Search

The collaborative endeavor in tissue engineering is to fabricate a bio-mimetic extracellular matrix to assist tissue regeneration. Thus, a novel injectable tissue scaffold was fabricated by exploring nanotailored hyaluronic acid (nHA) and methylcellulose (MC) (nHAMC) along with pristine HA based MC scaffold (HAMC). nHA with particle size ∼22 ± 5.3 nm were obtained and nHAMC displayed a honeycomb-like 3D microporous architecture. Nano-HA bestowed better gel strength, physico-rheological and biological properties than HA. It creditably reduced the high content of salt to reduce the gelation temperature of MC. The properties ameliorated with increased in-corporation of nano-HA. The addition of salt showed more prominent effect on gelation temperature of nHAMC than in HAMC; and salting-out effect was dependent on nHA/HA content. Biocompatible nHAMC assisted adequate cell adherence and proliferation with more extended protrusions with better migration rate than control. Thus, biomodulatory effect of nanotailored glycosaminoglycan could be asserted to design an efficient thermo-responsive scaffold., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Non-toxic nanocomposites based bio-films obtained from methylcellulose (MC) can reduce environmental problems associated with synthetic polymers. A new facile route for the isolation of cellulose nano-crystals (CNC) from jute waste is successfully utilized here. The fabrication of CNC reinforced MC nanocomposites by film casting technique and the studies of the effect of CNC on the properties of the MC based nanocomposites have been reported. The synthesized nanocomposites have shown improved UV resistance, mechanical, barrier, and thermal properties. FTIR results established the physicochemical compatibility between the drug, MC and CNC in nanocomposites. In vitro permeation studies performed by using Franz diffusion cell revealed diffusion mediated sustained drug release from the devices due to the presence of interaction between MC and CNC through H-bonding, electrostatic interaction between the hydrophilic polymer/CNC chains with the drug and the formation of tortuous path. The nanocomposites can be used for edible packaging and transdermal drug delivery., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

In recent times, biosynthetic approaches toward the synthesis of nanoparticles have been shown to have several advantages over physical and chemical methods. Here, we report the extracellular mycosynthesis of γ-Fe 2 O 3 nanoparticles by Alternaria alternata. The fungal biomass when exposed to aqueous iron(III) chloride solution led to the formation of highly stable γ-Fe 2 O 3 nanoparticles extracellularly. The influence of these biosynthesized γ-Fe 2 O 3 nanoparticles on the properties of hydroxyl propyl methyl cellulose was also investigated. Characterization of the biosynthesized γ-Fe 2 O 3 nanoparticles and HPMC-γ-Fe 2 O 3 nanocomposite films were done by the different types of spectral and electron microscopic analysis. The size of the γ-Fe 2 O 3 nanoparticles ranges from 75 to 650 nm. The mechanical effect of the agglomerated γ-Fe 2 O 3 nanoparticles into the HPMC polymer matrix was also investigated.

