Serratiopeptidase Loaded Chitosan Nanoparticles by Polyelectrolyte Complexation: In Vitro and In Vivo Evaluation

The aim of the present study was to formulate serratiopeptidase (SER)-loaded chitosan (CS) nanoparticles for oral delivery. SER is a proteolytic enzyme which is very sensitive to change in temperature and pH. SER-loaded CS nanoparticles were fabricated by ionic gelation method using tripolyphosphate (TPP). Nanoparticles were characterized for its particle size, morphology, entrapment efficiency, loading efficiency, percent recovery, and in vitro dissolution study. SER-CS nanoparticles had a particle size in the range of 400–600 nm with polydispersity index below 0.5. SER association was up to 80 ± 4.2%. SER loading and CS/TPP mass ratio were the primary parameters having direct influence on SER-CS nanoparticles. SER-CS nanoparticles were freeze dried using trehalose (20%) as a cryoprotectant. In vitro dissolution showed initial burst followed by sustained release up to 24 h. In vivo anti-inflammatory activity was carried out in rat paw edema model. In vivo anti-inflammatory activity in rat paw edema showed prolonged anti-inflammatory effect up to 32 h relative to plain SER.KEY WORDS: anti-inflammatory activity, chitosan, nanoparticle, serratiopeptidase, TPP     

Organosilane and Polyethylene Glycol Functionalized Magnetic Mesoporous Silica Nanoparticles as Carriers for CpG Immunotherapy In Vitro and In Vivo

Cytosine–guanine (CpG) containing oligodeoxynucleotides (ODN) have significant clinical potential as immunotherapeutics. However, limitations exist due to their transient biological stability in vivo, lack of specificity for target cells, and poor cellular uptake. To address these issues, we prepared amine magnetic mesoporous silica nanoparticles (M-MSN-A) then further modified with polyethylene glycol (PEG) for use as CpG delivery vectors. The PEG modified M-MSN-A (M-MSN-P) had notable CpG ODN loading capacity, negligible cytotoxicity, and were easily internalized into cells where they released the loaded CpG into the cytoplasm. As a result, such complexes were effective in activating macrophages and inhibiting tumor cells when combined with chemotherapeutics in vitro. Furthermore, these complexes had excellent immuno-stimulating activity in vivo, compared to the free CpG therapeutics. We report here a highly effective MSNs-based delivery system with great potential as a therapeutic CpG formulation in cancer immunotherapy.     

In Vitro and In Vivo Evaluation of Hydroxyzine Hydrochloride Microsponges for Topical Delivery

Hydroxyzine HCl is used in oral formulations for the treatment of urticaria and atopic dermatitis. Dizziness, blurred vision, and anticholinergic responses, represent the most common side effects. It has been shown that controlled release of the drug from a delivery system to the skin could reduce the side effects while reducing percutaneous absorption. Therefore, the aim of the present study was to produce an effective drug-loaded dosage form that is able to control the release of hydroxyzine hydrochloride into the skin. The Microsponge Delivery System is a unique technology for the controlled release of topical agents, and it consists of porous polymeric microspheres, typically 10–50 μm in diameter, loaded with active agents. Eudragit RS-100 microsponges of the drug were prepared by the oil in an oil emulsion solvent diffusion method using acetone as dispersing solvent and liquid paraffin as the continuous medium. Magnesium stearate was added to the dispersed phase to prevent flocculation of Eudragit RS-100 microsponges. Pore inducers such as sucrose and pregelatinized starch were used to enhance the rate of drug release. Microsponges of nearly 98% encapsulation efficiency and 60–70% porosity were produced. The pharmacodynamic effect of the chosen preparation was tested on the shaved back of histamine-sensitized rabbits. Histopathological studies were driven for the detection of the healing of inflamed tissues.KEYWORDS: hydroxyzine HCl, microsponges, oil in oil emulsion solvent diffusion, skin delivery     

