Entrapment of the Fastest Known Carbonic Anhydrase with Biomimetic Silica and Its Application for CO2 Sequestration

Capturing and storing CO2 is of prime importance. The rate of CO2 sequestration is often limited by the hydration of CO2, which can be greatly accelerated by using carbonic anhydrase (CA, EC 4.2.1.1) as a catalyst. In order to improve the stability and reusability of CA, a silica-condensing peptide (R5) was fused with the fastest known CA from Sulfurihydrogenibium azorense (SazCA) to form R5-SazCA; the fusion protein successfully performed in vitro silicification. The entrapment efficiency reached 100% and the silicified form (R5-SazCA-SP) showed a high activity recovery of 91%. The residual activity of R5-SazCA-SP was two-fold higher than that of the free form when stored at 25 °C for 35 days; R5-SazCA-SP still retained 86% of its activity after 10 cycles of reuse. Comparing with an uncatalyzed reaction, the time required for the onset of CaCO3 formation was shortened by 43% and 33% with the addition of R5-SazCA and R5-SazCA-SP, respectively. R5-SazCA-SP shows great potential as a robust and efficient biocatalyst for CO2 sequestration because of its high activity, high stability, and reusability.

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Enhanced Thermostability of a Fungal Alkaline Protease by Different Additives

Enzyme Research ◽

10.1155/2014/109303 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 9

Author(s):

Nilesh P. Nirmal ◽

R. Seeta Laxman

Keyword(s):

High Activity ◽

Ammonium Sulphate ◽

Alkaline Protease ◽

Residual Activity ◽

Fungal Strain ◽

Sugar Alcohols ◽

Peg 6000 ◽

Lower Stability ◽

The Stability ◽

Marginal Improvement

A fungal strain (Conidiobolus brefeldianus MTCC 5184) isolated from plant detritus secreted a high activity alkaline protease. Thermostability studies of the fungal alkaline protease (FAP) revealed that the protease is stable up to 50°C with 40% residual activity after one hour. Effect of various additives such as sugars, sugar alcohols, polyols, and salts, on the thermostability of FAP was evaluated. Among the additives tested, glycerol, mannitol, xylitol, sorbitol, and trehalose were found to be very effective in increasing the stability of FAP, which was found to be concentration dependent. Fivefold increase in residual activity of FAP was observed in the presence of trehalose (50%) and sorbitol (50%) at 50°C for 4 h, compared to FAP without additive. Other additives like calcium at 20 mM and 10–15% ammonium sulphate showed lower stability improvement than trehalose and sorbitol. NaCl, MgCl2, K2HPO4, and glycine were found to be poor stabilizers and showed only a marginal improvement. PEG 6000 did not show any increase in stability but was found to be slightly inhibitory.

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Controlled Release Characteristics of PLA-Pluronic-PLA Nano-Sized Vesicles In Vitro

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.785-786.493 ◽

2013 ◽

Vol 785-786 ◽

pp. 493-497

Author(s):

Yu Ping Li ◽

Li Zhen Sun ◽

Xiang Yuan Xiong ◽

Zi Ling Li ◽

Ting Kang Xing ◽

...

Keyword(s):

Controlled Release ◽

Protein Delivery ◽

Phosphate Buffer Solution ◽

Entrapment Efficiency ◽

Poly Lactic Acid ◽

Oral Insulin ◽

Buffer Solution ◽

The Mean ◽

The Stability

In the present study, controlled release characteristics of new nanosized PLA-Pluronic-PLA block copolymer vesicles comprising of amphiphilic poly (lactic acid) (PLA) and Pluronic block copolymers (PEO-PPO-PEO) have been evaluated as an oral insulin carrier. The mean size of vesicles was 78 nm for PLA-F127-PLA and 165 nm for PLA-P85-PLA copolymer. The mean insulin entrapment efficiency was 59.6% for PLA-P85-PLA and 26.4% for PLA-F127-PLA. The in vitro release characteristics of insulin from vesicles exhibited an initial burst in the range of pH 1.2-7.4 dissolution mediums. The presence of PLA-Pluronic-PLA vesicles improved the stability of insulin in the gastrointestinal fluids than that of the phosphate buffer solution (PBS) of insulin. More importantly, the released insulin from the vesicles maintained their biological activity. The results from this studies demonstrated that biodegradable PLA-Pluronic-PLA can self-assemble with insulin, form insulin-encapsulated vesicles, and is good carrier materials for oral insulin/protein delivery.

