MyMedR

Displaying publications 261 - 280 of 307 in total

Abstract:

Sort:

Effect of duration of sonication during gelatinization on properties of tapioca starch water hyacinth fiber biocomposite

Asrofi M, Abral H, Putra YK, Sapuan SM, Kim HJ

Int J Biol Macromol, 2018 Mar;108:167-176.
PMID: 29191420 DOI: 10.1016/j.ijbiomac.2017.11.165

This paper characterizes properties of biocomposite sonicated during gelatinization. The biocomposite consisted of tapioca starch based plastic reinforced by 10% volume fraction of water hyacinth fiber (WHF). During gelatinization, the biocomposite was poured into a rectangular glass mold then vibrated in an ultrasonic bath using 40kHz, 250W for varying durations (0, 15, 30, and 60min). The resulting biocomposite was then dried in a drying oven at 50°C for 20h. The results of this study indicate that a biocomposite with optimal properties can be produced using tapioca starch and WHF if the gelatinizing mixture is exposed to ultrasound vibration for 30min. After this vibration duration, tensile strength (TS) and tensile modulus (TM) increased 83% and 108%. A further 60min vibration only increased the TS at 13% and TM at 23%. Moisture resistance of the biocomposite after vibration increased by around 25% reaching a maximal level after 30min. Thermal resistance of the vibrated biocomposites was also increased.

Matched MeSH terms: Tensile Strength
Fulltext Characterization, drug loading and antibacterial activity of nanohydroxyapatite/polycaprolactone (nHA/PCL) electrospun membrane

Hassan MI, Sultana N

3 Biotech, 2017 Aug;7(4):249.
PMID: 28714045 DOI: 10.1007/s13205-017-0889-0

Considering the important factor of bioactive nanohydoxyapatite (nHA) to enhance osteoconductivity or bone-bonding capacity, nHA was incorporated into an electrospun polycaprolactone (PCL) membrane using electrospinning techniques. The viscosity of the PCL and nHA/PCL with different concentrations of nHA was measured and the morphology of the electrospun membranes was compared using a field emission scanning electron microscopy. The water contact angle of the nanofiber determined the wettability of the membranes of different concentrations. The surface roughness of the electrospun nanofibers fabricated from pure PCL and nHA/PCL was determined and compared using atomic force microscopy. Attenuated total reflectance Fourier transform infrared spectroscopy was used to study the chemical bonding of the composite electrospun nanofibers. Beadless nanofibers were achieved after the incorporation of nHA with a diameter of 200-700 nm. Results showed that the fiber diameter and the surface roughness of electrospun nanofibers were significantly increased after the incorporation of nHA. In contrast, the water contact angle (132° ± 3.5°) was reduced for PCL membrane after addition of 10% (w/w) nHA (112° ± 3.0°). Ultimate tensile strengths of PCL membrane and 10% (w/w) nHA/PCL membrane were 25.02 ± 2.3 and 18.5 ± 4.4 MPa. A model drug tetracycline hydrochloride was successfully loaded in the membrane and the membrane demonstrated good antibacterial effects against the growth of bacteria by showing inhibition zone for E. coli (2.53 ± 0.06 cm) and B. cereus (2.87 ± 0.06 cm).

Matched MeSH terms: Tensile Strength
Fulltext Effects of plasticizer concentrations on functional properties of chicken skin gelatin films

Nor, M.H.M., Nazmi, N.N.M., Sarbon, N.M.

International Food Research Journal, 2017;24(5):1910-1918.
MyJurnal

The aim of this study was to investigate the functional properties of chicken skin gelatin films with varied concentrations of a hydrophilic plasticizer. Gelatin film solutions with different glycerol concentrations A(control), B(5%), C(10%), D(15%) and E(20%), were stirred at 45°C for 20min and oven dried at 45°C. Film characterization determination were included, tensile strength (TS), elongation at break (EAB), water vapor permeability (WVP), solubility, transparency, moisture content, Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Diffraction (X-RD). Glycerol added resulted in improvement of TS and WVP properties. Film B (5% glycerol) demonstrated low EAB (106%), WVP (0.0175 g.mm/h.m2.k.Pa) and solubility (58.64%), but with high TS (3.64 MPa), moisture content (16.0%), UV light transmission (0.04%) and transparency (0.81) compared to films C, D and E. FTIR spectrum analyses demonstrated an aliphatic alcohol group only for Film E (20% glycerol). Hence, chicken skin gelatin film at 5% glycerol concentration showed the most promising potential for industrial food processing applications.

