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Uveitis, a complex ocular disorder with numerous etiologies, can result from infection, autoimmune, and various physicochemical and mechanical injury factors. The treatment of this disease is difficult, and failure to receive timely and effective treatment can often lead to blindness. With the deepening of people's understanding of uveitis and its related mechanisms, various new sustained-release drug delivery systems for uveitis have been studied. However, due to the existence of various anatomical and physiological barriers in the eye, there are multiple obstacles to the sustained release treatment of uveitis. In this paper, the main research results in this field in recent years are reviewed, and the innovations and limitations of various new sustained-release drug delivery systems are discussed in order to provide new ideas for the sustained-release drug delivery treatment of uveitis in the future. These new sustained-release drug delivery systems will help to completely change the traditional treatment mode of uveitis with side effects and poor compliance in the future, bringing longer targeted sustained release and less toxic reactions.
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Objective To establish a detection method for the determination of tetrodotoxin (TTX) in sustained-release microspheres. Methods The HPLC separation of tetrodotoxin was performed on an Agilent ZORBAX SB-C18 column (4.6mm×150mm,5 μm) with acetonitrile, 8mmol/L sodium heptane sulfonate containing 0.005% TFA (5:95) (pH 4.0) as the mobile phase. The flow rate was 1.0 ml/min. The UV detection wavelength was 200 nm and the column temperature was 30 °C. Results The method had good specificity and linearity of TTX in the concentration range of 1−20 μg/ml. The intra-day precision, inter-day precision, stability and repeatability of the method were good, and the average recoveries were found between 98.0% and 102.0%. Conclusion This study established an HPLC method which was suitable for the determination of tetrodotoxin sustained-release microspheres. The method is accurate and reliable within the applicable range, with strong specificity, which could lead to quantitative detection.
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@#Chitosan-based microspheres use chitosan as the main material to obtain particles with special structures through microsphere processing technology. They have the ability of slow and controlled release of drugs and the role of scaffolding, which have great application prospect in stomatology, but the application of chitosan-based microspheres is still in the research stage and has not yet been applied in clinical practice. This article reviews progress of domestic and foreign research on chitosan-based microspheres, in aspects of treatment of oral and jawbone tissue defects, periodontal diseases, dental pulp diseases and nerve tissue injury, in order to provide reference for follow-up research.
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@#To evaluate bioequivalence and safety of two kinds of metformin hydrochloride sustained-release tablets (test preparation vs reference preparation) under the condition of fed and single administration.A single center, randomized, open, single-dose, two-period, two-sequence, and double-crossover design was used.32 healthy subjects took 0.5 g of test preparation or reference preparation under fed and single-dose administration.4 mL of venous blood was collected from before administration (0 h) to 1, 3, 4, 4.5, 5, 5.5, 6, 7, 8, 9, 10, 12, 15, 24, 36 and 48 h after administration.The concentration of metformin in plasma samples was detected, and then the pharmacokinetic parameters were calculated by WinNonlin 7.0 software.When the 90% confidence intervals of cmax, AUC0-t and AUC0-∞ geometric mean ratio of test preparation and reference preparation were within 80.00%-125.00% equivalent intervals respectively, the bioequivalence of the two preparations was proved.One subject fell off due to adverse events.The main pharmacokinetic parameters of test preparation and reference preparation as follows: cmax were (0.68 ± 0.14) and (0.65 ± 0.11) mg/L, AUC0-t were (7.33 ± 1.65) and (7.00 ± 1.89) h·mg/L, AUC0-∞ were (7.39 ± 1.67) and (7.06 ± 1.91) h·mg/L, respectively.The 90% confidence intervals of the geometric mean ratio of the two main pharmacokinetic parameters were 101.45%-109.14%, 100.08%-112.32% and 100.24%-112.28%, respectively, which fell within the bioequivalence interval of 80.00%-125.00%.There were no serious adverse events and unexpected adverse events during the trial.The results show that test preparation and reference preparation are bioequivalent under fed and single-dose administration, safe and well tolerated in healthy subjects.
