Preparation and Characterization of β-glucosidase Films for Stabilization and Handling in Dry Configurations

2020 ◽  
Vol 21 (8) ◽  
pp. 741-747
Author(s):  
Liguang Zhang ◽  
Yanan Shen ◽  
Wenjing Lu ◽  
Lengqiu Guo ◽  
Min Xiang ◽  
...  

Background: Although the stability of proteins is of significance to maintain protein function for therapeutical applications, this remains a challenge. Herein, a general method of preserving protein stability and function was developed using gelatin films. Method: Enzymes immobilized onto films composed of gelatin and Ethylene Glycol (EG) were developed to study their ability to stabilize proteins. As a model functional protein, β-glucosidase was selected. The tensile properties, microstructure, and crystallization behavior of the gelatin films were assessed. Result: Our results indicated that film configurations can preserve the activity of β-glucosidase under rigorous conditions (75% relative humidity and 37°C for 47 days). In both control films and films containing 1.8 % β-glucosidase, tensile strength increased with increased EG content, whilst the elongation at break increased initially, then decreased over time. The presence of β-glucosidase had a negligible influence on tensile strength and elongation at break. Scanning electron-microscopy (SEM) revealed that with increasing EG content or decreasing enzyme concentrations, a denser microstructure was observed. Conclusion: In conclusion, the dry film is a promising candidate to maintain protein stabilization and handling. The configuration is convenient and cheap, and thus applicable to protein storage and transportation processes in the future.

2010 ◽  
Vol 123-125 ◽  
pp. 347-350 ◽  
Author(s):  
Mubarak A. Khan ◽  
Nazia Rahman ◽  
M. Rahman

Gelatin-PVA blend films of different compositions (0%, 5%, 10%, 15% of PVA) were prepared by casting. The tensile strength (TS) and elongation at break (Eb) of the films were studied. The TS and Eb of pure gelatin films were found to be 32 MPa and 3.3% respectively. The films were irradiated under different gamma radiation dose (50 Krad, 100 Krad, 150 Krad, 250 Krad, 500 Krad). 5% PVA containing gelatin films irradiated under 100 Krad gamma radiation showed highest TS of 42 MPa and highest Eb of 4.2%. Thermal property of the films was studied by Thermomechanical analysis (TMA) and Thermogravimetric Analysis (TGA). The grafting of PVA onto gelatin is studied by IR. In order to study surface morphology SEM study was undertaken.


2021 ◽  
Vol 22 (5) ◽  
pp. 2501
Author(s):  
Sonja Hinz ◽  
Dominik Jung ◽  
Dorota Hauert ◽  
Hagen S. Bachmann

Geranylgeranyltransferase type-I (GGTase-I) represents an important drug target since it contributes to the function of many proteins that are involved in tumor development and metastasis. This led to the development of GGTase-I inhibitors as anti-cancer drugs blocking the protein function and membrane association of e.g., Rap subfamilies that are involved in cell differentiation and cell growth. In the present study, we developed a new NanoBiT assay to monitor the interaction of human GGTase-I and its substrate Rap1B. Different Rap1B prenylation-deficient mutants (C181G, C181S, and ΔCQLL) were designed and investigated for their interaction with GGTase-I. While the Rap1B mutants C181G and C181S still exhibited interaction with human GGTase-I, mutant ΔCQLL, lacking the entire CAAX motif (defined by a cysteine residue, two aliphatic residues, and the C-terminal residue), showed reduced interaction. Moreover, a specific, peptidomimetic and competitive CAAX inhibitor was able to block the interaction of Rap1B with GGTase-I. Furthermore, activation of both Gαs-coupled human adenosine receptors, A2A (A2AAR) and A2B (A2BAR), increased the interaction between GGTase-I and Rap1B, probably representing a way to modulate prenylation and function of Rap1B. Thus, A2AAR and A2BAR antagonists might be promising candidates for therapeutic intervention for different types of cancer that overexpress Rap1B. Finally, the NanoBiT assay provides a tool to investigate the pharmacology of GGTase-I inhibitors.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Yongfang Qian ◽  
Zhen Zhang ◽  
Laijiu Zheng ◽  
Ruoyuan Song ◽  
Yuping Zhao

