ABSTRACT
Recently emerging perovskite nanocrystals (PNCs) are very attractive fluorescence nanomaterials due to their very narrow emission peak, tunable wavelength, and extremely high quantum yield, but their chemosensing, biosensing and bioimaging applications suffer from the poor stability of ordinary PNCs in aqueous media, especially in biological matrices. Recently developed water-stable 2D CsPb2Br5-encapsulated 3D CsPbBr3 PNCs (i.e., CsPbBr3/CsPb2Br5 PNCs) show extremely stable light emission in pure water, but their fluorescence is seriously quenched in aqueous media containing biological molecules due to their chemical reactions. In this work, we used a facile method to encapsulate pure water-stable CsPbBr3/CsPb2Br5 PNCs in water with SiO2 and polyethylene glycol hexadecyl ether (Brij58) into a new kind of biological environment-stable PNCs (CsPbBr3/CsPb2Br5@SiO2-Brij58). The synthesis of the target PNCs can be accomplished in a fast, easy, and green way. The obtained CsPbBr3/CsPb2Br5@SiO2-Brij58 PNCs maintain strong fluorescence emission for a long time, all in pH 7.4 PBS, BSA, and minimum essential medium, exhibiting excellent biological environment stability. Moreover, the developed biological environment-stable PNCs show good biocompatibility and have been successfully used in cell imaging. Overall, the work provides an easy, low-cost, and efficient application of PNCs in bioimaging.
Subject(s)
Calcium Compounds , Nanoparticles , Oxides , Titanium , Water , Cetomacrogol , Silicon DioxideABSTRACT
The incidences of antimicrobial resistance in particular, Methicillin-Resistant Staphylococcus aureus (MRSA) have increased during the last two decades. However, conventional dosage forms are unable to evade the barrier effect of the stratum corneum to permit deep penetration of the skin to resolve deep skin infections. There is, therefore, an urgent need for an advanced drug delivery system. Thus the study reported herein was aimed to fabricate a novasome-loaded luteolin (LUT) to improve its topical delivery and to enhance its antibacterial activity. The system was investigated for the impact of the type of surfactant, stearic acid concentration (g %), cholesterol amount (mg) and Brij 52 amount (mg) on the percent entrapment efficiency, particle size, poly-dispersity index and zeta potential. Statistical optimization of these factors was conducted using the Design-Expert® software. The optimum formulation was further in-vitro characterized by release study, differential scanning calorimetry, transmission electron microscope, x-ray diffraction and antibacterial activity. Formulation F2 composed of Span 60, 0.4 g % of stearic acid, 100 mg cholesterol and 30 mg Brij 52 was selected as the optimum formula based on the highest desirability value (0.634). F2 demonstrated enhanced antimicrobial activity with lower minimum inhibitory concentrations against a panel of MRSA clinical isolates when compared to LUT dispersion. Furthermore, the F2 formula exhibited higher anti-virulence activity by effectively inhibiting biofilm formation and suppressing α-hemolysin activity in MRSA isolates. It also demonstrated improved biosafety based on cytotoxicity assessment on human skin fibroblasts (HSF). Finally, when assessed in an in vivo skin infection mouse model, the F2 formula and commercially available fusidic acid preparation significantly reduced the microbial load of infected skin lesions compared to both the negative control and LUT dispersion-treated groups. Based on the aforementioned results, the validity of novasomes as a nano-carrier to boost in vitro and in vivo anti-MRSA activity of LUT could be affirmed.
