Local Drug Delivery System Research Articles

Chemically Bound Resorbable Ceramics as an Antibiotic Delivery System in the Treatment of Purulent–Septic Inflammation of Bone Tissue

Local drug delivery systems are an effective approach in the treatment of purulent–septic inflammation of bone tissue. Chemically bonded multiphase ceramics based on calcium-deficient carbonate-substituted hydroxyapatite combine resorbability, osteoconductivity, and the possibility of volumetric incorporation of antibiotics. Macroporosity is regulated by the concentration of polyethylene glycol granules introduced into the initial powder composition, followed by their extraction. The selected conditions for the consolidation of the ceramic matrix and the extraction of PEG granules retain the activity of vancomycin, which is confirmed by the results of microbiological studies. The concentration of vancomycin and the porosity affect the local concentration and release of the antibiotic. The incorporation method provides a prolonged release of the antibiotic for up to 31 days. In vivo experiments with bone implantation have shown that chemically bound macroporous ceramics with incorporated vancomycin are a therapeutically effective carrier of the substance during the healing of bone defects in conditions of surrounding purulent–septic inflammation, and can be considered as a carrier for local antibacterial therapy, at the site of implantation.

Controlled release of vitamin D3 using a nanocellulose-based membrane

Epidemiological studies show that a significant fraction of the global population presents low levels of vitamin D3. In order to address this problem, one way to administer the vitamin is to incorporate it in novel drug delivery systems, such as transdermal devices. A possible substance for this purpose is cellulose, which has a long history of use in the health area. However, the application of nanostructured cellulose membranes, as local drug delivery systems, remains a challenge. To develop a crystalline nanocellulose membrane as a new tool for the release of vitamin D3. A new nanostructured membrane containing nanocellulose extracted from cotton linter and vitamin D3 was produced using the “casting” technique. The membrane was characterized using high-resolution scanning electron microscopy (FEG-SEM) and Fourier transform infrared spectroscopy (FT-IR). The kinetics of vitamin release was quantified using molecular spectroscopy (UV–Vis). The FT-IR spectra showed the presence of all the active components in the membrane sample, without structural alterations or the formation of new bonds. The FEG-SEM images showed the presence of vitamin crystals on the surface and in the interior of the membrane. The release of vitamin D3 occurred in a sustained manner, obtaining 3029 IU mL−1 of vitamin D3 in 60 min. The findings demonstrated that the membrane could be used for the sustained release of vitamin D3. This new biomaterial has potential as a new model for vitamin supplementation in individuals with vitamin D3 deficiency.

Silk Fibroin Hydrogel Reinforced With Magnetic Nanoparticles as an Intelligent Drug Delivery System for Sustained Drug Release.

Due to the well-known biocompatibility, tunable biodegradability, and mechanical properties, silk fibroin hydrogel is an exciting material for localized drug delivery systems to decrease the therapy cost, decrease the negative side effects, and increase the efficiency of chemotherapy. However, the lack of remote stimuli response and active drug release behavior has yet to be analyzed comparatively. In this study, we developed magnetic silk fibroin (SF) hydrogel samples through the facile blending method, loaded with doxorubicin hydrochloride (DOX) and incorporated with different concentrations of iron oxide nanoparticles (IONPs), to investigate the presumable ability of controlled and sustained drug release under the various external magnetic field (EMF). The morphology and rheological properties of SF hydrogel and magnetic SF hydrogel were compared through FESEM images and rheometer analysis. Here, we demonstrated that adding magnetic nanoparticles (MNPs) into SFH decreased the complex viscosity and provided a denser porosity with a bigger pore size matrix structure, which allowed the drug to be released faster in the absence of an EMF. Release kinetic studies show that magnetic SF hydrogel could achieve controlled release of DOX in the presence of an EMF. Furthermore, the drug release from magnetic SF hydrogel decreased in the presence of a static magnetic field (SMF) and an alternating magnetic field (AMF), and the release rate decreased even more with the higher MNPs concentration and magnetic field strength. Subsequently, Wilms' tumor and human fibroblast cells were cultured with almost the same concentration of DOX released in different periods, and cell viability was investigated using MTT assay. MTT results indicated that the Wilms' tumor cells were more resistant to DOX than the human fibroblasts, and the IC50 values were calculated at 1.82 0.001 and 2.73 0.004 (μg/ml) for human fibroblasts and Wilms' tumor cells, respectively. Wilms' tumor cells showed drug resistance in a higher DOX concentration, indicating the importance of controlled drug delivery. These findings suggest that the developed magnetic SFH loaded with DOX holds excellent potential for intelligent drug delivery systems with noninvasive injection and remotely controlled abilities.

