Displaying publications 21 - 40 of 84 in total

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  1. Rennukka M, Sipaut CS, Amirul AA
    Biotechnol Prog, 2014 Nov-Dec;30(6):1469-79.
    PMID: 25181613 DOI: 10.1002/btpr.1986
    This work aims to shed light in the fabrication of poly(3-hydroxybutyrate-co-44%-4-hydroxybutyrate)[P(3HB-co-44%4HB)]/chitosan-based silver nanocomposite material using different contents of silver nanoparticle (SNP); 1-9 wt%. Two approaches were applied in the fabrication; namely solvent casting and chemical crosslinking via glutaraldehyde (GA). A detailed characterization was conducted in order to yield information regarding the nanocomposite material. X-ray diffraction analysis exhibited the nature of the three components that exist in the nanocomposite films: P(3HB-co-4HB), chitosan, and SNP. In term of mechanical properties, tensile strength, and elongation at break were significantly improved up to 125% and 22%, respectively with the impregnation of the SNP. The melting temperature of the nanocomposite materials was increased whereas their thermal stability was slightly changed. Scanning electron microscopy images revealed that incorporation of 9 wt% of SNP caused agglomeration but the surface roughness of the material was significantly improved with the loading. Staphylococcus aureus and Escherichia coli were completely inhibited by the nanocomposite films with 7 and 9 wt% of SNP, respectively. On the other hand, degradation of the nanocomposite materials outweighed the degradation of the pure copolymer. These bioactive and biodegradable materials stand a good chance to serve the vast need of biomedical applications namely management and care of wound as wound dressing.
    Matched MeSH terms: Polyesters/chemistry
  2. Sanyang ML, Sapuan SM, Jawaid M, Ishak MR, Sahari J
    Carbohydr Polym, 2016 08 01;146:36-45.
    PMID: 27112848 DOI: 10.1016/j.carbpol.2016.03.051
    The development and characterization of environmentally friendly bilayer films from sugar palm starch (SPS) and poly(lactic acid) (PLA) were conducted in this study. The SPS-PLA bilayer films and their individual components were characterized for their physical, mechanical, thermal and water barrier properties. Addition of 50% PLA layer onto 50% SPS layer (SPS50-PLA50) increased the tensile strength of neat SPS film from 7.74 to 13.65MPa but reduced their elongation at break from 46.66 to 15.53%. The incorporation of PLA layer significantly reduced the water vapor permeability as well as the water uptake and solubility of bilayer films which was attributed to the hydrophobic characteristic of the PLA layer. Furthermore, scanning electron microscopy (SEM) image of SPS50-PLA50 revealed lack of strong interfacial adhesion between the SPS and PLA. Overall, the incorporation of PLA layer onto SPS films enhances the suitability of SPS based films for food packaging.
    Matched MeSH terms: Polyesters/chemistry*
  3. Yuan X, Amarnath Praphakar R, Munusamy MA, Alarfaj AA, Suresh Kumar S, Rajan M
    Carbohydr Polym, 2019 Feb 15;206:1-10.
    PMID: 30553301 DOI: 10.1016/j.carbpol.2018.10.098
    Natural polymer guar gum has one of the highest viscosities in water solution and hence, these are significantly used in pharmaceutical applications. Guar gum inter-connected micelles as a new carrier has been developed for poor water soluble rifampicin drug. The hydrogel inter-connected micelle core was formulated as a hydrophilic inner and hydrophobic outer core by using guar gum/chitosan/polycaprolactone and the carrier interaction with rifampicin was confirmed by FT-IR. The morphological observations were carried out through TEM, SEM and AFM analysis. The encapsulation efficiency and in-vitro drug release behavior of prepared hydrogel based micelle system was analyzed by UV-vis spectrometry. The anti-bacterial activity against K. pneumoniae and S. aureus was studied by observing their ruptured surface by SEM. The cytotoxicity study reveals that the pure polymeric system has no toxic effect whereas drug loaded ones showed superior activity against THP-1 cells. From the cell apoptosis analyses, the apoptosis was carried out in a time dependent manner. The cell uptake behavior was also observed in THP-1 cells which indicate that the hydrogel based micelle system is an excellent material for the mucoadhesive on intracellular alveolar macrophage treatment.
