Derivatives For Drug Delivery Research Articles

Hydrophilic chitosan: modification pathways and biomedical applications

Chitosan, a natural and abundant polysaccharide, offers several advantageous properties, such as excellent biocompatibility, biodegradability, and antimicrobial activity, making it a highly versatile material. However, its extensive application is hindered by its insolubility in water and most organic solvents, due to numerous intramolecular/intermolecular hydrogen bonds. To overcome this limitation and optimize its benefits, chitosan is often chemically modified to enhance its utility in various industries. Biomedical materials, environmental management, biological papermaking, food preservation, and the daily chemical industry are a few examples. Modified chitosan retains the inherent properties of chitosan and acquires new physicochemical characteristics as a result of introduced functional groups. Hydrophilic modifications typically include carboxylation, phosphorylation, and quaternary ammonium modification reactions. The specific properties and applications of chitosan derivatives depend on the grafted groups. This review summarizes the reaction conditions, properties, and applications of hydrophilic chitosan derivatives in drug delivery and food preservation, serving as a reference for the development and use of chitosan-based biomaterials. <br>The bibliography includes 128 references.

Advances and clinical challenges of mesenchymal stem cell therapy.

In recent years, cell therapy has provided desirable properties for promising new drugs. Mesenchymal stem cells are promising candidates for developing genetic engineering and drug delivery strategies due to their inherent properties, including immune regulation, homing ability and tumor tropism. The therapeutic potential of mesenchymal stem cells is being investigated for cancer therapy, inflammatory and fibrotic diseases, among others. Mesenchymal stem cells are attractive cellular carriers for synthetic nanoparticles for drug delivery due to their inherent homing ability. In this review, we comprehensively discuss the various genetic and non-genetic strategies of mesenchymal stem cells and their derivatives in drug delivery, tumor therapy, immune regulation, tissue regeneration and other fields. In addition, we discuss the current limitations of stem cell therapy and the challenges in clinical translation, aiming to identify important development areas and potential future directions.

Polycaprolactone and its derivatives for drug delivery

AbstractPolycaprolactone (PCL) is polymer of 21st centuries. PCL is a biodegradable and biocompatible polymer used for various healthcare applications. This review explores the properties, synthesis, and processing of PCL. The use of PCL polymer for nanoparticles (NPs), microparticles, films, and fibers offers several advantages for biomedical applications. The review highlights the potential of PCL‐based materials for tissue engineering, drug delivery, wound healing, and implantable medical devices. We also critically analyzed challenges in PCL‐based materials and the strategies used to overcome for successful translation into clinical applications. Overall, this review provides a comprehensive overview of PCL as a valuable biomaterial for healthcare applications.

Application of chitosan and its derivatives in drug delivery

Drug delivery is a method of delivering drug to the patients in a way which increases the concentration of drug to the relevant site by directing the drug to the specific site of action. Polymeric drug delivery systems are mostly preferred to take the drug to the specific site of action and achieve the therapeutic effect. Among different types of biocompatible polymers, carbohydrate-based polymers or polysaccharides are the most common natural polymers with complex structures consisting of long chains of monosaccharide or disaccharide units bound by glycosidic linkages. One such polymer is chitosan which is used in drug delivery. Chitosan’s appealing properties, especially of natural origin, may mediate the protection against degradation of the biologically active substance, control the release of the drug, boost the absorption, increase the physiological action and result in a consequent reduction in the rate of administration. Another advantage of using chitosan is its chemical structure that could be modified easily which makes chitosan derivatives used for different applications. The main objective is to provide an overview on chitosan and its derivatives applications in drug delivery.

The Multifarious Medical Applications of Carbon Curvatures: A Cohort review

Carbon curvatures are novel therapeutic bio-material that are being studied due to its multifarious applications in a variety of research aspects. All the carbon allotropes were grouped mathematically into three types based upon surface Gaussian curvatures: zero curvature (graphene), negative curvature (schwarzites), and positive curvature (fullerenes, CNTs), because they have physiochemical activities, such as optoelectrical, chemical, thermal and magnetic properties. All these allotropes consist of sp2 hybridization with delocalized π bond electrons. Based on the types and number of aromatic carbon rings, all ofthese have unique geometric structural characteristics, chirality, and solubility, which offers them as a potential candidate for biomedical and therapeutic applications. In this short review, we highlight the basic structural and physicochemical characteristics of carbon allotropes and their biomedical and therapeutic applications recentlystudied by researchers and describe the therapeutic applications of graphene and its derivatives in drug delivery, gene delivery, bio-imaging, biosensors, therapeutic diagnosis, and photo-stimulation therapies.

Chitosan Nanoparticles as a Novel Drug Delivery System: A Review Article.

Natural polymers, particularly polysaccharide, have been used as drug delivery systems for a variety of therapeutic agents such as peptides, proteins, vaccines, DNA, and drugs for parenteral and non-parenteral administration. Chitosan, the second most abundant naturally occurring polysaccharide after cellulose, is a biocompatible and biodegradable mucoadhesive polymer that is extensively used in the preparation of nanoparticles (NPs). Chitosan NPs loaded with drugs were found to be stable, permeable and bioactive. In this review, the importance of chitosan and its derivatives in drug delivery is illustrated, different methods of preparation of chitosan and chitosan derivatives NPs and their physio- chemical properties are addressed. Moreover, the desirable characteristics of successful NPs based drug delivery systems, as well as the pharmaceutical applications of these NPs are also clearly explored.