Matched MeSH terms: Tensile Strength
E-beam sterilizable thermoplastics elastomers for healthcare devices: Mechanical, morphology, and in vivo studies

Balaji AB, Ratnam CT, Khalid M, Walvekar R

J Biomater Appl, 2018 03;32(8):1049-1062.
PMID: 29298552 DOI: 10.1177/0885328217750476

The effect of electron beam radiation on ethylene-propylene diene terpolymer/polypropylene blends is studied as an attempt to develop radiation sterilizable polypropylene/ethylene-propylene diene terpolymer blends suitable for medical devices. The polypropylene/ethylene-propylene diene terpolymer blends with mixing ratios of 80/20, 50/50, 20/80 were prepared in an internal mixer at 165°C and a rotor speed of 50 rpm/min followed by compression molding. The blends and the individual components were radiated using 3.0 MeV electron beam accelerator at doses ranging from 0 to 100 kGy in air and room temperature. All the samples were tested for tensile strength, elongation at break, hardness, impact strength, and morphological properties. After exposing to 25 and 100 kGy radiation doses, 50% PP blend was selected for in vivo studies. Results revealed that radiation-induced crosslinking is dominating in EPDM dominant blends, while radiation-induced degradation is prevailing in PP dominant blends. The 20% PP blend was found to be most compatible for 20-60 kGy radiation sterilization. The retention in impact strength with enhanced tensile strength of 20% PP blend at 20-60 kGy believed to be associated with increased compatibility between PP and EPDM along with the radiation-induced crosslinking. The scanning electron micrographs of the fracture surfaces of the PP/EPDM blends showed evidences consistent with the above contentation. The in vivo studies provide an instinct that the radiated blends are safe to be used for healthcare devices.

Matched MeSH terms: Tensile Strength
Enhanced performance with elastic resistance during the eccentric phase of a countermovement jump

Aboodarda SJ, Yusof A, Abu Osman NA, Thompson MW, Mokhtar AH

Int J Sports Physiol Perform, 2013 Mar;8(2):181-7.
PMID: 23428490

To identify the effect of additional elastic force on the kinetic and kinematic characteristics, as well as the magnitude of leg stiffness, during the performance of accentuated countermovement jumps (CMJs).

Matched MeSH terms: Tensile Strength
Effect of suturing on the mechanical properties of bovine pericardium--implications for cardiac valve bioprosthesis

Lim KO, Cheong KC

Med Eng Phys, 1994 Nov;16(6):526-30.
PMID: 7858787

In the fabrication of a bioprosthetic heart valve from bovine pericardial tissues, the tissues are subjected to suturing. The stress-strain response of sutured as well as unsutured strips of this tissue were examined. The stress-strain response was determined using a tensile-testing machine. It was found that suturing weakens the tissue in that sutured strips are more extensible, exhibit a lower stress at rupture and a lower final elastic modulus. In addition, it was also found that the bigger the suture/needle size used the greater the decrease in tissue strength. In all, tissue strength was observed to decrease by 22 to 59% in this study. The weakening of the tissue is attributed to the puncture holes created by the surgeon's needle which create regions of weakness. This response of bovine pericardial tissue to suturing should be given due consideration in the fabrication of a bioprosthetic heart valve using this tissue.