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DIACEREIN-LOADED NIOSOMES (DC-NS): A NEW TECHNIQUE TO SUSTAIN THE RELEASE OF DRUG ACTION

International Journal of Applied Pharmaceutics ◽

10.22159/ijap.2022v14i1.43353 ◽

2022 ◽

pp. 156-163

Author(s):

RASHAD M. KAOUD ◽

EMAN J. HEIKAL ◽

TAHA M. HAMMADY

Keyword(s):

Physical Stability ◽

In Vitro Release ◽

Entrapment Efficiency ◽

Stability Study ◽

Molar Ratios ◽

Tween 40 ◽

A New Technique ◽

The Stability ◽

Tween 60

Objective: The study's main goal is to develop a suitable niosomes (NS) encapsulated drug for anti-inflammatory effects such as diacerein (DC) and to evaluate the system's vesicle size (VS), entrapment efficiency (EE %), physical stability and in vitro release. Methods: Tween (40 and 60), cholesterol, and stearylamine were used in a 1:1:0.1 molar ratios as non-ionic surfactants. Thin film hydration was used to create the NS. Results: The higher EE% was observed with NS (F11) prepared from tween 60, cholesterol and 2.5 min sonication. These formulations' release patterns were Higuchi diffusion and first order. For the stability study, NS formulations were stored at temperature between 2-8 °C for 60 d retains the most drugs when compared to room and high temperature conditions. Conclusion: The findings of this study have conclusively shown that after NS encapsulation of DC, drug release is prolonged at a constant and controlled rate.

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Development and Optimization of Proniosomal Gel Containing Etodolac: In-vitro, Ex-vivo and In-vivo Evaluation

Ars Pharmaceutica (Internet) ◽

10.30827/ars.v62i3.17944 ◽

2021 ◽

Vol 62 (3) ◽

pp. 290-304

Author(s):

Moreshwar Patil ◽

Prashant Pandit ◽

Pavan Udavant ◽

Sandeep Sonawane ◽

Deepak Bhambere

Keyword(s):

Drug Release ◽

Zeta Potential ◽

Ex Vivo ◽

Entrapment Efficiency ◽

In Vivo Evaluation ◽

Vesicle Size ◽

Skin Delivery ◽

The Stability

Introduction: Etodolac is used in the treatment of acute pain and inflammation. It has low solubility because of high hydrophobicity and it is reported that upon oral administration shows gastric disturbances. This encourages the development of topical vesicular formulation. Method: In this work we used coacervation-phase separation method for the development of etodolac loaded vesicular system by using non-ionic surfactants, cholesterol and soya lecithin. Central composite design (rotatble) was used to optimize the concentrations of soy lecithin, surfactant and cholesterol. The prepared formulations were characterized by number of vesicles formed, vesicle size, zeta potential, entrapment efficiency, in-vitro permeation, ex-vivo permeation and anti-inflammatory study. Results: Etodolac was successfully entrapped in all formulations having efficiency in the range of 74.36% to 90.85%, which was more at 4 °C than room temperature. When hydrated with water; niosome in the range of 54 to 141 (per cubic mm) were spontaneously produced. The results of in-vitro diffusion study revealed that etodolac was released in the range of 71.86 to 97.16% over a period of 24 hrs. The average vesicle size of optimized formulation was found 211.9 nm with PDI of 0.5. The observed responses i.e. % encapsulation efficiency and drug release were 74.12 and 95.08 respectively. The zeta potential was -19.4mV revealed the stability of formulation which was further confirmed by no changes in drug content and drug release after stability studies. The % inhibition in paw volume was 40.52% and 43.61% for test and marketed proniosomal gel. Conclusion: Proniosomal gel formulation was stable and could enhance skin delivery of etodolac because of excellent permeation capability of vesicular system.