Ophthalmic Delivery of Brinzolamide by Liquid Crystalline Nanoparticles: In Vitro and In Vivo Evaluation

Brinzolamide (BLZ) is a drug used to treat glaucoma; however, its use is restricted due to some unwanted adverse events. The goal of this study was to develop BLZ-loaded liquid crystalline nanoparticles (BLZ LCNPs) and to figure out the possibility of LCNPs as a new therapeutic system for glaucoma. BLZ LCNPs were produced by a modified emulsification method and their physicochemical aspects were estimated. In vitro release study revealed BLZ LCNPs displayed to some extent prolonged drug release behavior in contrast to that of BLZ commercial product (Azopt®). The ex vivo apparent permeability coefficient of BLZ LCNP systems demonstrated a 3.47-fold increase compared with that of Azopt®. The pharmacodynamics was checked over by calculating the percentage fall in intraocular pressure and the pharmacodynamic test showed that BLZ LCNPs had better therapeutic potential than Azopt®. Furthermore, the in vivo ophthalmic irritation was evaluated by Draize test. In conclusion, BLZ LCNPs would be a promising delivery system used for the treatment of glaucoma, with advantages such as lower doses but maintaining the effectiveness, better ocular bioavailability, and patient compliance compared with Azopt®.     

Toxicity Evaluation of Chromium Picolinate Nanoparticles In Vivo and In Vitro in Rat

The toxicity of nanoCrpic is still not understood and needs further investigation. Thus, this study investigated the effect of chromium picolinate nanoparticles (nanoCrpic) on the toxicity in vivo and in vitro in rat. In the in vivo study, 36 rats (Wistar, 8-week-old) were randomly divided into the control group (fed basal diet), the low-dose (300 ppb, μg/kg), and high-dose (1,000 ppb) nanoCrpic groups. The trial was conducted for 2 months; at the final stage of the trial, the rats were sacrificed, liver and kidney were examined, and samples of tissues were taken for histological examination. Hepatocytes isolated from 10-week-old Wistar male rats were used for in vitro study to examine the degree of DNA damage following exposure to 0 and 0.294 mM of H₂O₂ for 30 min. Incubation medium was supplemented with 0 (control), 100, and 300 ppb nanoCrpic. In vivo study indicated that no lesions of liver or kidney were detected in 300 and 1,000 ppb nanoCrpic fed rats. The in vitro study evaluated DNA damage according to the percentage and distance of the fragments migration and revealed that there was insignificant difference between the nanoCrpic and control groups (p?>?0.05). This study indicated that nanoCrpic at 300–1,000 ppb in vivo and at 100–300 ppb in vitro showed no signs of toxicity to rats.     

Design and Development of Gliclazide Mucoadhesive Microcapsules: In Vitro and In Vivo Evaluation

In this study an attempt was made to prepare mucoadhesive microcapsules of gliclazide using various mucoadhesive polymers designed for oral controlled release. Gliclazide microcapsules were prepared using sodium alginate and mucoadhesive polymer such as sodium carboxymethyl cellulose (sodium CMC), carbopol 934P or hydroxy propylmethyl cellulose (HPMC) by orifice-ionic gelation method. The microcapsules were evaluated for surface morphology and particle shape by scanning electron microscope. Microcapsules were also evaluated for their microencapsulation efficiency, in vitro wash-off mucoadhesion test, in vitro drug release and in vivo study. The microcapsules were discrete, spherical and free flowing. The microencapsulation efficiency was in the range of 65–80% and microcapsules exhibited good mucoadhesive property in the in vitro wash off test. The percentage of microcapsules adhering to tissue at pH 7.4 after 6 h varied from 12–32%, whereas the percentage of microcapsules adhering to tissue at pH 1.2 after 6 h varied from 35–68%. The drug release was also found to be slow and extended for more than 16 h. In vivo testing of the mucoadhesive microcapsules in diabetic albino rats demonstrated significant antidiabetic effect of gliclazide. The hypoglycemic effect obtained by mucoadhesive microcapsules was for more than 16 h whereas gliclazide produced an antidiabetic effect for only 10 h suggesting that mucoadhesive microcapsules are a valuable system for the long term delivery of gliclazide.     

