Polypeptide eye absorption enhancer and use thereof

Abstract

The present disclosure belongs to the field of pharmaceutical preparations and relates to the design of a series of lipophilic derivatives by using wild-type penetrating peptide penetratin. These penetratin derivatives have a strong ability to penetrate the ocular tissues and do not cause ocular tissue toxicity. As ocular absorption enhancers, non-invasive routes could be used to achieve intraocular drug delivery and increase the ocular bioavailability of drugs. These penetratin derivatives and the ophthalmic drug delivery system constructed by them are used for eye drop administration, which could replace the intraocular injection with poor patients compliance, which greatly enhances the convenience and safety of the treatment of intraocular and fundus diseases.

Claims

1. A penetratin derivative comprising the amino acid sequence of: TABLE-US-00003 RX.sub.1IKIWFX.sub.2X.sub.3RRMKWKK (SEQ ID NO: 2) wherein X.sub.1, X.sub.2, and X.sub.3 are hydrophobic amino acids selected from the group consisting of A, V, L, I, P, F, W, M, α-aminobutyric acid, α-aminopentanoic acid, α-aminohexanoic acid, α-aminoheptanoic acid, and combinations thereof.

2. A penetratin derivative of claim 1 comprising the amino acid sequence of TABLE-US-00004 RWIKIWFWWRRMKWKK (SEQ ID NO. 57).

3. A penetratin derivative selected from the group consisting of SEQ ID NO: 45, SEQ ID NO: 49, SEQ ID NO: 51, SEQ ID NO: 53, and SEQ ID NO: 55.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1: Qualitative evaluation of cellular uptake of complexes of penetratin derivatives covalently linked with small molecules

(2) Wherein human corneal epithelial cells and human conjunctival epithelial cells were incubated with penetratin derivative-FAM covalent complex (100 nM) for 0.5 h, 1 h, 2 h, and 4 h, respectively, and scale bar represents 100 μm.

(3) FIG. 2: Qualitative evaluation of cellular uptake of complexes of penetratin derivatives covalently linked with small molecules

(4) Wherein human corneal epithelial cells and human conjunctival epithelial cells were incubated with penetratin derivative-FAM covalent complexes for 4 h, and Fm was the average fluorescence intensity of the cells.

(5) FIG. 3: Evaluation of the cytotoxicity of penetratin derivatives

(6) Wherein human corneal epithelial cells and human conjunctival epithelial cells were incubated with penetratin derivatives for 12 h, and the cell survival rate of the experimental group relative to the negative control group was measured by MTT method.

(7) FIG. 4: Evaluation of the penetrating ability of isolated ocular tissues of complexes of penetratin derivatives covalently linked with small molecules

(8) Wherein in FIG. 4A, a is a penetration curve of penetratin derivative-FAM covalent complex on isolated cornea of rabbit eyes, b is a penetration curve of penetratin derivative-FAM covalent complex on isolated sclera of rabbit eyes, c is the apparent permeability coefficient; FIG. 4B is a fluorescent section of DAPI staining of the isolated tissues of the blank group and the experimental group, and scale bar represents 100 μm.

(9) FIG. 5: Evaluation of in vitro tissue toxicity of complexes of penetratin derivatives covalently linked with small molecules

(10) Wherein FIG. 5A is the corneal hydration value of the blank group and the penetratin derivative-FAM covalent complex group; FIG. 5B is the scleral hydration value of the blank group and the penetratin derivative-FAM covalent complex group; and FIG. 5C is HE stained sections of isolated tissues from the blank group and penetratin derivative-FAM covalent complex group, and scale bar represents 100 μm.

(11) FIG. 6: Distribution of complexes of penetratin derivatives covalently linked with small molecules in the eyes of living mice

(12) Wherein FIG. 6A shows the distribution of penetratin derivative-FAM covalent complexes in the anterior (corneal) and posterior (retinal) segments of mice at different time points (10 min, 0.5 h, 1 h, 2 h, 4 h, 6 h) after administration of the conjunctival sac; FIG. 6B shows the distribution of the penetratin derivative-FAM covalent complex in the anterior segment (cornea) and posterior segment (retina) of the mouse 10 min after administration of the conjunctival sac; FIG. 6C is the result of semi-quantitative analysis of intraocular distribution of penetratin derivative-FAM covalent complex 10 min, 1 h, and 6 h after administration.