Matched MeSH terms: Tensile Strength
Development of a bioactive dentin adhesive resin modified with magnesium-doped synthetic hydroxyapatite crystals

Daood U, Fawzy A

J Mech Behav Biomed Mater, 2023 Apr;140:105737.
PMID: 36827934 DOI: 10.1016/j.jmbbm.2023.105737

The aim is to evaluate the development of an experimental multi-mode/Universal resin-based dentin adhesive modified with synthetic Mg2+ doped hydroxyapatite crystals (HAp) having self-remineralization and antibiofilm properties. HAp doped with Mg2+ was prepared by the precipitation method. Experimental adhesives were subjected to degree of conversion and X-ray diffraction test for size and crystal structure. Bond strength was tested, and electron microscopy (SEM/TEM) imaging of resin-dentin interface was done along with nanoleakage, nanoindentation, confocal and Raman analyses. S. mutans was analysed using CLSM images against modified adhesive specimens. Nucleating abilities within the resin-dentin specimens are determined by measuring Ca2+. Alkaline phosphatase, Runx2, and Ocn transcripts are amplified using quantitative polymerase chain reaction (q-PCR). A calcium assay is performed to quantify level of mineralisation. When compared to control adhesives, the 0.5% Hap/Mg2+ containing experimental dentin adhesive demonstrated improved interaction with dentin. The preservation of uniform intact hybrid layer with the absence of nanoleakage indicated dentin bond integrity with 0.5% HAP/Mg2+ modified adhesive. Self-remineralization and antibiofilm potentials are supported.

Matched MeSH terms: Tensile Strength
Fulltext The Impact of Halloysite on the Thermo-Mechanical Properties of Polymer Composites

Gaaz TS, Sulong AB, Kadhum AAH, Al-Amiery AA, Nassir MH, Jaaz AH

Molecules, 2017 May 20;22(5).
PMID: 28531126 DOI: 10.3390/molecules22050838

Nanotubular clay minerals, composed of aluminosilicate naturally structured in layers known as halloysite nanotubes (HNTs), have a significant reinforcing impact on polymer matrixes. HNTs have broad applications in biomedical applications, the medicine sector, implant alloys with corrosion protection and manipulated transportation of medicines. In polymer engineering, different research studies utilize HNTs that exhibit a beneficial enhancement in the properties of polymer-based nanocomposites. The dispersion of HNTs is improved as a result of pre-treating HNTs with acids. The HNTs' percentage additive up to 7% shows the highest improvement of tensile strength. The degradation of the polymer can be also significantly improved by doping a low percentage of HNTs. Both the mechanical and thermal properties of polymers were remarkably improved when mixed with HNTs. The effects of HNTs on the mechanical and thermal properties of polymers, such as ultimate strength, elastic modulus, impact strength and thermal stability, are emphasized in this study.

Matched MeSH terms: Tensile Strength
Fulltext Cellulose nanocrystals/ZnO as a bifunctional reinforcing nanocomposite for poly(vinyl alcohol)/chitosan blend films: fabrication, characterization and properties

Azizi S, Ahmad MB, Ibrahim NA, Hussein MZ, Namvar F

Int J Mol Sci, 2014 Jun 18;15(6):11040-53.
PMID: 24945313 DOI: 10.3390/ijms150611040

In this study, cellulose nanocrystals/zinc oxide (CNCs/ZnO) nanocomposites were dispersed as bifunctional nano-sized fillers into poly(vinyl alcohol) (PVA) and chitosan (Cs) blend by a solvent casting method to prepare PVA/Cs/CNCs/ZnO bio-nanocomposites films. The morphology, thermal, mechanical and UV-vis absorption properties, as well antimicrobial effects of the bio-nanocomposite films were investigated. It demonstrated that CNCs/ZnO were compatible with PVA/Cs and dispersed homogeneously in the polymer blend matrix. CNCs/ZnO improved tensile strength and modulus of PVA/Cs significantly. Tensile strength and modulus of bio-nanocomposite films increased from 55.0 to 153.2 MPa and from 395 to 932 MPa, respectively with increasing nano-sized filler amount from 0 to 5.0 wt %. The thermal stability of PVA/Cs was also enhanced at 1.0 wt % CNCs/ZnO loading. UV light can be efficiently absorbed by incorporating ZnO nanoparticles into a PVA/Cs matrix, signifying that these bio-nanocomposite films show good UV-shielding effects. Moreover, the biocomposites films showed antibacterial activity toward the bacterial species Salmonella choleraesuis and Staphylococcus aureus. The improved physical properties obtained by incorporating CNCs/ZnO can be useful in variety uses.

