Controlled Drug Delivery Systems Research Articles

Advancement in gastro retentive floating tablet: an updated review

The widespread use of oral dose forms in disease treatment may lead to inadequate pharmacokinetic properties due to rapid transit through the gastrointestinal tract. This makes it challenging to achieve therapeutic levels in situations where the medicine is barely soluble. Studies have been conducted to identify formulations that enhance these characteristics while extending stomach residence time, with gastro retentive controlled drug delivery systems being beneficial. This study evaluates recent developments in FDDS, focusing on how these systems function to make dosage forms float in stomach fluid for gradual release, better gastric retention, and improved bioavailability of oral medicine. It discusses the pharmaceutical importance of GRDDS, stomach physiology, and factors controlling gastric retention. The review also discusses the preparation of GRDDS, polymeric materials, dosage form evaluation, and comparisons between conventional and GRDDS. In this abstract, we will keep an eye on updated review on recent advancement in gastro retentive floating tablet.

Far-red light-triggered cargo release from liposomes bound to a photosensitizer-cellulose nanofiber hydrogel

In our research we used the anionic nanofibrillar cellulose (ANFC) as a platform for far-red light-induced release of cargo from liposomes. In contrast to previous works, where photosensitizers are usually in the liposomal bilayers, we used a cellulose-binding dye. Our phthalocyanine derivative has been shown to bind very strongly to cellulose and cellulose nanofiber hydrogels, allowing us to place it outside of the liposomes. Both the sensitizer and cationic liposomes bind strongly to the ANFC after mixing, making the system easy to fabricate. Upon light activation, the photosensitizer generates reactive oxygen species (ROS) within the ANFC hydrogel, where the reactive oxygen species oxidize unsaturated lipids in the liposomal membrane, which makes the liposomes more permeable, resulting in on-demand cargo release. We were able to achieve ca. 70 % release of model hydrophilic cargo molecule calcein from the hydrogels with a relatively low dose of light (262 J/cm2) while employing the straightforward fabrication techniques. Our system was remarkably responsive to the far-red light (730 nm), enabling deep tissue penetration. Therefore, this very promising novel cellulose-immobilized photosensitizer liposomal platform could be used as a controlled drug delivery system, which can have applications in externally activated coatings or implants.

Wireless electrostimulation for cancer treatment: An integrated nanoparticle/coaxial fiber mesh platform

Cancer, namely breast and prostate cancers, is the leading cause of death in many developed countries. Controlled drug delivery systems are key for the development of new cancer treatment strategies, to improve the effectiveness of chemotherapy and tackle off-target effects. In here, we developed a biomaterials-based wireless electrostimulation system with the potential for controlled and on-demand release of anti-cancer drugs. The system is composed of curcumin-loaded poly(3,4-ethylenedioxythiophene) nanoparticles (CUR/PEDOT NPs), encapsulated inside coaxial poly(glycerol sebacate)/poly(caprolactone) (PGS/PCL) electrospun fibers. First, we show that the PGS/PCL nanofibers are biodegradable, which allows the delivery of NPs closer to the tumoral region, and have good mechanical properties, allowing the prolonged storage of the PEDOT NPs before their gradual release. Next, we demonstrate PEDOT/CUR nanoparticles can release CUR on-demand (65 % of release after applying a potential of −1.5 V for 180 s). Finally, a wireless electrostimulation platform using this NP/fiber system was set up to promote in vitro human prostate cancer cell death. We found a decrease of 67 % decrease in cancer cell viability. Overall, our results show the developed NP/fiber system has the potential to effectively deliver CUR in a highly controlled way to breast and prostate cancer in vitro models. We also show the potential of using wireless electrostimulation of drug-loaded NPs for cancer treatment, while using safe voltages for the human body. We believe our work is a stepping stone for the design and development of biomaterial-based future smarter and more effective delivery systems for anti-cancer therapy.

