Biodegradable spirulina extract/polycaprolactone porous scaffolds

2018 ◽  
Vol 42 (19) ◽  
pp. 15830-15838 ◽  
Author(s):  
Bo Shi ◽  
Liming Zhang ◽  
Liang Liang ◽  
Jianfeng Ban

Hydrophilicity, pores with interconnected structures, and degradability are important properties of tissue engineering scaffolds.

Author(s):  
Hugh Lippincott ◽  
Daniel F. Schmidt

Shape recovery from memory by porous scaffolds for tissue engineering offers easier insertion and self-retention following placement by minimally invasive surgery. Shape memory testing of porous polymer xerogels focuses on the compression cycle and the special aspects of the cycle and equipment used. This contrasts with normal tensile shape memory (SM) testing. In this work a dynamic mechanical analyzer (DMA) was used on small samples to quickly yield measurement of the SM restoration at various stress levels to emulate the forces exerted on the body by a tissue engineering (TE) scaffold returning to its permanent shape. The DMA testing of a hexamethyl diisocyanate trimer crosslinked castor oil (CO) / polycaprolactone (PCL) blend yielded repeated SM with no creep. The porous CO/PCL showed repeated compressive SM at 50% strain with a SM stress-free recovery ratio of 100%. The peak SM recovery work of 6.4 KJ/m3 was measured at 0.5 MPa stress and 6% to 12% strain. In addition to the potential utility of these materials in a tissue engineering setting, the test methods described here are relevant to a broad range of shape memory applications, from medical devices to morphing airframes to self-deploying structures.


2011 ◽  
Vol 2011 ◽  
pp. 1-19 ◽  
Author(s):  
Brahatheeswaran Dhandayuthapani ◽  
Yasuhiko Yoshida ◽  
Toru Maekawa ◽  
D. Sakthi Kumar

Current strategies of regenerative medicine are focused on the restoration of pathologically altered tissue architectures by transplantation of cells in combination with supportive scaffolds and biomolecules. In recent years, considerable interest has been given to biologically active scaffolds which are based on similar analogs of the extracellular matrix that have induced synthesis of tissues and organs. To restore function or regenerate tissue, a scaffold is necessary that will act as a temporary matrix for cell proliferation and extracellular matrix deposition, with subsequent ingrowth until the tissues are totally restored or regenerated. Scaffolds have been used for tissue engineering such as bone, cartilage, ligament, skin, vascular tissues, neural tissues, and skeletal muscle and as vehicle for the controlled delivery of drugs, proteins, and DNA. Various technologies come together to construct porous scaffolds to regenerate the tissues/organs and also for controlled and targeted release of bioactive agents in tissue engineering applications. In this paper, an overview of the different types of scaffolds with their material properties is discussed. The fabrication technologies for tissue engineering scaffolds, including the basic and conventional techniques to the more recent ones, are tabulated.


2007 ◽  
Vol 334-335 ◽  
pp. 1225-1228 ◽  
Author(s):  
Wen You Zhou ◽  
S.H. Lee ◽  
Min Wang ◽  
W.L. Cheung

This paper reports a study on the modification of a commercial selective laser sintering (SLS) machine for the fabrication of tissue engineering scaffolds from small quantities of poly(L-lactide) (PLLA) microspheres. A miniature build platform was designed, fabricated and installed in the build cylinder of a Sinterstation 2000 system. Porous scaffolds in the form of rectangular prism, 12.7×12.7×25.4 mm3, with interconnected square and round channels were designed using SolidWorks. For initial trials, DuraFormTM polyamide powder was used to build scaffolds with a designed porosity of ~70%. The actual porosity was found to be ~83%, which indicated that the sintered regions were not fully dense. PLLA microspheres in the size range of 5-30 μm were made using an oil-in-water emulsion solvent evaporation procedure and they were suitable for the SLS process. A porous scaffold was sintered from the PLLA microspheres with a laser power of 15W and a part bed temperature of 60oC. SEM examination showed that the PLLA microspheres were partially melted to form the scaffold. This study has demonstrated that it is feasible to build tissue engineering scaffolds from small amounts of biomaterials using a commercial SLS machine with suitable modifications.