    Matched MeSH terms: Polyesters/chemistry
  4. Dasan YK, Bhat AH, Ahmad F
    Carbohydr Polym, 2017 Feb 10;157:1323-1332.
    PMID: 27987839 DOI: 10.1016/j.carbpol.2016.11.012
    The current research discusses the development of poly (lactic acid) (PLA) and poly-(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) reinforced nanocrystalline cellulose bionanocomposites. The nanocrystalline cellulose was derived from waste oil palm empty fruit bunch fiber by acid hydrolysis process. The resulting nanocrystalline cellulose suspension was then surface functionalized by TEMPO-mediated oxidation and solvent exchange process. Furthermore, the PLA/PHBV/nanocrystalline cellulose bionanocomposites were produced by solvent casting method. The effect of the addition of nanocrystalline cellulose on structural, morphology, mechanical and barrier properties of bionanocomposites was investigated. The results revealed that the developed bionanocomposites showed improved mechanical properties and decrease in oxygen permeability rate. Therefore, the developed bio-based composite incorporated with an optimal composition of nanocrystalline cellulose exhibits properties as compared to the polymer blend.
    Matched MeSH terms: Polyesters/chemistry*
  5. Muhammad KB, Abas WA, Kim KH, Pingguan-Murphy B, Zain NM, Akram H
    Clinics (Sao Paulo), 2012;67(6):629-38.
    PMID: 22760903
    OBJECTIVE: Dark poly(caprolactone) trifumarate is a successful candidate for use as a bone tissue engineering scaffold. Recently, a white polymeric scaffold was developed that shows a shorter synthesis time and is more convenient for tissue-staining work. This is an in vitro comparative study of both the white and dark scaffolds.

    METHODS: Both white and dark poly(caprolactone) trifumarate macromers were characterized via Fourier transform infrared spectroscopy before being chemically cross-linked and molded into disc-shaped scaffolds. Biodegradability was assessed by percentage weight loss on days 7, 14, 28, 42 and 56 (n = 5) after immersion in 10% serum-supplemented medium or distilled water. Static cell seeding was employed in which isolated and characterized rat bone marrow stromal cells were seeded directly onto the scaffold surface. Seeded scaffolds were subjected to a series of biochemical assays and scanning electron microscopy at specified time intervals for up to 28 days of incubation.

    RESULTS: The degradation of the white scaffold was significantly lower compared with the dark scaffold but was within the acceptable time range for bone-healing processes. The deoxyribonucleic acid and collagen contents increased up to day 28 with no significant difference between the two scaffolds, but the glycosaminoglycan content was slightly higher in the white scaffold throughout 14 days of incubation. Scanning electron microscopy at day 1 [corrected] revealed cellular growth and attachment.

    CONCLUSIONS: There was no cell growth advantage between the two forms, but the white scaffold had a slower biodegradability rate, suggesting that the newly synthesized poly(caprolactone) trifumarate is more suitable for use as a bone tissue engineering scaffold.

    Matched MeSH terms: Polyesters/chemistry*
  6. Raghavendran HR, Mohan S, Genasan K, Murali MR, Naveen SV, Talebian S, et al.
    Colloids Surf B Biointerfaces, 2016 Mar 1;139:68-78.