Design and In Vitro Evaluation of Finasteride-Loaded Liquid Crystalline Nanoparticles for Topical Delivery

In this study, liquid crystalline nanoparticles (LCN) have been proposed as new carrier for topical delivery of finasteride (FNS) in the treatment of androgenetic alopecia. To evaluate the potential of this nanocarrier, FNS-loaded LCN was prepared by ultrasonication method and characterized for size, shape, in vitro release, and skin permeation–retention properties. The particle size ranged from 153.8 to 170.2 nm with a cubical shape and exhibited controlled release profile with less than 20% of the drug released in the first 24 h. The release profile was significantly altered with addition of different additives. Formulation with lower monoolein exhibited higher skin permeation with a flux rate of 0.061 ± 0.005 μg cm⁻² h⁻¹ in 24 h. The permeation however, significantly increased with glycerol, propylene glycol, and polyethylene glycol 400, while it declined for the addition of oleic acid. A similar trend was observed with skin retention study. In conclusion, FNS-loaded LCN could be advocated as a viable alternative for oral administration of the drug.Key words: androgenetic alopecia, finasteride, liquid crystalline nanoparticles, release, skin permeation–retention     

Lyophilized Sustained Release Mucoadhesive Chitosan Sponges for Buccal Buspirone Hydrochloride Delivery: Formulation and In Vitro Evaluation

This work aims to prepare sustained release buccal mucoadhesive lyophilized chitosan sponges of buspirone hydrochloride (BH) to improve its systemic bioavailability. Chitosan sponges were prepared using simple casting/freeze-drying technique according to 3² factorial design where chitosan grade was set at three levels (low, medium, and high molecular weight), and concentration of chitosan solution at three levels (0.5, 1, and 2%). Mucoadhesion force, ex vivo mucoadhesion time, percent BH released after 8 h (Q8h), and time for release of 50% BH (T_50%) were chosen as dependent variables. Additional BH cup and core buccal chitosan sponge were prepared to achieve uni-directional BH release toward the buccal mucosa. Sponges were evaluated in terms of drug content, surface pH, scanning electron microscopy, swelling index, mucoadhesion strength, ex vivo mucoadhesion time, and in vitro drug release. Cup and core sponge (HCH 0.5E) were able to adhere to the buccal mucosa for 8 h. It showed Q8h of 68.89% and exhibited a uni-directional drug release profile following Higuchi diffusion model.KEY WORDS: buspirone HCL, casting/freeze-drying technique, chitosan, cup and core sponge, mucoadhesive buccal sponges     

功能化介孔二氧化硅纳米粒子在恶性肿瘤诊疗中的应用进展

介孔二氧化硅纳米粒子（mesoporous silica nanoparticles,MSNs）作为新型纳米载体在生物医药领域具有较好的应用前景,其有别于传统无机材料的物理化学性质对于当今恶性肿瘤的诊断与治疗起着关键性作用。尤其是MSNs作为一种具有高装载量、良好的生物相容性、靶向性以及对药物释放的可控性的载药平台,可用于解决目前临床上恶性肿瘤诊疗中遇到的问题。主要探讨了MSNs探针及MSNs靶向给药系统的应用进展及发展方向,以期为恶性肿瘤诊疗提供思路与参考。     