(13) FIG. 7 Ocular absorption of a non-covalent complex of a Penetratin derivative and an antisense oligonucleotide drug

(14) Wherein FIG. 7A shows the distribution of each group of non-covalent complexes (ASO/PG5, ASO/PG5/HA, ASO/PG5/HA/Pene) in mice at different time points (1 h, 2 h, 6 h, and 8 h) after administration of the conjunctival sac; FIG. 7B shows the distribution of each group of green fluorescent labeled ASO in each area of the retina.

(15) FIG. 8 Evaluation of cell uptake of non-covalent complexes of fluorouracil modified with Penetratin derivatives and antisense oligonucleotide dual loading drugs

(16) Wherein mouse fibroblasts were incubated with different prescription dual loading drugs non-covalent complexes (dual/PG5, dual/PG5/HA, dual/PG5/HA/Pene) for 4 h, and then the average fluorescence intensity of cells in each group was measured.

DETAILED DESCRIPTION OF THE INVENTION

(17) The present invention is further illustrated below with reference to specific embodiments of the present invention, but the scope of protection is not limited.

Example 1

(18) Preparation of covalently linked complexes of Penetratin derivatives and small molecular substances: based on the structure of wild-type penetratin, the sequences of the original basic amino acid and hydrophobic amino acid were kept unchanged, then peptide solid-phase synthesis technology was used to replace hydrophilic amino acids glutamine (Q) and asparagine (N) in penetratin molecules with hydrophobic tryptophan (W), respectively, thereby a series of polypeptide derivatives were obtained. One additional lysine (K) was attached to the C-terminus of the tryptophan-substituted penetratin derivative, and a fluorescent probe carboxyfluorescein (FAM) was linked to the amino side chain of lysine to form a covalent complex, the amino acid sequence of the covalent complex is shown in Table 2.

(19) At the same time, the sequences of the original basic amino acid and hydrophilic amino acid the wild-type penetratin were kept unchanged, then peptide solid-phase synthesis technology was used to replace the more hydrophobic isoleucine (I), phenylalanine (F), tryptophan (W), and methionine (M) in penetratin molecules with alanine (A), so as to obtain a hydrophilic penetratin derivative 6A, it was further fluorescently labeled with FAM as a hydrophilic control polypeptide.

(20) TABLE-US-00002 TABLE 2 Amino acid sequences of covalent complexes of Penetratin derivatives and fluorescent probes Abbreviation Amino acid sequence Penetratin RQIKIWFQNRRMKWKKK-FAM (SEQ ID NO. 79) 2-W RWIKIWFQNRRMKWKKK-FAM (SEQ ID NO. 80) 8-W RQIKIWFWNRRMKWKKK-FAM (SEQ ID NO. 81) 9-W RQIKIWFQWRRMKWKKK-FAM (SEQ ID NO. 82) 28-W RWIKIWFWNRRMKWKKK-FAM (SEQ ID NO. 83) 29-W RWIKIWFQWRRMKWKKK-FAM (SEQ ID NO. 84) 89-W RQIKIWFWWRRMKWKKK-FAM (SEQ ID NO. 85) 289-W RWIKIWFWWRRMKWKKK-FAM (SEQ ID NO. 86) 6A RQAKAAAQNRRAKAKKK-FAM (SEQ ID NO. 87)

(21) Using the above method, the applicant also prepared penetratin derivatives substituted by natural amino acids and non-natural amino acids such as Alanine (A), Valine (V), Leucine (L), Isoleucine (I), Proline (P), Phenylalanine (F), Tryptophan (W), Methionine (M), α-aminobutyric acid, α-aminopentanoic acid, α-aminohexanoic acid, α-aminoheptanoic acid and their combination. The amino acid sequences are shown in Table 1.