Subject(s)
Methicillin-Resistant Staphylococcus aureus , Staphylococcal Infections , Humans , Animals , Mice , Fatty Acids, Nonesterified , Luteolin/pharmacology , Luteolin/therapeutic use , Cetomacrogol/pharmacology , Cetomacrogol/therapeutic use , Anti-Bacterial Agents , Microbial Sensitivity Tests , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiologyABSTRACT
Menaquinone-7 is a form of vitamin K2 that has been shown to have numerous healthy benefits. In this study, several surfactants were investigated to enhance the production of menaquinone-7 in Bacillus natto. Results showed that Brij-58 supplementation influenced the cell membrane via adsorption, and changed the interfacial tension of fermentation broth, while the changes in the state and the composition of the cell membrane enhanced the secretion and biosynthesis of menaquinone-7. The total production and secretion rate of menaquinone-7 increased by 48.0% and 56.2% respectively. During fermentation, the integrity of the cell membrane decreased by 82.9% while the permeability increased by 158% when the maximum secretory rate was reached. Furthermore, Brij-58 supplementation induced the stress response in bacteria, resulting in hyperpolarization of the membrane, and increased membrane ATPase activity. Finally, changes in fatty acid composition increased membrane fluidity by 30.1%. This study provided an effective strategy to enhance menaquinone-7 yield in Bacillus natto and revealed the mechanism of Brij-58 supplementation in menaquinone-7 production. KEY POINTS: ⢠MK-7 yield in Bacillus natto was significantly increased by Brij-58 supplementation. ⢠Brij-58 could be adsorbed on cell surface and change fermentation environment. ⢠Brij-58 supplementation could affect the state and composition of the cell membrane.
Subject(s)
Cetomacrogol , Soy Foods , Cetomacrogol/metabolism , Bacillus subtilis/metabolism , Vitamin K 2/metabolism , Fermentation , Dietary SupplementsABSTRACT
A green, simple and cost-effective, validated high-performance liquid chromatographic (HPLC) with UV detector has been developed an analytical method for the simultaneous determination of the most significant phenolic compounds viz. Gallic acid (GA), Quercetin (QC) and Ferulic acid (FA). The detection limit of GA, QC, FA was 0.303, 0.168, 0.0976 µg/mL and quantitation limit was 0.918, 0.051, 0.295 µg/mL, respectively. All parameters of planned validated method were carried out as per the ICH guidelines. This analytical method was applied to determine the phenolic compounds in fruits cultivated in India. Phenolic compounds in fruits extract were quantified using regression equations. This method can be scaled up to determine the alkaloids from several medicinal and poisonous plants samples in pharmaceutical, forensics and industrial areas.
Subject(s)
Cetomacrogol , Surface-Active Agents , Cetomacrogol/analysis , Chromatography, High Pressure Liquid/methods , Fruit/chemistry , Plant Extracts/chemistry , Phenols/analysis , Quercetin/analysis , Gallic Acid/analysisABSTRACT
Despite the effectiveness and high tolerability of vilazodone (VLZ) as an antidepressant, its use is still limited due to its poor solubility and food dependent absorption. This study aims to load VLZ-phospholipid complex into self-assembled micelles forming VLZ-PL mixed micelles (VLZ-PL-MM), that can enhance VLZ solubility, improve its bioavailability and reduce the pharmacokinetic variability between the fed and fasting conditions. The effect of surfactant type and concentration was assessed using four different non-ionic surfactants (Brij 58, Tween 80, Labrasol and Pluronic F127) in four different weight ratios between the drug-complex and surfactant (1:0.5, 1:1, 1:2 and 1:3 w/w). Two VLZ-PL-MM formulae prepared using Brij 58 and Labrasol in 1:3 w/w ratio were selected as optimised ones since they have the highest encapsulation efficiency (100.83 and 93.87%, respectively), a particle size below 250 nm (206.73 and 221.33 nm, respectively) and negative zeta potential values (-29.63, -17.20 mV, respectively). Lyophilisation of these formulations using 3% sucrose was successful with no statistical changes in particle size and zeta potential upon rehydration. Both formulations elicited faster and higher in-vitro drug release profiles compared to the pure drug and the marketed tablet. In addition, both selected formulae improved ex-vivo permeation across rabbit intestinal membrane compared to the pure drug and the marketed tablet, with marked superiority of the one prepared using Brij 58. The results of the in-vivo study in male albino rabbits revealed similar AUC0-24 values after the oral administration of the best achieved VLZ-PL-MM system under fed and fasted conditions (769.89 and 741.55 ng.h mL-1, respectively). On the other hand, the marketed product showed significantly lower values of the AUC0-24 relative to the VLZ-PL-MM system and there was a marked enhancement of absorption of drug from the marketed product in presence of food (244.24 and 174.96 ng.h mL-1 under fed and fasted conditions, respectively). In addition, VLZ concentrations in the brain after 24 h obtained from the selected VLZ-PL-MM were significantly higher than those obtained from marketed tablet under fed and fasted conditions. Thus, the phospholipid mixed micelles formulation enhances the oral bioavailability of the poorly soluble drug and reduces the pharmacokinetic variability between fasting and fed conditions.