2010 ◽  
Vol 133 (3) ◽  
Author(s):  
Alisa Morss Clyne

Tissue engineering requires complex three-dimensional scaffolds that mimic natural extracellular matrix function. A wide variety of techniques have been developed to create both fibrous and porous scaffolds out of polymers, ceramics, metals, and composite materials. Existing techniques include fiber bonding, electrospinning, emulsion freeze drying, solvent casting/particulate leaching, gas foaming/particulate leaching, high pressure processing, and thermally induced phase separation. Critical scaffold properties, including pore size, porosity, pore interconnectivity, and mechanical integrity, are determined by thermal processing parameters in many of these techniques. In this review, each tissue engineering scaffold preparation method is discussed, including recent advancements as well as advantages and disadvantages of the technique, with a particular emphasis placed on thermal parameters. Improvements on these existing techniques, as well as new thermal processing methods for tissue engineering scaffolds, will be needed to provide tissue engineers with finer control over tissue and organ development.


NANO ◽  
2012 ◽  
Vol 07 (04) ◽  
pp. 1230004 ◽  
Author(s):  
ZHE WANG ◽  
ZHURONG TANG ◽  
FANGZHU QING ◽  
YOULIANG HONG ◽  
XINGDONG ZHANG

To repair bone defects, an important approach is to fabricate tissue engineering scaffolds as substitutions to replace auto-/allologous bones. Currently, processing a biomaterial into three-dimensional porous scaffolds and incorporating the calcium phosphate (Ca–P) nanoparticles into scaffolds profile two main characteristics of bone tissue engineering scaffolds. Based on this fact, in this paper we describe the design principles of the Ca–P nanoparticle-based and porous bone tissue engineering scaffolds. Then we summarize a variety of the Ca–P nanoparticle-based scaffolds, including discussion of the integration of the Ca–P nanoparticles with ceramics and polymers, followed by introduction of safety of the Ca–P nanoparticles in scaffolds.


2002 ◽  
Vol 729 ◽  
Author(s):  
Kevin R. King ◽  
Chiaochun Wang ◽  
Joseph P. Vacanti ◽  
Jeffrey T. Borenstein

AbstractIn this work, we present for the first time, the fabrication of a fully biodegradable microfluidic device with features of micron-scale precision. This implantable MEMS device is a transition from poorly defined porous scaffolds to reproducible precision scaffolds with built-in convective conduits. First, conventional photolithography is used to create a master mold by bulk micromachining silicon. Next, polydimethylsiloxane (PDMS) silicone elastomer is replica molded to form a flexible inverse mold. The commonly used biodegradable polymer Poly-lactic-co-glycolic acid (PLGA 85:15) is then compression micromolded onto the PDMS to form micropatterned films of the biodegradable polymer. Finally, a thermal fusion bonding process is used to seal the biodegradable PLGA films, forming closed microfluidic channels at the capillary size-scale. Film thicknesses from 100μm-1mm are demonstrated with features having 2μm resolution and 0.2μm precision. Scanning electron micrographs of bonded biodegradable films reveal no observable bond interface and no significant pattern deformation. Bonded microfluidic channels are capable of supporting more than 30psi during flow studies, and we have used the processes to develop complex microfluidic networks for cell culture and implantation as well as simple channels to verify the fluid dynamics in the degradable microchannels. The processes described here are high resolution and fully biodegradable. In addition, they are fast, inexpensive, reproducible, and scalable, making them ideal for both rapid prototyping and manufacturing of tissue engineering scaffolds.


2012 ◽  
Vol 512-515 ◽  
pp. 1815-1820
Author(s):  
Qing Feng Zan ◽  
Yuan Zhuang ◽  
Li Min Dong ◽  
Chen Wang ◽  
Ning Wen ◽  
...  