Successful controlled release of cyclophosphamide from tert-butylamine-functionalized large-pore SBA-15

ABSTRACT Controlled drug delivery systems operate effectively using the correct carrier/host design that respects the physicochemical characteristics of the drug. LP-SBA-15 shows exceptional qualities as a new host for cyclophosphamide (CP) delivery due to its low toxicity, high biocompatibility, and biodegradability in vivo. Cyclophosphamide is a phosphoramide-derived alkylating compound currently used for treating autoimmune diseases and slowing or restraining cancer cell growth. LP-SBA-15 was synthesized and functionalized using 0%–15%–25% tert-Butylamine (TBA) to incorporate the drug. The composite was characterized by XRD, N2 physisorption, UV-VIS, and FTIR spectroscopy. Absorption and release of CP were assessed by UV-VIS spectrophotometry. The release mechanism from the functionalized LP-SBA-15 matrix was evaluated by fitting experimental data with different mathematical models. The Ritger – Peppas, Weibull, and First-Order models were the most appropriate, as confirmed by the coefficient of determination R2 and other statistics. We designed LP-SBA-15 functionalized with 15% TBA as a suitable system that achieves a moderate initial release rate and maintains a constant rate over long periods, enabling the nanodrug (CP) to concentrate on tumor tissue and not on normal cells while simultaneously reaching adequate levels over time and avoiding harmful side effects due to their deposition.

A Research Work on Design, Development and In-Vitro Evaluation of Losartan Potassium Loaded Pectinate Microspheres

One of the special and innovative drug delivery strategies is the use of microspheres, which can increase a drug's effectiveness by preventing drug dilution in bodily fluids, allowing drug localization and targeting at a specific site, and maintaining drug concentration between MEC and MTC levels.Microspheres are characterized as roughly spherical, solid particles with sizes between 1 to 1000 μm that are intended to be covered in protective materials such as polymeric or waxy coatings. One of the more innovative methods in the field of oral controlled drug delivery systems is the use of microsphere dosage forms, which target a specific area of the body for a prolonged period of time, allowing for more effective local drug delivery as well as improved systemic drug. The % yield of all the losartan potassium loaded pectinate microsphere formulations (LM1 to LM5) was found within the range from 76.74 ± 3.79 % to 89.06 ± 2.67 %.The % entrapment efficiency and particle size of the prepared losartan potassium loaded pectinate microsphere formulations (LM1 to LM5) was found within the range from 63.68 ± 3.55 % to 84.78 ± 2.27 % and 0.78 ± 0.14 mm to 0.91 ± 0.05 mm respectively. Formulations LM1 to LM5 showed 2.12 % to 12.46 % mucoadhesion up to 6 hours in simulated gastric fluid (pH 1.2, 0.1N HCl) and 74.28 % to 96.04 % mucoadhesion up to 6 hours in simulated intestinal fluid (phosphate buffer, pH 6.8).

3D Printing Chitosan-based Nanobiomaterials for Biomedicine and Drug Delivery: Recent Advances on the Promising Bioactive Agents and Technologies

