Modified Carboxymethyl Chitosan Research Articles

Static and dynamic adsorption of arsenate from water by Fe3+ complexed with 3-aminopropyltriethoxysilane-modified carboxymethyl chitosan.

Fe3+ complexed with 3-aminopropyltriethoxysilane (APTES)-modified carboxymethyl chitosan (CMC) named Fe-ACMC was synthesized by a one-step method at room temperature and pressure. The surface morphology and chemical structure of Fe-ACMC were characterized by SEM-EDS, XRD, BET, FT-IR, XPS, and ζ-potential. In batch adsorption, the optimum pH for arsenate [As(V)] adsorption onto Fe-ACMC was 3-9 with removal efficiency > 99%. The adsorption of As(V) could reach equilibrium within 25min and the maximum adsorption capacity was 84.18mgg-1. The pseudo-second-order model fitted well the kinetic data (R2 = 0.995), while the Freundlich model well described the adsorption isotherm of As(V) on Fe-ACMC (R2 = 0.979). The co-existing anions (NO3-, CO32-, and SO42-) exhibited a slight impact on the As(V) adsorption efficiency, whereas PO43- inhibited As(V) adsorption on Fe-ACMC. The real applicability of Fe-ACMC was achieved to remove ca. 10.0mg L-1 of As(V) from natural waters to below 0.05mg L-1. The regeneration and reuse of Fe-ACMC for As(V) adsorption were achieved by adding 0.2mol L-1 HCl. The main adsorption mechanism of As(V) on Fe-ACMC was attributed to electrostatic attraction and inner-sphere complexation between -NH2···Fe3+ and As(V). In fixed-bed column adsorption, the Thomas model was the most suitable model to elucidate the dynamic adsorption behavior of As(V). The loading capacity of the Fe-ACMC packed column for As(V) was 47.04mgg-1 at pH 7 with an initial concentration of 60mg L-1, flow rate of 3mLmin-1, and bed height of 0.6cm.

A double‐dynamic‐bond crosslinked multifunctional conductive hydrogel with self‐adhesive, remoldability, and rapid self‐healing properties for wearable sensing

AbstractIn recent years, conductive hydrogels have been designed as flexible sensors with broad application prospects in the field of smart wearable devices. However, the coordination of the mechanical properties, self‐healing capability, and conductivity of hydrogels has always been a challenge. In this work, a multifunctional conductive hydrogel with self‐adhesive, re‐shapeable, and rapid self‐healing abilities (PB‐PACS‐PM3 (self‐healing efficiency) = 98.8% in 15 s) was prepared by incorporating protocatechualdehyde modified carboxymethyl chitosan (PA@o‐CMCS) and PDA‐modified MXene (PDA@MXene) into the interchain of polyvinyl alcohol through dynamic borate ester crosslinking. The dynamic Schiff base reaction not only effectively introduced o‐CMCS as a mechanical enhancer but also improved the viscoelasticity and self‐healing capability of the hydrogel through the dual dynamic bond crosslinking structure. The PDA@MXene nanosheets are uniformly distributed in the hydrogel, providing the composite system with excellent conductivity (the conductivity of PB‐PACS‐PM3 hydrogel is 1.5 S/m) and strain sensitivity (the response time and recovery time of the hydrogel sensor are 230 and 260 ms, respectively), while the tensile strength of the hydrogel is improved to 0.035 MPa. Due to all these advantages, this conductive hydrogel can be assembled into flexible wearable sensors for rapid and accurate monitoring of various physiological activities of the human body, such as finger, wrist, elbow, and knee bending vibrations, among others.

A self-fused hydrogel for the treatment of glottic insufficiency through outstanding durability, extracellular matrix-inducing bioactivity and function preservation.

Injection laryngoplasty with biomaterials is an effective technique to treat glottic insufficiency. However, the inadequate durability, deficient pro-secretion of extracellular matrix (ECM) and poor functional preservation of current biomaterials have yielded an unsatisfactory therapeutic effect. Herein, a self-fusing bioactive hydrogel comprising modified carboxymethyl chitosan and sodium alginate is developed through a dual-crosslinking mechanism (photo-triggered and dynamic covalent bonds). Owing to its characteristic networks, the synergistic effect of the hydrogel for vocal folds (VFs) vibration and phonation is adequately demonstrated. Notably, owing to its inherent bioactivity of polysaccharides, the hydrogel could significantly enhance the secretion of major components (type I/III collagen and elastin) in the lamina propria of the VFs both in vivo and in vitro. In a rabbit model for glottic insufficiency, the optimized hydrogel (C1A1) has demonstrated a durability far superior to that of the commercially made hyaluronic acid (HA) Gel. More importantly, owing to the ECM-inducing bioactivity, the physiological functions of the VFs treated with the C1A1 hydrogel also outperformed that of the HA Gel, and were similar to those of the normal VFs. Taken together, through a simple-yet-effective strategy, the novel hydrogel has demonstrated outstanding durability, ECM-inducing bioactivity and physiological function preservation, therefore has an appealing clinical value for treating glottic insufficiency.