Fabrication, GSH-responsive drug release, and anticancer properties of thioctic acid-based intelligent hydrogels

Injectable hydrogels are potential local drug delivery systems since they contain plenty of water and soft like biological tissues. Such hydrogels could be injected directly into the tumor site where the drug is released under the tumor microenvironment. However, drug loaded hydrogels for cancer treatment based on lipoic acid (natural small molecule) have not been exploited. Here, a novel poly(lipoic acid)-poly(ethylene glycol) (PEG-PTA) hydrogels were prepared through a two-step reaction. The hydrogels contained disulfide bonds, so they could be degraded via the thiol exchange reaction with the abundant GSH in the tumor microenvironment, and subsequently release the drug. The results in vitro and at cellular level showed that the hydrogels were degraded and released the drugs only in the presence of GSH. Therefore, the injectable GSH-responsive hydrogels are promising to be served as an intelligent drug delivery system for cancer treatment.

Management of bone diseases: looking at scaffold-based strategies for drug delivery.

The bone tissue can regenerate itself completely and continuously; however, large-scale bone defects may overpower this self-regenerative process. Furthermore, the aging population, the increment in obesity incidence, and the sedentary lifestyles are serious risk factors for bone diseases' development which are associated with the self-regenerative process's failure, high morbidity, and mortality rates. Thus, there is an ever-growing need for strategic approaches targeting bone replacement, its remodelling, and its regeneration. Bone scaffolds have successfully been used as synthetic bone grafts for many years, yet recent bone tissue engineering strategies attempt to explore their multifunctionality by investigating them as drug delivery systems. Bone diseases' treatments can be substantially difficult due to the avascular nature of the surrounding cartilage; thus, targeted drug delivery to the bone can be advantageous: it provides local high drug concentrations and minimizes adverse effects while securing a space for new, healthy tissue growth. Despite the promising scientific progress, studies underlining bone scaffolds' use as local drug delivery systems are not abundant. Hence, this work reviews bone scaffolds' therapeutic interest for local drug delivery in five distinct bone disorders-osteomyelitis, osteoporosis, osteoarthritis, osteosarcoma, and cancer bone metastasis. Additionally, it presents the challenges of this possible therapeutic approach and its future perspectives. Albeit bone scaffolds present therapeutic benefits by acting as drug delivery systems, further pre-clinical and clinical assessments are needed to strengthen their understanding and enable research evidence translation into clinical practice. The mismatch between scientific evolution and regulatory frameworks remains one of the major future challenges.

Assessing the In Vitro Antioxidant and Anti-inflammatory Activity of Moringa oleifera Crude Extract

Chronic inflammation and oxidative stress play a vital role in the pathogenesis of various diseases of the oral cavity including periodontal disease. Phytochemicals present in plants with antioxidant (AO) and anti-inflammatory properties could aid as a therapeutic adjunct in the management of these diseases. To assess the antioxidant and anti-inflammatory effects of aqueous and ethanolic extracts of Moringa oleifera Lam. (MOL) in an in vitro environment. Aqueous and ethanolic extracts of M. oleifera Lam. were prepared by maceration. Antioxidant activity was assessed by FRAP, hydroxyl radical scavenging activity, and DPPH radical scavenging assay. Anti-inflammatory activity was assessed by Albumin Denaturation Assay. Experiments were repeated thrice, and mean and standard deviation were calculated. Both the test substances exhibited significant antioxidant and anti-inflammatory activity, and aqueous extracts exhibited higher activity than ethanolic extract. The anti-inflammatory and antioxidant activity of M. oleifera Lam. could be further explored for the management of periodontal disease as a local drug delivery system with the extract could be developed.