(22) Using the above methods, the applicant also connected the drugs used to treat cataracts, bacterial endophthalmitis, fungal endophthalmitis, glaucoma, antimetabolite, uveal disease, retinal disease and optic nerve disease with the penetratin derivative through a covalent bond to form a covalent complex of the penetratin derivative and the small molecule drug.

Example 2

(23) Qualitative evaluation of cell uptake of the covalently linked complex of Penetratin derivatives and small molecular substances: well-growing human corneal epithelial cells (HCEC) and human conjunctival epithelial cells (NHC) were inoculated into 24-well plates at 5×10.sup.3 cells/cm.sup.2, respectively. In the well plate, the culture solution was changed once a day after inoculation, and the experiment was performed after 2 to 3 days of culture. After discarding the culture solution, washing it three times with sterile PBS, adding serum-free DMEM solution containing 100 nM complex of penetratin derivative and FAM, and incubating at 37° C. and 5% CO.sub.2 for a period of time (0.5 h, 1 h, 2 h and 4 h). After the treatment, the solution was discarded, and the positively charged adsorbed substance was washed away with a PBS buffer solution containing 0.02 mg/mL heparin sodium, observed under inverted fluorescence microscope after staining cell nuclei with diimidylphenylindole (DAPI).

(24) The results showed that for wild-type penetratin, the FAM fluorescence signal was still weak after 4 h incubation, and for the hydrophilic penetratin derivative 6A, the FAM fluorescence signal was weaker. Obviously, the lipophilic penetratin derivatives have strong FAM fluorescence signals, particularly the penetratin derivatives 9-W, 28-W, 89-W, and 289-W. After 1 h of administration, a clear FAM fluorescence signal was observed from the cells. And with the increase of incubation time, the fluorescence signal of FAM also increased. It is shown that using hydrophobic amino acids to replace the original hydrophilic amino acids in penetratin molecules is beneficial to promote the uptake of small molecules carried by polypeptides by cells, and increased hydrophilicity reduces cell uptake.

Example 3

(25) Quantitative evaluation of cell uptake of the covalently linked complex of Penetratin derivatives and small molecular substances: well-growing HCEC and NHC cells were inoculated into 24-well plates at 5×10.sup.3 cells/cm.sup.2, respectively. In the well plate, the culture solution was changed once a day after inoculation, and the experiment was performed after 2 to 3 days of culture. After discarding the culture solution, washing it three times with sterile PBS, adding serum-free DMEM solution containing 3 μM complexes of penetratin derivative and FAM, and incubating at 37° C. and 5% CO.sub.2 for 4 h. When finished, the solution was discarded, and the positively charged adsorbed substance was washed away with a PBS buffer solution containing 0.02 mg/mL heparin sodium, the cells were digested, resuspended in 200 μL of sterile PBS buffer solution, and flow cytometry was performed after pipetting. The cell count of each sample was 10.sup.4. Unadministered cells served as a negative control group.

(26) In HCEC cells, the cellular uptake of complex of lipophilic penetratin derivative and FAM was significantly higher than that of complex of wild-type penetratin and FAM (p<0.001), and the average fluorescence intensity is 1.7 (29-W)˜7.7 (89-W) times of the wild-type penetratin group. The average fluorescence intensity of the hydrophilic penetratin derivative 6A was only 1/10 of that of the wild-type penetratin group (p<0.001). For NHC cells, the average fluorescence intensity of hydrophobic penetratin derivatives is 2.8 (2-W) to 18.9 (29-W) times that of the wild-type penetratin (p<0.01). The average fluorescence intensity of hydrophilic penetratin derivatives is only ¼ of that of the wild-type penetratin (p<0.001). Based on the above results, the cellular uptake of lipophilic penetratin derivatives was significantly higher than that of the wild-type penetratin for both HCEC and NHC cells, while the cellular uptake that of hydrophilic penetratin derivatives was significantly lower than that of the wild-type penetratin, consistent with the results of qualitative uptake.