Application of dextran as nanoscale drug carriers.

Dextran is a kind of biocompatible, nontoxic and nonimmunogenic biological substance that has been widely used in drug-delivery systems. With further research and understanding of dextran and its derivatives, people can more precisely control the sequence of dextran by chemical and biosynthetic methods as needed, and modify various structures to improve the properties of dextran, such as hydrophilicity, hydrophobicity, temperature sensitivity, pH sensitivity and ionic strength sensitivity, which will further expand the application of dextran and its derivatives in drug-delivery systems. Herein, the application of dextran and its derivatives in gene transfection and drug delivery was summarized and analyzed, and the problems were studied. At the same time, its application prospects are forecasted.

Novel biodegradable hydrogels based on pachyman and its derivatives for drug delivery

Two kinds of hydrogels were synthesized based on pachyman and its hydroxyethyl derivatives (hydroxyethyl pachyman, HEP) by the crosslinking reactions with confunctional crosslinker agent epichlorohydrin (ECH). Hydrogels with different crosslinking ratio were obtained by varying the content of the crosslinker and the polymer. The structure and morphology of hydrogels were characterized and the pH-dependent swelling of hydrogels was confirmed to be strongly influenced by the polymer properties, structure and the crosslinker contents. In the swelling assays, the hydrogels based on pachyman exhibited significant pH sensitivity, while the hydrogels based on hydroxyethyl pachyman tended to have notable swelling capability. In the drug release study, two drugs salicylic acid and bovine serum albumin (BSA) were chosen as model drugs. The results indicated that both two kinds of hydrogels showed better drug sustained release behavior for protein drug BSA than salicylic acid. In addition, evaluated by two model equations, the drug transport mechanism showed anomalous in both two kinds of hydrogels. Importantly, this study offers an entirely new window of developing hydrogels based on this natural polysaccharide, which has great potential for using as a novel sustained release carrier for protein drugs.

Succinoylated Poly[N-(2- Hydroxyethyl)-L-Glutamine] Derivatives for Drug Delivery

A series of succinoylated poly[N-(2-)- L-glutamine] (PHEG) derivatives was synthesized by reacting PHEG with succinic anhydride in the presence of N,N-dimethylaminopyridine as a catalyst. The size of the derivatives were measured by dynamic light scattering in buffers (pH 5.5 and 7.4, respectively) the lysosomal and physiological pH. The degradability of the succinoylated polymers toward cathepsin B was followed by gel permeation chromatography. It was demonstrated that an increase of modification results in decreased biodegradability. Conjugation of mitomycin C (MMC) with a succinoylated PHEG derivative through a collagenase-sensitive Pro-Leu-Gly-Pro- Leu spacer resulted in a water-soluble MMC conjugate. This conjugate was shown to be hydrolytically stable in buffers of lysosomal and physiological pH and able to release MMC in the presence of the bacterial collagenase clostridium histolyticum.

Pharmacokinetic Analysis of 6-Monoamino-β-Cyclodextrin after Intravenous or Oral Administration to Rats using a Specific Enzyme Immunoassay

We have developed a highly sensitive enzyme immunoassay for 6-monoamino-β-CD (mono(6-amino-6-deoxy)cyclomalto-heptaose) and its parent compound (β-CD) with a detection limit in the 100 pg/mL range. The polyclonal antibodies obtained are highly specific for the β-cyclodextrin core and do not recognize other cyclic cyclodextrins (i.e., α- and γ-CD) or linear analogues. This enzyme immunoassay can be used to quantify 6-monoamino-β-CD in rat urine and plasma. Using this immunoassay, we have evaluated the main pharmacokinetic parameters of 6-monoamino-β-CD after iv administration to the rat of a 25 mg/kg dose. Since this method is strictly specific to the native β-CD form, we have demonstrated that the molecule rapidly disappeared from plasma but is probably distributed in the tissues. The urinary route appears as the predominant way of elimination since almost all the administered drug is recovered in urine. Finally, analysis of the same molecule after oral administration to the rat (25 mg/kg) demonstrates low plasma levels and that about 1% of the administered dose is excreted in urine. These experiments demonstrate the high stability of the β-CD core irrespective of the method of administration. This immunological method could provide relevant information on the fate of β-CD and some derivatives for drug delivery using different modes of administration (oral, parenteral, transmucosal, or dermal).

Hyaluronate Derivatives in Drug Delivery

Hyaluronan (HA), an abundant nonsulfated glycosaminoglycan component of synovial fluid and the extracellular matrix, is an attractive building block for new biocompatible and biodegradable polymers that have applications in drug delivery, tissue engineering, and viscosupplementation. This review consists of three subtopics: (i) chemical modification of HA; (ii) physicochemical and biochemical characterization of HA derivatives; and (iii) in vitro and in vivo bioevaluation studies. Important new products have already reached the marketplace, and the approval and introduction of a variety of new medical applications of HA-based biomaterials can be anticipated in the next decade.