1.Foams stabilized with solid particles carrying stimuli-responsive polymer hairs.
Nakayama S1, Hamasaki S1, Ueno K1, Mochizuki M1, Yusa S2, Nakamura Y3, Fujii S1. Soft Matter. 2016 Apr 25. [Epub ahead of print]
Submicrometer-sized polystyrene (PS) particles carrying stimuli-responsive poly[2-(diethylamino)ethyl methacrylate] (PDEA) hairs with degrees of polymerization of 30, 60 and 90 were synthesized by dispersion polymerization and used as a particulate foam stabilizer. The effects of the composition of these PDEA-PS particles and foam formation conditions on foamability, foam stability and foam microstructures were extensively investigated. The hairy particles were found to work as an effective stabilizer of aqueous foams in basic media, in which the PDEA hairs are not protonated and thus the particle surfaces exhibit suitable wettability at the air-water interface. In contrast, little to no foam or unstable foams were formed in acidic aqueous media, in which the hairs are protonated and are therefore water soluble. Particles carrying longer hairs resulted in greater foamability and more highly stabilized foams that were capable of persisting for more than one month.
2.Methylphenidate HCL for the Treatment of ADHD in Children and Adolescents.
Childress AC1. Expert Opin Pharmacother. 2016 Apr 26. [Epub ahead of print]
INTRODUCTION: Since Ritalin (methylphenidate immediate-release or MPH IR) was first marketed in 1955, it has been a mainstay of treatment for Attention-Deficit/Hyperactivity Disorder (ADHD). Areas covered: The postulated mechanism of action, adverse events and efficacy of MPH are examined. MPH formulations that are currently on the market in the United States and those that will soon be available are considered. Various products are examined by comparing onset of effect and duration of action. Expert opinion: MPH has a well-known efficacy and safety profile. The development of extended-release (MPH-ER) was a significant advance in ADHD treatment. Recent products offer convenience in terms of dosing and timing of drug administration to improve symptom control, but efficacy is similar among all MPH-ER products. One formulation may be more appropriate for an individual patient, but no product offers significant advantages over all others. Since MPH is only effective in about 80% of patients, identifying factors that predict drug response is an active area of research.
3.The role of surfactants in the formulation of elastic liposomal gels containing a synthetic opioid analgesic.
Singh S1, Vardhan H1, Kotla NG2, Maddiboyina B3, Sharma D4, Webster TJ5. Int J Nanomedicine. 2016 Apr 8;11:1475-82. doi: 10.2147/IJN.S100253. eCollection 2016.
Transdermal drug delivery systems have made significant contributions to the medical community, but have yet to completely substitute oral or parenteral delivery. Recently, various strategies have been used to augment the transdermal delivery of therapeutics. Primarily, they include iontophoresis, electrophoresis, sonophoresis, chemical permeation enhancers, microneedles, and vesicular systems. Among these strategies, elastic liposomes appear promising. Elastic vesicle scaffolds have been developed and evaluated as novel topical and transdermal delivery systems, with an infrastructure consisting of hydrophobic and hydrophilic moieties together, and as a result, such scaffolds can accommodate drug molecules with a wide range of solubility. High deformability of these vesicles provides for better penetration of intact vesicles. This system is much more efficient at delivering low- and high-molecular-weight drugs to the skin in terms of quantity and depth.