A multi-crosslinking strategy of organic and inorganic compound bio-adhesive polysaccharide-based hydrogel for wound hemostasis

Polysaccharides are naturally occurring polymers with exceptional biodegradable and biocompatible qualities that are used as hemostatic agents. In this study, photoinduced CC bond network and dynamic bond network binding was used to give polysaccharide-based hydrogels the requisite mechanical strength and tissue adhesion. The designed hydrogel was composed of modified carboxymethyl chitosan (CMCS-MA) and oxidized dextran (OD), and introduced hydrogen bond network through tannic acid (TA) doping. Halloysite nanotubes (HNTs) were also added, and the effects of various doping amount on the performance of the hydrogel were examined, in order to enhance the hemostatic property of hydrogel. Experiments on vitro degradation and swelling demonstrated the strong structural stability of hydrogels. The hydrogel has improved tissue adhesion strength, with a maximum adhesion strength of 157.9 kPa, and demonstrated improved compressive strength, with a maximum compressive strength of 80.9 kPa. Meanwhile, the hydrogel had a low hemolysis rate and had no inhibition on cell proliferation. The created hydrogel exhibited a significant aggregation effect on platelets and a reduced blood clotting index (BCI). Importantly, the hydrogel can quickly adhere to seal the wound and has good hemostatic effect in vivo. Our work successfully prepared a polysaccharide-based bio-adhesive hydrogel dressing with stable structure, appropriate mechanical strength, and good hemostatic properties.

Self-Healing Hydrogels Fabricated by Introducing Antibacterial Long-Chain Alkyl Quaternary Ammonium Salt into Marine-Derived Polysaccharides for Wound Healing

The development of hydrogels as wound dressings has gained considerable attention due to their promising ability to promote wound healing. However, in many cases of clinical relevance, repeated bacterial infection, which might obstruct wound healing, usually occurs due to the lack of antibacterial properties of these hydrogels. In this study, we fabricated a new class of self-healing hydrogel with enhanced antibacterial properties based on dodecyl quaternary ammonium salt (Q12)-modified carboxymethyl chitosan (Q12-CMC), aldehyde group- modified sodium alginate (ASA), Fe3+ via Schiff bases and coordination bonds (QAF hydrogels). The dynamic Schiff bases and coordination interactions conferred excellent self-healing abilities to the hydrogels, while the incorporation of dodecyl quaternary ammonium salt gave the hydrogels superior antibacterial properties. Additionally, the hydrogels displayed ideal hemocompatibility and cytocompatibility, crucial for wound healing. Our full-thickness skin wound studies demonstrated that QAF hydrogels could result in rapid wound healing with reduced inflammatory response, increased collagen disposition and improved vascularization. We anticipate that the proposed hydrogels, possessing both antibacterial and self-healing properties, will emerge as a highly desirable material for skin wound repair.

Efficiency of a novel thermosensitive enema in situ hydrogel carrying Periplaneta americana extracts for the treatment of ulcerative colitis.

Objective: The aim of this study was to develop a thermosensitive in situ gel (TISG) as an effective rectal delivery platform for delivering Periplaneta americana extracts (PA) to alleviate ulcerative colitis (UC) and explore the underlying molecular mechanism. Materials and methods: Thermosensitive (poloxamer 407) and adhesive polymers (chondroitin sulfate modified carboxymethyl chitosan, CCMTS) were used to construct the in situ gel. CCMTS and aldehyde poloxamer 407 (P407-CHO) were synthesized and chemically cross-linked by Schiff base reaction to formulate thermosensitive in situ gel, which carried Periplaneta americana extracts (PA/CCMTS-P). The cytotoxicity and cellular uptake of CCMTS-P were investigated in lipopolysaccharide (LPS) -induced macrophages by CCK-8 assay. The anti-inflammatory effects of PA/CCMTS-P were studied in lipopolysaccharide-induced RAW264.7 cells and dextran sulfate sodium (DSS)-induced ulcerative colitis mouse models. In addition, the ability of PA/CCMTS-P to restore the intestinal mucosal barrier after rectal administration was evaluated by immunohistochemical analysis (IHC). Results: PA/CCMTS-P was prepared and characterized as gel with a phase-transition temperature of 32.9°C. The results of the in vitro experiments indicated that the hydrogels promoted the cellular uptake of Periplaneta americana extracts without causing any toxicity as compared to the free gel. PA/CCMTS-P showed superior anti-inflammatory activity both in vitro and in vivo, which restored the damaged intestinal mucosal barrier associated by inhibiting necroptosis in dextran sulfate sodium-induced ulcerative colitis models. Conclusion: The findings from our study show that the rectal administration of PA/CCMTS-P holds a promising potential for the treatment of ulcerative colitis.