Films based on methylcellulose (MC) and pectin (PEC) of different ratios were prepared. MC/PEC (90:10) (MP10) gave the best results in terms of mechanical properties. Sodium montmorillonite (MMT) (1, 3 and 5 wt%) was incorporated in the MP10 matrix. The resulting films were characterized by X-ray diffraction and transmission electron microscopy, and it was found that nanocomposites were intercalated in nature. Mechanical studies established that addition of 3 wt% MMT gave best results in terms of mechanical properties. However, thermo-gravimetric and dynamic mechanical analysis proved that decomposition and glass transition temperature increased with increasing MMT concentration from 1 to 5 wt%. It was also observed that moisture absorption and water vapor permeability studies gave best result in the case of 3 wt% MMT. Optical clarity of the nanocomposite films was not much affected with loading of MMT. In vitro drug release studies showed that MC/PEC/MMT based films can be used for controlled transdermal drug delivery applications., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The effect of weight average molecular weight (Mw) of methyl cellulose (MC) on the gelation behavior of Poloxamer 407 (PM) and in vitro release of Ketorolac Tromethamine (KT) from different ophthalmic formulations based on PM is examined. A drop of gelation temperature of PM is observed using MC of various M(w) by test tube tilting method, UV-vis spectroscopy, viscometry and rheometry. It is also observed that the viscosity and gel strength of all the formulations are increased with the increase in Mw of MC. PM with highest Mw of MC provides best drug release property among all the formulations. It is evident from this investigation that there is a distinct effect of M(w) of MC on the gelation behavior of PM as well as on the drug release profile of KT from PM-MC based ophthalmic formulations., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Nickel nanoparticles synthesized from NiCl2·6H2O by hydrazine hydrate in mixed solvent of ethanol and water in the presence of hydroxypropylmethylcellulose (HPMC) as protective and stabilizing agents. The morphology and sizes of synthesized Ni nanoparticles were studied by field-emission-scanning-electron microscopy (FESEM). Structural properties of nanoparticles were examined by X-ray diffraction (XRD). The polymer stabilized Ni nanoparticles were characterized by Fourier-transform infrared (FTIR) spectroscopy. The magnetic measurement showed that the resultant Ni nanoparticles were ferromagnetic. Also, the saturation magnetization (MS), remanent magnetization (MR) and coercivity (MR) were observed to increase with decreasing temperature. The results of magnetic characterization showed that the magnetic properties of the HPMC stabilized Ni nanoparticles are quite different from those of the bared Ni nanoparticles. All the observed magnetic properties essentially reflected the very typical nanoparticle type nature. Consequently, the resulting Ni nanoparticles were found to be highly active and recyclable catalyst for Suzuki coupling reactions., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Hydroxypropylmethylcellulose (HPMC)/montmorillonite (MMT) nanocomposite films are prepared by solution intercalation method. Mechanical, thermal, moisture absorption, optical clarity and water vapor permeability of HPMC/MMT nanocomposite films are measured. X-ray diffraction (XRD) and transmission electron microscopic (TEM) results establish formation of partially intercalated and partially exfoliated HPMC/MMT nanocomposite films. In presence of MMT, the tensile strength, tensile modulus and elongation at break of HPMC films are improved. The thermal stability of HPMC/MMT nanocomposites is better than pure HPMC. The moisture absorption of HPMC film measured in 75% of constant relative humidity is reduced with loading of MMT. Optical clarity of HPMC film is almost unaffected in presence of MMT. Water vapor permeability of HPMC decreases in presence of nanoclay due to increasing tortuous path for diffusion., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Gelation temperature of MC was reduced from 59°C to 54°C with the addition of 10% PEG. Sodium tartrate (NaT) and sodium citrate (NaC) were added to the MC-PEG solution to further reduce the gelation temperature close to physiological temperature. Different techniques were used to measure the gelation temperature of all formulations. It was observed that NaC was more effective in reducing the gelation temperature of MC-PEG combination than NaT. Environmental scanning electron microscopy (ESEM) images of hydrogels containing NaC and NaT showed that NaC containing hydrogel having an interconnected microporous structure instead of the hollow rod like structure as in the case of NaT containing hydrogel. In vitro drug release studies showed that drug release time increased from 6 to 9h by only changing the type of salt from NaT to NaC in MC-PEG combination., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Gelation temperature of methylcellulose (MC) can be altered by adding different additives. Pure MC showed sol-gel transition at 60°C. Sodium citrate and sodium tartrate were used alone and in combination to see the effect of individual salt and combination of salts on the gelation temperature of MC. The gelation temperature of all the binary and ternary combinations of MC and salts were measured with different methods such as test tube tilting method (TTM), UV-vis spectroscopy, viscometry, and by rheometer and also the morphology of gels were characterized with the help of environmental scanning electron microscopy (ESEM). It was observed that when 0.1 M sodium citrate (NaC) and 0.1 M sodium tartrate (NaT) were used separately, the gelation temperature of MC was reduced up to 44°C and 47°C respectively but when mixture of NaC and NaT (0.1 (M) NaC and 0.1 (M) (NaT)) were used the gelation temperature was further reduced to 36°C. It was clear from ESEM images that when NaC and NaT were used separately the formation of network was not distinguishable. But, well-connected network structure was observed when a mixture 0.1 M NaC and 0.1 M NaT was used., (Copyright © 2012 Elsevier B.V. All rights reserved.)