Multiresponsive fluorinated polymers as a theranostic platform using 19F MRI

Drug delivery systems (DDSs) can significantly improve the biodistribution and pharmacokinetics of various drugs. Herein, we describe diblock polymers of poly(2-methyloxazoline) and N-(2,2′-difluoroethyl)acrylamide with N-[2-(ferrocenylcarboxamido)ethyl]acrylamide that can be used as advanced DDSs. These thermoresponsive diblock copolymers self-assemble when heated to body temperature but disassemble when exposed to oxidative conditions (reactive oxygen species, ROS), releasing their cargo. Moreover, our polymers are not prone to spontaneous oxidation by air or hydrogen peroxide under physiological conditions but are highly sensitive to ROS under acidic conditions. Advantageously, the biodistribution of our DDS can be monitored with fluorine-19 magnetic resonance imaging (19F MRI). Therefore, our polymers could be used in both local and systemic drug delivery systems in ROS-rich environments, such as tumors or inflamed tissues. Additionally, the properties of our polymers could be widely modified to meet the demands of various clinical applications. Overall, we demonstrate that our copolymers (i) release their cargo preferentially in an ROS-rich environment, (ii) are biocompatible, and (iii) can be easily visualized in vivo.

An Injectable Nanocomposite Hydrogel Improves Tumor Penetration and Cancer Treatment Efficacy

Hydrogel as a local drug depot can increase drug concentration at the tumor site. However, conventional drug-loaded hydrogel is typically formed by direct dissolution of drug molecules inside the hydrogel, which usually suffers from limited drug retention and poor tumor penetration. In this study, a nanocomposite hydrogel consisting of oxaliplatin (OXA)-conjugated G5 polyamidoamine (G5-OXA) and oxidized dextran (Dex-CHO) is constructed to improve local drug delivery. The OXA-containing nanocomposite hydrogel (denoted as PDO gel) is injectable and could maintain in vivo up to more than three weeks, which increases drug retention in tumor tissues. More interestingly, G5-OXA released from the PDO gel show potent tumor penetration mainly through an active transcytosis process. In vivo antitumor studies in an orthotopic 4T1 tumor model show that PDO gel significantly inhibits primary tumor growth as well as the metastasis. In addition, the PDO gel can also activate the immunosuppressive tumor microenvironment through immunogenic cell death effect, and further improves therapeutic efficacy with the combination of PD-1 antibody. These results demonstrate that the nanocomposite hydrogel can simultaneously enhance the retention and penetration of chemotherapeutic drugs via the combination of both advantages of hydrogel and nanoparticles, which provides new insights for the design of local drug delivery systems. Statement of significanceHydrogel represents an important class of local drug delivery depot. However, conventional drug-loaded hydrogel is usually achieved by direct dissolution of small drug molecules inside the hydrogel, which typically suffers from limited drug retention and poor tumor penetration. Herein, we developed a nanocomposite hydrogel, which could gradually degrade and release drug-conjugated small nanoparticles (∼ 6 nm) for improved tumor penetration through the combination of an active transcytosis process and a passive diffusion process. This nanocomposite hydrogel system improved tumor penetration and retention of drug in primary tumors as well as the drug deposition in lymph nodes, which significantly suppressed tumor growth and metastasis.

Cellulose-based composite scaffolds for bone tissue engineering and localized drug delivery.