Matched MeSH terms: Tensile Strength
Fulltext A Novel Coated Suture Displays Antimicrobial Activity Without Compromising Structural Properties

Daood U, Ilyas MS, Ashraf M, Akbar M, Asif A, Khan AS, et al.

J Oral Maxillofac Surg, 2024 Sep;82(9):1147-1162.
PMID: 38830601 DOI: 10.1016/j.joms.2024.05.004

BACKGROUND: Treated or coated sutures promise to prevent contamination of wounds.
PURPOSE: The purpose of the study was to coat surgical sutures with a new quaternary ammonium silane (QAS) antimicrobial compound at two different application temperatures and then to evaluate the resulting structural, physical, mechanical, and biological properties.
STUDY DESIGN, SETTING, SAMPLE: In vitro and in vivo studies were conducted using male albino Wistar rats approved by the Joint Ethical Committee of IMU and Postgraduate Medical Institute, Lahore. Only suture samples, coated uniformly with verified presence of the compound and of adequate length were used. Samples which were not coated uniformly and with inadequate length or damaged were excluded.
PREDICTOR VARIABLE: Predictor variables were sutures with and without QAS coatings and different temperatures. Sutures were coated with QAS at 0.5 and 1.0% wt/vol using the dip coating technique and sutures with and without QAS coating were tested at 25 and 40 °C temperatures.
MAIN OUTCOME VARIABLE(S): Outcome variables of structural and physico-mechanical properties of QAS-coated and non-coated sutures were measured using Fourier transform infrared spectroscopy (for structural changes), confocal laser and scanning electron (for diameter changes), and tensile strength/modulus (for mechanical testing). Biologic outcome variables were tested (bacterial viability); macrophage cultures from Wistar rats were tested (M1/M2 polarization detecting IL-6 and IL-10). Macrophage cells were analyzed with CD80+ (M1) and CD163+ (M2). Chemotaxis index was calculated as a ratio of quantitative fluorescence of cells.
COVARIATES: Not applicable.
ANALYSES: Ordinal data among groups were compared using the Wilcoxon Mann-Whitney U test along with the comparison of histological analysis using the Wilcoxon Sign-rank test (P strength/modulus was observed for 0.5% QAS-coated samples which also had significantly higher antibacterial characteristics than other sutures (P

Matched MeSH terms: Tensile Strength
Fabrication and mechanical properties of Al2O3/SiC/ZrO2 functionally graded material by electrophoretic deposition

Askari E, Mehrali M, Metselaar IH, Kadri NA, Rahman MM

J Mech Behav Biomed Mater, 2012 Aug;12:144-50.
PMID: 22732480 DOI: 10.1016/j.jmbbm.2012.02.029

This study describes the synthesis of Al(2)O(3)/SiC/ZrO(2) functionally graded material (FGM) in bio-implants (artificial joints) by electrophoretic deposition (EPD). A suitable suspension that was based on 2-butanone was applied for the EPD of Al(2)O(3)/SiC/ZrO(2), and a pressureless sintering process was applied as a presintering. Hot isostatic pressing (HIP) was used to densify the deposit, with beneficial mechanical properties after 2 h at 1800 °C in Ar atmosphere. The maximum hardness in the outer layer (90 vol.% Al(2)O(3)+10 vol.% SiC) and maximum fracture toughness in the core layer (75 vol.% Al(2)O(3)+10 vol.% SiC + 15 vol.% ZrO(2)) composite were 20.8±0.3 GPa and 8±0.1 MPa m(1/2), respectively. The results, when compared with results from Al(2)O(3)/ZrO(2) FGM, showed that SiC increased the compressive stresses in the outer layers, while the inner layers were under a residual tensile stress.

