine starch nanoparticles is the same as that of Example 1, except that the grinding time is 20 minutes.

[0123] The same method as in Example 1 was used to measure the average particle size, PDI and Zeta potential of the obtained piperine starch nanoparticles at 0 day and after 7 days of storage.

[0124] The average particle size of the piperine starch nanoparticles prepared in this comparative example was 417±6nm, PDI was 0.236±0.02, and Zeta potential was -22.6±1.5kv. After 7 days of storage, the average particle size was 518±5nm, PDI was 0.298±0.15, and Zeta potential was -20.8±1.1kv. It can be seen that although the piperine starch nanoparticle suspension prepared in this comparative example has a small PDI, its average particle size is larger. After 7 days of storage, the average particle size of the nanoparticles is greater than 500nm, and the particle size variation range is greater than 100nm. The average particle size variation is large, and the system stability is poor, which cannot meet the requirement of high stability of nanoparticles.

[0125] Comparative Example 4

[0126] The preparation method of piperine starch nanoparticles is the same as that of Example 6, except that the mass ratio of piperine to octenyl succinate starch is 4:1, that is, 4 g of piperine to 1 g of octenyl succinate starch.

[0127] The same method as in Example 1 was used to measure the average particle size, PDI and Zeta potential of the obtained piperine starch nanoparticles at 0 day and after 7 days of storage.

[0128] The average particle size of the piperine starch nanoparticles prepared in this comparative example was 335±6nm, PDI was 0.408±0.03, and Zeta potential was -9±3kV. After 7 days of storage, the average particle size was 511±6nm, PDI was 0.388±0.14, and Zeta potential was -7.7±2kV. It can be seen that the average particle size and PDI of the obtained piperine starch nanoparticles were larger, the particle size distribution was uneven, the absolute value of Zeta potential was low, and the particles were prone to aggregation. After 7 days of storage, the average particle size of the nanoparticles was greater than 500nm, the particle size variation range was greater than 100nm, the average particle size variation was large, the system stability was poor, and the requirement for high stability of the nanoparticles was not met.

[0129] Comparative Example 5

[0130] The preparation method of piperine starch nanoparticles was the same as that of Example 6, except that the diameter of the zirconium oxide grinding beads was 0.1 mm.

[0131] The same method as in Example 1 was used to measure the average particle size, PDI and Zeta potential of the obtained piperine starch nanoparticles at 0 day and after 7 days of storage.

[0132] The average particle size of the piperine starch nanoparticles prepared in this comparative example was 62±6nm, PDI was 0.448±0.04, and Zeta potential was -15.7±0.9kv. After 7 days of storage, the average particle size was 342±10nm, PDI was 0.341±0.12, and Zeta potential was -14.3±0.8kv. It can be seen that although the average particle size and Zeta potential of the prepared piperine starch nanoparticles are similar, the PDI is larger, the particle size distribution of the nanoparticles is uneven, and the nanoparticles are prone to aggregation. The average particle size of the particles after 7 days of storage is greater than 300nm, the average particle size changes greatly, and the system stability is poor, which cannot meet the demand for high stability of the nanoparticles.

[0133] Example 10 Effects of Different Drying Processes on Piperine Starch Nanoparticles

[0134] The present invention uses the piperine starch nanoparticle suspension obtained in Example 6 as a sample, and uses spray drying and freeze drying to dry the obtained piperine starch nanoparticles, respectively, to explore the effects of different drying methods on their average particle size, etc.

[0135] The drying conditions are as follows:

[0136] Spray drying: fan frequency 50 Hz, air inlet temperature 120°C, pump speed 10%; after drying, the spray-dried sample was sealed and stored in a 4°C refrigerator away from light.

[0137] Freeze drying: The piperine starch nanoparticle suspension was stored at -20°C and transferred to a freeze dryer after complete freezing. Freeze drying was performed under a vacuum condition of 0.37 mbar and -70°C for 48 hours. After drying, the freeze-dried sample was sealed and stored in a 4°C refrigerator away from light.

[0138] The dried samples were tested for redispersibility and storage stability.