    PMID: 26700235 DOI: 10.1016/j.colsurfb.2015.11.053
    Scaffolds with structural features similar to the extracellular matrix stimulate rapid osteogenic differentiation in favorable microenvironment and with growth factor supplementation. In this study, the osteogenic potential of electrospun poly-l-lactide/hydroxyapatite/collagen (PLLA/Col/HA, PLLA/HA and PLLA/Col) scaffolds were tested in vitro with the supplementation of platelet derived growth factor-BB (PDGF-BB). Cell attachment and topography, mineralization, extracellular matrix protein localization, and gene expression of the human mesenchymal stromal cells were compared between the fibrous scaffolds PLLA/Col/HA, PLLA/Col, and PLLA/HA. The levels of osteocalcin, calcium, and mineralization were significantly greater in the PLLA/Col/HA and PLLA/HA compared with PLLA/Col. High expression of fibronectin, intracellular adhesion molecule, cadherin, and collagen 1 (Col1) suggests that PLLA/Col/HA and PLLA/HA scaffolds had superior osteoinductivity than PLLA/Col. Additionally, osteopontin, osteocalcin, osterix, Runt-related transcription factor 2 (Runx2), and bone morphogenic protein (BMP2) expression were higher in PLLA/Col/HA and PLLA/HA compared with PLLA/Col. In comparison with PLLA/Col, the PLLA/Col/HA and PLLA/HA scaffolds presented a significant upregulation of the genes Runx2, Col 1, Integrin, osteonectin (ON), bone gamma-carboxyglutamic acid-containing protein (BGALP), osteopontin (OPN), and BMP2. The upregulation of these genes was further increased with PDGF-BB supplementation. These results show that PDGF-BB acts synergistically with PLLA/Col/HA and PLLA/HA to enhance the osteogenic differentiation potential. Therefore, this combination can be used for the rapid expansion of bone marrow stromal cells into bone-forming cells for tissue engineering.
    Matched MeSH terms: Polyesters/chemistry
  7. Othman R, Vladisavljević GT, Thomas NL, Nagy ZK
    Colloids Surf B Biointerfaces, 2016 May 01;141:187-195.
    PMID: 26852102 DOI: 10.1016/j.colsurfb.2016.01.042
    Paracetamol (PCM)-loaded composite nanoparticles (NPs) composed of a biodegradable poly(d,l-lactide) (PLA) polymer matrix filled with organically modified montmorillonite (MMT) nanoparticles were fabricated by antisolvent nanoprecipitation in a microfluidic co-flow glass capillary device. The incorporation of MMT in the polymer improved both the drug encapsulation efficiency and the drug loading, and extended the rate of drug release in simulated intestinal fluid (pH 7.4). The particle size increased on increasing both the drug loading and the concentration of MMT in the polymer matrix, and decreased on increasing the aqueous to organic flow rate ratio. The drug encapsulation efficiency in the NPs was higher at higher aqueous to organic flow rate ratio due to faster formation of the NPs. The PCM-loaded PLA NPs containing 2 wt% MMT in PLA prepared at an aqueous to organic flow rate ratio of 10 with an orifice size of 200 μm exhibited a spherical shape with a mean size of 296 nm, a drug encapsulation efficiency of 38.5% and a drug loading of 5.4%. The encapsulation of MMT and PCM in the NPs was confirmed by transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis and attenuated total reflection-Fourier transform infrared spectroscopy.
    Matched MeSH terms: Polyesters/chemistry*
  8. Baba Ismail YM, Ferreira AM, Bretcanu O, Dalgarno K, El Haj AJ
    Colloids Surf B Biointerfaces, 2017 Nov 01;159:445-453.
    PMID: 28837894 DOI: 10.1016/j.colsurfb.2017.07.086
    This paper presents a new approach in assembling bone extracellular matrix components onto PLA films, and investigates the most favourable environment which can be created using the technique for cell-material interactions. Poly (lactic acid) (PLA) films were chemically modified by covalently binding the poly(ethylene imine) (PEI) as to prepare the substrate for immobilization of polyelectrolyte multilayers (PEMs) coating. Negatively charged polyelectrolyte consists of well-dispersed silicon-carbonated hydroxyapatite (SiCHA) nanopowders in hyaluronic acid (Hya) was deposited onto the modified PLA films followed by SiCHA in collagen type I as the positively charged polyelectrolyte. The outermost layer was finally cross-linked by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrocholoride and N-hydroxysulfosuccinimide sodium salt (EDC/NHS) solutions. The physicochemical features of the coated PLA films were monitored via X-ray Photoelectron Spectroscopy (XPS) and Atomic Force Microscope (AFM). The amounts of calcium and collagen deposited on the surface were qualitatively and quantitatively determined. The surface characterizations suggested that 5-BL has the optimum surface roughness and highest amounts of calcium and collagen depositions among tested films. In vitro human mesenchymal stem cells (hMSCs) cultured on the coated PLA films confirmed that the coating materials greatly improved cell attachment and survival compared to unmodified PLA films. The cell viability, cell proliferation and Alkaline Phosphatase (ALP) expression on 5-BL were found to be the most favourable of the tested films. Hence, this newly developed coating materials assembly could contribute to the improvement of the bioactivity of polymeric materials and structures aimed to bone tissue engineering applications.