Subject(s)
Micelles , Vilazodone Hydrochloride , Administration, Oral , Animals , Biological Availability , Cetomacrogol , Male , Phospholipids , Rabbits , Solubility , Surface-Active Agents , TabletsABSTRACT
Understanding nonionic surfactant-protein interactions is fundamental from both technological and scientific points of view. However, there is a complete absence of kinetic data for such interactions. We employed surface plasmon resonance (SPR) to determine the kinetic and thermodynamic parameters of bovine lactoferrin-Brij58 interactions at various temperatures under physiological conditions (pH 7.4). The adsorption process was accelerated with increasing temperature, while the desorption rate decreased, resulting in a more thermodynamically stable complex. The kinetic energetic parameters obtained for the formation of the activated complex, [bLF-Brij58], indicated that the potential energy barrier for [bLF-Brij58] formation arises primarily from the reduction in system entropy. [bLF-Brij58]â formation was entropically driven, indicating that hydrophobic interactions play a fundamental role in bLF interactions with Brij58.
Subject(s)
Cetomacrogol/metabolism , Lactoferrin/metabolism , Surface-Active Agents/metabolism , Temperature , Adsorption , Cetomacrogol/chemistry , Entropy , Hydrogen-Ion Concentration , Hydrophobic and Hydrophilic Interactions , Kinetics , Lactoferrin/chemistry , Protein Binding , Surface Plasmon Resonance , Surface-Active Agents/chemistryABSTRACT
The highly-oriented cylindrical mesoporous silica films were synthesized on the rubbing-treated polyimide by adjusting the molar ratio of the orientation-directing agent (Brij56) to the structure-directing agent (P123) as surfactants in the silica precursor solutions for guiding protein adsorption states. As a result, the diameter and the orientation degree of mesopores changed with the molar ratio of Brij56 to P123. The maximum orientation degree (93%) of cylindrical mesopores oriented in the direction perpendicular to the rubbing direction was observed when the molar ratio of Brij56 to P123 was 3. Then, the dissolution features in simulated body fluid and the protein adsorption properties of the oriented cylindrical mesoporous silica films were investigated. The silica skeletons were gradually dissolved from the upper film surfaces and subsequently, the mesopore structures were collapsed when the films were immersed for 90 min. Moreover, the protein adsorption amount and the ratio from the mono-component and two-component solutions on the films were higher than those on the unoriented cylindrical mesoporous silica films due to the formation of open-ended cylindrical mesopore shapes and sizes. In addition, the shapes of the proteins adsorbed on the films had anisotropy, which would be reflected by the cylindrical mesopore shapes generated by the dissolution of silica layers and subsequent exposure of inner mesopore surfaces. Therefore, the synthesized highly-oriented cylindrical mesoporous silica films were useful to adsorb mesoscale biomolecules such as proteins and can effectively guide their anisotropic adsorption shapes, and therefore have the potential to be used as surface-coating films of polyimide in biomedical fields.
Subject(s)
Drug Design , Proteins/chemistry , Silicon Dioxide/chemistry , Adsorption , Cetomacrogol/chemistry , Optical Phenomena , PorosityABSTRACT
Quinoline yellow (E104) dye is a food additive and generally used in cosmetics and drugs. In this work, polyethylene glycol hexa decyl ether (Brij 58) was used for the spectrophotometric determination of quinoline yellow (QY) in food and drug samples after cloud point extraction (CPE). Some parameters such as extraction temperature and time, pH, centrifuge speed, Brij 58 (surfactant) concentration, and Na2SO4 concentration were optimized using Box-Behnken design. The limit of detection (LOD) of this method was 0.0019 µgâ¯mL-1 for QY while the relative standard deviation (RSD) at low concentration levels (0.03 µgâ¯mL-1) was 1.32% (nâ¯=â¯5). Findings indicated that, this novel CPE method can be used quickly for the reproducible, selective and sensitive determination of QY dye in ordinary analysis.