Abstract: 3D bioprinting is a novel technology that has gained significant attention recently due to its potential applications in developing simultaneously controlled drug delivery systems (DDSs) for administering several active substances, such as growth factors, proteins, and drug molecules. This technology provides high reproducibility and precise control over the fabricated constructs in an automated way. Chitosan is a naturalderived polysaccharide from chitin, found in the exoskeletons of crustaceans such as shrimp and crabs. Chitosan- based implants can be prepared using 3D bioprinting technology by depositing successive layers of chitosan- based bioink containing living cells and other biomaterials. The resulting implants can be designed to release drugs at a controlled rate over an extended period. The use of chitosan-based implants for drug delivery has several advantages over conventional drug delivery systems. Chitosan is biodegradable and biocompatible, so it can be safely used in vivo without causing any adverse effects. It is also non-immunogenic, meaning it does not elicit an immune response when implanted in vivo. Chitosan-based implants are also costeffective and can be prepared using simple techniques. 3D bioprinting is an emerging technology that has revolutionized the field of tissue engineering by enabling the fabrication of complex 3D structures with high precision and accuracy. It involves using computer-aided design (CAD) software to create a digital model of the desired structure, which is then translated into a physical object using a 3D printer. The printer deposits successive layers of bioink, which contains living cells and other biomaterials, to create a 3D structure that mimics the native tissue. One of the most promising applications of 3D bioprinting is developing drug delivery systems (DDSs) to administer several active substances, such as growth factors, proteins, and drug molecules. DDSs are designed to release drugs at a controlled rate over an extended period, which can improve therapeutic efficacy and reduce side effects. Chitosan-based implants have emerged as a promising candidate for DDSs due to their attractive properties, such as biodegradability, biocompatibility, low cost, and nonimmunogenicity. 3D bioprinting technology has emerged as a powerful tool for developing simultaneously controlled DDSs for administering several active substances. The rationale behind integrating 3D printing technology with chitosan-based scaffolds for drug delivery lies in the ability to produce customized, biocompatible, and precisely designed systems that enable targeted and controlled drug release. This novel methodology shows potential for advancing individualized healthcare, regenerative treatments, and the creation of cutting- edge drug delivery systems. This review highlights the potential applications of 3D bioprinting technology for preparing chitosan-based implants for drug delivery.

Patient-Centric Approaches to Gastroretentive Floating Tablets: Tailoring for Diverse Clinical Needs

Gastroretentive tablets have emerged as a promising platform for controlled drug delivery, offering the potential for prolonged gastric residence time and enhanced therapeutic outcomes. This comprehensive review explores the paradigm shift towards patient-centric approaches in the development of gastroretentive tablets. The journey begins with an examination of the historical evolution of gastroretentive technologies, tracing advancements in formulation techniques, materials, and technologies that have paved the way for patient-centric designs. The review delves into patient-centric formulation strategies tailored for diverse populations, including pediatrics and geriatrics. It highlights the importance of considering patient-specific needs, preferences, and physiological characteristics in optimizing dosage forms. Regulatory considerations and compliance-enhancing features are scrutinized, providing insights into the delicate balance between personalized medicine and regulatory expectations. Real-world applications are illuminated through case studies, offering success stories across pediatric, geriatric, and personalized medicine contexts. Clinical outcomes, including adherence metrics and patient satisfaction, provide tangible evidence of the impact of patient-centric gastroretentive tablets. Challenges in formulation development and regulatory implementation are critically examined, with a focus on technical hurdles and strategies for navigating evolving regulatory landscapes. The conclusion distills key findings and outlines implications for future research and clinical practice, emphasizing continued innovation, strategic regulatory engagement, and interdisciplinary collaboration. This review serves as a comprehensive resource for researchers, clinicians, and regulatory professionals engaged in advancing patient-centric gastroretentive tablets. It offers a roadmap for the integration of innovative technologies into clinical practice, fostering a patient-centered approach in the evolution of controlled drug delivery systems.

Hydrophilic and hydrophobic drug release from core (polyvinylpyrrolidone)-sheath (ethyl cellulose) pressure-spun fibers

A core-sheath structure is one of the methods developed to overcome the challenges often faced when using monolithic fibers for drug delivery. In this study, fibers based on polyvinylpyrrolidone (core) and ethyl cellulose (sheath) were successfully produced using a novel core-sheath pressure-spinning process. For comparison, these two polymers were also processed into as blend fibers. All samples were then investigated for their performances in releasing water-soluble ampicillin (AMP) and poorly water-soluble ibuprofen (IBU) model drugs. Scanning electron,digital and confocal microscopy confirmed that fibers with a core-sheath structure were successfully made. Fourier transform infrared spectroscopy showed the success of the pressure-spinning technique in encapsulating AMP/IBU in all fiber samples. Compared to blend fibers, the core-sheath fibers had better performance in encapsulating both water-soluble and poorly water-soluble drugs. Moreover, the core-sheath structure was able to reduce the initial burst release and provided a better sustained release profile than the blend fiber analog. In conclusion, the pressure-spinning method was capable of producing core-sheath and blend fibers that could be used for the loading of either hydrophilic or hydrophobic drugs for controlled drug delivery systems.