[0139] 1. Redispersibility (the ability of drug nanoparticles to reconstitute after contact with water, i.e., redispersibility)

[0140] 0.5 g of piperine starch nanoparticle powder was dispersed in 20 mL of first-grade water, diluted to an appropriate multiple, and the average particle size distribution of the particles was measured using a Zatasizer Nano ZS 90 dynamic light scattering nanoparticle size analyzer.

[0141] The redispersibility index (RDI) is a quantitative measure of the redispersibility of a sample and is calculated according to the following formula:

[0142] RDI (%) = (D0 / D) × 100%

[0143] D0 represents the average particle size of the original piperine starch nanoparticles

[0144] D represents the average particle size of piperine starch nanoparticles after drying and re-dissolution

[0145] The closer the RDI value is to 100%, the more the nanosuspension can be almost completely redispersed to its original average particle size after rehydration.

[0146] Table 1 Redispersibility index of piperine starch nanoparticles after spray drying and freeze drying

[0147]

[0148] 2. Storage stability

[0149] The freshly prepared piperine starch nanoparticle powder was sealed and stored in the dark. After 0, 7, and 30 days, the solution was redissolved and the appearance was observed. The average particle size, PDI, and Zeta potential of the particles were measured using a Zatasizer Nano ZS 90 dynamic light scattering nanoparticle size analyzer.

[0150] Table 2 Average particle size, PDI and Zeta potential of spray-dried and freeze-dried piperine starch nanoparticles

[0151]

[0152] It can be seen from Tables 1 and 2 that spray drying or freeze drying has a certain improvement on the short-term (7 days) redispersibility and storage stability of piperine starch nanoparticles. However, the average particle size of the spray-dried piperine starch nanoparticles after reconstitution is lower than that of the freeze-dried piperine starch nanoparticles, and its redispersibility and absolute value of potential value are higher. Moreover, after storage, the average particle size after reconstitution can still be less than 150 nm, indicating that the spray-dried piperine starch nanoparticles have better redispersibility and storage stability than the freeze-dried piperine starch nanoparticles, the particles are evenly distributed and the system is more stable, which can meet the characteristics of the prepared nanoparticles with a small average particle size, uniform particle size distribution and high system stability.

[0153] Example 11

[0154] The present invention also performs Fourier transform infrared spectroscopy, differential scanning calorimetry, and X-ray powder diffraction analysis on spray-dried piperine starch nanoparticles, freeze-dried piperine starch nanoparticles, a spray-dried piperine starch mixture, a piperine starch mixture (only 1 g of piperine and 4 g of octenylsuccinate starch are uniformly mixed in water), spray-dried pure piperine nanoparticles, and pure piperine, and determines the release rate of piperine in gastrointestinal fluid in different samples through in vitro simulated digestion.

[0155] Spray drying the piperine starch mixture refers to spray drying the mixture under the conditions of a fan frequency of 50 Hz, an inlet air temperature of 120° C., and a pump speed of 10%.

[0156] The piperine starch mixture is prepared by adding 1 g of piperine and 4 g of octenyl succinate starch to 200 mL of first-grade water under light-proof conditions, and stirring the mixture at 300 rpm for 20 minutes.

[0157] The method comprises the following steps of: adding 1 g of piperine to 200 mL of first-grade water under light-proof conditions, stirring the mixture at 300 rpm for 20 minutes to obtain a presuspension; pouring the presuspension into a grinding jar containing 550 g of zirconium oxide grinding beads with a diameter of 0.6 mm, grinding the mixture at a ball mill speed of 300 rpm for 120 minutes, filtering the zirconium oxide grinding beads, and obtaining a piperine suspension; and pausing the grinding for a period of time after every 5 minutes to prevent the sample from overheating. Finally, spray drying the obtained piperine suspension under conditions of a fan frequency of 50 Hz, an inlet air temperature of 120° C., and a pump speed of 10%.

