Tubular Electrospun Vancomycin-Loaded Vascular Grafts: Formulation Study and Physicochemical Characterization

This work aimed at formulating tubular grafts electrospun with a size < 6 mm and incorporating vancomycin as an antimicrobial agent. Compared to other papers, the present study succeeded in using medical healthcare-grade polymers and solvents permitted by ICH Topic Q3C (R4). Vancomycin (VMC) was incorporated into polyester synthetic polymers (poly-L-lactide-co-poly-ε-caprolactone and poly lactide-co-glycolide) using permitted solvents; moreover, a surfactant was added to the formulation in order to avoid the precipitation of VMC on fiber surface. A preliminary preformulation study was carried out to evaluate solubility of VMC in different aqueous and organic solvents and its stability. To reduce size of fibers and their orientation, we studied a solvent system based on methylene chloride and acetone (DCM/acetone), at different ratios (80:20, 70:30, and 60:40). Considering conductivity of solutions and their spinnability, solvent system at a 80:20 ratio was selected for the study. SEM images demonstrated that size of fibers, their distribution, and their orientation were affected by the incorporation of VMC and surfactant into polymer solution. Surfactant allowed for the reduction of precipitates of VMC on fiber surface, which are responsible of the high burst release in the first six hours; the release was mainly dependent on graft structure porosity, number of pores, and graft absorbent capability. A controlled release of VMC was achieved, covering a period from 96 to 168 h as a function of composition and structure; the concentration of VMC was significantly beyond VMC minimum inhibitory concentration (MIC, 2 ug/mL). These results indicated that the VMC tubular electrospun grafts not only controlled the local release of VMC, but also avoided onset of antibiotic resistance.

Preformulation Study of Pugun Tano (Curanga fel-terrae [Lour.] Merr) Ethanolic Extract Granule Mass in Capsule as Hepatoprotective Drug

BACKGROUND: Pugun tano extract had been studied for its effect as hepatoprotector. However, the usage of the plant in the form of extract has a limitation, especially if the extract is consumed by the people due to the unpleasant taste and odour. Then, the extract needs to be transformed into a particular dosage form, such as a capsule. But before the capsule can be produced, a preformulation study of pugun tano extract into a granule mass in capsule need to be evaluated. AIM: The study aimed to formulate the ethanolic extract of pugun tano (Curanga fel-terrae (Lour.) Merr) as granule mass in the capsule dosage form. METHODS: The pugun tano ethanolic extract was formulated in several steps included preparation of dry extract using coating method with polyvinylpyrrolidone (PVP) and granule mass production. The excipients used for the granule mass were lactose granules (made with tapioca starch using wet granulation), corn starch (made with 3 concentrations of 5% (F1), 7.5% (F2) and 10% (F3)), talcum, magnesium stearate, methylparaben, and propylparaben. The granule mass was evaluated for the bulk density, tapped density, inter-particle porosity, Carr’s index, Hausner ratio, angle of repose, and flowability. RESULTS: The results showed that all of the formulae passed the requirement of the preformulation test. The bulk density of the granule mass was 0.79 – 0.86 g/ml; the tapped density was 0.88 – 0.90 g/ml; the inter-particle porosity was 0.03 – 0.14; the Carr’s index was 2.71 – 11.94%; the Hausner ratio was 1.09-1.12; the angle of repose was 26.10 – 28.90°; and the flowing time was 5.97 – 6.63 seconds. All of the formulae showed good flowability and free-flowing properties. CONCLUSION: It is concluded that the obtained formula

Lipid nanostructures for antioxidant delivery: a comparative preformulation study

This investigation is a study of new lipid nanoparticles for cutaneous antioxidant delivery. Several molecules, such as α-tocopherol and retinoic acid, have been shown to improve skin condition and even counteract the effects of exogenous stress factors such as smoking on skin aging. This work describes the design and development of lipid nanoparticles containing antioxidant agents (α-tocopherol or retinoic acid) to protect human skin against pollutants. Namely, solid lipid nanoparticles and nanostructured lipid carriers were prepared using different lipids (tristearin, compritol, precirol or suppocire) in the presence or absence of caprylic/capric triglycerides. The formulations were characterized by particle size analysis, cryogenic transmission electron microscopy, small-angle X-ray diffraction, encapsulation efficiency, preliminary stability, in vitro cytotoxicity and protection against cigarette smoke. Nanostructured lipid carriers were found to reduce agglomerate formation and provided better dimensional stability, as compared to solid lipid nanoparticles, suggesting their suitability for antioxidant loading. Based on the preformulation study, tristearin-based nanostructured lipid carriers loaded with α-tocopherol were selected for ex vivo studies since they displayed superior physico-chemical properties as compared to the other nanostructured lipid carriers compositions. Human skin explants were treated with α-tocopherol-loaded nanostructured lipid carriers and then exposed to cigarette smoke, and the protein levels of the stress-induced enzyme heme oxygenase were analyzed in skin homogenates. Interestingly, it was found that pretreatment with the nanoformulation resulted in significantly reduced heme oxygenase upregulation as compared to control samples, suggesting a protective effect provided by the nanoparticles.

