The treatment of neuropathic pain (NPP) is considered challenging, while the search for alternative medication is striving. NPP pathology is related with the expression of both the purinergic 2X7 (P2X7) receptor and the transient receptor potential vanilloid 1 receptor (TRPV1). Bufalin is a traditional Chinese medication derived from toad venom with pronounced antitumor, analgesic, and anti-inflammatory properties. However, poor solubility, rapid metabolism, and the knowledge gap on its pain alleviation mechanism have limited the clinical application of bufalin. Hence, the purpose of this study is to illustrate the NPP alleviation mechanism of bufalin via chronic constriction injury (CCI). To address the concern on fast metabolism, bufalin-PLGA microspheres (MS) were prepared via membrane emulsification to achieve prolonged pain-relieving effects. Western blot, real-time PCR, immunofluorescence, and molecular docking were employed to demonstrate the therapeutic action of bufalin on NPP. The results showed enhanced thermal withdrawal latency (TWL) and mechanical withdrawal threshold (MWT) after the administration of both bufalin and bufalin-PLGA MS in the CCI rats. Prolonged pain-relieving effects for up to 3 days with reduced dose frequency was achieved via bufalin-PLGA MS. In the CCI rats treated with bufalin-PLGA MS, the expression levels of protein and mRNA in TRPV1 and P2X7, both localized in the dorsal root ganglion (DRG), were reduced. Moreover, bufalin-PLGA MS effectively reduced the levels of IL-1β, IL-18, IL-6, and TNF-α in the CCI group. The results from molecular docking suggested a possible mechanism of NPP alleviation of bufalin through binding to P2X7 receptors directly. The administration of bufalin-PLGA MS prepared by membrane emulsification demonstrated promising applications for sustained effect on the alleviation of NPP.

As a traditional Chinese medicine (TCM), borneol has shown superior ability for anti-inflammatory and analgesic activities when coupled with other active ingredients from ancient times. Furthermore, borneol is believed to improve blood concentration and bioavailability of drugs. Thus, it has been paired with various TCM formulas since ancient time. The physiological barriers in human can cause significant limitations in drug efficiency as the drug is primarily restricted from entering into blood and brain. Borneol has been proven to enhance the permeability of biological barriers such as the blood–brain, transdermal, corneal, and intestinal barriers. Moreover, growing interest has been shown in the drug delivery system design for trans-barrier transport involving borneol. Nano-drug delivery system with increased surface area and improved active sites, has been applied to increase the bioactivity of water insoluble drugs. Nano-drug delivery system has been used to enhance drug efficacy by reducing the time of action as compared to conventional administration approach of TCM formulas. Given its ability to enhance cross-barrier permeation and drug efficacy, borneol has been integrated into TCM formulas of drug delivery system for precise and prolonged targeting at tumor sites. However, the design and preparation of a drug delivery system consisting of borneol still face great challenges. Current research fails to unravel the difference in mechanism of action between nano-drug delivery systems comprised of borneol and conventional drug systems coupled with borneol. Enhanced penetration of borneol in drug delivery system is rarely verified compared to conventional administration with identical drug formulation consisting of borneol regarding dosage and medical indications. This study outlines the current state of research on the properties, formulation and pharmacological effects of borneol, allowing cross-comparison of borneol coupled with single compound and classical TCM formulas for various medical indications. This study aims to provide insights into the design of borneol-based enhanced cross-barrier delivery drug formulation, and the potential development of nano-drug system for TCM formulas with borneol for enhanced bioavailability.

The development of injectable bio-stimulating polycaprolactone (PCL) microspheres for wound healing has strict requirement on size and morphology control, particularly favoring microspheres within the range between 20-50 µm. PCL microspheres with smaller sizes are phagocyted at rapid rate while larger microspheres could cause inflammation. Homogenization can be regarded as an irreversible process to generate microspheres of particular size range while it still remains as the most common approach for microspheres production. Membrane emulsification technology shows great potential in fine tailoring of microspheres while still holds promising ability for scale-up production. Membranes with uniform large pores and dual hydrophilicity might be capable of the production of large microspheres via emulsification with tailorable size distribution. The aim of this study is to verify the feasibility of PVDF membranes with large pores on the generation of PCL microspheres via the combined crystallization diffusion (CCD) approach. The effect of dope solution concentration and PVDF molecular weights on membrane morphologies and the corresponding microspheres characteristics were investigated. Results showed that concentration of 20 wt% produced microspheres at desirable size of 24.14 µm and the optimal span of 0.53. Microspheres with narrow distribution showed the highest drug loading efficiency of baicalin at 8.42 %. The baicalin loaded PCL microspheres presented gradual release of drug release over 33-day of in vitro testing and significantly improved cell growth rate of 111.67 % as compared to the ones prepared by homogenization approach. The wound healing ability was enhanced after the treatment of baicalin-loaded PCL microspheres as compared to empty loaded PCL microspheres.

This work focuses on the energy analysis of the membrane concentration systems that process traditional Chinese medicine extracts with dynamic properties incorporated, particularly for reverse osmosis (RO) and membrane distillation (MD) processes. The evaluation of process energy consumption was achieved by integrating the empirical properties correlations of Brix and other characteristics properties of the feed (e.g., density and heat capacity). The dynamic SEC analysis for RO process was largely dependent on the feed pressure, reported at 50 kWh/m³ at feed pressure of 0.9 MPa with less than 50% water removal. The occurrence of foaming at above 50% water removal caused discrepancies between the simulated flux results and the experimentally acquired results in RO, whereas the estimated dynamic SEC for MD process did not show a strong correlation with the temperatures selected in this study, ranging from 900 to 1000 kWh/m³. This approach can be adapted into the design and zoptimization for the concentration process of other herbal extracts by membrane technologies, allowing comprehensive understanding into the energy analysis in future study.