Novel collagen scaffolds prepared by using unnatural D-amino acids assisted EDC/NHS crosslinking.

This work discusses the preparation and characterization of novel collagen scaffolds by using unnatural D-amino acids (Coll-D-AAs)-assisted 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC)/N-hydroxyl succinimide(NHS)-initiated crosslinking. The mechanical strength, hydrothermal and structural stability, resistance to biodegradation and the biocompatibility of Coll-D-AAs matrices were investigated. The results from Thermo mechanical analysis, Differential scanning calorimetric analysis and Thermo gravimetric analysis of the Coll-D-AAs matrices indicate a significant increase in the tensile strength (TS, 180±3), % elongation (% E, 80±9), elastic modulus (E, 170±4) denaturation temperature (T d, 108±4) and a significant decrease in decomposition rate (Tg, 64±6).

Preparation and properties of tannic acid cross-linked collagen scaffold and its application in wound healing.

A biodurable porous scaffold of collagen with good biocompatibility and enhanced wound healing potential is prepared through casting technique using tannic acid (TA) as crosslinker. The morphological analysis of the tannic acid cross-linked collagen scaffold (TCCs) distinctively shows scaly interlinks with large pores. The enzymatic stability of the scaffold is characterized in vitro to detail the role of TA in stabilization of collagen matrix against collagenolytic degradation.

Development of D-lysine-assisted 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide/N-hydroxysuccinimide-initiated cross linking of collagen matrix for design of scaffold.

This work discusses the preparation and characterization of collagen scaffold with presence of D-Lysine (Coll-D-Lys)-assisted 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC)/N-hydroxysuccinimide (NHS)-initiated cross linking. The mechanical strength, thermal and structural stability, resistance to biodegradation and cell viability of this scaffold was investigated. The results of the Coll-D-Lys-EDC/NHS scaffold also indicate an increase in the tensile strength (T(S)), percentage of elongation (% E), denaturation temperature (T(d)), and decrease the decomposition rate.

Comparative evaluation of a bioabsorbable collagen membrane and connective tissue graft in the treatment of localized gingival recession: A clinical study.

Background: Gingival recession (GR) can result in root sensitivity, esthetic concern to the patient, and predilection to root caries. The purpose of this randomized clinical study was to evaluate (1) the effect of guided tissue regeneration (GTR) procedure using a bioabsorbable collagen membrane, in comparison to autogenous subepithelial connective tissue graft (SCTG) for root coverage in localized gingival recession defects; and (2) the change in width of keratinized gingiva following these two procedures.

Materials And Methods: A total of 10 cases, showing at least two localized Miller's Class I or Class II gingival recession, participated in this study.

Studies on collagen-tannic acid-collagenase ternary system: Inhibition of collagenase against collagenolytic degradation of extracellular matrix component of collagen.

We report the detailed studies on the inhibitory effect of tannic acid (TA) on Clostridium histolyticum collagenase (ChC) activity against degradation of extracellular matrix component of collagen. The TA treated collagen exhibited 64% resistance against collagenolytic hydrolysis by ChC, whereas direct interaction of TA with ChC exhibited 99% inhibition against degradation of collagen and the inhibition was found to be concentration dependant. The kinetic inhibition of ChC has been deduced from the extent of hydrolysis of N-[3-(2-furyl) acryloyl]-Leu-Gly-Pro-Ala (FALGPA).

Protective effect of Withania somnifera and Cardiospermum halicacabum extracts against collagenolytic degradation of collagen.

The irreversible destruction of extracellular matrix (ECM) such as cartilage, tendon, and bone that comprise synovial joints is the hallmark of both rheumatoid arthritis and osteoarthritis by over-expression of matrix metalloproteinase (MMP)-collagenases. We report herein the detailed study on the inhibitory effects of Withania somnifera extract (WSE) and Cardiospermum halicacabum extract (CHE) on Clostridium histolyticum collagenase (ChC) activity against the degradation of the ECM component of bovine Achilles tendon type I collagen by hydroxyproline assay method. Interaction of WSE and CHE with ChC exhibited 71% and 88% inhibition, respectively, to the collagenolytic activity of ChC against collagen degradation, and the inhibition was found to be concentration-dependent.

Formulation and evaluation of quercetin polycaprolactone microspheres for the treatment of rheumatoid arthritis.

Quercetin had been shown to be effective in the management of arthritis. However, bioavailability of quercetin is a concern for such treatment. This work aims at the development of intra-articular drug delivery system by controlled release of quercetin (loaded in microspheres) for the management of rheumatoid arthritis.