Subject(s)
Cetomacrogol , Surface-Active Agents , Hydrogen-Ion Concentration , Octoxynol , Polyethylene Glycols , Quinolines , SpectrophotometryABSTRACT
Polysorbates (PSs) are common protein stabilizers used in biotherapeutic formulations. However, PSs are heterogeneous and unstable in liquid protein formulations [1,2]. The purpose of this work is to explore possible alternatives for polysorbate replacements that demonstrate superior protein protection, superior self-stability, low toxicity, and wide applicability. For this purpose, 8 non-ionic surfactants that have not yet been used as excipients in marketed biotherapeutic products were investigated with PS20/80 as the benchmark. Compared with PS20/80, Brij-58 showed better protein protection ability in the mAb1 formulation under forced degradation conditions when examined by visual inspection, SEC, and dynamic lighting scanning. Additionally, Brij-58 has a better inherent stability than PS20/80 in the protein formulation when detected by UPLC-CAD. Moreover, Brij-58 is an inert excipient that does not affect protein bioactivity and conformation. In addition, the LD50 and hemolysis concentration of Brij-58 were determined, which is relatively safe when used as a parenteral injection. Furthermore, Brij-58 was also an effective protein stabilizer for the other two antibody products (IgG4 subtype and bispecific antibody) in the shaking study. In summary, Brij-58 stands out as a promising PS replacement in biotherapeutic formulations with a safe, stable and effective protein-protection profile among candidate surfactants.
Subject(s)
Biological Products/chemistry , Cetomacrogol/chemistry , Drug Compounding/methods , Excipients/chemistry , Surface-Active Agents/chemistry , Administration, Intravenous , Animals , Antibodies, Bispecific/administration & dosage , Antibodies, Bispecific/chemistry , Antibodies, Bispecific/toxicity , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/toxicity , Biological Products/administration & dosage , Biological Products/toxicity , Cetomacrogol/toxicity , Chemistry, Pharmaceutical , Drug Stability , Excipients/toxicity , Female , HEK293 Cells , Hemolysis/drug effects , Humans , Immunoglobulin G/administration & dosage , Immunoglobulin G/chemistry , Immunoglobulin G/toxicity , Lethal Dose 50 , Male , Mice , Polysorbates/chemistry , Polysorbates/toxicity , Protein Stability , Rabbits , Surface-Active Agents/toxicity , Toxicity Tests, AcuteABSTRACT
Skin bacterial colonization/infection is a frequent cause of morbidity in patients with chronic wounds and allergic/inflammatory skin diseases. This study aimed to develop a novel approach to eradicate meticillin-resistant Staphylococcus aureus (MRSA) from human skin. To achieve this, the stability and antibacterial activity of the novel LL-37-derived peptide P10 in four ointments was compared. Results indicate that P10 is chemically stable and antibacterial in hypromellose gel and Softisan-containing cream, but not in Cetomacrogol cream (with or without Vaseline), at 4 °C for 16 months. Reduction in MRSA counts on Leiden human epidermal models (LEMs) by P10 in hypromellose gel was greater than that of the peptide in Cetomacrogol cream or phosphate buffered saline. P10 did not show adverse effects on LEMs irrespective of the ointment used, while Cetomacrogol with Vaseline and Softisan cream, but not hypromellose gel or Cetomacrogol cream, destroyed MRSA-colonized LEMs. Taking all this into account, P10 in hypromellose gel dose-dependently reduced MRSA colonizing the stratum corneum of the epidermis as well as biofilms of this bacterial strain on LEMs. Moreover, P10 dose-dependently reduced MRSA counts on ex-vivo human skin, with P10 in hypromellose gel being more effective than P10 in Cetomacrogol and Softisan creams. P10 in hypromellose gel is a strong candidate for eradication of MRSA from human skin.