Enhanced Colon-Targeted Release of Propolis by pH-driven Encapsulation using Folic Acid Modified Carboxymethyl Chitosan

Enhanced Colon-Targeted Release of Propolis by pH-driven Encapsulation using Folic Acid Modified Carboxymethyl Chitosan

Multi-crosslinking hydrogels with robust bio-adhesion and pro-coagulant activity for first-aid hemostasis and infected wound healing

Bio-adhesive polysaccharide-based hydrogels have attracted much attention in first-aid hemostasis and wound healing for excellent biocompatibility, antibacterial property and pro-healing bioactivity. Yet, the inadequate mechanical properties and bio-adhesion limit their applications. Herein, based on dynamic covalent bonds, photo-triggered covalent bonds and hydrogen bonds, multifunctional bio-adhesive hydrogels comprising modified carboxymethyl chitosan, modified sodium alginate and tannic acid are developed. Multi-crosslinking strategy endows hydrogels with improved strength and flexibility simultaneously. Owing to cohesion enhancement strategy and self-healing ability, considerable bio-adhesion is presented by the hydrogel with a maximal adhesion strength of 162.6 kPa, 12.3-fold that of commercial fibrin glue. Based on bio-adhesion and pro-coagulant activity (e.g., the stimulative aggregation and adhesion of erythrocytes and platelets), the hydrogel reveals superior hemostatic performance in rabbit liver injury model with blood loss of 0.32 g, only 54.2% of that in fibrin glue. The healing efficiency of hydrogel for infected wounds is markedly better than commercial EGF Gel and Ag+ Gel due to the enhanced antibacterial and antioxidant properties. Through the multi-crosslinking strategy, the hydrogels show enhanced mechanical properties, fabulous bio-adhesion, superior hemostatic performance and promoting healing ability, thereby have an appealing application value for the first-aid hemostasis and infected wound healing.

MMP‐2 Responsive Unidirectional Hydrogel‐Electrospun Patch Loading TGF‐β1 siRNA Polyplexes for Peritendinous Anti‐Adhesion

AbstractBio‐derived hydrogel patch systems exhibit promising potential in localized drug delivery for the prevention and treatment of various diseases. However, the uncontrolled release from the hydrogel patch both in time and space, is not an optimal strategy for peritendinous anti‐adhesion, leading to transient effect and unnecessary diffusion of therapeutics. Here, an innovative composite anti‐adhesion patch is designed for on‐demand and unidirectional polyplexes delivery to inhibit fibroblasts proliferation and collagen deposition by silencing fibrosis gene transforming growth factor‐β1 (TGF‐β1). Firstly, a metalloproteinase‐2 (MMP‐2) degradable hydrogel is prepared by crosslinking allyl glycidyl ether (AGE) modified carboxymethyl chitosan (CMCS‐AGE) with MMP‐2 substrate peptide CPLGLAGC (MMP‐2 sp). Then, the hydrogel loading TGF‐β1 siRNA polyplexes are attached onto polycaprolactone (PCL) electrospun fibers to form a composite bilayer patch. The hydrogel–electrospun fibers (H–E) patch shows MMP‐2‐responsive and unidirectional release behaviors of encapsulated TGF‐β1 siRNA polyplexes and associated gene silencing effect on TGF‐β1, leading to the inhibition of fibroblasts proliferation. Moreover, after implanting the H–E patch by wrapping the repaired tendon, the formation of adhesion tissue is responsively attenuated in MMP‐2 overexpression microenvironment. This study presents a promising approach employing a composite bilayer patch with on‐demand and unidirectional delivery strategy for peritendinous anti‐adhesion.