牛血红蛋白PLGA纳米粒的制备及其体外功能的研究

目的:利用poly(lactide-co-glycolide)(PLGA)和poly(styrene-co-4-styrene-sulfonate)(PSS)制备带负电荷的牛血红蛋白纳米粒,并对其载氧性能和体外性能进行评价.方法:采用溶剂蒸发法制备出空白的PLGA-PSS的空白纳米粒,通过改变pH值,吸附牛血红蛋白,从而制备出牛血红蛋白PLGA纳米粒.通过TEM、粒径、Zeta电位、包裹率和载药量、体外释放及其携氧能力对该纳米粒进行了综合分析.结果:Hb-PLGA-PSS-NPsTEM电镜下呈类球形,平均粒径为226.8±23.4nm,Zeta电位为-68.62 mV,优化条件后最大包裹率约为99.3%,载药量约为28.6%,在37℃,pH7.4的PBS溶液中释放缓慢.通过对Hb结构的分析表明此工艺未对蛋白的结构造成影响,体外携氧实验测量了P50(29mmHg)和Hill系数(2.036),结果说明该Hb纳米微囊具有良好携氧功能.结论:成功制备了一种Hb-PLGA-PSS-NPs纳米粒,稳定性好,具有很好的携氧能力.     

Mesoporous Silica Nanoparticles for Cancer Therapy: Energy-Dependent Cellular Uptake and Delivery of Paclitaxel to Cancer Cells

Biocompatible mesoporous silica nanoparticles, containing the fluorescence dye fluorescein isothiocyanate (FITC), provide a promising system to deliver hydrophobic anticancer drugs to cancer cells. In this study, we investigated the mechanism of uptake of fluorescent mesoporous silica nanoparticles (FMSN) by cancer cells. Incubation with FMSN at different temperatures showed that the uptake was higher at 37°C than at 4°C. Metabolic inhibitors impeded uptake of FMSN into cells. The inhibition of FMSN uptake by nocodazole treatment suggests that microtubule functions are required. We also report utilization of mesoporous silica nanoparticles to deliver a hydrophobic anticancer drug paclitaxel to PANC-1 cancer cells and to induce inhibition of proliferation. Mesoporous silica nanoparticles may provide a valuable vehicle to deliver hydrophobic anticancer drugs to human cancer cells.     

The Serum-Resistant Transfection Evaluation and Long-Term Stability of Gene Delivery Dry Powder Based on Mesoporous Silica Nanoparticles and Polyethyleneimine by Freezing-Drying

Mesoporous silica nanoparticles (MSNs) with large surface area, tunable pore size, and low toxicity can act as suitable vehicles for drug and gene delivery. An MSN/DNA/PEI complex delivery system was prepared by using MSNs to hold plasmid DNA coated with polyethyleneimine (PEI), and the dry powder formulation was produced by freeze-drying with trehalose as lyoprotectant. The MSN/DNA/PEI complexes successfully enhanced the gene expression with about 1.5-fold higher efficiency as compared with the control, and even better effects and lower toxicity were achieved at lower content of PEI. Also, this gene delivery system showed nearly sixfold higher efficiency in the serum-containing condition than the control, so further application of these vehicles in vivo is highly appreciated. Besides, the trehalose containing lyophilized formulation could hold the availability for at least 4 months of storing at room temperature, presenting the potential for industrial production and transportation of gene therapy.     

The Practicality of Mesoporous Silica Nanoparticles as Drug Delivery Devices and Progress Toward This Goal

Mesoporous silica nanoparticles (MSNs) have been proposed as drug delivery devices for approximately 15 years. The history of in vitro studies has been promising, demonstrating that MSNs have the capability for stimulus-responsive controlled release, good cellular uptake, cell specific targeting, and the ability to carry a variety of cargoes from hydrophobic drug molecules to imaging agents. However, the translation of the in vitro findings to in vivo conditions has been slow. Herein, we review the current state-of-the-art in the use of MSN for systemic drug delivery in vivo and provide critical insight into the future of MSNs as systemic drug delivery devices and directions that should be undertaken to improve their practicality.     