Bone tissue engineering provides a new way to repair the bone defect in orthopaedics. The scaffolds, porous materials with excellent biocompatibility, bioactivity and biodegradability, play an important role in bone tissue engineering. Furthermore, the bioactivity of the pore interior surfaces is very important for cell attachment, differentiation and growth, as well as new bone tissue ingrowth into pores. In this paper, β-TCP was selected as materials of scaffolds, and its bioactivity was improved by activating the interior surfaces of pore walls. The porous β-TCP scaffolds with about 50~300μm of pore size and above 80% of porosity were obtained by 3D-gel-laminated processing. Their surfaces of the scaffolds were easily covered by a low crystallized bone-like apatite layer, which determined by XRD and FTIR, after immersing in 1.5SBF solution following pre-treatment by NaOH solution. MTT and ALP assays were performed after cells cultured on the porous scaffolds with bone-like structure, and the results showed higher proliferation rate and differentiation level than that on the scaffolds without treatment, which indicated that the porous β-TCP scaffolds with bone-like apatite layer on surfaces of pore walls possess higher bioactivity. Therefore, the bioactivity of tissue engineering scaffolds could be improved by deposited bone-like apatite layer on their surfaces.


2021 ◽  
Vol 22 (7) ◽  
pp. 3504
Author(s):  
Reza Zeinali ◽  
Luis J. del Valle ◽  
Joan Torras ◽  
Jordi Puiggalí

Porous biodegradable scaffolds provide a physical substrate for cells allowing them to attach, proliferate and guide the formation of new tissues. A variety of techniques have been developed to fabricate tissue engineering (TE) scaffolds, among them the most relevant is the thermally-induced phase separation (TIPS). This technique has been widely used in recent years to fabricate three-dimensional (3D) TE scaffolds. Low production cost, simple experimental procedure and easy processability together with the capability to produce highly porous scaffolds with controllable architecture justify the popularity of TIPS. This paper provides a general overview of the TIPS methodology applied for the preparation of 3D porous TE scaffolds. The recent advances in the fabrication of porous scaffolds through this technique, in terms of technology and material selection, have been reviewed. In addition, how properties can be effectively modified to serve as ideal substrates for specific target cells has been specifically addressed. Additionally, examples are offered with respect to changes of TIPS procedure parameters, the combination of TIPS with other techniques and innovations in polymer or filler selection.


Cells ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1514
Author(s):  
Nolan Wen ◽  
Enze Qian ◽  
Yunqing Kang

Although the use of porous scaffolds in tissue engineering has been relatively successful, there are still many limitations that need to be addressed, such as low vascularization, low oxygen and nutrient levels, and immune-induced inflammation. As a result, the current porous scaffolds are insufficient when treating large defects. This paper analyzed scientific research pertaining to the effects of macro-/micro-channels on the cell recruitment, vascularization, and immune response of tissue engineering scaffolds. Most of the studies contained either cell culturing experimentation or experimentation on small animals such as rats and mice. The sacrificial template method, template casting method, and 3D printing method were the most common methods in the fabrication of channeled scaffolds. Some studies combine the sacrificial and 3D printing methods to design and create their scaffold with channels. The overall results from these studies showed that the incorporation of channels within scaffolds greatly increased vascularization, reduced immune response, and was much more beneficial for cell and growth factor recruitment compared with control groups that contained no channels. More research on the effect of micro-/macro-channels on vascularization or immune response in animal models is necessary in the future in order to achieve clinical translation.


2019 ◽  
Vol 43 (25) ◽  
pp. 9989-10002 ◽  
Author(s):  
Shuang Zheng ◽  
Yonghong Guan ◽  
Haichi Yu ◽  
Ge Huang ◽  
Changjun Zheng

Ideal bone tissue engineering scaffolds should be biocompatible, biodegradable, and mechanically robust and have the ability to regulate cell function.


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