Liquid Bandage Harvests Robust Adhesive, Hemostatic, and Antibacterial Performances as a First‐Aid Tissue Adhesive

AbstractMassive bleeding and wound infection after tissue trauma are the major dangerous factors of casualties in disasters; hence, first‐aid supplies that can greatly achieve wound closure and effectively control the hemorrhage and infection are urgently needed. Although existing tissue adhesives can adhere to the tissue surfaces and achieve rapid wound closure, most of them have limited hemostatic and antibacterial capacities, making them unsuitable as the first‐aid tissue adhesives. In this study, inspired by the inherent hemostatic and antibacterial capacities of chitosan and the excellent tissue integration capacity originating from a Schiff base reaction, liquid bandage (LBA), an in situ imine crosslinking‐based photoresponsive chitosan hydrogel (NB‐CMC/CMC hydrogel), is developed for emergency wound management. Upon UV irradiation, o‐nitrobenzene in modified carboxymethyl chitosan (CMC) converts to o‐nitrosobenzaldehyde that subsequently crosslinks with amino groups on tissue surface, which endows the LBA with superior tissue adhesive performance. LBA's hemostatic and antibacterial properties can be tuned by the mass ratio of NB‐CMC/CMC. Moreover, it exhibits satisfactory biocompatibility, biodegradability, and the capability to enhance wound healing process. This study sheds new light on the development of a multifunctional hydrogel‐based first‐aid tissue adhesive that can achieve robust tissue adhesion, effectively control bleeding, prevent bacterial infection, and promote wound healing.

Polymeric micelles based on amphiphilic oleic acid modified carboxymethyl chitosan for oral drug delivery of bcs class iv compound: Intestinal permeability and pharmacokinetic evaluation

Chemical modification of chitosan derivatives with hydrophobic fatty acids to enhance their self-aggregation behavior is well established. Previously our group reported low molecular weight carboxymethyl chitosan (CMCS) which showed enhancement in apparent permeability of hydrophobic drug, tamoxifen. Further extension to this work, herein we synthesize a new polymer of oleic acid grafted low molecular weight carboxymethyl chitosan (OA-CMCS) for maneuvering biopharmaceutical performance of poorly water soluble drugs. This polymer was designed and synthesized via amidation reaction and well characterized by analytical tools like 1H-NMR and FT-IR spectroscopy. OA-CMCS conjugate easily self-organized into micelles like structure in an aqueous medium and showed a low critical micellar concentration of 1 µg/mL. Poorly water-soluble drug, docetaxel (DTX) was used as a model drug in this study. Optimization of variables resulted in the formation of spherical DTX loaded OA-CMCS micelles in the size range of 213.4 ± 9.6 nm with an entrapment efficiency of 57.26 ± 1.25%. DTX loaded OA-CMCS micelles showed slow and sustained DTX release behavior in simulated body fluid during in vitro release study. The permeability of DTX loaded OA-CMCS micelles across the gastrointestinal tract were investigated by in vitro Caco-2 cells model. The apparent permeability of DTX loaded OA-CMCS micelles improved up to 6.57-fold in comparison to free DTX suspension which indicates the increase in paracellular absorption of DTX. Additionally, in vivo pharmacokinetic study demonstrates an increase in Cmax (1.97-fold) and AUC (2.62-fold) for DTX loaded OA-CMCS micelles compared to free DTX suspension. Hence, we propose OA-CMCS as a promising cargo to incorporate drugs for enhancement of biopharmaceutical performance.

Aplikasi Chitosan Modified Carboxymethyl sebagai Coating Agent dalam Perbaikan Mutu Kertas

This study aimed to determine the effect of coating paper with Modified Carboxymethyl Chitosan (Cs-Mcm) to improve the quality of the paper, including paper grammage, tensile strength of paper, torn paper and a strong degree of fineness of the paper. The study was conducted by superimposing the Cs-Mcm as a coating agent on a paper-based pulp rice straw pulp waste paper and pulp mixture (rice straw and waste paper) with various concentration of acetic acid solvent 2%, 3%, 5% and 7%. The analysis showed the concentration of acetic acid solvent effect on the quality of recycled paper. Coating with Cs-Mcm in this study can improve the quality of recycled paper.