Subject(s)
Anti-Bacterial Agents/pharmacology , Antimicrobial Cationic Peptides/pharmacology , Methicillin-Resistant Staphylococcus aureus/drug effects , Ointments/pharmacology , Staphylococcal Skin Infections/drug therapy , Administration, Topical , Biofilms/drug effects , Biofilms/growth & development , Cetomacrogol/pharmacology , Drug Carriers/pharmacology , Humans , Hypromellose Derivatives/pharmacology , Lipids/pharmacology , Microbial Sensitivity Tests , Petrolatum/pharmacology , Skin/microbiology , CathelicidinsABSTRACT
Thrombosis is a shared perpetrating event in the pathophysiology of several cardiovascular disorders such as ischemic stroke, venous thromboembolism, atherosclerosis, and myocardial infarction. Despite holding a wide range of ammunition in our arsenal to ameliorate such conditions, we are still facing with many stumbling blocks in the satisfactory pharmacotherapy of cardiovascular diseases among which the risk of hemorrhage and life threatening drug interactions can be highlighted. Our hypothesis focuses on mimicking the nature of platelet activation, to design a novel targeted delivery system based on the alterations of a physical parameter, the hemodynamic shear stress, to aim at the offending thrombi in an attempt to offer a noninvasive, rapid, and monitoring-free method that not only can prolong the circulation time of the cargo, but also deliver it locally and reduce both the undesirable adverse effects and drug interactions. Brij52 is our chosen candidate due to its unique non-spherical morphology after forming a niosomal vesicle. We surmised that thanks to its non-spherical shape, diverse shear rates may generate different shear stresses to its equators and axes which might result in the breakdown or at least distortion of niosomal structure under elevated shear stress. The vesicles have to be synthesized in the size of platelets or in the nano-sized scale. In order to prolong the time vesicles are circulating in the blood, PEGylation may help and to make such carriers highly selective to be only activated during pathophysiological clot formation, attachment of domain A1 von Willebrand factor can be of benefit to lead this proposed delivery system to the site of thrombus formation where shear rate exceeds those of 1000â¯s-1. There is now an emerging fast growing universal research on shear activated carriers, and the present theory is an endeavor to reach a successful treatment strategy to combat cardiovascular diseases based on the hypothesis that a non-spherical nano-carrier such as Brij 52 niosomal vesicle can be of paramount benefit to deliver current antithrombotic agents in a targeted and controlled manner in the presence of elevated shear stress of the obstructed blood vessels. With more radical advanced drug delivery systems being developed and new strategies being pursued, there will be more options in our arsenal to represent a promising avenue for achieving preventive, well-tolerated, and intelligent drug carriers to circumvent the drawbacks of antithrombotic pharmacotherapy.
Subject(s)
Blood Vessels/physiopathology , Cetomacrogol/chemistry , Drug Carriers/chemistry , Shear Strength , Thrombosis/drug therapy , Animals , Blood Platelets/drug effects , Cardiovascular Diseases/physiopathology , Hemodynamics/drug effects , Humans , Platelet Activation/drug effects , Platelet Aggregation Inhibitors/pharmacology , Pressure , Stress, Mechanical , Thrombosis/physiopathology , Vascular Diseases/drug therapy , von Willebrand Factor/metabolismABSTRACT
Condylomata acuminata (CA) or anogenital warts are benign proliferative lesions caused by low-risk human papillomaviruses (HPV). Treating CA can be very frustrating for patients and clinicians due to the high recurrence rates. Immunosuppression is associated with larger size of CA that are more frequently resistant to treatment. Surgical approaches tend to be poorly effective in the long-term because of high recurrence rates related to the persistence of HPV-infected cells. In our search to find an agent to treat intraurethral CA with minor or no side effects, we evaluated intraurethral cidofovir in two male patients, who were under immunosuppressing therapy due to organ transplantation and suffered from extensive urethral HPV lesions. Both patients underwent biopsy of the lesions and initial transurethral resection. In our first case, intraurethral cidofovir instillations were started after 2 months due to recurrence after surgical treatment. In our second case, intraurethral cidofovir was administered after surgery because of incomplete resection of extensive lesions. Because of persistent or rapidly recurrent lesions despite intraurethral cidofovir instillations, the first patient needed two additional surgical interventions while the second patient underwent one additional surgical intervention. After surgical intervention, both patients received again adjuvant cidofovir instillations without side effects. Over a period of 56 weeks, both patients received each a total of 28 instillations with cidofovir. Following 3.5 years (patient 1) of the last cidofovir instillation, no recurrences were observed in our first patient. Following 6 months of the last cidofovir instillation (patient 2), two very small recurrent lesions in the most distal part of the urethra were observed in our second patient for which he will receive a cycle of 6 cidofovir instillations in the near future. Intraurethral cidofovir is a safe, easy-to-use, well-tolerated and an effective adjuvant to surgery for extensive intraurethral CA in immunocompromised patients.