    Matched MeSH terms: Polyesters/chemistry*
  9. Vijayan V, Shalini K, Yugesvaran V, Yee TH, Balakrishnan S, Palanimuthu VR
    Curr Pharm Des, 2018;24(28):3366-3375.
    PMID: 30179118 DOI: 10.2174/1381612824666180903110301
    BACKGROUND: Triple-Negative Breast Cancer is an aggressive type of breast cancer, which is not treatable by chemotherapy drugs, due to the lack of Estrogen Receptor (ER), Progesterone Receptor (PR) expression and Human Epidermal Growth Factor Receptor 2 (HER2) on the cell surface.

    OBJECTIVE: The aim of this study was to compare the effect of paclitaxel loaded PLGA nanoparticle (PTX-NPs) on the cytotoxicity and apoptosis of the different MDA-MB type of cell lines.

    METHOD: PTX-NPs were prepared by nanoprecipitation method and characterized earlier. The cytotoxicity of PTX-NPs was evaluated by MTT and LDH assay, later apoptosis was calculated by flow cytometry analysis.

    RESULTS: The prepared NP size of 317.5 nm and zetapontial of -12.7 mV showed drug release of 89.1 % at 48 h. MDA-MB-231 type cell showed significant cytotoxicity by MTT method of 47.4 ± 1.2 % at 24 h, 34.6 ± 0.8 % at 48 h and 23.5 ± 0.5 % at 72 h and LDH method of 35.9 ± 1.5 % at 24 h, 25.4 ± 0.6 % at 48 h and 19.8 ± 2.2 % at 72 h with apoptosis of 47.3 ± 0.4 %.

    CONCLUSION: We have found that PTX-NPs showed the cytotoxic effect on all the MDA-MB cancer cell lines and showed potent anticancer activities against MDA-MB-231 cell line via induction of apoptosis.

    Matched MeSH terms: Polyesters/chemistry*
  10. Syafiq IM, Huong KH, Shantini K, Vigneswari S, Aziz NA, Amirul AA, et al.
    Enzyme Microb Technol, 2017 Mar;98:1-8.
    PMID: 28110659 DOI: 10.1016/j.enzmictec.2016.11.011
    Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] copolymer is noted for its high biocompatibility, which makes it an excellent candidate for biopharmaceutical applications. The wild-type Cupriavidus sp. USMAA1020 strain is able to synthesize P(3HB-co-4HB) copolymers with different 4HB monomer compositions (up to 70mol%) in shaken flask cultures. Combinations of 4HB carbon precursors consisting of 1,6-hexanediol and γ-butyrolactone were applied for the production of P(3HB-co-4HB) with different 4HB molar fraction. A sharp increase in 4HB monomer composition was attained by introducing additional copies of PHA synthase gene (phaC), responsible for P(3HB-co-4HB) polymerization. The phaC of Cupriavidus sp. USMAA1020 and Cupriavidus sp. USMAA2-4 were cloned and heterologously introduced into host, wild-type Cupriavidus sp. USMAA1020. The gene dosage treatment resulted in the accumulation of 93mol% 4HB by the transformant strains when grown in similar conditions as the wild-type USMAA1020. The PHA synthase activities for both transformants were almost two-fold higher than the wild-type. The ability of the transformants to produce copolymers with high 4HB monomer composition was also tested in large scale production system using 5L and 30L bioreactors with a constant oxygen mass transfer rate. The 4HB monomer composition could be maintained at a range of 83-89mol%. The mechanical and thermal properties of copolymers improved with increasing 4HB monomer composition. The copolymers produced could be tailored for specific biopharmaceutical applications based on their properties.