Self‐Healing, High Adherent, and Antioxidative LbL Multilayered Film for Enhanced Cell Adhesion

AbstractCell adhesion acts as a complex process that is hardly promoted through surfaces with a single performance. Controlling the cell's adhesion on the interfaces between the synthetic materials and the biological environments remains a real challenge in the biomedical fields. Herein, based on RGD peptide modified carboxymethyl chitosan (CCS‐R) and dopamine modified oxidized alginate (OALG‐D), a layer‐by‐layer (LbL) self‐assemble multilayered (CCS‐R/OALG‐D)15 film is developed. The multifunctional (CCS‐R/OALG‐D)15 film with a self‐healing, highly adherent, biocompatible, and antioxidative biomatrix property for the cell adhesion is fabricated with the Schiff‐base bond, electrovalent bond, and hydrogen bond. The LbL multilayered film exhibits the significant cell adhesion ability for the normal human dermal fibroblast cells and the coral Acropopa formosa cells. Furthermore, it holds high self‐healing efficiency (88.8%), excellent adhesion strength (adhesive stress: 61.1 MPa), and outstanding antioxidation (free radical scavenging rate: 86.8%). Furthermore, it is demonstrated that the LbL multifunctional film, as a culture matrix, has prolonged the survival of the coral Acropopa formosa. Therefore, the incorporation of a self‐healing, high adhesion, superior cell adhesion, and antioxidation property into a single LbL self‐assembly film provides a promising platform for regenerative medicine.

Moist-Retaining, Self-Recoverable, Bioadhesive, and Transparent in Situ Forming Hydrogels To Accelerate Wound Healing.

In the management of accelerating wound healing, moist environments play an important role. Compared with other scaffolds of various forms, hydrogels can maintain a moist environment in the wound area. They are cross-linked hydrophilic polymeric networks that resemble natural soft tissues and extracellular matrices. Among them, injectable hydrogels have attracted great attention in wound repair, as they can be injected into irregular-shaped skin defects and formed in situ to shape the contour of different dimensions. The excellent compliance makes hydrogels easy to adapt to the wound under different conditions of skin movement. Here, we oxidized hydroxyethyl starch (O-HES) and modified carboxymethyl chitosan (M-CMCS) to fabricate an in situ forming hydrogel with excellent self-recoverable extensibility-compressibility, biocompatibility, biodegradability, and transparency for accelerating wound healing. The oxidation degree of O-HES was 74%. The amino modification degree of M-CMCS was 63%. M-CMCS/O-HES hydrogels were formed through the Schiff base reaction. The physicochemical properties of M-CMCS/O-HES hydrogels with various ratios were investigated, and M-CMCS/O-HES hydrogel with a volume ratio of 5:5 exhibited appropriate gelation time, notable water-retaining capacity, self-recoverable conformal deformation, suitable biodegradability, and good biocompatibility for wound-healing application. Then, skin wound-healing experimental studies were carried out in Sprague-Dawley rats with full-thickness skin defects. Significant outcomes were achieved in the M-CMCS/O-HES hydrogel-treated group including higher wound closure percentage, more granulation tissue formation, faster epithelialization, and decreased collagen deposition. These findings demonstrate that using the obtained M-CMCS/O-HES hydrogels is a promising therapeutic strategy for wound healing.

Cytocompatible quaternized carboxymethyl chitosan/poly(vinyl alcohol) blend film loaded copper for antibacterial application

Antibacterial quaternized carboxymethyl chitosan/poly(vinyl alcohol)/Cu blend film (QCMCS/PVA/Cu blend film) was prepared by quaternary ammonium salt modified carboxymethyl chitosan (QCMCS), PVA and copper sulfate pentahydrate via the process of solution casting and ion adsorption. The successful preparation of QCMCS was proved by EA, NMR and FTIR, and the degree of quaternization is 71.86%. The QCMCS/PVA/Cu blend film was characterized by SEM, AFM and EDX, and the content of the copper is about 1 wt%. Tensile tests and TGA showed that the mechanical and thermal properties were improved after being loaded with copper ions. By loading with Cu2+, the blend film showed good antibacterial activities. About 98.3% of S. aureus and 99.9% of E. coli could be inactivated within 60 min. The cell cytotoxicity was also studied and the results showed that all the prepared films had acceptable cell viability and biocompatible, which indicates that this blend film has potential applications in packaging and biomedical materials.

Carboxymethyl Chitosan and Its Hydrophobically Modified Derivative as pH-Switchable Emulsifiers.