Subject(s)
Cidofovir/therapeutic use , Condylomata Acuminata/drug therapy , Condylomata Acuminata/surgery , Immunocompromised Host , Papillomaviridae/drug effects , Papillomavirus Infections/drug therapy , Administration, Topical , Adult , Biopsy , Cetomacrogol/therapeutic use , Condylomata Acuminata/pathology , Humans , Laser Therapy , Male , Middle Aged , Organ Transplantation , Papillomavirus Infections/virology , RecurrenceABSTRACT
The scale up of production processes is a major challenge in pharmaceutical industry. Using a quality by design approach, upscaling can be based on the design space, which can be assessed on a small scale. In a previous study, the critical process parameters were identified by a definitive screening design on cetomacrogol ointment. In the current study, this lab scale (0.5 kg) study was scaled up to industrial scale (2000 kg, filling 100g tubes at 75 tubes/min). A similar trend for the influence of filling temperature on ointment yield stress was found for lab and industrial scale production. Furthermore, a process window for ointment filling viscosities was established. It was shown that between 26 and 170 Pa.s ointment could be filled into tubes with a low weight variation (< 0.5% RSD) resulting in a product with a yield stress that meets the pre-set criteria. This approach was subsequently verified using several creams and ointments and showed general applicability.
Subject(s)
Cetomacrogol/chemical synthesis , Chemistry, Pharmaceutical/methods , Drug Industry/methods , Surface-Active Agents/chemical synthesis , Dosage Forms , Ointments/chemical synthesis , Temperature , ViscosityABSTRACT
The effect of the nonionic detergents Brij-98 and Brij-58 over human erythrocytes was studied through quantitative hemolysis and in Langmuir films. Hemolytic tests revealed that Brijs are stronger membrane solubilizers than Triton X-100 (TX-100), with effective detergent/lipid ratios of 0.18 and 0.37 for Brij-98 and Brij-58, respectively. Experiments with Langmuir films provided significant information on the kinetics and thermodynamics of detergent-membrane interaction. The adsorption (ka) and desorption (kd) rate constants of Brijs were lower than those of TX-100. In the case of ka, that is probably due to their larger hydrophilic head (with twice (20) the oxyethylene units of TX-100). As for the thermodynamic binding constant, the linear and longer hydrophobic acyl chains of Brijs favor their stabilization in-between the lipids, through London van der Waals forces. Consequently, Kb,m values of Brij-98 (12,500â¯M-1) and Brij-58 (19,300â¯M-1) resulted higher than TX-100 (7500â¯M-1), in agreement with results from the hemolytic tests. Furthermore, Brij-58 binds with higher affinity than Brij-98 to bilayers and monolayers, despite its shorter (palmitic) hydrocarbon chain, showing that unsaturation restrains the detergent insertion into these environments. Our results provide significant information about the mechanism of interaction between Brijs and membranes, supporting their distinct solubilization effect.
Subject(s)
Detergents/chemistry , Erythrocytes/metabolism , Lipid Bilayers/chemistry , Cetomacrogol/chemistry , Humans , Kinetics , Octoxynol/chemistry , SolubilityABSTRACT
Behaviors of cationic and nonionic mixed micelles in the form of hexadecyltrimethylammonium bromide (HDABr) and hexadecyltrimethylammonium bromide-Polyethylene glycol hexadecyl ether (C16E20), in the presence of inert salts (NaBr and 3,5-dichlorosodium benzoate), by the use of reaction probe between Pp and ionized PhSH (Pp = piperidine and PhSH = phenyl salicylate), has been reported in this work. The values of RXBr (RXBr denotes ion exchange constants obtained in the presence of micelles of different structural features) or KXBr (KXBr denotes ion exchange constants obtained in the presence of micelles of the same structural features) for 3,5-Cl2C6H3CO2- were almost the same at three different [HDABr]T (0.006, 0.010 and 0.015 M). The average value of RXBr or KXBr determined, in the presence of pure HDABr micelles, using semi empirical kinetic (SEK) method appeared to be almost 2½-fold larger (RXBr or KXBr = 198) than that in the presence of mixed HDABr-C16E20 micelles (RXBr or KXBr = 78). Rheological measurements indicated the existence of wormlike/twisted micelles and vesicle at 0.015 M pure HDABr, various [3,5-Cl2C6H3CO2Na], and 25 and 35â whereas there were evidence of only spherical micelles in the presence of mixed HDABr-C16E20 ([HDABr]T = 0.015 M and [C16E20]T = 0.006 M) at both temperatures.