[0158] 1. Fourier transform infrared spectroscopy (ATR-FTIR)

[0159] Place the ATR accessory in the optical path of the infrared spectrometer, scan the air background, and then take an appropriate amount of sample powder and place the surface to be tested close to the infrared transparent crystal surface of the ATR accessory. Scan with the Fourier transform infrared spectrometer, and set the scanning range to 400-4000cm -1 , the resolution is set to 4cm -1 , the number of scans is set to 64, and the infrared spectra of the samples are obtained. The infrared spectra of different samples are shown in Figure 1 As shown by Figure 1 The wavenumbers of piperine starch nanoparticles experienced a slight shift but remained within the wavenumber range of the functional groups. FTIR characterization results showed that no new functional groups were formed between piperine and octenylsuccinate starch, indicating that no chemical interaction occurred between piperine and octenylsuccinate starch during the wet ball milling and drying processes, and that piperine retained its original properties.

[0160] 2. Differential Scanning Calorimetry (DSC) Analysis

[0161] The sample powders were analyzed using a differential scanning calorimeter. The instrument was calibrated before the measurement. 5.0 mg of powder was then placed in a sealed aluminum pan and heated from 25°C to 200°C at a heating rate of 5°C / min. The melting point was measured under a nitrogen purge of 30 mL / min. An empty pan was used as a control. The differential scanning calorimetry analysis results of different samples are shown in Figure 2. Figure 2 The initial melting point (°C), peak melting point (°C) and melting enthalpy (ΔHm (J / g)) of different samples are shown in Table 3. Figure 2 As shown in Table 3, the peak melting points of spray-dried piperine starch nanoparticles, freeze-dried piperine starch nanoparticles, spray-dried piperine starch mixture, piperine starch mixture, spray-dried piperine nanoparticles, and pure piperine were 129.6°C, 129.37°C, 131.15°C, 130.94°C, 129.49°C, and 131.31°C, respectively. Although these melting points are lower than those of pure piperine, they remain within a reasonable range. Lower melting points indicate weaker lattice energy; lower lattice energy increases crystal solubility and dissolution rate.

[0162] Furthermore, the heat of fusion of the spray-dried piperine-starch mixture was observed to be higher than that of the mixed mixture, indicating that spray drying is not the primary factor in reducing the drug's lattice energy. The heat of fusion of pure piperine decreased from 100.4 J / g to 83.1 J / g after wet ball milling and spray drying, indicating that wet ball milling is the primary factor in reducing the lattice energy of piperine nanoparticles. The decrease in the melting point and heat of fusion of the piperine nanoparticles is primarily due to wet ball milling reducing the average particle size of piperine, resulting in a decrease in crystallinity and melting point, rather than a crystalline transformation of piperine. This also demonstrates that piperine retains its original pharmacological activity after high-energy ball milling and drying of the mixture of piperine and octenylsuccinate starch.

[0163] Table 3 Onset melting point, peak melting point and melting enthalpy of different samples

[0164]

[0165] 3. X-ray powder diffraction (XRD)

[0166] Take an appropriate amount of sample powder for X-ray diffraction analysis. Measurement conditions: Cu target, high voltage 40kV, single current 40mA, scanning 2θ angle 5°~60°, scanning speed 5° / min; record the X-ray diffraction curve of the sample. The X-ray diffraction curves of different samples are as follows: Figure 3 As shown. Figure 3 It can be seen that the spray-dried piperine starch nanoparticles, freeze-dried piperine starch nanoparticles, spray-dried piperine starch mixture, piperine starch mixture, spray-dried piperine nanoparticles, and pure piperine all exhibit distinct sharp peaks, indicating a crystalline state. Characteristic peaks of pure piperine are observed at 14.34, 19.83, 25.92, and 27.71°. The diffraction patterns of the spray-dried piperine starch nanoparticles and freeze-dried piperine starch nanoparticles are identical to those of the piperine starch mixture and the spray-dried piperine starch mixture, indicating the same crystallization mechanism, but with decreased peak intensities. The decreased X-ray diffraction peak intensity indicates a decrease in the crystallinity of the samples, which may be due to the change in the average particle size of the piperine starch nanoparticles from micrometers to nanometers. This suggests that the high energy input during wet ball milling and the drying process after mixing piperine with octenylsuccinate-containing starch do not alter the crystalline state of piperine.