Design and fabrication of nanofibrous scaffolds should mimic the native extracellular matrix. This study is aimed at investigating electrospinning of polycaprolactone (PCL) blended with chitosan-gelatin complex. The morphologies were observed from scanning electron microscope. As-spun blended mats had thinner fibers than pure PCL. X-ray diffraction was used to analyze the degree of crystallinity. The intensity at two peaks at 2θof 21° and 23.5° gradually decreased with the percentage of chitosan-gelatin complex increasing. Moreover, incorporation of the complex could obviously improve the hydrophilicity of as-spun blended mats. Mechanical properties of as-spun nanofibrous mats were also tested. The elongation at break of fibrous mats increased with the PCL content increasing and the ultimate tensile strength varied with different weight ratios. The as-spun mats had higher tensile strength when the weight ratio of PCL to CS-Gel was 75/25 compared to pure PCL. Both as-spun PCL scaffolds and PCL/CS-Gel scaffolds supported the proliferation of porcine iliac endothelial cells, and PCL/CS-Gel had better cell viability than pure PCL. Therefore, electrospun PCL/Chitosan-gelatin nanofibrous mats with weight ratio of 75/25 have better hydrophilicity mechanical properties, and cell proliferation and thus would be a promising candidate for tissue engineering scaffolds.


2021 ◽  
Vol 23 (1) ◽  
pp. 16
Author(s):  
Vienna Saraswaty ◽  
Rossy Choerun Nissa ◽  
Bonita Firdiana ◽  
Akbar Hanif Dawam Abdullah

THE PHYSICOCHEMICAL CHARACTERISTICS OF RECYCLED-PLASTIC PELLETS OBTAINED FROM DISPOSABLE FACE MASK WASTES. The government policy to wear a face mask during the COVID-19 pandemic has increased disposable face mask wastes. Thus, to reduce such wastes, it is necessary to evaluate the physicochemical characteristics of disposable face masks wastes before the recycling process and the recycled products. In this study, physicochemical characterization of the 3-ply disposable face masks and the recycled plastic pellets after disinfection using 0.5% v/v sodium hypochlorite were evaluated. A set of parameters including the characterization of surface morphology by a scanning electron microscope (SEM), functional groups properties by a fourier transform infra-red spectroscopy (FT-IR), thermal behavior by a differential scanning calorimetry (DSC), tensile strength and elongation at break were evaluated. The surface morphological of each layer 3-ply disposable face mask showed that the layers were composed of non-woven fibers. The FT-IR evaluation revealed that 3-ply disposable face mask was made from a polypropylene. At the same time, the DSC analysis found that the polypropylene was in the form of homopolymer. The SEM analysis showed that the recycled plastic pellets showed a rough and uneven surface. The FT-IR, tensile strength and elongation at break of the recycled plastic pellets showed similarity with a virgin PP type CP442XP and a recycled PP from secondary recycling PP (COPLAST COMPANY). In summary, recycling 3-ply disposable face mask wastes to become plastic pellets is recommended for handling disposable face mask wastes problem.


2019 ◽  
Vol 35 (1) ◽  
pp. 221-227
Author(s):  
Maulida Lubis ◽  
Mara Bangun Harahap ◽  
Iriany Iriany ◽  
Muhammad Hendra S. Ginting ◽  
Iqbal Navissyah Lazuardi ◽  
...  

Cooking oil waste that has been disposed could contamine the environment. However, if it is processed well, it can potentially become a raw material of polyurethane. The aim of this study was to determine the best polyurethane on the tensile strength, impact strength, elongation at break, water absorption, characterization of Fourier Transform Infra-Red (FTIR) and the characterization of Scanning Electron Microscopy (SEM). The variables used in this study were ambient process temperature with 440 rpm stirring speed, 1-minute stirring time, the ratio of polyoland WCO was 7:3 (% w/w), and the ratio of Toluene Diisocyanate (TDI) and WCO was 1:1; 1:2; 1:3; 1:4 (% w/w). The results obtained from the analysis of the best tensile strength against the polyurethane synthetic was in the 1:1 ratio of mixed variations between oil and TDI with a value of 0.403 MPa. The best impact strength was in the ratio of mixed variations between oil and TDI with 1:4 (% w/w) with a value of 600.975 J/m2. The best elongation at break against polyurethane foam synthetic was in the 1:3 ratio of mixture variations of oil and TDI with a value of 4.506%.


2017 ◽  
Vol 26 (5) ◽  
pp. 096369351702600 ◽  
Author(s):  
Wenjing Xia ◽  
Nianqing Zhu ◽  
Zhongbin Ni ◽  
Mingqing Chen

Biodegradable composites from poly (butylene succinate-co-butylene adipate) (PBSA) and Taihu Lake (Wuxi, China) blue algae were prepared by melt blending. The property and structure of biocomposites were investigated. By adding extra amount of water to blue algae, the formulated blue algae acted as a plastic in the composites during blending, and exhibited a reinforcing effect on the PBSA matrix. With increasing blue algae content, the thermal stability of the composites decreased; the tensile strength at break and elongation at break of the composites reduced, but the Young's modulus of the composites increased. However, the composite with 30% blue algae loading still exhibited good mechanical performance (tensile strength at break of 21.3 MPa, elongation at break of 180%). The fabrication of value-added PBSA/algae composites appeared as an effective approach to reduce the secondary environmental pollution of Taihu blue algae.