Matched MeSH terms: Tensile Strength
Wavelet neural networks applied to pulping of oil palm fronds

Zainuddin Z, Wan Daud WR, Pauline O, Shafie A

Bioresour Technol, 2011 Dec;102(23):10978-86.
PMID: 21996481 DOI: 10.1016/j.biortech.2011.09.080

In the organosolv pulping of the oil palm fronds, the influence of the operational variables of the pulping reactor (viz. cooking temperature and time, ethanol and NaOH concentration) on the properties of the resulting pulp (yield and kappa number) and paper sheets (tensile index and tear index) was investigated using a wavelet neural network model. The experimental results with error less than 0.0965 (in terms of MSE) were produced, and were then compared with those obtained from the response surface methodology. Performance assessment indicated that the neural network model possessed superior predictive ability than the polynomial model, since a very close agreement between the experimental and the predicted values was obtained.

Matched MeSH terms: Tensile Strength
Fulltext Characterization of oral disintegrating film containing donepezil for Alzheimer disease

Liew KB, Tan YT, Peh KK

AAPS PharmSciTech, 2012 Mar;13(1):134-42.
PMID: 22167416 DOI: 10.1208/s12249-011-9729-4

The aim of this study was to develop a taste-masked oral disintegrating film (ODF) containing donepezil, with fast disintegration time and suitable mechanical strength, for the treatment of Alzheimer's disease. Hydroxypropyl methylcellulose, corn starch, polyethylene glycol, lactose monohydrate and crosspovidone served as the hydrophilic polymeric bases of the ODF. The uniformity, in vitro disintegration time, drug release and the folding endurance of the ODF were examined. The in vitro results showed that 80% of donepezil hydrochloride was released within 5 minutes with mean disintegration time of 44 seconds. The result of the film flexibility test showed that the number of folding time to crack the film was 40 times, an indication of sufficient mechanical property for patient use. A single-dose, fasting, four-period, eight-treatment, double-blind study involving 16 healthy adult volunteers was performed to evaluate the in situ disintegration time and palatability of ODF. Five parameters, namely taste, aftertaste, mouthfeel, ease of handling and acceptance were evaluated. The mean in situ disintegration time of ODF was 49 seconds. ODF containing 7 mg of sucralose were more superior than saccharin and aspartame in terms of taste, aftertaste, mouthfeel and acceptance. Furthermore, the ODF was stable for at least 6 months when stored at 40°C and 75% relative humidity.

Matched MeSH terms: Tensile Strength
Fulltext Synthesis of Radiation Curable Palm Oil-Based Epoxy Acrylate: NMR and FTIR Spectroscopic Investigations

Salih AM, Ahmad MB, Ibrahim NA, Dahlan KZ, Tajau R, Mahmood MH, et al.

Molecules, 2015;20(8):14191-211.
PMID: 26248072 DOI: 10.3390/molecules200814191

Over the past few decades, there has been an increasing demand for bio-based polymers and resins in industrial applications, due to their potential lower cost and environmental impact compared with petroleum-based counterparts. The present research concerns the synthesis of epoxidized palm oil acrylate (EPOLA) from an epoxidized palm oil product (EPOP) as environmentally friendly material. EPOP was acrylated by acrylic acid via a ring opening reaction. The kinetics of the acrylation reaction were monitored throughout the reaction course and the acid value of the reaction mixture reached 10 mg KOH/g after 16 h, indicating the consumption of the acrylic acid. The obtained epoxy acrylate was investigated intensively by means of FTIR and NMR spectroscopy, and the results revealed that the ring opening reaction was completed successfully with an acrylation yield about 82%. The UV free radical polymerization of EPOLA was carried out using two types of photoinitiators. The radiation curing behavior was determined by following the conversion of the acrylate groups. The cross-linking density and the hardness of the cured EPOLA films were measured to evaluate the effect of the photoinitiator on the solid film characteristics, besides, the thermal and mechanical properties were also evaluated.