Example 4

(27) Evaluation of cytotoxicity of Penetratin derivatives: HCEC and NHC cells in good logarithmic growth state were plated in 60 inner wells of a 96-well plate at a concentration of 3,000 cells/well, respectively, and the edges were filled with sterile PBS buffer solution. Incubated at 37° C. and 5% CO.sub.2 until the cell monolayer were spread over the bottom of the plate. The culture solution was discarded and washed it 3 times with sterile PBS buffer, and then added 200 μL of culture solution containing penetratin derivatives with different concentrations. After incubated in the cell incubator for 12 hours, the culture solution was discarded and washed 3 times with sterile PBS buffer, and complete medium was added to continue incubating for 12 hours. 20 μL of thiazole blue (MTT) solution (5 mg/mL) was then added to each well. After incubated for 4 hours, the liquid was carefully discarded. After washed 3 times with PBS buffer, 150 μL of dimethyl sulfoxide (DMSO) was added to each well. After shaking at low speed for 20 minutes on a shaker, the absorbance of each well was measured at OD490 nm on a microplate reader. The blank zeroing wells (medium, MTT, DMSO) and negative control wells (cell, medium, MTT, DMSO) were set at the same time.

(28) The results showed that under the conditions of the concentration range to be tested (o be μM), the cell growth status did not change significantly, and penetratin and its derivatives showed no toxic effect on HCEC and NHC cells.

Example 5

(29) Evaluation of in vitro tissue permeability of the covalently linked complex of Penetratin derivatives and small molecular substances: the experimental rabbits were anesthetized with pentobarbital sodium (30 mg/kg), which is injected via ear vein, and sacrificed by injection with excessive chloral hydrate (150 mg/kg). After separation of the conjunctiva, carefully removed the entire eyeball, make a circumcision at about 2 mm from the limbus of cornea and remove the cornea, and removed the iris and other tissues to obtain an experimental cornea. The rest of the eyeballs were removed from the retina and other tissues to obtain an experimental sclera. Both the cornea and sclera were carefully washed with Ringer's solution 3 times before use. The experiment was started within 30 min after the animals were sacrificed. The freshly isolated cornea and sclera were carefully sandwiched between two diffusion cells, with the epithelial surface facing a diffusion cell (supply cell) on the left, the diffusion window diameter was 10.25 mm, and the diffusion area was 0.825 cm.sup.2. 3.5 mL of Ringer's solutions were added to the supply cell and a receiving cell on the right, respectively. Circulating water was passed therein, and the water temperature was kept at 34° C.±0.5° C. After the system was equilibrated for 10 minutes, the solution in the supply cell was removed, and a solution of the complex of Penetratin derivative and FAM was added at a concentration of 7.5 μM. The entire diffusion device was placed on the diffuser, magnetic stirring was maintained, the constant temperature water bath was maintained at 34° C.±0.5° C., and a mixed gas (O.sub.2:CO.sub.2=95:5, volume ratio) was passed into the diffusion medium. After the experiment was started, samples were taken at preset time points, 500 μL each time in the receiving cell, and 500 μL of fresh Ringer's solution was immediately added. Immediately after the experiment, the fluorescence intensity of the sample was measured. After removing the cornea and sclera, carefully rinsed the surface 3 times with Ringer's solution to remove the parts other than the diffuse surface. After the remaining tissue was fixed with Davidson's solution, frozen sections of DAPI staining were used to observe the tissue distribution of polypeptide-linked fluorescent probe.