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@#Antimicrobial peptides have antibacterial effects on various pathogenic microorganisms, including natural antimicrobial peptides and synthetic antimicrobial peptides. According to the structure of natural antimicrobial peptides, synthetic antimicrobial peptides can be obtained by recombining different functional domains, adjusting the original amino acid sequence, or completely redesigning the peptides from scratch. Antimicrobial peptides can inhibit the growth of various cariogenic microorganisms and the formation of microbial biofilms. They also reduce acid production and acid resistance of microorganisms. Natural antimicrobial peptide genes can be used as genetic susceptibility markers for predicting the development of caries, thus, showing potential applications in the prevention and treatment of dental caries. The instability of natural antimicrobial peptides and the inability to achieve targeted sustained release limit their application in the prevention and treatment of oral caries. Synthetic antimicrobial peptides can enhance their stability and the antibacterial effect. Synthetic antimicrobial peptides can also be polymerized with common oral adhesives to reduce the incidence of microleakage after filling treatment for caries and to prevent the occurrence of secondary caries. The pH-sensitive antimicrobial peptides are slowly released to promote remineralization in the process of caries. However, the safety and biocompatibility of synthetic antimicrobial peptides are worse than those of natural antimicrobial peptides. Moreover, the combined effect of antibacterial peptides and anticaries drugs, such as fluoride, is still uncertain. Therefore, in this paper, we will review the design methods, application and underlying mechanisms of antimicrobial peptides to introduce novel methods and ideas for the prevention and treatment of dental caries.
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Sirolimus self-microemulsion-mesoporous silicon sustained release tablets were prepared in order to improve the dissolution of the insoluble drug sirolimus and reduce its side effects. Firstly, sirolimus self-microemulsion was prepared and cured with mesoporous silicon. Secondly, the suitable excipients were selected according to the appearance, hardness and in vitro release rate. The sustained-release tablets with hydroxypropyl methylcellulose (HPMC) as skeleton material were prepared by powder direct pressing method, and the formulation was optimized by central composite design-response surface method to investigate the drug release in vitro. Finally, the pharmacokinetics was carried out in beagle dogs using the commercial sirolimus tablets as references. The final formulation of sustained-release tablets is as follows: 162 mg of sirolimus self-microemulsion-mesoporous silica (1∶1, w/w), 80 mg of HPMC K4M and 80 mg of carboxymethyl starch sodium, the microcrystalline cellulose is 168 mg. The results of in vitro release test showed that the self-made sustained-release tablets released slowly within 12 h, which conformed to the Ritger-Peppas model. The in vivo test results showed that compared with the commercial sirolimus tablets, the Cmax of the sustained-release tablets decreased by 49.47%, the Tmax of the sustained-release tablets was prolonged by 5.1 times, and the relative bioavailability was 105.81%. Sirolimus self-microemulsion-mesoporous silicon sustained-release tablets have good sustained-release effects in vitro and in vivo, which provides a reference for the solubilization of other insoluble drugs and the research and development of sustained-release preparations. Animal experiments and welfare processes were reviewed and approved by the Animal Ethics Committee of the 900TH Hospital of the Joint Logistics support Force.
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Growth hormone deficiency (GHD) has become a serious healthcare burden, and presents a huge impact on the physical and mental health of patients. Here, we developed an actively separated microneedle patch (PAA/NaHCO3-Silk MN) based on silk protein for sustained release of recombinant human growth hormone (rhGH). Silk protein, as a friendly carrier material for proteins, could be constructed in mild full-water conditions and ensure the activity of rhGH. After manually pressing PAA/NaHCO3-Silk MN patch to skin for 1 min, active separation is achieved by absorbing the interstitial fluid (ISF) to trigger HCO3 ‒ in the active backing layer to produce carbon dioxide gas (CO2). In rats, the MN patch could maintain the sustained release of rhGH for more than 7 days, and produce similar effects as daily subcutaneous (S.C.) injections of rhGH in promoting height and weight with well tolerated. Moreover, the PAA/NaHCO3-Silk MN patch with the potential of painless self-administration, does not require cold chain transportation and storage possess great economic benefits. Overall, the PAA/NaHCO3-Silk MN patch can significantly improve patient compliance and increase the availability of drugs, meet current unmet clinical needs, improve clinical treatment effects of GHD patients.