Subject(s)
Bromides/chemistry , Chlorobenzoates/chemistry , Micelles , Piperidines/chemistry , Salicylates/chemistry , Sodium Compounds/chemistry , Catalysis , Cetomacrogol/chemistry , Kinetics , Quaternary Ammonium Compounds/chemistry , RheologyABSTRACT
The cross-linking of the IgA Fc receptor (FcαRI) by IgA induces release of the chemoattractant LTB4, thereby recruiting neutrophils in a positive feedback loop. IgA autoantibodies of patients with autoimmune blistering skin diseases therefore induce massive recruitment of neutrophils, resulting in severe tissue damage. To interfere with neutrophil mobilization and reduce disease morbidity, we developed a panel of specific peptides mimicking either IgA or FcαRI sequences. CLIPS technology was used to stabilize three-dimensional structures and to increase peptides' half-life. IgA and FcαRI peptides reduced phagocytosis of IgA-coated beads, as well as IgA-induced ROS production and neutrophil migration in in vitro and ex vivo (human skin) experiments. Since topical application would be the preferential route of administration, Cetomacrogol cream containing an IgA CLIPS peptide was developed. In the presence of a skin permeation enhancer, peptides in this cream were shown to penetrate the skin, while not diffusing systemically. Finally, epitope mapping was used to discover sequences important for binding between IgA and FcαRI. In conclusion, a cream containing IgA or FcαRI peptide mimetics, which block IgA-induced neutrophil activation and migration in the skin may have therapeutic potential for patients with IgA-mediated blistering skin diseases.
Subject(s)
Antigens, CD/chemistry , Autoantibodies/chemistry , Immunoglobulin A/chemistry , Neutrophil Activation/drug effects , Peptidomimetics/immunology , Peptidomimetics/metabolism , Receptors, Fc/chemistry , Administration, Topical , Antigens, CD/immunology , Antigens, CD/metabolism , Autoantibodies/immunology , Autoantibodies/metabolism , Autoimmune Diseases/therapy , Cetomacrogol/administration & dosage , Cetomacrogol/chemistry , Epitope Mapping , Half-Life , Humans , Immune System Diseases/immunology , Immunoglobulin A/immunology , Immunoglobulin A/metabolism , Leukocyte Disorders/immunology , Leukotriene B4/metabolism , Neutrophil Infiltration/drug effects , Neutrophils/drug effects , Neutrophils/immunology , Peptide Library , Peptidomimetics/chemistry , Phagocytosis , Protein Binding , Reactive Oxygen Species/metabolism , Receptors, Fc/immunology , Receptors, Fc/metabolism , Skin/drug effects , Skin/immunology , Skin/pathology , Skin Absorption , Skin Diseases/immunology , Skin Diseases/therapyABSTRACT
BACKGROUND: This work aimed to provide useful information on the incidence of the choice of formulation in semi-solid preparations of iron-oxide nanoparticles (IONs). The appropriate analytical methods to assess the IONs physical stability and the effect of the semi-solid preparations on IONs human skin penetration were discussed. The physical stability of IONs (Dh = 31 ± 4 nm; ζ = -65 ± 5 mV) loaded in five semi-solid preparations (0.3% w/v), namely Carbopol gel (CP), hydroxyethyl cellulose gel (HEC), carboxymethylcellulose gel (CMC), cetomacrogol cream (Cet) and cold cream was assessed by combining DLS and low-field pulsed NMR data. The in vitro penetration of IONs was studied using human epidermis or isolated stratum corneum (SC). RESULTS: Reversible and irreversible IONs aggregates were evidenced only in HEC and CMC, respectively. IONs diffused massively through SC preferentially by an intercellular pathway, as assessed by transmission electron microscopy. The semi-solid preparations differently influenced the IONs penetration as compared to the aqueous suspension. Cet cream allowed the highest permeation and the lowest retained amount, while cold cream and CP favored the accumulation into the skin membrane. CONCLUSION: Basic cutaneous semi-solid preparations could be used to administer IONs without affecting their permeation profile if they maintained their physical stability over time. This property is better discriminated by low-field pulsed NMR measurements than the commonly used DLS measurements.