Matched MeSH terms: Tensile Strength
The wound healing properties of Channa striatus-cetrimide cream-- tensile strength measurement

Baie SH, Sheikh KA

J Ethnopharmacol, 2000 Jul;71(1-2):93-100.
PMID: 10904151

Channa striatus, a fresh water snakehead fish, is reported to enhance dermal wound healing. Biochemical components such as amino acids and fatty acids are important for the synthesis of collagen fibers during wound healing. Arachidonic acid, a precursor of prostaglandin plays a vital role in healing the wounds. Haruan (C. striatus) contains all the essential amino acids for wound healing particularly glycine as well as high contents of arachidonic acid and polyunsaturated fatty acids that can promote prostaglandin synthesis. In the present work we have studied the wound healing effect of C. striatus in Sprague-Dawley rats. Cream formulations having different haruan fish extract concentrations as the active ingredient were prepared and stabilized, and they were applied to the wounds. The healing of wounds was characterized by an increase in the tensile strength of the skin, determined on the 7th post-operative day in each case. Haruan treatment of wounds promotes remodeling of collagen, by the synthesis of inter- and intra-molecular protein crosslinking and thus produces a marked increase (P<0.05) in tensile strength as compared to the cetrimide treated group. On the basis of our experiment we conclude that C. striatus helps in wound healing as indicated by the increase in tensile strength. We hypothesise that this effect may be due to its high content of arachidonic acid, glycine and polyunsaturated fatty acids. The mechanism of wound healing will be investigated in future studies.

Matched MeSH terms: Tensile Strength
Polymeric films as vehicle for buccal delivery: swelling, mechanical, and bioadhesive properties

Peh KK, Wong CF

J Pharm Pharm Sci, 1999 May-Aug;2(2):53-61.
PMID: 10952770

To investigate the suitability of an SCMC (sodium carboxymethyl cellulose/polyethylene glycol 400/carbopol 934P) and an HPMC (hydroxypropylmethyl cellulose/polyethylene glycol 400/carbopol 934P) films as drug vehicle for buccal delivery.

Matched MeSH terms: Tensile Strength
Fulltext Enhanced gastrointestinal survivability of recombinant Lactococcus lactis using a double coated mucoadhesive film approach

Tan EW, Tan KY, Phang LV, Kumar PV, In LLA

PLoS One, 2019;14(7):e0219912.
PMID: 31335895 DOI: 10.1371/journal.pone.0219912

Vaccine administration via the oral route is preferable to parenteral routes due to ease of administration. To date, most available oral vaccines comprises of live attenuated pathogens as oppose to peptide-based vaccines due to its low bioavailability within the gastrointestinal (GI) tract. Over the years, probiotic-based peptide delivery vehicles comprising of lactic acid bacteria such as Lactococcus lactis has emerged as an interesting alternative due to its generally recognized as safe (GRAS) status, a fully sequenced genome, transient gut colonization time, and is an efficient cellular factory for heterologous protein production. However, its survivability through the GI tract is low, thus better delivery approaches are being explored to improve its bioavailability. In this study, we employ the incorporation of a double coated mucoadhesive film consisting of sodium alginate and Lycoat RS 720 film as the inner coat. The formulated film exhibits good mechanical properties of tensile strength and percent elongation for manipulation and handling with an entrapment yield of 93.14±2.74%. The formulated mucoadhesive film is subsequently loaded into gelatin capsules with an outer enteric Eudragit L100-55 coating capable of a pH-dependent breakdown above pH 5.5 to protect against gastric digestion. The final product and unprotected controls were subjected to in vitro simulated gastrointestinal digestions to assess its survivability. The product demonstrated enhanced protection with an increase of 69.22±0.67% (gastric) and 40.61±8.23% (intestinal) survivability compared to unprotected controls after 6 hours of sequential digestion. This translates to a 3.5 fold increase in overall survivability. Owing to this, the proposed oral delivery system has shown promising potential as a live gastrointestinal vaccine delivery host. Further studies involving in vivo gastrointestinal survivability and mice immunization tests are currently being carried out to assess the efficacy of this novel oral delivery system in comparison to parenteral routes.