Natural bone constitutes a complex and organized structure of organic and inorganic components with limited ability to regenerate and restore injured tissues, especially in large bone defects. To improve the reconstruction of the damaged bones, tissue engineering has been introduced as a promising alternative approach to the conventional therapeutic methods including surgical interventions using allograft and autograft implants. Bioengineered composite scaffolds consisting of multifunctional biomaterials in combination with the cells and bioactive therapeutic agents have great promise for bone repair and regeneration. Cellulose and its derivatives are renewable and biodegradable natural polymers that have shown promising potential in bone tissue engineering applications. Cellulose-based scaffolds possess numerous advantages attributed to their excellent properties of non-toxicity, biocompatibility, biodegradability, availability through renewable resources, and the low cost of preparation and processing. Furthermore, cellulose and its derivatives have been extensively used for delivering growth factors and antibiotics directly to the site of the impaired bone tissue to promote tissue repair. This review focuses on the various classifications of cellulose-based composite scaffolds utilized in localized bone drug delivery systems and bone regeneration, including cellulose-organic composites, cellulose-inorganic composites, cellulose-organic/inorganic composites. We will also highlight the physicochemical, mechanical, and biological properties of the different cellulose-based scaffolds for bone tissue engineering applications.

Construction of Local Drug Delivery System on Titanium-Based Implants to Improve Osseointegration.

Titanium and its alloys are the most widely applied orthopedic and dental implant materials due to their high biocompatibility, superior corrosion resistance, and outstanding mechanical properties. However, the lack of superior osseointegration remains the main obstacle to successful implantation. Previous traditional surface modification methods of titanium-based implants cannot fully meet the clinical needs of osseointegration. The construction of local drug delivery systems (e.g., antimicrobial drug delivery systems, anti-bone resorption drug delivery systems, etc.) on titanium-based implants has been proved to be an effective strategy to improve osseointegration. Meanwhile, these drug delivery systems can also be combined with traditional surface modification methods, such as anodic oxidation, acid etching, surface coating technology, etc., to achieve desirable and enhanced osseointegration. In this paper, we review the research progress of different local drug delivery systems using titanium-based implants and provide a theoretical basis for further research on drug delivery systems to promote bone–implant integration in the future.

Artificial intelligence-assisted development of in situ forming nanoparticles for arthritis therapy via intra-articular delivery

Intra-articular (IA) injection is grasping much interest due to the poor drug bioavailability at the targeted site of action which minimizes the effect of the orally administered moiety. Based on the integral role of non-steroidal anti-inflammatory drugs (NSAIDs) in the treatment of Rheumatoid Arthritis (RA), much effort is exerted to develop novel localized drug delivery systems to increase their bioavailability and minimize their side effects. Artificial intelligence (AI) is acquiring an increasing role in the design of experiments being an effective tool for saving both time and resources. Hence, the aim of this work was to develop, characterize and optimize targeted in-situ forming nano particles (ISNs) for IA delivery of piroxicam using Design® Expert as an AI-based application where a 33 full factorial experimental design was adopted. Morphological investigation, injectability, rheological studies, Fourier Transform Infrared Radiation (FTIR) as well as biological, histopathological, and biochemical examinations were performed to evaluate the optimized-ISNs. The optimized formulation, exhibiting a nano-sized particle size with a dense core, showed significant improvement in the histopathological findings compared to both the oral solution and the placebo. Additionally, the once-a-week IA administration of the optimized-ISNs proved a significant reduction in the protein expression of both STAT-3 and RANKL and the levels of anti-CCP and MCP-1 by almost 54 and 73%, respectively, coupled with a marked decline in the content of IL-17, MMP-3, NF-κB and TNF-α as compared to the positive control. In conclusion, the use of ISNs for intra-articular injection has demonstrated their effectiveness in piroxicam delivery for RA treatment.

Near-Infrared Light-Remote Localized Drug Delivery Systems Based on Zwitterionic Polymer Nanofibers for Combination Therapy.