Characterization of biocompatible collagen fibers--a promising candidate for cardiac patch.

Type I and III collagens form the natural framework of the heart, and decellularized heart tissue revealed a fine weave of three dimensionally arranged collagen fibers. To mimic this structure for the fabrication of a cardiac patch, a process has been devised to extract solid atelopeptide collagen from bovine tendon while preserving its inherent tensile properties. Unlike chemical/enzymatic methods, which involve cellular disruption or reconstitution, this microbial collagen extraction process helps to get pure collagen fibers with their native properties intact.

Porous keratin scaffold-promising biomaterial for tissue engineering and drug delivery.

A porous keratin scaffold, prepared from the reduced keratin solution, has shown good cell viability which makes it a potential candidate for cell seeding. An aqueous solution of reduced keratin was extracted from horn meal using a mixture of urea, sodium dodecyl sulfate, mercaptoethanol, and water at 60 degrees C. The molecular mass of the extracted keratin is found to be ranging between 225 and 150 KDa.

Collagen-coated microparticles in drug delivery.

Advantages of drug-incorporated collagen particles have been described for the controlled delivery system for therapeutic actions. The attractiveness of collagen lies in its low immunogenicity and high biocompatibility. It is also recognized by the body as a natural constituent rather than a foreign body.

Triphala incorporated collagen sponge--a smart biomaterial for infected dermal wound healing.

Background: Wound infection is a major problem in the medical community since many types of wounds are more prone to microbial contamination leading to infection. Triphala (a traditional ayurvedic herbal formulation) incorporated collagen sponge was investigated for its healing potential on infected dermal wound in albino rats.

Materials And Methods: Methanol extract of triphala was prepared and analyzed for the presence of catechin by high-pressure liquid chromatography analysis.

Collagen-coated polycaprolactone microparticles as a controlled drug delivery system.

Objective: Polycaprolactone (PCL) microparticles coated with acetylated collagen have been assessed for use as a controlled drug delivery system.

Method: The surface morphology, drug encapsulation and release profile of PCL microparticles and collagen-coated PCL microparticles containing doxycycline hydrochloride (DH) have been investigated in order to develop a controlled release system which would in addition act as a scaffold for cell attachment. PCL microparticles were prepared by emulsion solvent evaporation technique and loaded with DH.

Triphala promotes healing of infected full-thickness dermal wound.

Background: Infection is a major problem in the management of wounds. Even though the development of synthetic antimicrobial agents persists, drug resistance and toxicity hinder their way. Many plants with multi-potent pharmaceutical activities may offer better treatment options, and Triphala (dried fruits of Terminalia chebula, Terminalia bellirica, and Phyllanthus emblica) are potential formulations evaluated for healing activity on infected wound as it possesses numerous activities.

Collagen bilayer dressing with ciprofloxacin, an effective system for infected wound healing.

Bacterial wound infection is a major problem, which hinders the normal healing process. In this study, a collagen bilayer dressing with ciprofloxacin was prepared from succinylated type-I collagen; FT-IR spectroscopy, SEM analysis, in vitro drug release pattern, antimicrobial activity and in vivo efficacy of the dressing were studied. The healing pattern was analyzed on days 3, 5, 7, 14 and 21 by wound healing rate, bacterial population, biochemical and histological examinations of tissue samples.

Expression of matrix metalloproteinases (MMP-8 and -9) in chronic periodontitis patients with and without diabetes mellitus.

Background: Matrix metalloproteinases (MMPs) are involved in a number of physiological events, and they are the major players in collagen breakdown during periodontal tissue destruction. Diabetes mellitus (DM) has been associated with altered collagen metabolism and increases the response of the periodontal tissue to pathogenic microorganisms, thereby increasing the severity of periodontal disease. The aim of this study was to assess the expression of MMP-8 and -9 in gingival tissues of diabetic chronic periodontitis (CP), non-diabetic CP, and healthy patients.

Wound healing potential of Cassia fistula on infected albino rat model.

Background: Infection is the major problem to treat the wound. Antibiotic resistance by the pathogenic microorganism renders drug ineffective and calls for improved designing and development of new drugs. New approach has been developed to isolate active components from botanicals.

Improved collagen bilayer dressing for the controlled release of drugs.

A novel bilayer dressing has been developed from bovine succinylated collagen. The dressing contains an antibiotic, Ciprofloxacin, for both immediate and time-regulated release for controlling the infection, as the infected open wounds need special care. The dressing consists of a sponge and a film, both prepared from succinylated bovine collagen.