Gastroretentive Drug Delivery Systems with improved Floating and Swelling Capabilities

For medications with an absorption window in the stomach and upper part of small intestine, a controlled drug delivery system with a longer stomach residence duration can be particularly useful. Rapid gastrointestinal transit may cause drug delivery system above the absorption zone to only partially release drug, which would reduce the supplied dose's effectiveness. The main drawbacks are linked to the non-uniformity of drug absorption across the alimentary canal and the inter- and intra-subject variability of gastro-intestinal transit time. The bioavailability of medications is predicted to be improved by floating delivery systems, which are designed to stay buoyant on the gastric contents for an extended period of time. Floating in combination with swellable system gaining attention due to their wide applicability in the targeting of drugs to stomach. These floating and swellable tablet have the advantage that they remain buoyant and swells to 2-3 folds in gastric fluid.

In vitro inhibition of uterine contractions using electrospun nanofibers loaded with nifedipine and ML7.

To formulate a nanofiber-based controlled drug delivery system that could be effective in preventing uterine contractions and can be used for the treatment of preterm labor. We utilized uterine tissue samples obtained from ten pregnant women who underwent cesarean section at term to investigate the effect of nanofibers on spontaneous and induced myometrial contractions. We prepared nifedipine and ML7-loaded nanofibers using the electrospinning method with Poly(D,L-lactide-co-glycolide) (PLGA) polymer, resulted in seven groups of nanofibers, including a control group. Group I served as the control, Group II was non-drug loaded nanofiber, Group III was nifedipine (10-5 M) loaded nanofiber, Group IV was ML7 (3x10-5 M) loaded nanofiber, Group V was ML7 (3x10-5 M) and nifedipine (10-5 M) nanofiber, Group VI was ML7 (3x10-5 M) and nifedipine (3x10-5 M) nanofiber, and Group VII was ML7 (3x10-5 M) and nifedipine (10-4 M) nanofiber. To evaluate the contractile response, the nanofibers loaded with different doses of ML7 and nifedipine were applied onto the tissue strips, and in vitro organ bath experiments were performed. Full-thickness uterine samples were cleared of the serosa and surrounding tissues, and eight strips (3x10 mm) were prepared from each sample. The seven different nanofiber formulations were gently placed and sutured onto the strips, with one strip always kept as the time control. We recorded spontaneous, KCl-induced, and stimulated cumulative oxytocin-induced contractions from all samples in all groups. After completing all experiments, the viability of the strips was checked, and weight measurement was recorded. The administration of drug-loaded polymers resulted in a significant decrease in both the frequency and intensity of spontaneous and induced contractions in all groups (p<0.01). No significant difference was observed between the control group and the non-drug-loaded nanofiber group in post hoc analysis (p=0.704). In terms of amplitude and frequency of contractions, the most significant decrease was observed in group VII at cumulative oxytocin doses compared to the control and non-drug-loaded nanofiber groups (p<0.05). Moreover, group VI also showed a significant decrease in contraction intensity and frequency compared to the control and non-drug-loaded nanofiber groups (p<0.05). While the use of nifedipine and/or ML7-loaded nanofibers decreased both intensity and frequency of contraction, this attenuation was not significant compared to the control and empty polymer groups. However, a more significant inhibition was observed when ML7 was used with nifedipine at doses of 3x10-5 M and 10-4 M. The results indicate that human uterine contractions can be inhibited using calcium channel blocker (nifedipine) and myosin light chain kinase inhibitor (ML7) loaded nanofibers in uterine tissue strips. These results strongly suggested the potential for the development of locally effective and safe controlled drug release systems to prevent premature birth.