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Global burden of chronic wounds has increased drasticallyas they are vulnerable to bacterial infections that causes inflammation, thereby leads to a delay in the healing process. Furthermore, wound care and dressing industry is subjected to a global market of $30.4 billion by 2024. Our work entails fabrication of polymeric electrospun nanofibers loaded with different concentration of the amoxicillin (AMX) antibiotic. Biodegradable and biocompatible poly (vinyl) alcohol (PVA)/poly(meth)(methacrylate)(PMMA) polymerswere blended with different AMX concentration (100, 150, 200 and 250 mg) and fabricated by electrospinning technique. Morphology, structural properties and drug release from electrospun nanofibers depend on the different concentrations of drug incorporated in PVA:PMMA blend of polymer. Furthermore, these studies revealed drug-excipient compatibility and drug encapsulation within the nanofiber. In-vitro release study showed the AMX release time from PVA: PMMA: AMX was extended up to 7 days for AMX-250 with an initial burst release of 70% and further sustained drug release. Electrospun nanofibers of PVA:PMMA:AMX showed greater zone of inhibition of S. aureus as 2.1±0.4 cm for 100-AMX, 2.3±0.5 cm for 150-AMX, 2.4±0.1 for 200-AMX and 3.4±0.3 cm for 250-AMX. These results demonstrate that AMX retains the anti-bacterial activity and hence can be used as a potential wound dressing candidate.
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Abstract Sustained release matrix tablets of 100 mg losartan potassium HCl were fabricated with two release retarding polymers namely HPMC K100 M and affinisol by direct compression method. Nine trial formulations were prepared by varying content of these polymers, each from 50 mg to 100 mg; keeping the total weight of the tablet 310 mg. The best formulation was selected based on in vitro drug release profile for 12 hours conducted in Type II dissolution apparatus at 50 rpm and water as dissolution medium. Pre-compression parameters such as bulk density, tap density, Carr's index and Hausner ratio were evaluated for the selected tablet. The tablets were subjected to thickness, weight variation test, drug content, hardness and friability. Drug release kinetics, surface morphology and accelerated stability study were investigated for that selected formulation. Formulation F4 with the composition of 75 mg HPMC K100M and 100 mg affinisol was selected as the best formulation that extended the drug release up to 12 hours. Pre-compression parameters and other tableting properties were within the Pharmacopoeia limit. Release kinetics analysis proved non-fickian zero-order drug release and that was further confirmed by surface morphology of the tablets before and after dissolution study visualized by SEM. The developed formulation was found to be stable for one month stored at 60 âC.
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Tablets/analysis , In Vitro Techniques/methods , Pharmaceutical Preparations/analysis , Losartan/agonists , Drug Compounding/methods , Dissolution , Drug Liberation/drug effects , MethodsABSTRACT
Abstract Design of experiment (DoE) is a useful time and cost-effective tool for analyzing the effect of independent variables on the formulation characteristics. The aim of this study is to evaluate the effect of the process variables on the characteristics involved in the preparation of Diclofenac Sodium (DC) loaded ethylcellulose (EC) nanoparticles (NP) using Central Composite Design (CCD). NP were prepared by W/O/W emulsion solvent evaporation method. Three factors were investigated (DC/EC mass ratio, PVA concentration, homogenization speed) in order to optimize the entrapment efficiency (EE) and the particle size of NP. The optimal formulation was characterized by Fourier Transform Infrared (FTIR), Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), and in vitro release. Optimized formulation showed an EE of 49.09 % and an average particle size of 226.83 nm with a polydispersity index of 0.271. No drug-polymer interaction was observed in FTIR and DSC analysis. SEM images showed that the particles are spherical and uniform. The in vitro release study showed a sustained release nature, 53.98 % of the encapsulated drug has been released over 24hours period. This study demonstrated that statistical experimental design methodology can optimize the formulation and the process variables to achieve favorable responses.
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Pharmaceutical Preparations , Diclofenac/analysis , Process Optimization , Nanoparticles/analysis , In Vitro Techniques/instrumentation , Calorimetry, Differential Scanning/instrumentation , Microscopy, Electron, Scanning/methods , Spectroscopy, Fourier Transform Infrared , Costs and Cost Analysis/methods , Methodology as a Subject , Fourier AnalysisABSTRACT
Objective To study the release profile of curcumin and piperine from the compound self-microemulsion. Methods The release of curcumin and piperine in vitro was investigated by dynamic dialysis under the condition of phosphate buffer of pH 4.8 and 7.5 with 0.75% Tween-80. Results The cumulative release rates of curcumin in pH 4.8 and pH 7.5 were 94.85% and 84.38% in 108 h, respectively. The cumulative release rates of piperine were 92.85% and 90.05% in 36 h, separately. Conclusion Curcumin and piperine in self-microemulsion have sustained release properties and released more in the acidic environment similar to the environment in tumors.