(30) The results in FIG. 4A show that the process of the fluorescent probe connected to the polypeptide permeating the cornea and sclera in vitro is a time-dependent linear process. According to the apparent transmission coefficient (P.sub.app) values obtained from each curve, for isolated cornea, the P.sub.app values of lipophilic derivatives 2-W, 28-W, and 289-W are 1.2, 1.3, and 1.4 times that of wild-type penetratin, respectively (p<0.05), while the hydrophilic derivative 6A is only ⅕ of the wild-type penetratin (p<0.001). For isolated sclera, the P.sub.app values of derivatives 2-W, 28-W, and 289-W were 1.1, 1.5, and 2.1 times that of wild-type penetratin (p<0.001), while 6A was only ⅔ of wild-type penetratin (P<0.001). The isolated corneal and scleral fluorescence sections after DAPI staining in FIG. 4B show that no green fluorescence is seen in the blank tissue section, indicating that the tissue has no fluorescent background interference. In the cornea in vitro, compared with the wild-type penetratin group, the lipophilic penetratin derivative-treated cornea has stronger fluorescence intensity, and the stronger the lipophilicity, the more the amount of corneal entry, while the hydrophilic penetratin derivative 6A group had no obvious fluorescence signal. In the isolated sclera, the fluorescence signal of the lipophilic derivative group was stronger than that of the wild-type penetratin group, while 6A was significantly weaker than that of the penetratin group.

Example 6

(31) Evaluation of in vitro tissue toxicity of covalently linked complexes of Penetratin derivatives and small molecular substances: a portion of the tissue fixed with Davidson's solution is taken for paraffin section stained with hematoxylin-eosin (HE), then the integrity of the tissue after the permeability experiment is observed; another portion of the tissue is taken, the surface moisture of which is absorbed with filter paper, weighed and recorded as m.sub.0, and then dried in an oven at 60° C. for 48 h, recorded as m.sub.t after weighing, the tissue hydration value is calculated according to the following formula:
ΔH=(m.sub.0−m.sub.t)/m.sub.0×100%

(32) The results in FIG. 5A show that the hydration values of the cornea and sclera in vitro treated with penetratin derivatives are not significantly different from those of the untreated fresh cornea and sclera, and are consistent with normal values reported in the literature. This showed that penetratin derivatives had no toxic effect on isolated ocular tissues at the concentration of 7.5 μm.

(33) The results of HE stained sections in FIG. 5B show that all cornea treated with penetratin derivatives maintained an intact corneal epithelial structure without cavitation or damage. All sclera treated with penetratin derivatives also maintained an intact structure without fiber breakage. It shows that penetratin derivative has no toxic effect on cornea and sclera in vitro at 7.5 μM concentration.

Example 7

(34) Evaluation of intraocular distribution of the covalently linked complex of Penetratin derivatives and small molecules: 5 μL of a solution of complex of penetratin derivative and FAM (concentration 30 μM) was dripped into the conjunctival sac of male mice, and the eyelids were gently closed to distribute the solution evenly. The solution was administered every 10 minutes for a total of 3 times, and taking the time of the last administration as zero time. At a preset time point, mice were killed by intraperitoneal injection of excessive chloral hydrate, and the eyeballs of the mice were removed, fixed with Davidson's solution for 0.5 h, and embedded. Frozen longitudinal sections of eyeballs were prepared and the nuclei were stained with DAPI, and the distribution of polypeptides in the eye parts was observed under an inverted fluorescence microscope.

(35) The results in FIG. 6A show that no green fluorescence signal is observed in the anterior segment (cornea) and posterior segment (retina) of the eyeball sections of the blank group of mice, indicating that the ocular tissues have no fluorescent background interference. Compared with the wild-type penetratin group, the lipophilic penetratin derivative group had stronger green FAM fluorescence signals in the anterior segment and posterior segment of the eye after 10 minutes of eye drops, indicating that lipophilic penetratin derivative has stronger eye penetrating ability, and the FAM fluorescence signal of the hydrophilic penetratin derivative group 6A weakened, indicating that its ocular permeability is weaker than that of wild-type penetratin, which is consistent with the results of in vitro experiments. Further, FIG. 6B shows that after administration via the conjunctival sac, lipophilic penetratin derivatives could be effectively distributed in the corneal stroma and inner plexiform layer of retinal of mice, while derivative 6A is significantly less distributed in the cornea than wild-type penetratin, with almost no green fluorescence signal of FAM, and the derivative 6A is also less distributed in the retina.