Matched MeSH terms: Tensile Strength
Potential of using multiscale corn husk fiber as reinforcing filler in cornstarch-based biocomposites

Ibrahim MIJ, Sapuan SM, Zainudin ES, Zuhri MYM

Int J Biol Macromol, 2019 Oct 15;139:596-604.
PMID: 31381916 DOI: 10.1016/j.ijbiomac.2019.08.015

In this study, biodegradable composite films were prepared by using thermoplastic cornstarch matrix and corn husk fiber as a reinforcing filler. The composite films were manufactured via a casting technique using different concentrations of husk fiber (0-8%), and fructose as a plasticizer at a fixed amount of 25% for starch weight. The Physical, thermal, morphological, and tensile characteristics of composite films were investigated. The findings indicated that the incorporation of husk fiber, in general, enhanced the performance of the composite films. There was a noticeable reduction in the density and moisture content of the films, and soil burial assessment showed less resistance to biodegradation. The morphological images presented a consistent structure and excellent compatibility between matrix and reinforcement, which reflected on the improved tensile strength and young modulus as well as the crystallinity index. The thermal stability of composite films has also been enhanced, as evidenced by the increased onset decomposition temperature of the reinforced films compared to neat film. Fourier transform infrared analysis revealed increasing in intermolecular hydrogen bonding following fiber loading. The composite materials prepared using corn husk residues as reinforcement responded to community demand for agricultural and polymeric waste disposal and added more value to waste management.

Matched MeSH terms: Tensile Strength
A review on the orthotics and prosthetics and the potential of kenaf composites as alternative materials for ankle-foot orthosis

Shahar FS, Hameed Sultan MT, Lee SH, Jawaid M, Md Shah AU, Safri SNA, et al.

J Mech Behav Biomed Mater, 2019 11;99:169-185.
PMID: 31357064 DOI: 10.1016/j.jmbbm.2019.07.020

Since ancient Egypt, orthosis was generally made from wood and then later replaced with metal and leather which are either heavy, bulky, or thick decreasing comfort among the wearers. After the age of revolution, the manufacturing of products using plastics and carbon composites started to spread due to its low cost and form-fitting feature whereas carbon composite were due to its high strength/stiffness to weight ratio. Both plastic and carbon composite has been widely applied into medical devices such as the orthosis and prosthesis. However, carbon composite is also quite expensive, making it the less likely material to be used as an Ankle-Foot Orthosis (AFO) material whereas plastics has low strength. Kenaf composite has a high potential in replacing all the current materials due to its flexibility in controlling the strength to weight ratio properties, cost-effectiveness, abundance of raw materials, and biocompatibility. The aim of this review paper is to discuss on the possibility of using kenaf composite as an alternative material to fabricate orthotics and prosthetics. The discussion will be on the development of orthosis since ancient Egypt until current era, the existing AFO materials, the problems caused by these materials, and the possibility of using a Kenaf fiber composite as a replacement of the current materials. The results show that Kenaf composite has the potential to be used for fabricating an AFO due to its tensile strength which is almost similar to polypropylene's (PP) tensile strength, and the cheap raw material compared to other type of materials.

Matched MeSH terms: Tensile Strength
The synergistic effects of cinnamon essential oil and nano TiO2 on antimicrobial and functional properties of sago starch films

Arezoo E, Mohammadreza E, Maryam M, Abdorreza MN

Int J Biol Macromol, 2020 Aug 15;157:743-751.
PMID: 31805325 DOI: 10.1016/j.ijbiomac.2019.11.244

This study describes a sago starch-based film by incorporation of cinnamon essential oil (CEO) and nano titanium dioxide (TiO2-N). Different concentrations (i.e., 0%, 1%, 3%, and 5%, w/w) of TiO2-N and CEO (i.e., 0%, 1%, 2%, and 3%, v/w) were incorporated into sago starch film, and the physicochemical, barrier, mechanical, and antimicrobial properties of the bionanocomposite films were estimated. Incorporation of CEO into the sago starch matrix increased oxygen and water vapor permeability of starch films while increasing TiO2-N concentration decreased barrier properties. Moisture content also decreased from 12.96% to 8.04%, solubility in water decreased from 25% to 13.7%, and the mechanical properties of sago starch films improved. Sago starch bionanocomposite films showed excellent antimicrobial activity against Escherichia coli, Salmonella typhimurium, and Staphylococcus aureus. Results also showed that incorporation of TiO2-N and CEO had synergistic effects on functional properties of sago starch films. In summary, sago starch films incorporated with both TiO2-N and CEO shows potential application for active packaging in food industries such as fresh pistachio packaging.

Matched MeSH terms: Tensile Strength

Filters

Please provide feedback to Administrator ([email protected])

External Links