Investigation on the structural and dynamical properties of cationic, anionic, and catanionic niosomes as multifunctional controlled drug delivery system for cabozantinib

BackgroundNiosomes are versatile nanocarriers for therapeutic compounds, and optimizing their structures via ionic surfactants can enhance their functionality considerably. Catanionic niosomes, which have the capability of both cationic and anionic niosomes, are attractive vehicles for drug delivery objectives. Here, we aim to design and evaluate catanionic niosome as a vehicle for anticancer agents. MethodsA molecular modeling pipeline was performed to model the physicochemical properties of cationic, anionic, and catanionic niosomes as a multifunctional drug delivery system for Cabozantinib. SPAN60 was used as the nonionic surfactant, cholesterol was the stabilizer, DOTAP and DCP were used as the cationic and anionic surfactants, respectively, and cabozantinib, an FDA-approved c-Met inhibitor was chosen as the drug compound. Some meaningful parameters relevant to the cabozantinib molecule and its characteristics in the bilayer, such as hydrogen bonding, total energy, the radius of gyration (Rgyr), mean square displacements (MSD), diffusion coefficient, and the radial distribution function (RDF) were evaluated and compared between the formulations. ResultsThe outcomes revealed that hydrogen bonding of cabozantinib is more probable with DOTAP, and the total energy of the drug is lower in anionic formulation (-180 kcal/mol). The MSD showed that cationic niosome restricts the movement of cabozantinib, while the drug could be efficiently released from the anionic niosome, and catanionic niosome can equilibrate the movement of the drug with a diffusion coefficient of 5.73 × 10−12 (m2/s). ConclusionsThis technique could effectively describe the behavior of drugs in various bilayer compositions, and the catanionic niosomes are potential multifunctional carriers for anticancer agents.

Gelation of acrylic acid with Ag+ and conversion to Ag nanoparticle as potential system for biomedical applications

Silver (Ag) has been used to cross-link poly (acrylic acid) (PAAc) to obtain antibacterial nanocomposite hydrogel for controlled drug delivery systems. Ag+/PAAc composite hydrogel was prepared by free radical aqueous polymerization of acrylic acid (AAc) using potassium persulfate (KPS) as the initiator in the presence of silver nitrate (AgNO3). Sodium borohydride (NaBH4) was used to reduce the Ag ions present within the hydrogel matrix to generate Ag nanoparticles (Ag NPs). Transmission electron microscopy (TEM) characterization of the sample indicated the formation of Ag nanoparticles that distributed uniformly in the PAAc networks. UV–visible spectrophotometry showed an absorption peak at 425 nm that attribute to the well-known surface Plasmon resonance of the Ag bound in NPs. X-ray diffraction (XRD) pattern showed the appearance of some peaks corresponding to the face-centered cubic (f.c.c.) Ag phase. Energy dispersive spectroscopy (EDS) studies revealed that Ag NPs are successfully formed inside the Ag+/PAAc composite hydrogel. The gelation and crosslinking of PAAc chains with Ag+ by strong interactions between Ag cations and polyanions, deprotonated carboxylic groups of PAAc were identified from the Fourier transform infrared (FTIR) spectrogram. Field emission scanning electron microscopy (FESEM) exhibited an interconnected porous structure with an average pore size of about 10 μ for composite hydrogel that can absorb 440 g water/g dried sample. Dried samples were also loaded with amoxicillin and antibiotic release was studied. The antimicrobial activity of the Ag+ and Ag-NPs hydrogels was tested against Staphylococcus aureus, Bacillus cereus, Pseudomonas aeruginosa and Escherichia coli.

Magnetic propelled hydrogel microrobots for actively enhancing the efficiency of lycorine hydrochloride to suppress colorectal cancer.

Research and development in the field of micro/nano-robots have made significant progress in the past, especially in the field of clinical medicine, where further research may lead to many revolutionary achievements. Through the research and experiment of microrobots, a controllable drug delivery system will be realized, which will solve many problems in drug treatment. In this work, we design and study the ability of magnetic-driven hydrogel microrobots to carry Lycorine hydrochloride (LH) to inhibit colorectal cancer (CRC) cells. We have successfully designed a magnetic field driven, biocompatible drug carrying hydrogel microsphere robot with Fe3O4 particles inside, which can achieve magnetic field response, and confirmed that it can transport drug through fluorescence microscope. We have successfully demonstrated the motion mode of hydrogel microrobots driven by a rotating external magnetic field. This driving method allows the microrobots to move in a precise and controllable manner, providing tremendous potential for their use in various applications. Finally, we selected drug LH and loaded it into the hydrogel microrobot for a series of experiments. LH significantly inhibited CRC cells proliferation in a dose- and time-dependent manner. LH inhibited the proliferation, mobility of CRC cells and induced apoptosis. This delivery system can significantly improve the therapeutic effect of drugs on tumors.