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Lipid Nanoparticles for Enhancing the Physicochemical Stability and Topical Skin Delivery of Orobol

Pharmaceutics ◽

10.3390/pharmaceutics12090845 ◽

2020 ◽

Vol 12 (9) ◽

pp. 845

Author(s):

Min-Hwan Kim ◽

Yae-Eun Jeon ◽

Soobeen Kang ◽

Jae-Young Lee ◽

Ki Won Lee ◽

...

Keyword(s):

Skin Irritation ◽

Entrapment Efficiency ◽

Aging Effect ◽

Lipid Nanoparticles ◽

Skin Aging ◽

Shea Butter ◽

Skin Delivery ◽

Cadaver Skin ◽

The Stability

Orobol is one of the major soy isoflavones, and has been reported to have various pharmacological activities, including an anti-skin-aging effect. However, since it has low solubility in water and physicochemical instability, the formulation of orobol for delivery into the dermal layer of the skin could be challenging. The objective of this study was to prepare lipid nanoparticles formulations of orobol to enhance its stability as well as its deposition into the skin. Formulations of orobol-loaded solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) were characterized in terms of their mean particle size, entrapment efficiency, and morphology. The nano-sized spherical NLCs formulations maintained the stability of orobol for up to 28 days. Moreover, the NLCs formulation significantly increased the in vitro deposition of orobol into both Strat-M membranes and human cadaver skin compared with the other formulations. Additionally, the NLCs formulation did not cause significant skin irritation in clinical study. These results demonstrate that a shea butter-based NLC formulation could be a promising and safe carrier system for improving the stability of orobol and enhancing its topical skin delivery.

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Use of inhibitors in physiological studies of carbonic anhydrase

AJP Renal Physiology ◽

10.1152/ajprenal.1977.232.4.f291 ◽

1977 ◽

Vol 232 (4) ◽

pp. F291-F297 ◽

Cited By ~ 10

Author(s):

T. H. Maren

Keyword(s):

Carbonic Anhydrase ◽

Large Range ◽

Residual Activity ◽

Response Curves ◽

Residual Rate ◽

Nonspecific Effects ◽

Different Levels ◽

Single Enzyme

The appropriate use of acetazolamide in examining physiological function is based on the following: 1) the dissociation constant of the drug-carbonic anhydrase complex (10(-8) M); 2) the concentration needed to eliminate the catalyzed reaction (10(-4) M can be achieved readily in tissues by giving 20 mg/kg at no toxicity; and 4) the lack of known effects on any other systems at concentrations below 10(-3) M. Several problems have been identified and are analyzed concerning the use of acetazolamide and allied drugs. Concentrations greater than 10(-3) M have been used in vitro and occasionally in vivo, generating nonspecific effects. Experiments in which the substrate (CO2) is varied over a large range have been interpreted without regard to alteration in both the catalyzed and uncatalyzed rates, leading to conclusions that acetazolamide acts on a transport system other than carbonic anhydrase, while in reality the drug is acting on carbonic anhydrase at different levels of its catalytic rate. Since calculation of the uncatalyzed hydration of CO2 or dehydration of HCO3-in tissues involves some uncertainty, these rates are generally best defined by studying the dose-response curves of inhibitors and observing the residual activity after full inhibition. The kidney is an exception, since here the residual rate also involves an entirely separate process. Inhibitors other than acetazolamide are useful in ruling out nonspecific effects, and in gaining certainty of access to cells. Compounds closely akin to the inhibitors, but lacking action upon carbonic anhydrase, are also available as controls. It is emphasized that acetazolamide and other carbonic anhydrase inhibitors, when properly used, are highly specific probes of a single enzyme that has a wide variety of physiological functions.