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Objective:To investigate the efficacy of maintenance electroconvulsive therapy (MECT) combined with quetiapine treatment for manic episodes of bipolar disorder.Methods:A total of 103 patients with manic episodes of bipolar disorder received treatment in Kangci Hospital of Jiaxing from January 2019 to August 2020 and were included in this study. They were randomly divided into observation ( n = 46) and control groups ( n = 57). The observation group was given MECT combined with quetiapine treatment and the control group was treated with magnesium valproate sustained-release tablets combined with quetiapine. All patients received 4 weeks of treatment. Clinical efficacy, total hospital cost, drug cost during hospitalization, drug proportion, adverse reactions, and scores of the Bech-Rafaelsdn Mania Rating Scale and the Wisconsin Card Sorting Test pre- and post-treatment were compared between the two groups. Results:After 4 weeks of treatment, total response rate was significantly higher in the observation group than in the control group [76.09% (35/46) vs. 56.14% (32/57), χ2 = 4.45, P < 0.05]. In the observation group, total hospital cost, drug cost during hospitalization, and drug proportion were (16074.52 ± 1019.81) yuan, (1374.52 ± 619.81) yuan, and 8.70% respectively, which were not significantly different from those in the control group [(15618.14 ± 1550.34) yuan, (1261.14 ± 750.34) yuan, 10.53%, t = 1.71, 0.82, χ2 = 0.09, all P > 0.05]. After 4 weeks of treatment, Bech-Rafaelsdn Mania Rating score was significantly lower in the observation group than in the control group [(7.36 ± 3.04) points vs. (10.23 ± 2.37) points, t = 5.38, P < 0.001]. The number of wrong responses and the number of perseverative errors in the Wisconsin Card Sorting Test in the observation group were (40.45 ± 3.61) counts and (9.56 ± 1.39) counts, respectively, which were significantly lower than those in the control group [(48.59 ± 4.51) counts, (12.08 ± 1.25) counts, t = 10.17, 9.56, both P < 0.001]. The number of perseverative errors in the Wisconsin Card Sorting Test was significantly higher in the observation group than in the control group [(33.85 ± 2.50) counts vs. (29.71 ± 2.14) counts, t = 8.90, P < 0.001]. There was no significant difference in total incidence of adverse reactions between observation and control groups (21.74% vs. 22.81%, χ2 = 0.01, P > 0.05). Conclusion:MECT combined with quetiapine treatment is highly effective on the manic episodes of bipolar disorder. The combined therapy is worthy of clinical application.
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A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed to determine the plasma concentration of progesterone in Beagle dogs, and apply it to the study of the pharmacokinetics of progesterone sustained-release formulation in Beagle dogs. The plasma samples were processed by protein precipitation method and megestrol acetate was used as an internal standard (IS). The quantitation analysis was performed using multiple-reaction monitoring (MRM) mode at the specific ion transitions of m/z 315.2→97.0 for progesterone and m/z 385.2→267.1 for megestrol acetate (IS) under the positive ion condition. Male Beagle dogs were injected intramuscularly with progesterone sustained-release microspheres and the plasma samples were collected at different time points after administration. The relevant pharmacokinetic parameters were calculated by WinNonlin 8.1 software. A good linearity over the range of 0.1-500.0 ng·mL-1 was yielded by this method. The intra- and inter-day precision (RSD) were all less than 13.25% and the accuracy (RE) was within 8.92%. Stability test showed that progesterone in dog plasma was stable at room temperature for 12 h, up to 60 days at -20 ℃ and after three cycles of freeze-thaw. The recovery of it ranged from 71.43%-77.97%. After intramuscular injection of progesterone sustained-release microspheres in Beagle dogs, tmax was 19.00 ± 25.36 h, Cmax was 137.72 ± 11.59 ng·mL-1, t1/2 was 83.83 ± 26.43 h. The drug was released continuously in vivo and in a continuous absorption process for many times with good sustained-release effect. The method developed in this study is sensitive, rapid and stable. It is suitable for the determination of progesterone plasma concentration in Beagle dogs, and can be applied to the preclinical pharmacokinetic study of progesterone-related formulations. The animal experiment scheme of this study was approved by the Animal Ethics Committee of the Academy of Military Medical Sciences.