2017 ◽  
Vol 751 ◽  
pp. 230-235 ◽  
Author(s):  
Suchipha Wannaphatchaiyong ◽  
Prapaporn Boonme ◽  
Wiwat Pichayakorn

This study aimed to develop gelatin (GEL) and gelatin/Alpha starch (GEL/αSt) dissolving films as drug delivery by casting method. Because these films were brittle and lack of elasticity, therefore, glycerin (GLY), propylene glycol (PG) or polyethylene glycol 400 (PEG) in various amounts (5-30 part per hundred of gelatin; phg) was used as plasticizer. It was found that all types and amounts of plasticizer could be blended into gelatin solution and the transparent GEL films were formed, except the GEL/PEG films presented in opaque characteristics. However, 30 phg GLY blended film was too softy. Increasing amount of plasticizer caused a decrease in tensile strength and increase in elongation at break (EAB) of films. These GEL films swelled, dissolved and eroded in 2 hours. The αSt was also blended, and the effects of αSt amounts (5-30 phg) and plasticizer types (at 25 phg) on GEL film properties were studied. The αSt dispersions mixed well in gelatin solution and gave homogenous films. The swelling and erosion of GEL/αSt films in water were faster than those of GEL films. Increasing αSt amount prolonged the swelling time and decreased the degradation rate of GEL/αSt films. The tensile strength of GEL/αSt/GLY films slightly increased when the αSt amount increased but those of PEG and PG blended films were not different. The EAB of all plasticizer blended films decreased when the amount of αSt increased. Either lidociane or lidociane hydrochloride was mixed in GEL/αSt/GLY dissolving films to use as local anesthetic. The morphology, Fourier Transform Infrared Spectroscopy confirmed their compatibilities in these films, but Differential Scanning Calorimeter showed some changes that should be further evaluated.


2020 ◽  
Vol 2 (1) ◽  
pp. 34-41
Author(s):  
Syahrul Humaidi

This study investigated the characteristics of a conductive plastic based on root starch and CuSO4 filler. The mixture variation was (95:5)%; (90:10)%; (85:15)%; (80:20)% and (75:25)%. Glycerol is used to change the material as desired (plasticizer) which is called a plasticizer. The method used in the manufacture of this material is melt intercalation. Mechanical testing includes tensile strength (tensile strength) and elongation at break. Thermal testing was done using DTA (Differential Thermal Analysis) and material conductivity testing. The characterization results showed that the optimum starch composition: CuSO4 (75:25)% had a conductivity value of 7.3 x 10-2S.m-1, a thermal test value of 410ºC. The optimum tensile strength value occurs in the composition (80:20)% with a value of 4.606 MPa


2020 ◽  
Vol 74 (9) ◽  
pp. 704-709
Author(s):  
Michael A. Nash

Protein sequences inhabit a discrete set in macromolecular space with incredible capacity to treat human disease. Despite our ability to program and manipulate protein sequences, the vast majority of protein development efforts are still done heuristically without a unified set of guiding principles. This article highlights work in understanding biophysical stability and function of proteins, developing new biophysical measurement tools and building high-throughput screening platforms to explore functional protein sequences. We highlight two primary areas. First, molecular biomechanics is a subfield concerned with the response of proteins to mechanical forces, and how we can leverage mechanical force to control protein function. The second subfield investigates the use of polymers and hydrogels in protein engineering and directed evolution in pursuit of new molecular systems with therapeutic applications. These two subdisciplines complement each other by shedding light onto sequence and structural features that can be used to impart stability into therapeutic proteins.


2011 ◽  
Vol 284-286 ◽  
pp. 459-463 ◽  
Author(s):  
Yuan Yuan Qi ◽  
Bin Liu ◽  
Xing Bin Yan

Nanofibrous scaffolds of PVA and HA were prepared by electrospinning. SEM showed the scaffolds had porous nanofibrous morphology, and the diameter of the fibers was in the range of 200-1000 nm. FTIR and XRD showed the presence of HA in the scaffolds. The mechanical properties of the scaffolds changed by the adding content of HA. For the nanoscaffolds with 2wt % HA, the ultimate tensile strength and the elongation at break was 7.5 MPa and 17%. The PVA/HA nanoscaffolds prepared by electrospinning indicated good properties, and had a potential applications in bone tissue engineering and drug delivery systems.


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