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Ibuprofen loaded nano-ethanolic liposomes carbopol gel system: in vitro characterization and anti-inflammatory efficacy assessment in Wistar rats

Journal of Polymer Engineering ◽

10.1515/polyeng-2016-0462 ◽

2018 ◽

Vol 38 (3) ◽

pp. 291-298 ◽

Cited By ~ 9

Author(s):

Atefeh Afshar Moghaddam ◽

Abdul Ahad ◽

Mohd. Aqil ◽

Farhan J. Ahmad ◽

Yasmin Sultana ◽

...

Keyword(s):

Transdermal Delivery ◽

Wistar Rats ◽

Entrapment Efficiency ◽

Stability Study ◽

In Vitro Characterization ◽

Rat Paw Edema ◽

Anti Inflammatory ◽

The Stability

AbstractThe objective of the present study was to develop and characterize nano-ethanolic liposomes (NEL) for transdermal delivery of ibuprofen (IBU). The NEL for transdermal delivery of IBU were prepared by thin film hydration technique and evaluated for vesicle size, shape, entrapment efficiency, transdermal flux, andin vivoanti-inflammatory activity in Wistar rats. The NEL optimized formulation (NEL-Opt) presented vesicle sizes of 32.85±1.98 nm and entrapment efficiency of 86.40±0.55% with improved transdermal flux. The presence of ethanol and flexibility of NEL could be the reasons for better permeation enhancement of IBU via rat’s skin.In vivoanti-inflammatory study of IBU-loaded NEL-Opt gel showed significant reduction (41.18%) of edema in carrageenan-induced rat paw edema as compared to conventional gel of IBU, where reduction of edema was found to be 12.50%. Our results suggest that developed NEL formulations are efficient systems for transdermal IBU delivery against inflammation. The stability study confirmed that the NEL-Opt gel formulation was considerably stable at refrigerator temperature. Our results concluded that NEL are an efficient carrier for transdermal delivery of IBU.

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Development of Epirubicin-Loaded Biocompatible Polymer PLA–PEG–PLA Nanoparticles: Synthesis, Characterization, Stability, and In Vitro Anticancerous Assessment

Polymers ◽

10.3390/polym13081212 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1212

Author(s):

Salam Massadeh ◽

Iman Almohammed ◽

Eman Barhoush ◽

Mustafa Omer ◽

Nouf Aldhawi ◽

...

Keyword(s):

Side Effects ◽

Double Emulsion ◽

Entrapment Efficiency ◽

Stability Study ◽

Synthesis Process ◽

Free Form ◽

Scanning Calorimetry ◽

Biocompatible Polymer ◽

Mcf 7

Epirubicin (EPI) is an anti-cancerous chemotherapeutic drug that is an effective epimer of doxorubicin with less cardiotoxicity. Although EPI has fewer side effects than its analog, doxorubicin, this study aims to develop EPI nanoparticles as an improved formula of the conventional treatment of EPI in its free form. Methods: In this study, EPI-loaded polymeric nanoparticles (EPI-NPs) were prepared by the double emulsion method using a biocompatible poly (lactide) poly (ethylene glycol) poly(lactide) (PLA–PEG–PLA) polymer. The physicochemical properties of the EPI-NPs were determined by dynamic light scattering (DLS), transmission electron microscopy (TEM), differential scanning calorimetry (DSC), entrapment efficiency and stability studies. The effect of EPI-NPs on cancer cells was determined by high throughput imaging and flow cytometry. Results: The synthesis process resulted in monodisperse EPI-NPs with a size of 166.93 ± 1.40 nm and an elevated encapsulation efficiency (EE) of 88.3%. In addition, TEM images revealed the spherical uniformness of EPI-NPs with no aggregation, while the cellular studies presented the effect of EPI-NPs on MCF-7 cells’ viability; after 96 h of treatment, the MCF-7 cells presented considerable apoptotic activity. The stability study showed that the EPI-NPs remained stable at room temperature at physiological pH for over 30 days. Conclusion: EPI-NPs were successfully encapsulated within a highly stable biocompatible polymer with minimal loss of the drug. The used polymer has low cytotoxicity and EPI-NPs induced apoptosis in estrogen-positive cell line, making them a promising, safe treatment for cancer with less adverse side effects.