Transformable Magnetic Liquid-Metal Nanoplatform for Intracellular Drug Delivery and MR Imaging-Guided Microwave Thermochemotherapy.

Improved techniques for the administration of chemotherapeutic drugs are required to enhance tumor therapy efficacy and reduce the side effects of chemotherapy due to insufficient targeting and limited intratumoral drug release. Controlled drug delivery systems combined with thermotherapy are expected to play an important role in personalized tumor therapy. Herein, a novel microwave-responsive transformable magnetic liquid-metal (MLM) nanoplatform is designed for effective endosomal escape that facilitates intracellular drug delivery and enhanced anticancer therapy. The MLM nanoplatform exhibits a sensitive magnetic resonance imaging function for imaging-guided therapy and brilliant synergistic effects of chemotherapy with microwave thermal therapy to kill tumor cells. Once endocytosed by targeted tumor cells, the deep penetration of microwave energy can be absorbed by the MLM nanoplatform to convert heat and reactive oxygen species, which induces the shape transformation from nanospheres to large rods, resulting in the physical disruption of the endosomal membrane for intracellular drug release. Furthermore, the MLM nanoplatform synergistic therapy could activate immunomodulatory effects by M1 macrophage polarization and T cell infiltration, thus inhibiting tumor growth and lung metastasis. This work based on microwave-driven transformable magnetic liquid-metal nanoplatform provides novel ways to precisely control drug delivery and high-efficiency cancer therapy.

Formulation And Evaluation Of Osmotically Controlled Drug Delivery System Of An Anti-Diabetic Drug

Formulation And Evaluation Of Osmotically Controlled Drug Delivery System Of An Anti-Diabetic Drug

Droplet-based logic gates simulation of viscoelastic fluids under electric field

Nano and microfluidic technologies have shown great promise in the development of controlled drug delivery systems and the creation of microfluidic devices with logic-like functionalities. Here, we focused on investigating a droplet-based logic gate that can be used for automating medical diagnostic assays. This logic gate uses viscoelastic fluids, which are particularly relevant since bio-fluids exhibit viscoelastic properties. The operation of the logic gate is determined by evaluating various parameters, including the Weissenberg number, the Capillary number, and geometric factors. To effectively classify the logic gates operational conditions, we employed a deep learning classification to develop a reduced-order model. This approach accelerates the prediction of operating conditions, eliminating the need for complex simulations. Moreover, the deep learning model allows for the combination of different AND/OR branches, further enhancing the versatility of the logic gate. We also found that non-operating regions, where the logic gate does not function properly, can be transformed into operational regions by applying an external force. By utilizing an electrical induction technique, we demonstrated that the application of an electric field can repel or attract droplets, thereby improving the performance of the logic gate. Overall, our research shows the potential of the droplet-based logic gates in the field of medical diagnostics. The integration of deep learning classification algorithms enables rapid evaluation of operational conditions and facilitates the design of complex logic circuits. Additionally, the introduction of external forces and electrical induction techniques opens up new possibilities for enhancing the functionality and reliability of these logic gates.

Biphasic Porous Bijel-Like Structures with Hydrogel Domains as Controlled Drug Delivery Systems.