    Matched MeSH terms: Polyesters/chemistry
  11. Sologashvili T, Saat SA, Tille JC, De Valence S, Mugnai D, Giliberto JP, et al.
    Eur J Pharm Biopharm, 2019 Jun;139:272-278.
    PMID: 31004790 DOI: 10.1016/j.ejpb.2019.04.012
    OBJECTIVE: Vascular prostheses for small caliber bypass grafts in cardiac and vascular diseases or for access surgery are still missing. Poly (Ɛ-caprolactone) (PCL) has been previously investigated by our group and showed good biocompatibility and mechanical properties in vitro and rapid endothelialisation, cellular infiltration and vascularisation in vivo yielding optimal patency in the abdominal aortic position. The aim of the present study is to evaluate our PCL graft in the carotid position and to compare its outcome to the grafts implanted in the abdominal aortic position.

    METHODS: PCL grafts (1 mm ID/10 mm long) were implanted into the left common carotid artery in 20 Sprague-Dawley rats and compared to our previously published series of abdominal aortic implants. The animals were followed up to 3, 6, 12 and 24 weeks. At each time point, in vivo compliance, angiography and histological examination with morphology were performed.

    RESULTS: PCL grafts showed good mechanical properties and ease of handling. The average graft compliance was 14.5 ± 1.7%/ mmHg compared to 7.8 ± 0.9% for the abdominal position and 45.1 ± 3.2%/ mmHg for the native carotid artery. The overall patency for the carotid position was 65% as compared to 100% in the abdominal position. Complete endothelialisation was achieved at 3 weeks and cell invasion was more rapid than in the aortic position. In contrast, intimal hyperplasia (IH) and vascular density were less pronounced than in the aortic position.

    CONCLUSION: Our PCL grafts in the carotid position were well endothelialised with early cellular infiltration, higher compliance, lower IH and calcification compared to the similar grafts implanted in the aortic position. However, there was a higher occlusion rate compared to our abdominal aorta series. Anatomical position, compliance mismatch, flow conditions may answer the difference in patency seen.

    Matched MeSH terms: Polyesters/chemistry
  12. Samsudin H, Auras R, Burgess G, Dolan K, Soto-Valdez H
    Food Res Int, 2018 03;105:920-929.
    PMID: 29433289 DOI: 10.1016/j.foodres.2017.11.065
    A two-step solution based on the boundary conditions of Crank's equations for mass transfer in a film was developed. Three driving factors, the diffusion (D), partition (Kp,f) and convective mass transfer coefficients (h), govern the sorption and/or desorption kinetics of migrants from polymer films. These three parameters were simultaneously estimated. They provide in-depth insight into the physics of a migration process. The first step was used to find the combination of D, Kp,f and h that minimized the sums of squared errors (SSE) between the predicted and actual results. In step 2, an ordinary least square (OLS) estimation was performed by using the proposed analytical solution containing D, Kp,f and h. Three selected migration studies of PLA/antioxidant-based films were used to demonstrate the use of this two-step solution. Additional parameter estimation approaches such as sequential and bootstrap were also performed to acquire a better knowledge about the kinetics of migration. The proposed model successfully provided the initial guesses for D, Kp,f and h. The h value was determined without performing a specific experiment for it. By determining h together with D, under or overestimation issues pertaining to a migration process can be avoided since these two parameters are correlated.
    Matched MeSH terms: Polyesters/chemistry*
  13. Pachiyappan S, Shanmuganatham Selvanantham D, Kuppa SS, Chandrasekaran S, Samrot AV
    IET Nanobiotechnol, 2019 Jun;13(4):416-427.
