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Study of carbon nanotubes’ embedment into porous polymeric membranes for wastewater treatment
Published in Alberto Figoli, Jan Hoinkis, Sacide Alsoy Altinkaya, Jochen Bundschuh, Application of Nanotechnology in Membranes for Water Treatment, 2017
John A. Anastasopoulos, Amaia Soto Beobide, Theodoros Karachalios, Katerina Kouravelou, George A. Voyiatzis
In addition, surfactants were used to functionalize CNTs. The physical adsorption of surfactant on the CNT-surface lowers the surface tension of CNTs that effectively prevents their aggregation. Furthermore, the surfactant-treated CNTs overcome the van der Waals attraction by electrostatic/steric repulsive forces. Sodium dodecyl sulfate (SDS) is an anionic surfactant with the formula CH3(CH2)11OSO3Na. It consists of a 12-carbon tail attached to a sulfate group giving it amphiphilic properties and was extensively used for the dispersion of CNTs in the ratio 1:1 (SDS:Thin-MW/MW-CNTs) or 1.5:1 (SDS:SW-CNTs), in the aqueous media prepared. Another surfactant employed was the poloxamer 407, which is a non-ionic surfactant. It is a triblock copolymer consisting of a central hydrophobic block of polypropylene glycol (propylene glycol block: 56 repeat units) flanked by two hydrophilic blocks of polyethylene glycol (total PEG blocks: 101 repeat units). Poloxamer 407:CNTs ratio was the same as the SDS:CNTs.
Application of Bioresponsive Polymers in Drug Delivery
Published in Deepa H. Patel, Bioresponsive Polymers, 2020
Manisha Lalan, Deepti Jani, Pratiksha Trivedi, Deepa H. Patel
A thermoresponsive gel of Pluronic F127 was investigated for transdermal delivery indomethacin. Similarly, poloxamer 407 gel was investigated for insulin delivery. The drug delivery from smart polymers could be augmented with the use of supportive technologies like iontophoresis and use of chemical permeation enhancers [11].
Polymeric Biomaterials in Pulmonary Drug Delivery
Published in Severian Dumitriu, Valentin Popa, Polymeric Biomaterials, 2020
Nicole A. Beinborn, Robert O. Williams
Polymeric surfactants have also been studied as stabilizing agents for dry powder formulations. Poloxamer 188 was used at a concentration of 2% w/w to stabilize dry powders for inhalation composed of thymopentin, mannitol, and leucine. The authors also found that inclusion of poloxamer 188 improved the flowability of the dry powders (Wang et al. 2009). Other researchers incorporated polysorbate 20, polysorbate 80, and poloxamer 407 into compositions containing itraconazole produced by evaporative precipitation into aqueous solution and spray freezing into liquid. The resulting amorphous nanoparticulate formulations were dispersed in normal saline and nebulized to mice in a whole-body inhalation chamber (McConville et al. 2006; Vaughn et al. 2006). Similarly, Tam et al. utilized polysorbate 80 to stabilize a cyclosporine A formulation prepared by controlled antisol-vent precipitation into aqueous solution. The stabilized nanoparticulate dispersion was aerosolized to mice using a nose-only inhalation chamber, resulting in high lung levels of cyclosporine A (Tam et al. 2008). In another study, the addition of polysorbate 20 to solutions of recombinant human growth hormone decreased aggregation during spray drying but negatively affected the fine particle fraction of the dry powders (Jalalipour et al. 2008a). Singh et al. coated fluticasone propionate with poloxamer using a spray drying method to form microparticles suitable for pulmonary delivery when blended with carrier lactose. Following nose-only aerosolization to rabbits, the microparticles remained in the lungs for approximately 12 h (Singh et al. 2007).
Potentiating the solubility of BCS class II drug zaltoprofen using nanodispersion technology
Published in Journal of Dispersion Science and Technology, 2023
Selvakumar Muruganantham, Venkateshwaran Krishnaswami, Ruckmani Kandasamy, Shanmugarathinam Alagarsamy
Poloxamer-407 (P-407) is an amphiphilic, poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO100-PPO65-PEO100) triblock copolymer (Figure 1b). The poly (ethylene oxide) and poly(propylene oxide) block of Poloxamer-407 is hydrophilic and hydrophobic, respectively. It is also known as Pluronic F127, and it formed a gel in around 20% w/w aqueous solution. Furthermore, in the mixture of aqueous and nonaqueous polar solvents, this triblock copolymer self-assembles. The self-assembled feature of P-407 has created a considerable interest for its usage in the drug delivery system.[23,24] Its structural versatility of P-407 facilitates to be used in pharmaceutical formulations for solubilizing, emulsifying, and dispersing activities. P-407 also serves as a stabilizing agent, helps to prevent aggregation of particles and facilitates the development of stable nanodispersions. Poloxamer micelles have been reported to boost the stability and solubility of drugs with low molecular weight, thereby improves both pharmacokinetics and biodistribution. Used in pharmaceutical formulations, P-407 contains 70% of polyoxyethylene is accountable for its hydrophilicity. In aqueous system, P-407 possesses reversible thermal properties. Moreover, by formulating nanodispersion, the P-407 may enhance the dissolution of drug due to hydroxyl groups in its structure by precipitation inhibitors mechanisms (poloxamer folder).[25–29] A recent study have been reported that for development of nanomicelles using 8% of PVP K90 with 4% of poloxamer 407 demonstrated enhanced drug release 96.0–99.0% within 8 h compared to pure drug suspension.[30] A recent study has been reported that PVP K30 and P-407 based novel anti-inflammatory drug MT-102 loaded solid dispersion revealed a 9.86-fold increased dissolution over pure MT-102.[31]