Localized drug delivery systems (LDDS) have gained great interests because they can directly treat the tumors and minimize systematic toxicity, and maximize drug action by controlling release precisely at the tumor site. However, the resistance of the non-specific adsorption of biomolecules is also important to alleviate the inflammatory reactions and avoid the decrease in performance of LDDS. In this study, we develop a near infrared (NIR) light-triggered nanofibrous delivery system consisting of zwitterionic poly(2-methacryloyloxyethyl phosphorylcholine)-b-poly(ε-caprolactone) (PMPC-b-PCL) encapsulated with indocyanine green (ICG) and doxorubicin (DOX) for dual photothermal therapy and chemotherapy. The nanofibrous mat shows hydrophilic characteristics and good antifouling performance. Under mild NIR irradiation, ICG could convert NIR light into thermal energy that elevates the surrounding temperature above 45 °C. This thermal energy also markedly accelerates the DOX release from the nanofibrous mat due to softening of the nanofibers, indicating the drug release could be controlled and switched on/off by light-triggering. Moreover, this light-triggered thermal energy and releasing behavior contribute to enhancing the cell lethality. Intracellular DOX distribution confirms the more drugs release upon light irradiation. All results demonstrate the developed light-triggered drug release nanofibers as LDDS are biocompatible and antifouling as well as has the superior combinational chemotherapy/photothermal therapy.

Localized Drug Delivery Systems in High‐Grade Glioma Therapy—From Construction to Application

AbstractHigh‐grade gliomas are the most common and most malign primary brain tumors. Current therapy approaches only reach unsatisfactory results, still not providing a long‐lasting time to relapse or a curative treatment. A novel approach to overcome the present challenges of medical attendance, as drug resistance, systemic side effects, and limited drug availability due to the blood‐brain barrier, are localized drug delivery systems (DDSs), which are already used in clinical trials. Further development of this therapy regime may clearly improve patient's outcomes. In order to design compact, biocompatible, robust, and highly flexible systems which permit a prolonged drug release, a broad knowledge of the technical and medical field is required. Thus, this interdisciplinary article reviews different designs, testing, and validation models, and finally, clinical applications of localized DDSs, to utilize this available experience as a basis for the desperately needed reform of glioma treatment.

Glycosaminoglycan-based injectable hydrogels with multi-functions in the alleviation of osteoarthritis

Osteoarthritis (OA), as an “undead cancer”, causes a serious burden for both individuals and society. In this study, a glycosaminoglycan-based injectable hydrogel was prepared with hyaluronic acid (HA), chondroitin sulfate E disaccharide (ΔUA-diSE) and thermosensitive Pluronic F127 (PF127) to provide a new strategy for OA alleviation. Both in vitro and in vivo biological evaluations were introduced to investigate the slow-release capacity, related mechanisms, and effectiveness of PF-HA-diSE on OA. The results demonstrated that PF-HA-diSE could alleviate OA effectively by regulating the complement system, especially the formation of C5b-9, and its downstream signals. Interestingly, we also found that PF127 was not only a drug carrier, but may have the potential on inhibiting C5b-9 formation. Altogether, these findings provided a more effective local drug delivery system for glycosaminoglycans in better treatment of OA and related diseases.

Design, synthesis, and evaluation of a novel series of mono-indolylbenzoquinones derivatives for the potential treatment of breast cancer

Breast cancer is one of the most common cancers in the world, and pro-apototic drugs activating the apoptotic pathway are a strategy for anticancer therapy. To explore new antineoplastic agents, a series of novel mono-indolylbenzoquinone derivatives have been designed and synthesized. Compared with the lead bis-indolylbenzoquinones, most of the novel mono-indolylbenzoquinone derivatives have significantly increased their activity against A549, HeLa, and especially, MDA-MB-231 cell lines. Among them, 10d has the lowest IC50 value of 70 nM on MDA-MB-231 cells. Moreover, its oral toxicity is extremely low with an LD50 value of 374 mg/kg and no obvious liver and kidney damage to mice. 10d down-regulated Bcl-2, up-regulated Bax, and increased the release of cytochrome C, caspase3 and 9. 10d also up-regulated the expression of p53, catalase, and HTRA2/Omi. Therefore, 10d may exert its anticancer activity by activating apoptotic pathway and p53 expression. In vivo, 10d suppressed breast cancer 4T1 tumor growth with 36% inhibition ratio of tumor by intraperitoneal injection in mice. Furthermore, a cross-linked cyanoacrylate (CA)-based local sustained-release drug delivery systems (LSRDDSs) improved 10d anticancer activity to 49.8% inhibition of tumor growth. Taken together, 10d could be a promising drug candidate for clinical development to treat metastatic breast cancer.