[0167] From the above results, it can be seen that the XRD results are consistent with the results of FTIR and DSC, and piperine still maintains its original pharmacological activity.

[0168] 4. Cumulative release of piperine in simulated gastrointestinal fluid

[0169] The simulated gastric fluid used for in vitro simulated digestion consisted of 34.2 mM sodium chloride, 2 mg / mL pepsin, and had a pH of 1.6. The simulated intestinal fluid used for in vitro simulated digestion consisted of 4.64 mM maleic acid, 34.2 mM sodium chloride, 1.95 mM sodium deoxycholate, and 10 mg / mL pancreatin, and had a pH of 7.5.

[0170] Simulated gastric digestion: Accurately weigh 30 mg of sample powder and use the same amount of pure piperine as a control. Add 50 mL of gastric digestion fluid and adjust the pH of the mixed solution to 1.6. Then digest under magnetic stirring at 100 rpm and 37°C.

[0171] Simulated intestinal digestion: The pH of the gastric digestive fluid after 1 h of digestion was adjusted to 7.5 with 1 mol / L NaOH to inactivate pepsin and stop gastric digestion; 30 mL of simulated intestinal fluid was added, and then digestion was carried out under magnetic stirring at 100 rpm and 37°C.

[0172] The different samples described in this example, namely, spray-dried piperine starch nanoparticles, freeze-dried piperine starch nanoparticles, spray-dried piperine starch mixture, spray-dried piperine pure nanoparticles, and pure piperine, were digested in the above-mentioned simulated gastric fluid for 60 min and then digested in simulated intestinal fluid for 120 min. 1 mL of the digestion fluid was collected every 30 min and centrifuged at 12,500 rpm and 4° C. for 30 minutes. The supernatant was aspirated using a syringe and filtered through a 0.22 μm membrane filter to separate a clear and transparent supernatant, and the volume was recorded as V. 9 V of methanol was added, and the absorbance of piperine was measured using an ultraviolet spectrophotometer at a wavelength of 342 nm. The concentration of piperine was calculated based on the prepared piperine standard curve to measure the release of piperine during the simulated gastrointestinal fluid digestion, and a cumulative release curve was plotted.

[0173] Preparation of standard curve:

[0174] (1) Accurately weigh 40 mg of piperine standard sample dried to constant weight at 120°C and place it in a 100 mL beaker. Dissolve it in methanol and dilute to volume in a 100 mL volumetric flask, then shake well to obtain a 0.4 mg / mL piperine standard solution.

[0175] (2) Measurement of standard products and drawing of standard curves

[0176] Accurately pipette 62.5, 125, 187.5, 250, 312.5, and 375 μL of piperine standard solution into 5 mL volumetric flasks and dilute to the mark to obtain 5 μg / mL, 10 μg / mL, 15 μg / mL, 20 μg / mL, 25 μg / mL, and 30 μg / mL standard solutions. The absorbance was measured at 342 mm using a UV spectrophotometer (Tai. Cai & Dai, 2011). Using a blank as a reference, absorbance was plotted against drug concentration to obtain a regression curve equation. Linear fitting was performed using the least squares method to obtain the linear regression equation for c and A, as well as the correlation coefficient, R.

[0177] The test data of piperine standard curve are shown in Table 4; the piperine standard curve obtained by drawing is shown in Table 4. Figure 4 shown.

[0178] Table 4 Test data of piperine standard curve

[0179]

[0180] Cumulative release of piperine (%) = CV / m × dilution factor × 100%

[0181] Where C is the concentration of piperine in the supernatant; V is the volume of the supernatant; and m is the content of piperine in the sample.