In this paper we reported preparation of methylcellulose-silver nanocomposite films by mixing of aqueous solution of methylcellulose with silver nitrate followed by casting. The silver nanoparticles were generated in methylcellulose matrix through reduction and stabilization by methylcellulose. The surface plasmon band at 412 nm indicated the formation of Ag nanoparticles. The MC-Ag nanocomposite films were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infrared (FTIR). The X-ray diffraction analysis of synthesized MC-Ag nanocomposite films revealed that metallic silver was present in face centered cubic crystal structure. Average crystallite size of silver nanocrystal was 22.7 nm. The FTIR peaks of as-synthesized MC-Ag nanocomposite fully designated the strong interaction between Ag nanoparticles and MC matrix. Nano-sized silver modified methylcellulose showed enhanced mechanical properties i.e. the introduction of Ag leading to both strengthening and toughening of MC matrix. The methylcellulose-silver nanocomposite films offered excellent antimicrobial activity against various microorganisms., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The effect of molecular weight of poly(vinyl alcohol) (PVA) and sodium chloride on the gelation temperature of methylcellulose (MC) was studied with the objective to develop a MC based formulation for sustained delivery of ketorolac tromethamine a model ophthalmic drug. Pure MC showed sol-gel transition at 61.2 °C. In order to reduce the gelation temperature of MC and to increase the drug release time, PVA was used. Different techniques such as test tube tilting method, UV-vis spectroscopy, viscometry and rheometry were used to measure gelation temperature of all the binary combinations of MC and PVA. It was observed that the gelation temperature of MC was reduced with the addition of 4% PVA and also the extent of reduction of the gelation temperature of MC was dependent on the molecular weight of PVA. The strong interactions between MC and PVA molecules were established using Fourier transform infrared spectroscopy. To study the in vitro drug release properties of the MC-PVA binary combinations, 6% sodium chloride was used to reduce the gelation temperature further up to physiological temperature. It was observed that the drug release time increased from 5 to 8h with the increase of molecular weight of PVA from 9×10(3) to 1.3×10(5) and this was due to the higher viscosity, better gel strength and greater interactions between the drug and PVA molecules in case of PVA (1.3×10(5)) compared to PVA (9×10(3)). In order to have an idea about the nature of interactions between the functional moieties of the drug and the polymer unit of PVA, a theoretical study was carried out., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Graphene has intriguing electrical, mechanical, thermal and biological properties that are being investigated for use in composites, modern electronics, membranes, and in the industry. Also, graphene has huge biological applications. Hydroxypropyl methylcellulose (HPMC) is a widely used bio-polymer effective for various biomedical applications. As a filler in this polymer matrix, graphene oxide (GO), reduced graphene oxide (RGO) and silver (Ag) nanoparticles (NPs) can be used to improve various properties of the matrix. They are also beneficial for bio-applications like drug delivery, the production of reactive oxygen species (ROS) and the antimicrobial properties of nanocomposite films. Here we synthesize a series of polymer nanocomposites taking GO, RGO and Ag NPs as a filler by the solution mixing method and explore the comparative biological application of such composites. We choose Ag NPs as it has the superior potential for multiple drug resistance. X-ray diffraction, Fourier-transform infrared and scanning electron microscope studies are used to describe how nanocomposites are formed. Energy-dispersive X-ray and dynamic mechanical analyzer analyses were also done to check elemental percentage in nanocomposite films and mechanical properties, respectively. To check several fruitful applications, antimicrobial properties, ROS generation and in-vitro drug release study of nanocomposite films with the loading of Ketorolac Tromethamine were also performed. [ABSTRACT FROM AUTHOR]