Metal-organic framework-based hydrogel with structurally dynamic properties as a stimuli-responsive localized drug delivery system for cancer therapy

Metal-organic framework (MOF) is an exciting class of porous biomaterials that have been considered as a carrier to store and deliver therapeutic drugs. However, similar to other nanomaterials, the application of MOF in clinical settings is still limited because of premature diffusion of their payloads and tissue off-targeting behavior. To overcome these challenges, we designed an MOF-based hydrogel with structurally dynamic properties, i.e., self-healing and shear-thinning, as an injectable localized drug delivery platform. The drug-encapsulating MOF hydrogel is formed through a dynamic coordination bond cross-linkage between a doxorubicin-loaded MOF (MOF@DOX) particle and a homemade bisphosphonate-modified hyaluronic acid (HA-BP) polymeric binder. The HA-BP·MOF@DOX hydrogel demonstrates pH- and ATP-responsive drug release characteristic and efficiently kills cancer cells in vitro. The animal experiments reveal that the HA-BP·MOF@DOX hydrogel has enhanced capability in terms of tumor growth suppression as compared to the MOF@DOX group, which can be attributed to drug localization in hydrogel superstructure and sustained release at the tumor site. The presented injectable dynamic MOF-based hydrogel is a promising in vivo localized drug delivery system for cancer treatment. Herein, we report the self-healing and shear-thinning of MOF-based drug carrier cross-linked by coordinate bonds for the first time and provide new insights and a facile chemical strategy for designing and fabricating MOF-based biomaterials by using bisphosphonate-zinc interaction. Statement of significanceBisphosphonate-zinc interaction is a facile chemical strategy to cross-link metal-organic framework (MOF)-based hydrogel. The presented MOF-based hydrogel demonstrates structurally dynamic properties, including smooth injectability, self-healing, and shear-thinning. The developed MOF-based hydrogel possesses pH- and ATP-responsive drug release characteristic and kills cancer cells in vitro efficiently. The dynamic MOF-based hydrogel shows enhanced in vivo anticancer activity as compared to pure MOF particles. Self-healing and shear-thinning of metal-ligand cross-linked MOF-based drug delivery system are reported for the first time, thus providing new insights for the design and fabrication of MOF-based biomaterials.

Design and Comparative Evaluation of Vancomycin HCl-Loaded Rosin-Based In Situ Forming Gel and Microparticles.

Vancomycin hydrochloride (HCl) is a glycopeptide antibiotic used to treat serious or life-threatening infections, and it reduces plaque scores and gingivitis in periodontal patients. In this study, vancomycin HCl was incorporated into rosin in situ forming gel (ISG) and rosin in situ forming microparticles (ISM) to generate a local drug delivery system to treat periodontal disease. The physical properties of the ISG and ISM were measured, including pH, viscosity, injectability, adhesion properties, in-vitro transformation, and drug release. Moreover, the effectiveness of antimicrobial activity was tested using the agar-cup diffusion method against Staphylococcus aureus, Streptococcus mutans, Porphyromonas gingivalis, and Escherichia coli. Vancomycin HCl-loaded rosin-based ISG and ISM had a pH value in the range of 5.02–6.48 and exhibited the ease of injection with an injection force of less than 20 N. Additionally, the lubricity effect of the external oil phase of ISM promoted less work of injection than ISG and 40–60% rosin-based ISM showed good emulsion stability. The droplet size of emulsions containing 40%, 50%, and 60% rosin was 98.48 ± 16.11, 125.55 ± 4.75, and 137.80 ± 16.8 µm, respectively. Their obtained microparticles were significantly smaller in diameter, 78.63 ± 12.97, 93.81 ± 10.53, and 118.32 ± 15.61 µm, respectively, because the particles shrank due to the solvent loss from solvent exchange. Moreover, increasing the concentration of rosin increased the size of microparticles. After phase transformation, all formulations had better plasticity properties than elasticity; therefore, they could easily adapt to the specific shape of a patient’s gum cavity. Both developed ISG and ISM presented inhibition zones against S. mutans and P. gingivalis, with ISG presenting significantly more effectively against these two microbes (p < 0.05). The vancomycin HCl-loaded rosin ISG and ISM delayed drug release for 7 days with efficient antimicrobial activities; thus, they exhibit potential as the drug delivery systems for periodontitis treatment.