Bijels are a peculiar type of Pickering emulsion that have a bicontinuous morphology and are stabilised by a jammed layer of nanoparticles (NPs). Due to their double nature, their usage has increased in recent years in various fields, such as biological and food applications. In fact, they can release both hydrophilic and hydrophobic compounds simultaneously. An improvement to this structure is the use of a hydrophobic monomer like polycaprolactone as the organic phase, which is able to polymerise during the formation of the structure. Unfortunately, the structures formed in this way always have some drawbacks, such as their thermal stability or degradation when submerged in an aqueous medium. A number of studies have been carried out in which some parameters, such as the NPs or the monomer, were changed and their effect on the final product evaluated. In this work, the effect of modifying the aqueous phase was studied. In particular, the effect of adding alginate, a biopolymer capable of forming a stable hydrogel in the presence of divalent cations, was analysed, as was the difference between soaking or not in CaCl2, the final system. Specific attention was paid to their swelling behaviour (150% vs. 25% of the blank sample), rheological properties (G' 100 kPa vs. 20 kPa of the blank sample) and their release performances. In this framework, complete release of hydrophilic drug vs. 20% in the blank sample was observed together with improved release of the hydrophobic one with 35% in 8 h vs. 5% in the case of the blank sample. This strategy has been proven to influence bijels' properties, opening the doors to many different uses.

Unlocking the Potential of Osmotically Controlled Drug Delivery System: A Comprehensive Review

One of the greatest medication delivery systems available today is osmotically controlled, as it is exceedingly successful and efficient. Osmotic drug delivery devices use the energy-distribution principle of osmotic pressure to deliver medications. Numerous biomedical benefits can be derived from oral osmotic drug delivery systems due to their adaptability and extremely consistent drug release rates. Since osmosis is the transfer from a lower concentration to a higher concentration, osmotic pressure is used in this situation to administer the medication appropriately. This approach allows us to release drugs in an appropriate manner because it is a widely recognized technique with intriguing applications and facts. Like pharmaceuticals, there are different drug delivery components. Each semi-permeable membrane and osmotic agent has a specific function and is necessary. It is one of the best in best method used now a days to get best results.

Competitive coordination assembly of light-degradable gold nanocluster-intercalated metal organic frameworks for photoresponsive drug release.

On-demand controlled drug release holds great promise for cancer therapy. Light-degradable nanocarriers have gained increasing attention for designing controllable drug delivery systems owing to their spatiotemporally controllable properties. Herein, a highly luminescent and light-degradable nanocarrier is constructed by intercalating glutathione-capped gold nanoclusters (AuNCs) into zeolitic imidazolate framework-8 (ZIF-8) via competitive coordination assembly, named AuNC@ZIF-8, for light-triggered drug release. Glutathione-capped AuNCs and 2-methylimidazole (MIm) competitively coordinated with Zn2+ to form AuNC@ZIF-8 using a one step process in an aqueous solution. Specifically, the obtained AuNC@ZIF-8 has a high quantum yield of 52.96% and displays a distinctive property of photolysis. Competitive coordination interactions within AuNC@ZIF-8 were evidenced by X-ray diffraction and X-ray photoelectron spectroscopy, in which Zn2+ strongly coordinated with the N of MIm and weakly coordinated with the carboxyl/amino groups in the glutathione of AuNCs. Under light irradiation, the Au-S bond in AuNCs breaks, enhancing the coordination ability between carboxyl/amino groups and Zn2+. This collapses the crystal structure of AuNC@ZIF-8 and causes subsequent fluorescence quenching. Additionally, AuNC@ZIF-8 is successfully employed as a luminescent nanocarrier of anticancer drugs to form drug-AuNC@ZIF-8, in which three typical anticancer drugs are selected due to different coordination interactions. The obtained smart drug-AuNC@ZIF-8 can be effectively internalized into HeLa cells and degraded in response to blue light, with negligible dark cytotoxicity and high light cytotoxicity. This study highlights the crucial role of competitive coordination interactions in synthesizing functional materials with fluorescence efficiency and photolytic properties.

Carbon dot-modified controllable drug delivery system for sonodynamic/chemotherapy of tumors

Responsive drug delivery nanocapsules based on poly(methacrylic acid)/carbon dots for sonodynamic/chemotherapy of tumors.