    PMID: 31171747 DOI: 10.1049/iet-nbt.2018.5053
    In this study, polyhydroxybutyrate (PHB) nanoparticles were synthesised following nanoprecipitation method having different solvents and surfactant (Tween 80) concentrations. In this study, PHB nanoparticles were encapsulated with curcumin and subjected for sustained curcumin delivery. Both the curcumin loaded and unloaded PHB nanoparticles were characterised using FTIR, SEM, and AFM. Sizes of the particles were found to be between 60 and 300 nm. The drug encapsulation efficiency and in vitro drug release of the nanoparticles were analysed. Antibacterial activity and anticancer activity were also evaluated. The LC50 values of most of the nanoparticles were found to be between 10 and 20 µg/100 µl, anticancer activity of curcumin loaded PHB nanoparticles were further confirmed by AO/PI staining and mitochondrial depolarisation assay.
    Matched MeSH terms: Polyesters/chemistry
  14. Huu Phong T, Van Thuoc D, Sudesh K
    Int J Biol Macromol, 2016 Mar;84:361-6.
    PMID: 26708435 DOI: 10.1016/j.ijbiomac.2015.12.037
    A halophilic bacterium isolated from mangrove soil sample in Northern Vietnam, Yangia sp. ND199 was found capable of producing homopolymer poly(3-hydroxybutyrate) [P(3HB)], copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)], and copolymer poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] from different carbon sources. The presence of 3HB, 3HV, and 4HB monomers were confirmed by gas chromatography and nuclear magnetic resonance analysis. Only P(3HB) was produced using carbon sources such as fructose or by a combination of fructose with 1,5-pentanediol, 1,6-hexanediol, sodium hexanoate, or sodium octanoate. The biosynthesis of P(3HB-co-3HV) was achieved by adding cosubstrates such as sodium valerate and sodium heptanoate. When 1,4-butanediol, γ-butyrolactone or sodium 4-hydroxybutyrate was added to the culture medium, P(3HB-co-4HB) containing 4.0-7.1mol% 4HB fraction was accumulated. The molecular weights and thermal properties of polyesters were determined by gel permeation chromatography and differential scanning calorimeter, respectively. The results showed that Yangia sp. ND199 is able to produce polyester with high weight average molecular weight ranging from 1.3×10(6) to 2.2×10(6) Dalton and number average molecular weight ranging from 4.2×10(5) to 6.9×10(5) Dalton. The molecular weights, glass transition temperature as well as melting temperature of homopolymer P(3HB) are higher than those of copolymer P(3HB-co-3HV) or P(3HB-co-4HB).
    Matched MeSH terms: Polyesters/chemistry
  15. Jau MH, Yew SP, Toh PS, Chong AS, Chu WL, Phang SM, et al.
    Int J Biol Macromol, 2005 Aug;36(3):144-51.
    PMID: 16005060
    Three strains of Spirulina platensis isolated from different locations showed capability of synthesizing poly(3-hydroxybutyrate) [P(3HB)] under nitrogen-starved conditions with a maximum accumulation of up to 10 wt.% of the cell dry weight (CDW) under mixotrophic culture conditions. Intracellular degradation (mobilization) of P(3HB) granules by S. platensis was initiated by the restoration of nitrogen source. This mobilization process was affected by both illumination and culture pH. The mobilization of P(3HB) was better under illumination (80% degradation) than in dark conditions (40% degradation) over a period of 4 days. Alkaline conditions (pH 10-11) were optimal for both biosynthesis and mobilization of P(3HB) at which 90% of the accumulated P(3HB) was mobilized. Transmission electron microscopy (TEM) revealed that the mobilization of P(3HB) involved changes in granule quantity and morphology. The P(3HB) granules became irregular in shape and the boundary region was less defined. In contrast to bacteria, in S. platensis the intracellular mobilization of P(3HB) seems to be faster than the biosynthesis process. This is because in cyanobacteria chlorosis delays the P(3HB) accumulation process.
    Matched MeSH terms: Polyesters/chemistry*
  16. Mohamad N, Mazlan MM, Tawakkal ISMA, Talib RA, Kian LK, Fouad H, et al.
    Int J Biol Macromol, 2020 Nov 15;163:1451-1457.