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FORMULATION AND OPTIMIZATION OF NIFEDIPINE LOADED NANOCARRIERS

International Journal of Applied Pharmaceutics ◽

10.22159/ijap.2021v13i5.42050 ◽

2021 ◽

pp. 311-317

Author(s):

ASHWINI JADHAV ◽

BINOY VARGHESE CHERIYAN

Keyword(s):

Particle Size ◽

Zeta Potential ◽

Physical Stability ◽

Entrapment Efficiency ◽

Tween 80 ◽

Physicochemical Characteristics ◽

Good Choice ◽

The Stability

Objective: The main aim of this study to formulate a nifedipine-loaded nanocarrier for improving solubility and bioavailability. Methods: To improve the solubility of drug, nifedipine-loaded nanocarrier (lipotomes) were prepared by using the film lipid hydration technique. lipotomes were prepared by using tween 80, which is used for increasing solubility and cetyl alcohol for lipophilic environment. Drug excipients interaction determined by FTIR. lipotomes were characterized for particle size, Entrapment efficiency and zeta potential. lipotomes were optimized by using Design-Expert 12 software. Optimized formula further lyophilized by using different cyroproyectant to improve the stability and oral administration of the drug. Results: FTIR shows there was no interaction between formulation ingredients. Mean particle size, entrapment efficiency, zeta potential was determined and found to be 308.1 nm, 96.7%, 20.1mV, respectively. Surface morphology of lipotomes was observed by a scanning electron microscope (SEM). Optimized lipotomes was lyophilized with Mannitol (8% w/v) was the ideal cryoprotectant to retain the physicochemical characteristics of the OLT formulation after lyophilization. Conclusion: Nifedipine loaded nanocarrier was successfully prepared, using film hydration method. Which have good particle size, EE% and zeta potential. After lyophilization no significant changes was observed in particle size with good physical stability, so it could be a good choice for conventional drug delivery system by doing further investigation as in vitro and in vivo study

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Experimental study of the liposomal form of fenoterol after improving the method of obtaining it

Pharmacy Formulas ◽

10.17816/phf34272 ◽

2020 ◽

Vol 2 (2) ◽

pp. 30-37

Author(s):

Tatiana M. Ustinova ◽

Nikolai Vengerovich ◽

Mikhail A. Judin

Keyword(s):

Average Diameter ◽

Free Form ◽

Quantitative Composition ◽

Active Principle ◽

Liposomal Form ◽

Duration Of Action ◽

Second Stage ◽

The Stability

The effect of different concentrations of cryoprotector (sucrose) on the efficiency of fenoterol inclusion in the lipid matrix during lyophilization has been studied. It has been shown that the liposomal form with the content of cryoprotector in the internal environment of liposomes 2.5 % and in the external environment equal to 2 % provides long-term preservation of the drug in the liposome cavity. Under these conditions, it is possible to achieve a monodisperse distribution of particles with an average diameter of 4.281.62 m. The assumed quantitative composition of the cryoprotector ensures the manufacturability of the liposome production process, increases the stability of the lyophilizate structure and prevents the particles from sticking together, ensuring their uniformity. The profile of two-stage release of fenoterol from the liposomal form has been shown in vitro. The first stage of rapid release was characterized by a transition to free form within 15 minutes to 42 % of the encapsulated fenoterol. At the second stage, the active principle was released more slowly for 480 minutes. The model of bronchospasm induced by 1% histamine has shown the advantage of the liposomal form of fenoterol in comparison with its free form in the form of an aqueous solution. Intra-tracheal administration of the liposomal form of fenoterol at a dose of 17 ukg/kg provided for 360 minutes the preservation of external respiratory function at the level of initial values, despite histamine inhalation, while the duration of action of fenoterol did not exceed 120 minutes.

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