Xinggang Yang

Bio: Xinggang Yang is an academic researcher from Shenyang Pharmaceutical University. The author has contributed to research in topics: Drug delivery & Controlled release. The author has an hindex of 26, co-authored 113 publications receiving 2292 citations. Previous affiliations of Xinggang Yang include Liaoning University of Traditional Chinese Medicine.

Fabrication of Carvedilol Nanosuspensions Through the Anti-Solvent Precipitation–Ultrasonication Method for the Improvement of Dissolution Rate and Oral Bioavailability

Abstract: The present study aims to prepare carvedilol (CAR) nanosuspensions using the anti-solvent precipitation-ultrasonication technique to improve its dissolution rate and oral bioavailability. Alpha-tocopherol succinate (VES) was first used as a co-stabilizer to enhance the stability of the nanosuspensions. The effects of the process parameters on particle size of the nanosuspensions were investigated. The optimal values of the precipitation temperature, power inputs, and the time length of ultrasonication were selected as 10°C, 400 W, and 15 min, respectively. Response surface methodology based on central composite design was utilized to evaluate the formulation factors that affect the size of nanosuspensions, i.e., the concentration of CAR and VES in the organic solution, and the level of sodium dodecyl sulfate in the anti-solvent phase, respectively. The optimized formulation showed a mean size of 212 ± 12 nm and a zeta potential of -42 ± 3 mV. Scanning electron microscopy revealed that the nanosuspensions were flaky-shaped. Powder X-ray diffraction and differential scanning calorimetry analysis confirmed that the nanoparticles were in the amorphous state. Fourier transform infrared analysis demonstrated that the reaction between CAR and VES is probably due to hydrogen bonding. The nanosuspension was physically stable at 25°C for 1 week, which allows it to be further processing such as drying. The dissolution rate of the nanosuspensions was markedly enhanced by reducing the size. The in vivo test demonstrated that the C(max) and AUC(0-36) values of nanosuspensions were approximately 3.3- and 2.9-fold greater than that of the commercial tablets, respectively.

Nano based drug delivery systems: recent developments and future prospects

Abstract: Nanomedicine and nano delivery systems are a relatively new but rapidly developing science where materials in the nanoscale range are employed to serve as means of diagnostic tools or to deliver therapeutic agents to specific targeted sites in a controlled manner Nanotechnology offers multiple benefits in treating chronic human diseases by site-specific, and target-oriented delivery of precise medicines Recently, there are a number of outstanding applications of the nanomedicine (chemotherapeutic agents, biological agents, immunotherapeutic agents etc) in the treatment of various diseases The current review, presents an updated summary of recent advances in the field of nanomedicines and nano based drug delivery systems through comprehensive scrutiny of the discovery and application of nanomaterials in improving both the efficacy of novel and old drugs (eg, natural products) and selective diagnosis through disease marker molecules The opportunities and challenges of nanomedicines in drug delivery from synthetic/natural sources to their clinical applications are also discussed In addition, we have included information regarding the trends and perspectives in nanomedicine area

Smart micro/nanoparticles in stimulus-responsive drug/gene delivery systems

Abstract: New achievements in the realm of nanoscience and innovative techniques of nanomedicine have moved micro/nanoparticles (MNPs) to the point of becoming actually useful for practical applications in the near future. Various differences between the extracellular and intracellular environments of cancerous and normal cells and the particular characteristics of tumors such as physicochemical properties, neovasculature, elasticity, surface electrical charge, and pH have motivated the design and fabrication of inventive “smart” MNPs for stimulus-responsive controlled drug release. These novel MNPs can be tailored to be responsive to pH variations, redox potential, enzymatic activation, thermal gradients, magnetic fields, light, and ultrasound (US), or can even be responsive to dual or multi-combinations of different stimuli. This unparalleled capability has increased their importance as site-specific controlled drug delivery systems (DDSs) and has encouraged their rapid development in recent years. An in-depth understanding of the underlying mechanisms of these DDS approaches is expected to further contribute to this groundbreaking field of nanomedicine. Smart nanocarriers in the form of MNPs that can be triggered by internal or external stimulus are summarized and discussed in the present review, including pH-sensitive peptides and polymers, redox-responsive micelles and nanogels, thermo- or magnetic-responsive nanoparticles (NPs), mechanical- or electrical-responsive MNPs, light or ultrasound-sensitive particles, and multi-responsive MNPs including dual stimuli-sensitive nanosheets of graphene. This review highlights the recent advances of smart MNPs categorized according to their activation stimulus (physical, chemical, or biological) and looks forward to future pharmaceutical applications.

Recent Perspectives in Ocular Drug Delivery

Abstract: Anatomy and physiology of the eye makes it a highly protected organ. Designing an effective therapy for ocular diseases, especially for the posterior segment, has been considered as a formidable task. Limitations of topical and intravitreal route of administration have challenged scientists to find alternative mode of administration like periocular routes. Transporter targeted drug delivery has generated a great deal of interest in the field because of its potential to overcome many barriers associated with current therapy. Application of nanotechnology has been very promising in the treatment of a gamut of diseases. In this review, we have briefly discussed several ocular drug delivery systems such as microemulsions, nanosuspensions, nanoparticles, liposomes, niosomes, dendrimers, implants, and hydrogels. Potential for ocular gene therapy has also been described in this article. In near future, a great deal of attention will be paid to develop non-invasive sustained drug release for both anterior and posterior segment eye disorders. A better understanding of nature of ocular diseases, barriers and factors affecting in vivo performance, would greatly drive the development of new delivery systems. Current momentum in the invention of new drug delivery systems hold a promise towards much improved therapies for the treatment of vision threatening disorders.