Subject(s)
Drug Carriers/chemistry , Ferric Compounds/administration & dosage , Magnetite Nanoparticles/administration & dosage , Skin Absorption , Carboxymethylcellulose Sodium/chemistry , Cellulose/chemistry , Cetomacrogol/chemistry , Diffusion , Drug Stability , Epidermis/metabolism , Gels/chemistry , Humans , In Vitro Techniques , Microscopy, Electron, Transmission , Particle Size , Skin Cream/chemistryABSTRACT
The plasma membrane (PM) forms a barrier between a plant cell and its environment. Proteins at this subcellular location play diverse and complex roles, including perception of extracellular signals to coordinate cellular changes. Analyses of PM proteins, however, are often limited by the relatively low abundance of these proteins in the total cellular protein pool. Techniques traditionally used for enrichment of PM proteins are time consuming, tedious, and require extensive optimization. Here, we provide a simple and reproducible enrichment procedure for PM proteins from Arabidopsis thaliana seedlings starting from total microsomal membranes isolated by differential centrifugation. To enrich for PM proteins, total microsomes are treated with the nonionic detergent Brij-58 to decrease the abundance of contaminating organellar proteins. This protocol combined with the genetic resources available in Arabidopsis provides a powerful tool that will enhance our understanding of proteins at the PM.
Subject(s)
Arabidopsis Proteins/isolation & purification , Arabidopsis/chemistry , Cell Fractionation/methods , Cell Membrane/chemistry , Membrane Proteins/isolation & purification , Seedlings/chemistry , Arabidopsis/metabolism , Cell Membrane/metabolism , Centrifugation/instrumentation , Centrifugation/methods , Cetomacrogol/chemistry , Microsomes/chemistry , Microsomes/metabolism , Plant Cells/chemistry , Plant Cells/metabolism , Seedlings/metabolism , Surface-Active Agents/chemistryABSTRACT
Batch-to-batch variability is a challenge for the industrial scale production of ointments. Therefore the current investigation focussed on identifying and understanding critical process parameters (CPPs) for cetomacrogol ointment. This was evaluated using a definitive screening design (DSD) approach in which fourteen batches were produced under predefined and controlled conditions using the following variables: addition of SiO2 nanoparticles, mixing speed, cooling rate, heating temperature, container filling temperature and isothermal mixing at the filling temperature. Ointment structure was evaluated using a number of rheological parameters. One of these parameters, yield stress was found to be strongly influenced by filling temperature and mixing speed (p=0.0065 and p=0.0013 respectively). Both significantly affect ointment structure and they also have a significant interaction (p<0.05). Understanding the ointment production process can help in defining a processing window to produce ointment of constant quality.
Subject(s)
Cetomacrogol/chemistry , Ointments/chemistry , Nanoparticles/chemistry , Quality Control , Silicon Dioxide/chemistry , TemperatureABSTRACT
Evaluate the effects of nonionic surfactants Brij 58 and Tween 40 with different structures but similar hydrophilic lipophilic balances (HLBs) on theophylline (TH)-loaded ethylcellulose (EC) microspheres. Microspheres were formulated using ratios of the surfactants with matching HLB values but different chemical-structures at temperatures (22/35 °C) by hydrophobic solvent-emulsion evaporation. Particle size, GMD, drug loading, encapsulation efficiency and dissolution were evaluated. Drug release was determined using the zero- and first-order, Higuchi and Hixson-Crowell models. EC microspheres prepared with surfactant Brij 58 showed discrete, free-flowing spherical particles, solid interiors and increased particle smoothness as temperature increased; those prepared with Tween 40 appeared porous with coarser surface morphology as temperature increased; both were CHLB (Combined HLB) dependent. Dissolution obeyed the Higuchi model drug release for both microspheres prepared with Tween 40 and Brij 58 except for those prepared with Brij 58 at 35 °C, which presented as zero order. The results were ascribed to the different chemical structure of Brij 58 versus Tween 40 and preparation temperature. Surfactant chemical structure is an unreported processing parameter shown here to be important in microsphere formulation. Brij 58 possesses properties unique to its chemical structure that influence pharmaceutical and molecular biopharmaceutical research.