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OBJECTIVE To prepare cinnamaldehyde （CA） loaded liposomes bilayer-modified by bovine serum albumin （BSA）/chitosan （CTS）（BSA/CTS-Lip-CA） in order to improve the sustained-release effect and storage stability of the nanoparticles. METHODS Firstly，cinnamaldehyde loaded liposomes （Lip-CA）and blank liposomes （Lip-Blank）were prepared by thin film dispersion method. Then chitosan modified cinnamaldehyde loaded liposome （CTS-Lip-CA）and BSA/CTS-Lip-CA were obtained by electrostatic adsorption. Finally ， the prepared liposomes were characterized ， and their in vitro release characteristics and storage stability were investigated. RESULTS The particle size of BSA/CTS-Lip-CA was （177.8±4.0）nm and the Zeta potential was （－15.6±1.5）mV；they were in spherical shape ；FTIR analysis showed that the modification of BSA and CTS had no effect on the internal structure of liposomes. The results of in vitro drug release characteristics showed that the cumulative release of Lip-CA ，CTS-Lip-CA and BSA/CTS-Lip-CA within 10 hours were 82.9％，74.1％ and 72.9％ respectively. The results of storage stability showed that after 30 days of storage ，the particle sizes of Lip-CA ，CTS-Lip-CA and BSA/ CTS-Lip-CA were （134.2±2.1），（151.7±0.4），（164.8±1.5）nm；the retention rates of model drug CA were 65.4％，82.5％ and 90.2％ respectively. CONCLUSIONS BSA/CTS-Lip-CA is successfully prepared. It has a certain sustained-release effect and can improve the storage stability of the drug to a certain extent.
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@#In this study, different functional layer formulations and process parameters were used to prepare the levomilnacipran hydrochloride sustained-release capsules, the influence of functional layer formulation and process factors on dose dumping was studied by comparing their release curves in 40% ethanol; and the risk of dose dumping of the self-developed drug was evaluated by the similar factors of the release curve of the self-developed drug and the reference drug.The results showed that as the coating weight increased, the degree of dose dumping decreased; when the concentration of ethanol in the coating liquid solvent was less than 80%, the dose dumping increased; as the atomization pressure and maturation time increase, the dose dumping became more serious. In 0% ethanol (purified water), 5% ethanol, 20% ethanol and 40% ethanol media, the self-developed and reference preparations had the same degree of dose dumping within the specified time, and rotation speed had no significant effect on the release of metformin in vitro. In summary, formulation factors such as coating weight gain, ethanol concentration in the coating solution solvent, and process factors such as atomization pressure and curing time have a serious impact on the dose dumping of sustained-release capsules.Under the optimal functional layer formulation and process, special attention should be paid to the control of risk of self-developed dose dumping.
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@#In order to evaluate the consistency of the release behavior between the self-made saxagliptin and metformin hydrochloride sustained-release tablets and the reference preparations in vitro, the similarity of the dissolution curves between the self-made preparations and the reference preparations in four dissolution mediums: HCl (pH 1.0), acetate buffer saline (pH 4.5), phosphate buffer saline (pH 6.8) and pure water, and the gel morphology and strength of the self-made preparations and the reference preparations in the HCl (pH 1.0) solution medium were compared.Results showed that in four dissolution mediums, the dissolution rates of saxagliptin in the self-made preparations and the reference preparations at 15 min were greater than 85%, and the ?2 similarity factors of metformin hydrochloride were 89, 83, 80, 86, all greater than 50, so the dissolution of the self-made preparations was consistent with those of the reference preparations.The volume expansion rate, water absorption rate and erosion rate were consistent with those of the reference preparations, and the gel strength of the self-made preparations was the same as that of the reference preparations.The in vitro release behaviors of the self-made preparations and the reference preparations are consistent, which provide a good guarantee for bioequivalence.
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OBJECTIVE：To optimize the form ulation of Zuojin pectin c apsules，and to prepare modern Zuojin pectin capsules with protective effects against gastric ulcers. METHODS ：The formulation of Zuojin pectin capsules was optimized with orthogonal test with the contents of pectin ，soluble starch and dextrin as factors ，using formability ，moisture absorption and flow ability as indicators. Zuojin pectin capsule was prepared by wet granulation filling method with Zuojin extract powder as raw material. The contents of palmatine hydrochloride ，berberine hydrochloride ，evodiamine and rutaecarpin were evaluated by HPLC. Basket method was used to investigate the release behavior of the capsule in 0.1 mol/L HCl solution. The gastric ulcer model of rats was established by intragastric administration of 75％ ethanol. Gastric ulcer index ，the inhibition rate of gastric ulcer and the pathological sections were used as indexes to investigate the protective effect of Zuojin pectin capsules （the doses were 54，108， 216 mg/kg）on gastric ulcer. RESULTS ：The optimal formulation of Zuojin pectin capsules included 45％ pectin，12％ soluble starch，27％ dextrin and 1％ xylitol. Results of in vitro drug ， release showed that palmatine hydrochloride and berberine， hydrochloride in Zuojin pectin capsules released 53.76％ and No.54.82％ respectively within 1 h，completely released at about 8 h， and conformed to the zero-order release behavior. 2492109374@qq.com Different doses of Zuojin pectin capsule could improve the ulcer injury of gastric tissue in gastric ulcer model rats to different extent ，and significantly reduced the gastric ulcer index（P＜0.01），significantly increased the inhibition rate of gastric ulcer and the percentage of positive expression area of Schiff ’s iodate staining （P＜0.01）. CONCLUSIONS ：Zuojin pectin capsule with protective effect on gastric ulcer and certain sustained- release effect is successfully prepared.