The emulsification properties of carboxymethyl chitosan (CMChi) and hydrophobically modified carboxymethyl chitosan (h-CMChi) were studied as a function of pH and dodecane/water ratio. The pH was varied between 6—10, and the oil/water ratio between 0.1—2.0. In CMChi solution, the emulsion stability increased as the pH was lowered from 10 to 7, and the phase inversion was shifted from oil/water ratio 1.0 to 1.8, respectively. The system behaved differently in pH 6 due to the aggregation of CMChi and the formation of nanoparticles (∼200—300 nm). No phase inversion was observed and the maximum amount of emulsified oil was reached at oil/water ratio 1.2. The h-CMChi showed similar behavior as a function of pH but, due to hydrophobic modification, the phase inversion was shifted to higher values in pH 7—10. In pH 6, the behavior was similar, but the maximum amount of emulsified oil was higher compared to CMChi. The amount of adsorbed particles correlated with the emulsified amount of oil. Reversible emulsification of dodecane was demonstrated by pH adjustment using CMChi and h-CMChi solutions. The formed emulsions were gel-like, suggesting particle–particle interaction.

改性羧甲基壳聚糖复合材料的制备、表征与研究

改性羧甲基壳聚糖复合材料的制备、表征与研究

Preparation and evaluation of insulin-loaded nanoparticles based on hydroxypropyl-β-cyclodextrin modified carboxymethyl chitosan for oral delivery

Novel insulin-loaded nanoparticles based on hydroxypropyl-β-cyclodextrin modified carboxymethyl chitosan (CMC-HP-β-CD) were prepared to improve the oral bioavailability of insulin. The CMC-HP-β-CD was characterized by FT-IR spectroscopy and 1H-NMR spectra. The insulin-loaded nanoparticles were prepared through crosslinking with calcium ions, and the morphology and size of the prepared nanoparticles were characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS). Cumulative release in vitro study was performed respectively in simulated gastric medium fluid (SGF, pH=1.2), simulated intestinal fluid (SIF, pH=6.8) and simulated colonic fluid (SCF, pH=7.4). The encapsulation efficiency of insulin was up to 87.14 ± 4.32% through high-performance liquid chromatography (HPLC). Statistics indicated that only 15% of the encapsulated insulin was released from the CMC-HP-β-CD nanoparticles in 36 h in SGF, and about 50% of the insulin could be released from the nanoparticles in SIF, whereas more than 80% was released in SCF. In addition, the solution containing insulin nanoparticles could effectively reduce the blood glucose level of diabetic mice. The cytotoxicity test showed that the samples had no cytotoxicity. CMC-HP-β-CD nanoparticles are promising candidates as potential carriers in oral insulin delivery systems.

Preparation and Properties Characterization of Modified Chitosan Composited Hemostatic Materials

Carboxymethyl chitosan (CAS) was obtained by carboxymethylation of chitosan (CS).The Ag+-CAS,TiO2-CAS and Ag+-TiO2-CAS were prepared by introducing AgNO3 and nanometre TiO2 solution into the product obtained the previous step. The structures of samples were characterized by IR, XRD, SEM etc. The properties of cruor and hemostasis were studied by biological experiment. The results showed that there were characteristic absorption peaks of carboxymethyl chitosan sodium salt around 3423cm-1 and 1380cm-1 in the IR spectra of modified carboxymethyl chitosan. The XRD showed it was metals Crystalline. The average diameter of CAS was about 14.8nm, the Ag+ was 143.5nm, nanometre TiO2 was 267.2nm and all of them were homodisperse. The properties of crour and hemostasis of Ag+-TiO2-CAS were superior to Ag+-CAS and TiO2-CAS, while the Ag+-CAS and TiO2-CAS were also have an advantage over CAS.

Self-assembled nanoparticles based on folic acid modified carboxymethyl chitosan conjugated with targeting antibody

Nanoparticles conjugated with antibody were designed as active drug delivery system to reduce the toxicity and side effects of drugs for acute myeloid leukemia (AML). Moreover, methotrexate (MTX) was chosen as model drug and encapsulate within folic acid modified carboxymethyl chitosan (FA-CMCS) nanoparticles through self-assembling. The chemical structure, morphology, release and targeting of nanoparticles were characterized by routine detection. It is demonstrated that the mean diameter is about 150 nm, the release rate increases with the decreasing of pH, the binding rate of CD33 antibody and FA-CMCS nanoparticles is about 5:2, and nanoparticles can effectively bind onto HL60 cells in vitro. The experimental results indicate that the FA-CMCS nanoparticles conjugated with antibody may be used as a potential pHsensitive drug delivery system with leukemic targeting properties.