[0182] The results of the cumulative release of piperine from spray-dried piperine starch nanoparticles, freeze-dried piperine starch nanoparticles, spray-dried piperine starch mixture, spray-dried piperine pure nanoparticles and piperine pure are as follows: Figure 5 As shown by Figure 5It can be seen that the release amount of pure piperine in simulated gastrointestinal fluid is low, and the final cumulative release amount in simulated gastrointestinal digestion is only 29.27%. This is attributed to the low solubility and low stability of pure piperine. During the digestion process, some of it precipitated at the bottom, limiting the transfer of piperine to the micellar layer. The cumulative release amount of the spray-dried-piperine starch mixture in the intestine is only 29.37%, indicating that under spray-drying conditions, the addition of octenyl succinate starch stabilizer has no significant effect on the cumulative release amount of pure piperine in the simulated gastrointestinal tract. The cumulative release amount of spray-dried-pure piperine nanoparticles in the simulated gastrointestinal tract is 32.78%, indicating that reducing the average particle size of pure piperine by ball milling can increase the dissolution rate of piperine to a certain extent, thereby improving the cumulative release rate of piperine in the simulated gastrointestinal tract. The final cumulative release of spray-dried piperine starch nanoparticles and freeze-dried piperine starch nanoparticles in the intestine was 51.39% and 40.71%, which was significantly higher than the cumulative release rate of pure piperine. This shows that after wet ball milling, the average particle size of piperine increased from micrometer level to nanometer level, the crystallinity decreased, and the dissolution rate increased. By adding octenyl succinate starch stabilizer, piperine formed a stable suspension in the aqueous solution, reducing the aggregation and agglomeration of piperine nanoparticles, thereby greatly improving the solubility and dissolution rate of piperine, and increasing the cumulative release of piperine in the gastrointestinal fluid of different samples.

[0183] In addition, the states of pure piperine, piperine and octenylsuccinate starch mixture (1:4), spray-dried piperine starch nanoparticle suspension, and freeze-dried piperine starch nanoparticle suspension after sealed storage for 0, 7, and 30 days are shown in Figure 2. Figure 6 As shown by Figure 6 As can be seen, pure piperine and the piperine starch mixture showed particle aggregation and agglomeration on day 0, with slight precipitation in the solution. After 7 days, distinct stratification and precipitation appeared. After 30 days, the particles of pure piperine and the piperine starch mixture showed significant coagulation and flocculation, settling under gravity to form a precipitate. However, the spray-dried piperine starch nanoparticle suspension and freeze-dried piperine starch nanoparticle suspension showed no significant change in appearance during storage, maintaining their suspension state well. The particles aggregated and flocculated slowly, demonstrating high stability.

[0184] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be considered as equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. A piperine starch nanoparticle, characterized in that The nanoparticles are prepared from piperine and a stabilizer in a mass ratio of 1:1 to 4; the stabilizer is octenyl succinate-esterified starch; and the preparation method of the piperine starch nanoparticles comprises the following steps: S1. Under dark conditions, the formulated amount of piperine and stabilizer was added to primary water and stirred to obtain a pre-suspension; S2. The pre-suspension obtained in step S1 was ground with zirconium oxide grinding beads for a total grinding time of 40 to 120 minutes, and the grinding beads were filtered to obtain a suspension of piperine starch nanoparticles; the amount of the zirconium oxide grinding beads was as follows: 520 to 580 g of zirconium oxide grinding beads were added for every 2 to 8 g of piperine and stabilizer; the diameter of the zirconium oxide grinding beads was 0.6 to 1 mm; S3. spraying or freeze-drying the piperine starch nanoparticle suspension obtained in step S2 to obtain solidified piperine starch nanoparticle powder, namely the piperine starch nanoparticles.

2. The nanoparticles according to claim 1, characterized in that In S1, the amount of first-grade water is as follows: 200 mL of first-grade water is added for every 2 to 8 g of piperine and stabilizer.

3. The nanoparticles according to claim 1, characterized in that In S1, the stirring speed is 250 to 350 rpm, and the stirring time is 18 to 22 minutes.

4. The nanoparticles according to claim 1, characterized in that In S3, the sample is spray dried.

5. The nanoparticles according to claim 4, characterized in that The spray drying conditions are: fan frequency 40-60 Hz, air inlet temperature 118-122° C., and pump speed 8-12%.

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