Development and Evaluation of an In Vitro System to Study Strawberry Fruit Development

Growth and ripening of strawberry (Fragariaananassa Duch.)fruit harvested at immature stages of development was accomplishedby placing the peduncles of individual fruit in solutions composedof hydroxyquinoline hemisulphate (HQS) and sucrose. Fruit cultivarand developmental stage at harvest were the major determinantsof in vitro performance. ‘Pajaro’ fruit harvestedat 50 to 60% maturity exhibited the greatest and most uniformweight gain when placed in solutions containing 200 mol m^–3HQS and 88 mol m^–3 sucrose. Although the final fruit weightof in vitro-ripened fruit was less than that of field-ripenedfruit, colour development in vitro occurred at the same rateand to the same extent as field-grown fruit. Key words: Ripening, non-climacteric fruit     

5-Fluorouracil-Loaded BSA Nanoparticles: Formulation Optimization and In Vitro Release Study

Over the past few decades, there has been considerable interest in developing protein nanoparticles as drug delivery devices. The underlying rationale is their exceptional characteristics, namely biodegradability and nonantigenicity. Herein, phase separation method was used to prepare 5-fluorouracil-loaded bovine serum albumin (BSA) nanoparticles. Drug release was tracked by continuous flow dialysis technique. Effect of process variables on loading efficiency of 5-fluorouracil was investigated and optimized through Taguchi’s M16 design with the amount of entrapped drug as response. Optimum condition was found to be 2 mg/mL of 5-fluorouracil, 3.7 mL of added ethanol, 176 μL of glutaraldehyde, drug–protein incubation time of 30 min, and pH of 8.4 for 200 mg of BSA in 2 mL drug solution. pH had the most noticeable effect on the amount of entrapped drug, but glutaraldehyde had the least. Mean diameter and zeta potential of fabricated nanoparticles under these conditions were 210 nm and −31.7 mV, respectively. Drug-loaded BSA nanoparticles suspension maintained constant release of drug for 20 h under experimental conditions, so this colloidal drug carrier is capable of releasing drug in a sustained manner.     

In Vitro Toxicity Evaluation of 25-nm Anatase TiO2 Nanoparticles in Immortalized Keratinocyte Cells

Titanium dioxide (TiO(2)) nanoparticles (NPs) are massively fabricated and widely used in daily life, and thus potential risk has been posed to human health. However, the mechanism of the interaction between TiO(2) NPs and cells is still unclear. In this study, the interaction of anatase TiO(2) NPs with HaCaT cells is studied in vitro with multi-techniques. The TiO(2) NPs not only insert into cells through endocytic pathway but also penetrate into the cell. The TiO(2) NPs could produce reactive oxygen species (ROS) after dispersion spontaneously. Furthermore, the interaction between TiO(2) NPs and cellular components might also generate ROS. The ROS generation could lead to cellular toxicity if the level of ROS production overwhelms the antioxidant defense. Cytoskeletal components, particularly the microfilaments and microtubules, cause modifications upon exposure to TiO(2) NPs. With all results, the toxicological effects of TiO(2) NPs on HaCaT cell can be simplified into six events.     

In Vitro and In Vivo Trypanocidal Activity of H2bdtc-Loaded Solid Lipid Nanoparticles

The parasite Trypanosoma cruzi causes Chagas disease, which remains a serious public health concern and continues to victimize thousands of people, primarily in the poorest regions of Latin America. In the search for new therapeutic drugs against T. cruzi, here we have evaluated both the in vitro and the in vivo activity of 5-hydroxy-3-methyl-5-phenyl-pyrazoline-1-(S-benzyl dithiocarbazate) (H₂bdtc) as a free compound or encapsulated into solid lipid nanoparticles (SLN); we compared the results with those achieved by using the currently employed drug, benznidazole. H₂bdtc encapsulated into solid lipid nanoparticles (a) effectively reduced parasitemia in mice at concentrations 100 times lower than that normally employed for benznidazole (clinically applied at a concentration of 400 µmol kg⁻¹ day⁻¹); (b) diminished inflammation and lesions of the liver and heart; and (c) resulted in 100% survival of mice infected with T. cruzi. Therefore, H₂bdtc is a potent trypanocidal agent.