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@#Diabetic macular edema(DME)is the foremost cause of vision impairment and even blindness in patients with diabetes mellitus. Nowadays, the approach in the treatment of DME involves laser photocoagulation, intravitreal injections of anti-VEGF agents or triamcinolone acetonide. However, they still have some limitations. In recent years, dexamethasone intravitreal implant, as a new treatment option, has brought therapeutic hope to DME patients who have poor response to other methods. Meanwhile, it has the advantages of good clinical efficacy, long duration, acceptable safety and good patient tolerability. In this paper, the research advances in dexamethasone intravitreal implant for DME are described.
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In this paper, co-processed lactose SuperTab 40 LL was selected as fillers to study the preparation of musk sustained-release mini-tablets in the Xihuang multiple-unit drug release system. Musk sustained-release tablets containing different proportions of SuperTab 40 LL and MCC were prepared under various pressures, and then the compressibility and compactibility of these prescriptions were evaluated by Walker, Heckel and Ryshkewitch-Duckworth equations. In addition, the fluidity of the prescriptions was evaluated by parameters of Kawakita equation. There was a comprehensive analysis of the effect of SuperTab 40 LL on musk sustained-release mini-tablets combined with the appearance of SuperTab 40 LL and their tensile strength. The results shown that SuperTab 40 LL had better compression process through the Heckel equation, and the direct compression process of drug powders with excipients can be analyzed by the Kawakita and Ryshkewitch-Duckworth equations. As a new type of co-processed lactose, SuperTab 40 LL had a good fluidity and compactibility. SuperTab 40 LL may undergo particle crushing and plastic deformation during the compression process, which increased the contact area and bonding sites between the particles, and aggregated and shaped the mixed powder easy. Moreover, MCC showed a synergistic effect, and the combined application with SuperTab 40 ll could effectively improve the fluidity and compressibility of the musk sustained-release powder. When the ratio of SuperTab 40 LL and MCC was 2∶1, musk sustained-release mini-tablets had a high drug loading capacity and good compactibility in line with the design objectives.
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Delayed-Action Preparations , Drug Compounding , Excipients , Fatty Acids, Monounsaturated , Models, Theoretical , Powders , TabletsABSTRACT
Objective To evaluate the pharmacokinetics of the new mesalazine enteric-coated sustained-release granules in SD rats and their distribution in the gastrointestinal tract, and to understand the preclinical pharmacokinetics and gastrointestinal distribution characteristics of the preparation. Methods Rats were administered orally to determine the drug concentrations in plasma samples and in the gastrointestinal tract. The commercially available mesalazine sustained-release granule was used as a reference to self-developed one to evaluate the process of absorption and elimination in vivo, relative bioavailability, and distribution in the gastrointestinal tract. Results The relative bioavailability of mesalazine enteric-coated sustained-release granule and non-enteric-coated one characterized by mesalazine was 89.62% ± 9.36%. After oral administration of mesalazine enteric-coated sustained-release granules, the drug has a high concentration distribution in the stomach within 2-8 hours, and gradually enters and remains in the jejunum, ileum and colon over time for 6-12 hours and then reaching a high concentration distribution in the colon. This help for the absorption of mesalazine, as well as the fixed-point release of the drug to produce a therapeutic effect. Conclusion The absorption and elimination process of mesalazine enteric sustained-release granule showed linear kinetic characteristics. There was no significant difference in pharmacokinetic parameters from the commercially available formulations, and it had a certain fluidity in the gastrointestinal tract. Good gastrointestinal distribution characteristics help the absorption of drugs in the body and the targeted release of the site of action