The poor bioavailability and therapeutic response exhibited by conventional ophthalmic solutions may be overcome by the use of thermo-reversible in situ gel. The purpose of this study was to examine the influence of different salts on the gelation, rheology and drug release of in situ gel based on methylcellulose. The gel temperature of 1% w/v methylcellulose (MC) was 60°°C. It was found that 5--7% w/v sodium chloride (NaCl), 8--9% w/v potassium chloride (KCl), or 5% w/v sodium bicarbonate (NaHCO3) was capable of decreasing the gel temperature below physiological temperature, i.e. 37°°C. Rheological studies indicated a large increase in viscosity at 37°°C with the addition of salts in MC solutions. The duration of drug release from MC solution was 1.5 h. The significant observation was that the duration of drug release increased from 1.5 h to 3--5 h from salted MC solutions depending on the concentration and the type of salt. So, it can be concluded that the salted MC solutions were a better alternative than the MC solution to enhance the ocular bioavailability of the drug. [ABSTRACT FROM AUTHOR]

Over the past few years, there is a drive toward the fabrication and application of bio-based non-cytotoxic drug carriers. Cellulose nanocrystals (CNCs) have gotten immense research attention as a promising bioderived material in the biomedical field due to its remarkable properties. The delivery of analgesic and anti-inflammatory drug, ketorolac tromethamine (KT) by transdermal route is stipulated herewith to fabricate suitable transdermal therapeutic systems. We have synthesized CNCs from jute fibers and aim to develop a non-cytotoxic polymer-based bionanocomposites (BNCs) transdermal patch, formulated with methylcellulose (MC), chitosan (CH), along with exploration of CNCs for sustained delivery of KT, where CNCs act as nanofiller and elegant nanocarrier. CNCs reinforced MCCH blends were prepared via the solvent evaporation technique. The chemical structure, morphology, and thermal stability of the prepared bionanocomposites formulations were studied by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), TGA, DSC, DMA, and SEM. The In vitro drug release studies were executed using Franz diffusion cells. The BNC patches showed in-vitro cytocompatibility and the drug release study revealed that BNC containing 1 wt% CNCs presented the best-sustained drug release profile. The bioderived CNCs appear to enhance the BNCs drug's bioavailability, which could have a broad prospect for TDD applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The aim of the present study was the development of thermo-sensitive in-situ gels for in-vitro evaluation of ophthalmic delivery systems of ketorolac tromethamine (KT), based on methylcellulose (MC) in combination with hydroxypropylmethyl cellulose (HPMC). The gel temperature of 1% MC solutionwas observed at 60°C. It was found that 6% oral rehydration salt without dextrose (ORS) was capable to reduce the gel temperature below physiological temperature. HPMC was added to increase viscosity and drug release time. The results indicated a large increase in viscosity at 37°C with addition of HPMC whch provided sustained release of the drug over a 4h period. From in-vitro release studies, it could be concluded that the developed systems were thus a better alternative to conventional eye drops. [ABSTRACT FROM AUTHOR]

Evaluation of the potential for oral sustained drug delivery of formulations with in - situ gelling properties is the main objective of the present investigation. Oral administration of aqueous dispersion of sodium alginate (1.5% w/v) containing calcium ions in complex form resulted in the formation of gel matrix as a consequence of the release of the calcium ions in the acidic environment of stomach fluid. Addition of methylcellulose, sodium chloride and polyethylene glycol improved the drug retention efficacy of the gel. In this investigation, the study on the influence of added excipients on the rheological and drug release properties of the formulations has been focused. In - vitro studies demonstrated diffusion-controlled release of paracetamol from the gels. The bioavailability of orally administered paracetamol from the in - situ gel F4 (composed of 1.5% sodium alginate, 1.5% methyl cellulose, 3% CaCO 3 , 2% NaCl 0.05% polyethylene glycol) administered in the stomach of rabbit, was more sustained as compared to the commercially available suspension Calpol® containing an identical dose of paracetamol. [ABSTRACT FROM AUTHOR]

Highlights: [•] Formation of GO is confirmed by XRD, FTIR and Raman spectral analysis. [•] HPMC/GO nanocomposites are developed. [•] XRD and SEM establish the formation of exfoliated HPMC/GO nanocomposites. [•] Enhancements in mechanical and thermal properties of nanocomposites are observed. [•] Moisture absorption and WVTR of HPMC film are declined with GO loading. [ABSTRACT FROM AUTHOR]