    PMID: 32738328 DOI: 10.1016/j.ijbiomac.2020.07.209
    The growing global awareness for environmental protection has inspired the exploration on producing active packaging films from bio-based materials. In present work, three types of active agents were studied by incorporating thymol(T), kesum(K), and curry(C) (10% wt.) into polylactic acid (PLA) to produce PLA-10T, PLA-10K, and PLA10-C packaging films via solvent casting method. The morphology, functional chemistry, thermal stability, permeability, and antimicrobial properties were evaluated for PLA films. Functional chemical analysis confirmed the presence of interfacial bonding between aromatic groups of active agents and PLA carbonyl group. PLA-10K exhibited the highest thermal resistance comparing to PLA-10T and PLA-10C while water vapor barrier was enhanced after incorporation of active agents. Qualitative observation had indicated that chicken meat could be preserved in the active films until 15 days, while odourless and firm texture properties retained in food sample. For disc diffusion assay (in vitro), it showed positive results against Gram-positive bacteria (Staphylococcus aureus) whereas with negative results against Gram-negative bacteria (Escherichia coli) and Aspergillus Brasiliensis due to embedded active agents within PLA matrix. We concluded that produced active agents filled PLA films potential to use in food packaging application to enhance the shelf life of meats, fruits and vegetables product.
    Matched MeSH terms: Polyesters/chemistry*
  17. Samrot AV, Sean TC, Kudaiyappan T, Bisyarah U, Mirarmandi A, Faradjeva E, et al.
    Int J Biol Macromol, 2020 Dec 15;165(Pt B):3088-3105.
    PMID: 33098896 DOI: 10.1016/j.ijbiomac.2020.10.104
    Chitosan, collagen, gelatin, polylactic acid and polyhydroxyalkanoates are notable examples of biopolymers, which are essentially bio-derived polymers produced by living cells. With the right techniques, these biological macromolecules can be exploited for nanotechnological advents, including for the fabrication of nanocarriers. In the world of nanotechnology, it is highly essential (and optimal) for nanocarriers to be biocompatible, biodegradable and non-toxic for safe in vivo applications, including for drug delivery, cancer immunotherapy, tissue engineering, gene delivery, photodynamic therapy and many more. The recent advancements in understanding nanotechnology and the physicochemical properties of biopolymers allows us to modify biological macromolecules and use them in a multitude of fields, most notably for clinical and therapeutic applications. By utilizing chitosan, collagen, gelatin, polylactic acid, polyhydroxyalkanoates and various other biopolymers as synthesis ingredients, the 'optimal' properties of a nanocarrier can easily be attained. With emphasis on the aforementioned biological macromolecules, this review presents the various biopolymers utilized for nanocarrier synthesis along with their specific synthetization methods. We further discussed on the characterization techniques and related applications for the synthesized nanocarriers.
    Matched MeSH terms: Polyesters/chemistry*
  18. Wsoo MA, Razak SIA, Bohari SPM, Shahir S, Salihu R, Kadir MRA, et al.
    Int J Biol Macromol, 2021 Jun 30;181:82-98.
    PMID: 33771547 DOI: 10.1016/j.ijbiomac.2021.03.108
    Vitamin D deficiency is now a global health problem; despite several drug delivery systems for carrying vitamin D due to low bioavailability and loss bioactivity. Developing a new drug delivery system to deliver vitamin D3 is a strong incentive in the current study. Hence, an implantable drug delivery system (IDDS) was developed from the electrospun cellulose acetate (CA) and ε-polycaprolactone (PCL) nanofibrous membrane, in which the core of implants consists of vitamin D3-loaded CA nanofiber (CAVD) and enclosed in a thin layer of the PCL membrane (CAVD/PCL). CA nanofibrous mat loaded with vitamin D3 at the concentrations of 6, 12, and 20% (w/w) of vitamin D3 were produced using electrospinning. The smooth and bead-free fibers with diameters ranged from 324 to 428 nm were obtained. The fiber diameters increased with an increase in vitamin D3 content. The controlled drug release profile was observed over 30-days, which fit with the zero-order model (R2 > 0.96) in the first stage. The mechanical properties of IDDS were improved. Young's modulus and tensile strength of CAVD/PCL (dry) were161 ± 14 and 13.07 ± 2.5 MPa, respectively. CA and PCL nanofibers are non-cytotoxic based on the results of the in-vitro cytotoxicity studies. This study can further broaden in-vivo study and provide a reference for developing a new IDDS to carry vitamin D3 in the future.