Smart stimuli-responsive implantable drug delivery systems for programmed and on-demand cancer treatment: An overview on the emerging materials

• Smart materials develop programmed and on-demand cancer treatment. • Tumor recurrence is prevented via multi-responsive implantable delivery systems. • Redox, enzyme and pH-responsive systems are described in programmable systems. • On-demand systems are regulated by NIR, ultrasound, electric and magnetic stimuli. • Applications of the smart systems are described for treatment of different tumors. Despite noteworthy developments in tumor therapy, cancer is still one of the main reasons for death worldwide. While present cures supply hopeful marks, they trigger harsh cytotoxicity, with limited success in preventing and recurrence of the disease. To overcome the mentioned issues, implantable biomaterials have been developed as promising systems for the local delivery of therapeutic agents to cancerous tissues. Due to the unique characteristics of biocompatible polymers, they have been used in different approaches of localized drug delivery to ensure accurate control over the release of chemotherapy drugs, genes, proteins, and peptides. In this review article, the recent progress in stimuli-responsive implantable drug delivery systems for preventing tumor recurrence and suppressing tumors are reported. In particular, we reviewed redox-, enzyme-, and pH-responsive systems in programmable drug delivery and the near-infrared-, ultrasound-, electric-, and magnetic-regulated release in on-demand local drug delivery systems. The preparation process, physicochemical characteristics of implantable materials, and kinetic models of the drug release from these platforms were also discussed in detail.

Subgingival application of 0.5% Azithromycin gel as a local drug delivery system as an adjunct to scaling and root planing in controlled diabetic patients- An in vivo study

Introduction: A recent trend involving the use of local delivery systems to deliver chemotherapeutic agents implies improved periodontal health. As part of this study, a locally delivered 0.5% azithromycin gel was evaluated for its clinical and microbiological efficacy in treating chronic periodontitis patients with controlled diabetes.&#x0D; Material and Methods: The split-mouth study design was used in this randomized control trial. The study included 50 sites from 25 patients who had pocket depths greater than 5 mm and were diagnosed with chronic periodontitis. Two treatment groups were randomly assigned: scaling and root planing only (control group) or scaling and root planing with 0.5% azithromycin gel (test group). At selected sites, gingival index, probing pocket depth, and clinical attachment level were analyzed for both groups at baseline, 6 weeks, and 12 weeks.&#x0D; Result &amp; observations: Both the test and control groups had improved parameters when compared to baseline. The depth of the probing pocket was 6.64±1.07 mm and 7.36±1.15 mm at baseline, which decreased to 4.84±0.59 mm and 4.32±0.98 mm respectively at 12 weeks. The difference was statistically significant at p&lt;0.001. Statistically significant difference in clinical attachment levels between baseline and 12 weeks, at p&lt;0.001. The results of all microbiological categories improved significantly in both groups, while the test group showed a greater improvement.&#x0D; Conclusion: It was concluded that locally delivered azithromycin could be beneficial in treating chronic periodontitis patients with diabetes when used in conjunction with scaling and root planing.&#x0D; Keywords: Local drug delivery, Periodontal disease, Diabetes, Azithromycin gel.

Optimized-dose lidocaine-loaded sulfobutyl ether β-cyclodextrin/hyaluronic acid hydrogels to improve physical, chemical, and pharmacological evaluation for local anesthetics and drug delivery systems

Optimized-dose lidocaine-loaded sulfobutyl ether β-cyclodextrin/hyaluronic acid hydrogels to improve physical, chemical, and pharmacological evaluation for local anesthetics and drug delivery systems