(36) FIG. 6C semi-quantitative analysis results show that compared with wild-type penetratin, more lipophilic penetratin derivatives enter into the cornea and retina (p<0.001), and the retention time in the eye is longer. For derivatives 28-W, 29-W, 89-W and 289-W, which are more lipophilic, the retention time is up to 6 hours. For derivative 6A, the amount that entered into the eye was significantly less than that of wild-type penetratin (p<0.05), indicating that its permeability to the eye barrier was poor.

Example 8

(37) Preparation of non-covalent complexes of Penetratin derivatives and antisense oligonucleotide drugs: taking 60 μg of antisense oligonucleotides against transforming growth factor (TGFβ2) gene (anti-TGFβ2-ASO), adding 2 mL of buffer solution, and vortexing for 30 s to fully dissolve to obtain an ASO solution with a concentration of 30 μg/mL. Taking a 5.sup.th generation amino-terminated polyamidoamine (PAMAM, abbreviated as PG5) dendrimer in methanol 10 μL (PAMAM concentration 0.1 mg/μL), drying it with nitrogen in a 40° C. water bath, and then PAMAM was re-dissolved in 1 mL of distilled water and diluted with distilled water to obtain an experimental concentration of PAMAM solution. 1 mg of hyaluronic acid (HA) was dissolved in 1 mL of distilled water and diluted with distilled water to obtain a HA solution with a experimental concentration. Penetratin derivatives 2-M, 8-W and 9-Y (RMIKIWFWYRRMKWKK (SEQ ID NO. 68), abbreviated as Pene) were dissolved in a buffer solution to obtain a solution of a penetratin derivative with a concentration of 500 μM.

(38) 500 μL experimental concentration of PAMAM solution was added to the equal volume (500 μL) of ASO solution dropwise under vortex conditions, continue vortexing for 30 s after the dropwise addition was completed, and stabilizing the mixture at room temperature for 30 min to obtain an ASO/PG5 complex. 1 mL of the stabilized ASO/PG5 complex was added to 500 μL experimental concentration of HA solution dropwise under vortex conditions, after the dropwise addition was completed, continue vortexing for 30 s, and stabilizing the mixture at room temperature for 30 min to obtain an ASO/PG5/HA complex. 1.5 mL of the stabilized ASO/PG5/HA complex was added in 500 μL of penetratin derivative solution with a concentration of 500 μM dropwise under vortex conditions, after the dropwise addition was completed, continue vortexing for 30 s and stabilizing the mixture at room temperature for 30 min, and then ASO/PG5/HA/Pene complex was obtained.

Example 9

(39) Ocular absorption of non-covalent complexes of penetratin derivatives and antisense oligonucleotide drugs: ASO/PG5, ASO/PG5/HA and ASO/PG5/HA/Pene complexes were prepared using fluorescently labeled ASO. All experimental groups contain 30 μg/mL of ASO. The mice were randomly divided into 3 groups, namely ASO/PG5, ASO/PG5/HA and ASO/PG5/HA/Pene groups, 12 mice in each group, and the right eye was administered dropwise with 10 μL of the experimental group solution. The drug was administered every 10 minutes, and each mouse in each group was administered a total of 3 times. After 1 h, 2 h, 6 h, and 8 h after the last administration, 3 mice were randomly selected from each group and sacrificed. The eyeballs of the mouse were removed and dehydrated in a 30% sucrose solution overnight. Sectioned perpendicular to the cornea, frozen sections were taken from the middle section of the tissue and nuclear stained with DAPI working solution. The elimination of complexes in the posterior segment of the eye was observed under a confocal microscope.