    Matched MeSH terms: Polyesters/chemistry*
  19. Huong KH, Teh CH, Amirul AA
    Int J Biol Macromol, 2017 Aug;101:983-995.
    PMID: 28373050 DOI: 10.1016/j.ijbiomac.2017.03.179
    This study reports the production of P(3HB-co-4HB) [Poly(3-hydroxybutyrate-co-4-hydroxybutyrate)] in possession of high molecular weight and elastomeric properties by Cupriavidus sp. USMAA1020 in single-stage mixed-substrate cultivation system. 1,4-butanediol and 1,6-hexanediol are found to be efficient substrate mixture that has resulted in high copolymer yield, occupying a maximum of 70wt% of the total biomass and producing higher 4HB monomer composition ranging from 31mol% to 41mol%. In substrate mixtures involving 1,6-hexanediol, cleavage of the 6-hydroxyhexanoyl-CoA produces Acetyl-CoA and 4-hydroxybutyryl-CoA. Acetyl-CoA is instrumental in initiating the cell growth in the single-stage fermentation system, preventing 4-hydroxybutyryl-CoA from being utilized via β-oxidation and retained the 4HB monomer at higher ratios. Macroscopic kinetic models of the bioprocesses have revealed that the P(3HB-co-4HB) formation appears to be in the nature of mixed-growth associated with higher formation rate during exponential growth phase; evidenced by higher growth associated constants, α, from 0.0690g/g to 0.4615g/g compared to non-growth associated constants, β, from 0.0092g/g/h to 0.0459g/g/h. The P(3HB-co-31mol% 4HB) produced from the substrate mixture exhibited high weight-average molecular weight, Mwof 927kDa approaching a million Dalton, and possessed elongation at break of 1637% upon cultivation at 0.56wt% C. This is the first report on such properties for the P(3HB-co-4HB) copolymer. The copolymer is highly resistant to polymer deformation after being stretched.
    Matched MeSH terms: Polyesters/chemistry
  20. Huong KH, Elina KAR, Amirul AA
    Int J Biol Macromol, 2018 Sep;116:217-223.
    PMID: 29723627 DOI: 10.1016/j.ijbiomac.2018.04.148
    Long carbon chain alkanediols are used in the production of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)], however these substrates possess high toxicity towards bacterial cells. This study demonstrated the effective utilisation of a long carbon chain alkanediol, namely 1,8-octanediol, to enhance the yield and production of a copolymer with a high molecular weight of over 1000 kDa, which is desirable for novel applications in medical and biopharmaceuticals. The increased PHA content (47-61 wt%) and concentration (1.7-4.5 g/L) was achieved by additional feeding of a combination of C4 substrates at C/N 10, with 1,8-octanediol + γ-butyrolactone producing P(3HB-co-22 mol% 4HB) with a high molecular weight (1060 kDa) and elongation at break of 970%. The DO-stat feeding strategy of C/N 10 has shown an increment of PHA concentration for both carbon combination, 0.45-4.27 g/L and 0.32-3.36 g/L for 1,8-octanediol + sodium 4-hydroxybutyrate (4HB-Na) and 1,8-octanediol + γ-butyrolactone, but with a slight reduction on molecular weight and mechanical strength. Nonetheless, further study revealed that a nitrogen-absence feeding strategy could retain the high molecular weight and elongation at break of the copolymer, and simultaneously improving the overall P(3HB-co-4HB) production.
    Matched MeSH terms: Polyesters/chemistry*
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