Polymer-based biodegradable drug delivery systems in pain management

How Biodegradable Polymers Can be Effective Drug Delivery Systems for Cannabinoids? Prospectives and Challenges

Cannabinoids are compounds found in and derived from the Cannabis plants that have become increasingly recognised as significant modulating factors of physiological mechanisms and inflammatory reactions of the organism, thus inevitably affecting maintenance of homeostasis. Medical Cannabis popularity has surged since its legal regulation growing around the world. Numerous promising discoveries bring more data on cannabinoids' pharmacological characteristics and therapeutic applications. Given the current surge in interest in the medical use of cannabinoids, there is an urgent need for an effective method of their administration. Surpassing low bioavailability, low water solubility, and instability became an important milestone in the advancement of cannabinoids in pharmaceutical applications. The numerous uses of cannabinoids in clinical practice remain restricted by limited administration alternatives, but there is hope when biodegradable polymers are taken into account. The primary objective of this review is to highlight the wide range of indications for which cannabinoids may be used, as well as the polymeric carriers that enhance their effectiveness. The current review described a wide range of therapeutic applications of cannabinoids, including pain management, neurological and sleep disorders, anxiety, and cancer treatment. The use of these compounds was further examined in the area of dermatology and cosmetology. Finally, with the use of biodegradable polymer-based drug delivery systems (DDSs), it was demonstrated that cannabinoids can be delivered specifically to the intended site while also improving the drug's physicochemical properties, emphasizing their utility. Nevertheless, additional clinical trials on novel cannabinoids' formulations are required, as their full spectrum therapeutical potential is yet to be unravelled.

Nebulizer systems: a new frontier for therapeutics and targeted delivery

Drug delivery via the pulmonary route is a cornerstone in the pharmaceutical sector as an alternative to oral and parenteral administration. Nebulizer inhalation treatment offers multiple drug administration, easily employed with tidal breathing, suitable for children and elderly, can be adapted for severe patients and visible spray ensures patient satisfaction. This review discusses the operational and mechanical characteristics of nebulizer delivery devices in terms of aerosol production processes, their usage, benefits and drawbacks that are currently shaping the contemporary landscape of inhaled drug delivery. With the advent of particle engineering, novel inhaled nanosystems can be successfully developed to increase lung deposition and decrease pulmonary clearance. The above-mentioned advances might pave the path for treating a life-threatening disorder like severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which is also discussed in the current state of the art.

Statistically optimized pentazocine loaded microsphere for the sustained delivery application: Formulation and characterization

Pentazocine (PTZ) is a narcotic analgesic used to manage moderate to severe, acute and chronic pains. In this study, PTZ loaded Ethyl cellulose microsphere has been formulated for sustained release and improved bioavailability of PTZ. These microspheres were fabricated by oil in water emulsion solvent evaporation technique. A three factorial, three levels Box-Behnken design was applied to investigate the influence of different formulation components and process variables on the formulation response using the numeric approach through the design expert^® software. All the formulations were characterized for the morphology, different physicochemical properties and the results were supported with the ANOVA analysis, three dimensional contour graphs and regression equations. The maximum percentage yield was 98.67% with 98% entrapment of PTZ. The mean particle size of the formulations ranges from 50–148μm, which directly relates to the concentration of polymer and inversely proportional to the stirring speed. SEM revealed the spherical shape of PTZ microspheres with porous structures. These are physically, chemically and thermally stable as confirmed through Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD) and thermal gravimetric (TG) analysis respectively. The microspheres provided a sustained release of the PTZ for more than 12 hours, following zero order with fickian and non fickian diffusion. The results indicate that prepared microspheres can be a potential drug delivery system (DDS) for the delivery of PTZ in the management of pains.

Ketamine-polymer based drug delivery system for prolonged analgesia: recent advances, challenges and future prospects

Introduction: With a sharp increase in NSAIDs and opioid use for chronic pain conditions associated with traumatic injuries and diseases, there has been an escalated risk of life-threatening side effects (cardiac and respiratory malfunction), inadvertent overdose, and even death. Their short duration of action and toxicity induces the need to develop extended-release analgesic drug formulations based on safe drugs like ketamine.Areas covered: This review presents progressive breakthroughs in pain control strategies for augmenting patient's comfort and minimizing unnecessary adverse effects associated with NSAIDs and opioids. Advantages of using ketamine, a dissociative anesthetic and potent analgesic over opioids have been elaborated here for the development of advanced sustained-release analgesic drug formulations based on ketamine and polymers (hydrogels, microparticles, and nanoparticles) as mainstream systems. These systems can be very promising in the resource-constrained healthcare set-up where frequent drug dosing at short time intervals is extremely challenging. PubMed, Embase, Google Scholar electronic databases, and clinical websites were used for conducting extensive research.Expert opinion: Controlled drug release analgesic systems can significantly reduce the burden of repeated drug dosing and opioid drug dependency, maximizing the function of analgesic drugs for clinical translation, and improving the quality of life of those living with pain.