(40) According to the observation results of frozen sections, all the ASO delivered by the three complexes were distributed in the posterior segment of the mouse eye after 1 h of eye drops, and the distribution is increased as time passed. However, only ASO delivered by ASO/PG5/HA/Pene showed obvious distribution in the posterior segment of the eye, and it was still distributed in the outer plexiform layer (OPL) and retinal pigment epithelium (RPE) after 8 hours. The results show that using the oligonucleotide complex modified with penetratin derivatives 2-M, 8-W, 9-Y can effectively deliver ASO to the posterior segment of the eye and distribute it in the retinal pigment epithelial (RPE) cell layer, and the retention time in the posterior segment of the eye is more than 8 hours (FIG. 7A). A comparison of the relative fluorescence intensities of the main ASO distribution layers is shown in FIG. 7B. A comparison of the relative fluorescence intensities of the main ASO distribution layers is shown in FIG. 7B.

Example 10

(41) Preparation of non-covalent complex of fluorouracil modified with Penetratin derivative and antisense oligonucleotide drug dual-loading drug: taking a 5.sup.th generation amino-terminated polyamidoamine (PAMAM, abbreviated as PG5) dendrimer in a methanol solution of 10 μL (PAMAM concentration is 0.1 mg/μL) and drying it in a 40° C. water bath with nitrogen. PAMAM was then re-dissolved in 1 mL of distilled water and diluted with distilled water to obtain a PG5 solution with a concentration of 6.23 μM. Dissolving 1 mg of fluorouracil (Fu) in 1 mL of distilled water, after 5 min in a water bath at 40° C., vortexing to dissolve, and then diluting the mother liquor with distilled water to obtain a Fu solution with the desired concentration. Adding the Fu solution dropwise to the PG5 solution and stirring for a period of time to obtain a mixed solution. Stop stirring, transferring the mixed solution to an ultrafiltration centrifuge tube with a cut-off molecular weight of 3,000 Da, and centrifuging to remove free Fu at 3,000 rpm/min to obtain a Fu/PG5 complex solution.

(42) 30 μg of anti-TGFβ2 antisense oligonucleotide (anti-TGFβ2-ASO) was added to 3 mL of the buffer solution, and vortexing for 30 s to fully dissolve it to obtain a 10 μg/mL of ASO solution. 100 μL of ASO solution was added dropwise to the equal volume of Fu/PG5 solution under vortex conditions. After the dropwise addition was completed, the vortex was continued for 30 s and allowed to stand for 30 min at room temperature to obtain a dual/PG5 complex. After the dropwise addition was completed, the vortex was continued for 30 s, and the mixture was stabilized at room temperature for 30 min to obtain a dual/PG5 complex. Under vortex conditions, 200 μL of the stabilized dual/PG5 complex was added dropwise to 100 μL of the HA solution (containing HA 20 μg/mL). After the dropwise addition was completed, the vortex was continued for 30 s, and the mixture was allowed to stand for 30 minutes at room temperature to obtain a dual/PG5/HA complex. Under vortex conditions, 300 μL of dual/PG5/HA solution was added dropwise to 100 μL of 289-Fpenetratin derivative (RFIKIWFFFRRMKWKK (SEQ ID NO. 44), abbreviated as Pene) solution at a concentration of 300 μM. After the dropwise addition was completed, the vortex was continued for 30 s, and the mixture was allowed to stand for 30 min at room temperature to obtain a dual/PG5/HA/Pene complex.

Example 11

(43) Evaluation of cell uptake of the non-covalent complex of fluorouracil modified with penetratin derivative and antisense oligonucleotide: Dual/PG5, dual/PG5/HA and dual/PG5/HA/Pene complexes were prepared by using fluorescently labeled PAMAM. Using free fluorescein FAM as a negative control, the uptake of non-covalent complex of dual loading drugs modified with Penetratin derivative in L929 cells was observed under a confocal microscope. Flow cytometry was used to quantitatively detect the uptake ratio of the three complexes.

(44) The average intracellular fluorescence intensity of non-covalent complex with dual loading drugs modified with the Penetratin derivative 289-F was significantly improved compared with other experimental groups. The statistical results showed that compared with dual/PG5 and dual/PG5/HA, the uptake efficiency of dual/PG5/HA/Pene in L929 cells has been increased by about 3 times and 1 times, respectively (FIG. 8).