Anahita Rohani Shirvan

Bio: Anahita Rohani Shirvan is an academic researcher from Amirkabir University of Technology. The author has contributed to research in topics: Buccal administration & Electrospinning. The author has an hindex of 3, co-authored 7 publications receiving 41 citations.

Fabrication of multifunctional mucoadhesive buccal patch for drug delivery applications.

Abstract: Mucoadhesive buccal patch is a promising dosage form for a successful oral drug delivery, which provides unique advantages for various applications such as treatment of periodontal disease and postdental surgery disorders. The aim of this study is to synthesize a novel multifunctional mucoadhesive buccal patch in a multilayer reservoir design for therapeutic applications. The patches were fabricated through simultaneous electrospinning of chitosan/poly(vinylalcohol) (PVA)/ibuprofen and electrospraying of phenylalanine amino acid nanotubes (PhNTs) containing metronidazole into the electrospun mats through a layer-by-layer process. An electrospun poly(caprolactone) (PCL) was used as an impermeable backing layer to protect the mucoadhesive component from tongue movement and drug loss. Buccal patches were characterized using scanning electron microscopy (SEM) and field emission scanning electron microscopy (FESEM) and also evaluated in terms of physicomechanical parameters such as pH, weight, thickness, tensile strength, folding endurance, and mucoadhesive properties. The swelling index of the patches was examined with respect to the PVA/chitosan ratio. The effect of genipin addition to the electrospinning solution was also studied on mucoadhesive and swelling properties. The cell viability of buccal patches was assessed by methylthiazolydiphenyl-tetrazolium bromide test on L929 fibroblast cell line. The patch with an optimal amount of mucoadhesive polymers (PVA/chitosan 80:20) and crosslinking agent (0.05 g) indicated an ideal hemostatic activity along with antibacterial properties against Streptococcus mutans bacteria. The synthesized multifunctional mucoadhesive patch with a novel composition and design has a great potential for oral therapeutic applications.

Environmentally friendly Finishing of Cotton Fabric via Star-like Silver micro/nano Particles Synthesized with Neem/Salep

Abstract: In this study, a novel silver solution was prepared by a simple green synthesis method using AgNO3, neem and salep extracts at room temperature. The results of UV-Visible spectrophotometer and Scan...

Structural polymer biomaterials

Abstract: Polymeric biomaterials are widely used in the biomedical field because of their ease of fabrication, flexibility, and biocompatibility, as well as their wide range of mechanical, chemical, and thermal behaviors. Structural polymeric biomaterials are one of the most important groups of biomaterials and have gained much interest in biomedical applications where the materials must withstand a high load without deformation and fracturing. This chapter begins with a discussion of the fundamental concepts related to structural properties, followed by an introduction of a number of structural biopolymers. Polyester, polyethylene, polypropylene, poly(methyl methacrylate), polyether ether ketone, and polyurethane are the most commonly used biopolymers for load-bearing applications, such as bone fracture repairs, cranioplasty, hip and knee arthroplasty, spinal applications, orthopedic devices, and dental implants. Different types of structural polymeric scaffolds, their additive manufacturing techniques, and structural medical applications are also reviewed in this chapter.

Additive manufacturing

Abstract: Propulsion system development requires new, more affordable manufacturing techniques and technologies in a constrained budget environment, while future in-space applications will require in-space manufacturing and assembly of parts and systems. Marshall is advancing cuttingedge commercial capabilities in additive and digital manufacturing and applying them to aerospace challenges. The Center is developing the standards by which new manufacturing processes and parts will be tested and qualified. Rapidly evolving digital tools, such as additive manufacturing, are the leading edge of a revolution in the design and manufacture of space systems that enables rapid prototyping and reduces production times. Marshall has unique expertise in leveraging new digital tools, 3D printing, and other advanced manufacturing technologies and applying them to propulsion systems design and other aerospace materials to meet NASA mission and industry needs. Marshall is helping establish the standards and qualifications “from art to part” for the use of these advanced techniques and the parts produced using them in aerospace or elsewhere in the U.S. industrial base.

Biomedical applications of biodegradable polymers

Abstract: Utilization of polymers as biomaterials has greatly impacted the advancement of modern medicine. Specifically, polymeric biomaterials that are biodegradable provide the significant advantage of being able to be broken down and removed after they have served their function. Applications are wide ranging with degradable polymers being used clinically as surgical sutures and implants. To fit functional demand, materials with desired physical, chemical, biological, biomechanical, and degradation properties must be selected. Fortunately, a wide range of natural and synthetic degradable polymers has been investigated for biomedical applications with novel materials constantly being developed to meet new challenges. This review summarizes the most recent advances in the field over the past 4 years, specifically highlighting new and interesting discoveries in tissue engineering and drug delivery applications.

Discrete element modeling of powder flow and laser heating in direct metal laser sintering process

Abstract: A novel particle-based discrete element model (DEM) is developed to simulate the whole Direct Metal Laser Sintering (DMLS) process, which includes simplified powder deposition, recoating, laser heating, and holding stages This model is first validated through the simulation of particle flow and heat conduction in the powder bed, and the simulated results are in good agreement with either experiment in the literature or finite element method Then the validated model is employed to the DMLS process The effects of laser power, laser scan speed, and hatch spacing on the temperature distributions in the powder bed are investigated The results demonstrate that the powder bed temperature rises as the laser power is increased Increasing laser scan speed and laser hatch spacing will not affect the average temperature increase in the powder bed since energy input is kept same However, a large hatch spacing may cause non-uniform temperature distribution and microstructure inhomogeneity The model developed in this study can be used as a design and optimization tool for DMLS process