Extraction and Preformulation Study of Deer Antler Velvet Extract:Physical Characterization of Aqueous and Ethanol Extract

Objective: The aim of the research was to extract the deer antler velvet from Kalimantan Indonesia and to study physical characteristics between 70% ethanol and aqueous extract. Materials and methods: Ethanol extracts was extracted from deer antler velvet using maceration and modified maceration method. Ethanol extracts were compared to aqueous extract which produced using maceration technique. The extract profiles were determined by screening test and physicochemical properties as preformulation study were characterized using Thin Layer Chromatography (TLC), Nuclear Magnetic Resonance (NMR), X-ray diffractometer, differential thermal analysis (DTA), solubility test, BCA protein content, and molecular weight using SDS PAGE assay. Results: Extracts were successfully prepared and determined. Physicochemical properties of 70% ethanol extract and aqueous extract resulted different characteristics in melting point, solubility, crystallinity and protein content. Both ethanol extract and aqueous deer antler velvet extract contained group compounds of terpenoids and steroids and contains high amount of proteins at molecular weight of 17 to 43 kDa. In terms of crystallinity, ethanol and aqueous extracts had different crystal lattices. Conclusion: The aqueous extract of deer antler velvet was then recommended for further in vitro drug formulation and characterization. The molecular weight of majority protein inside aqueous deer antler velvet extract was 17 kDa and this datas will be useful for further drug formulation

Preformulation Studies of Pralidoxime Chloride for Formulation Development of Microspheres

Microspheres are one of the novel drug delivery system which possess several applications and are made up of assorted polymers. Microspheres can be defined as solid, approximately spherical particles ranging in size from 1 to 1000 μm range in diameter having a core of drug and entirely outer layers of polymers as coating material. They are made up of polymeric, waxy or other protective materials i.e. biodegradable synthetic polymer and modified natural products such as starches, gums, proteins, fats and waxes. Preformulation is a group of studies that focus on the physicochemical properties of a new drug candidate that could affect the drug performance and the development of a dosage form. This couldprovide important information for formulation design or support the need for molecular modification. Every drug has intrinsic chemical and physical properties which has been consider before development of pharmaceutical formulation. This property provides the framework for drugs combination with pharmaceutical ingredients in the fabrication of dosage form. Objective of preformulation study is to develop the elegant, stable, effective and safe dosage form by establishing kinetic rate profile, compatibility with the other ingredients and establish Physico-chemical parameter of new drug substances. The purpose of the present study was to systematically investigate some of the important physicochemical properties of pralidoxime chloride for preparation of microspheres. The physicochemical properties such as solubility, pKa, dissolution, melting point, assay development, excipient compatibility etc. of pralidoxime chloride was carried out. Before selection of excipients, the Preformulation study of drug pralidoxime is completed for successful formulation of microspheres. The result of Preformulation studies shows good flow properties, excipient compatibility, solubility efficiency and melting point. From this study we concluded that pralidoximewith HPMC and EC can be used to formulate pralidoxime microspheres for modified release. Keywords: Microspheres, Preformulation, Pralidoxime chloride, Physico-chemical parameter.

Partition Coefficient and Glutathione Penetration of Topical Antiaging:Preformulation Study

Glutathione (GSH) is a broad antioxidant of the thiol-tripeptide group, highly hydrophilic, which has limitation for topical preparations. A lipophilic surfactant is an alternative method to enhance the glutathione partition. The purpose of this study was to determine the apparent partition coefficient (APC log) of glutathione; glutathione with additional surfactant at different HLB value of HLB 4.3; 5.5; 7; 11 and selected HLB was studied for penetration. The study was conducted by dissolving glutathione in water plus various HLB surfactants. Determination method of partition coefficient was done by shake flash method. The penetration test was conducted using the parameter of decreasing Matrix Metalloproteinase-1 expression on the balb-c male skin. The results can be used as a reference for topical glutathione formulations as these results are preformulation study.