Self-assembly of stimuli-responsive imine-linked calix[4]arene nanocapsules for targeted camptothecin delivery

Here we report template-free synthesis of imine-linked calix[4]arene hollow nanocapsules and their utility in the effective delivery of a poorly soluble cancer drug into tumor cells.

Electrospun PLGA Nanofiber Scaffolds Release Ibuprofen Faster and Degrade Slower After In Vivo Implantation

While delayed delivery of non-steroidal anti-inflammatory drugs (NSAIDs) has been associated with improved tendon healing, early delivery has been associated with impaired healing. Therefore, NSAID use is appropriate only if the dose, timing, and mode of delivery relieves pain but does not impede tissue repair. Because delivery parameters can be controlled using drug-eluting nanofibrous scaffolds, our objective was to develop a scaffold for local controlled release of ibuprofen (IBP), and characterize the release profile and degradation both in vitro and in vivo. We found that when incubated in vitro in saline, scaffolds containing IBP had a linear release profile. However, when implanted subcutaneously in vivo or when incubated in vitro in serum, scaffolds showed a rapid burst release. These data demonstrate that scaffold properties are dependent on the environment in which they are placed and the importance of using serum, rather than saline, for initial in vitro evaluation of biofactor release from biodegradable scaffolds.

Preparation and characterization of teniposide PLGA nanoparticles and their uptake in human glioblastoma U87MG cells

Many studies have demonstrated the uptake mechanisms of various nanoparticle delivery systems with different physicochemical properties in different cells. In this study, we report for the first time the preparation and characterization of teniposide (VM-26) poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles (NPs) and their cellular uptake pathways in human glioblastoma U87MG cells. The nanoparticles prepared with oil-in-water (O/W) single-emulsion solvent evaporation method had a small particle size and spherical shape and provided effective protection against degradation of teniposide in PBS solution. Differential scanning calorimeter (DSC) thermograms concluded that VM-26 was dispersed as amorphous or disordered crystalline phase in the PLGA matrix. A cytotoxicity study revealed that, in a 24h period, blank PLGA NPs had no cytotoxicity, whereas teniposide-loaded PLGA NPs (VM-26-NPs) had U87MG cytotoxicity levels similar to free teniposide. Confocal laser scanning microscopy (CLSM) and transmission electron microscopy (TEM) images showed the distribution and degradation processes of nanoparticles in cells. An endocytosis inhibition test indicated that clathrin-mediated endocytosis and macropinocytosis were the primary modes of engulfment involved in the internalization of VM-26-NPs. Our findings suggest that PLGA nanoparticles containing a sustained release formula of teniposide may multiplex the therapeutic effect and ultimately degrade in lysosomal within human glioblastoma U87MG cells.

Superhydrophobic materials for tunable drug release: using displacement of air to control delivery rates

We have prepared 3D superhydrophobic materials from biocompatible building blocks, where air acts as a barrier component in a porous electrospun mesh to control the rate at which drug is released. Specifically, we fabricated poly(ε-caprolactone) electrospun meshes containing poly(glycerol monostearate-co-ε-caprolactone) as a hydrophobic polymer dopant, which results in meshes with a high apparent contact angle. We demonstrate that the apparent contact angle of these meshes dictates the rate at which water penetrates into the porous network and displaces entrapped air. The addition of a model bioactive agent (SN-38) showed a release rate with a striking dependence on the apparent contact angle that can be explained by this displacement of air within the electrospun meshes. We further show that porous electrospun meshes with higher surface area can be prepared that release more slowly than control nonporous constructs. Finally, the entrapped air layer within superhydrophobic meshes is shown to be robust in the presence of serum, as drug-loaded meshes were efficacious against cancer cells in vitro for >60 days, thus demonstrating their applicability for long-term drug delivery.

In vitro characterisation of calcium phosphate biomaterials loaded with lidocaine hydrochloride and morphine hydrochloride

Calcium phosphate substitutes drug delivery systems are well known substances used in minor bone void-filling to release their therapeutic agent in situ. Few studies associating anaesthetics and analgesics have been performed to date. The aim of this work was to study the association of the analgesic, morphine, and the local anaesthetic, lidocaine, with a calcium deficient apatite matrix. Three types of biomaterials i.e. powders, granules and blocks, were prepared by isostatic compression, wet granulation and a combination of the two, evaluated and compared. The chemical structure of the associated therapeutic agent was studied and the characteristics of the drug delivery systems were appraised in terms of drug release. The integrity of the lidocaine hydrochloride structure, as determined by RMN (1)H, was confirmed regardless of the formulation technique used (isostatic compression or wet granulation). However, analyses of morphine hydrochloride by RMN (1)H revealed slight structural modifications. The association and formulation techniques that were used made it possible to obtain an in vitro release time varying from 1 to 4 days for lidocaine hydrochloride and from 1 to 3 days for morphine hydrochloride.