ABSTRACT
Polydopamine (PDA) is a novel type of polymer synthesized inspired by adhesion proteins in mussels. It has been widely used in tumor-targeting drug delivery systems due to its natural advantages such as good biocompatibility, excellent photothermal conversion performance, adhesion, high chemical reactivity and multiple drug release response mechanisms. This review summarizes the applications of PDA-based tumor-targeting drug delivery in recent years, hoping to provide references for designing a more reasonable and effective PDA-based multifunctional collaborative tumor therapy platform.
ABSTRACT
Polymeric micelles which are self-assembled from amphiphilic copolymers are thermodynamically stable, and they can solubilize hydrophobic drugs by the hydrophilic core. Many excellent active compounds are confined because of general low oral bioavailability due to poor solubility. Take into account from the two points above, polymeric micelles may be used as proper oral carrier to improve the dissolubility of hydrophobic drugs, and enhance the permeation though gastrointestinal tract, therefore, the pharmacodynamics is elevated. Meanwhile, the segments in copolymers are multivariate, so many kinds of micelles can be obtained, such as, pH- or thermo- sensitive as well as mucoadhesive ones. The modified micelles can alter drug release profiles while solubilizing them, that is why the oral bioavailability increase further. In this review, recent progress of polymeric micelles used in oral administration is summarized, and the prospect of polymeric micelles' application in this field is also evaluated.
Subject(s)
Animals , Humans , Administration, Oral , Area Under Curve , Biological Availability , Drug Carriers , Drug Delivery Systems , Micelles , Pharmaceutical Preparations , Poloxamer , Chemistry , Polyethylene Glycols , Chemistry , Polymers , Chemistry , Risperidone , Pharmacokinetics , Silymarin , Pharmacokinetics , SolubilityABSTRACT
Microdialysis coupled with RP-HPLC was used to study the blood pharmacokinetics of pingyangmycin hydrochloride in rabbits. Supelco RP-amide C16 column was adopted for the analysis of pingyangmycin hydrochloride. The data was analyzed with 3P87 program. The calibration curve was linear in the concentration range from 1.04 to 66.56 microg x mL(-1) (r2 = 0.999 4). The in vivo recovery of microdialysis probe was (42.8 +/- 3.4)% (n = 4). The concentration-time curve of pingyangmycin hydrochloride was fitted to two-compartment model. T1/2 alpha and T1/2 beta were 14.9 and 60.3 min, respectively. The method is proved to be accurate, simple and suitable for the pharmacokinetics study of pingyangmycin hydrochloride in rabbits.
Subject(s)
Animals , Female , Male , Rabbits , Antibiotics, Antineoplastic , Blood , Pharmacokinetics , Area Under Curve , Bleomycin , Blood , Chemistry , Pharmacokinetics , Chromatography, High Pressure Liquid , Methods , Injections, Intravenous , Microdialysis , Methods , Molecular StructureABSTRACT
Meloxicam concentration in skin was determined following topical administration of meloxicam patches in hairless mouse. Samples were analysized by HPLC coupled with microdialysis sampling technique, in which in vivo recovery of probe was characterized by the retrodialysis method. It was indicated that the in vivo recovery of the probe was 14.0%. The range of steady state concentration of meloxicam in dialysate was 24-50 ng x mL(-1), and that was 170-360 ng x mL(-1) in the hairless mouse skin. Steady state concentration of meloxicam was reached shortly after the application of meloxicam patches, which was maintained during the period of experiment.
Subject(s)
Animals , Mice , Administration, Cutaneous , Chromatography, High Pressure Liquid , Cyclooxygenase 2 Inhibitors , Pharmacokinetics , Isoenzymes , Mice, Hairless , Mice, Inbred BALB C , Microdialysis , Skin , Metabolism , Skin Absorption , Thiazines , Pharmacokinetics , Thiazoles , PharmacokineticsABSTRACT
<p><b>AIM</b>To study chitosan-coated poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) on enhancing gastrointestinal absorption of insulin.</p><p><b>METHODS</b>Insulin-loaded PLGA multiple emulsions were prepared by a double-emulsion method. Using chitosan as a stabilizer, chitosan-coated PLGA-NPs was prepared. The changes of the morphology, size distribution and Zeta potential of the NPs were examined. The encapsulation efficiency was determined by HPLC. The release behaviors in vitro were assessed, and the hypoglycemic effects were evaluated by monitoring the glucose levels in diabetic rats.</p><p><b>RESULTS</b>Chitosan-coated PLGA-NPs showed a narrow size of distribution and regular surface with layer structure and their Zeta potential can be changed by chitosan. Chitosan-coating increased the encapsulation efficiency of insulin, reduced the initial burst and improved the release behavior of the NPs. About 14-16 h after intragastric administration of chitosan-coated INS-PLGA-NPs, the plasma glucose level decreased significantly compared with intragastric administration of same dose of non-coated NPs (P < or = 0.05), and the relative pharmacological availability was increased up to (15.4 +/- 1.2)%.</p><p><b>CONCLUSION</b>Chitosan-coated PLGA-NPs could enhance gastrointestinal absorption of insulin.</p>
Subject(s)
Animals , Male , Rats , Blood Glucose , Metabolism , Chitin , Pharmacology , Chitosan , Diabetes Mellitus, Experimental , Blood , Drug Carriers , Drug Delivery Systems , Hypoglycemic Agents , Pharmacokinetics , Pharmacology , Insulin , Pharmacokinetics , Pharmacology , Intestinal Absorption , Lactic Acid , Chemistry , Nanotechnology , Particle Size , Polyglycolic Acid , Chemistry , Polymers , Chemistry , Random Allocation , Rats, WistarABSTRACT
<p><b>AIM</b>To study the cutaneous permeation kinetics and pharmacodynamics of lidocaine gel.</p><p><b>METHODS</b>The concentration of lidocaine in dermis following topical application in rats was determined by the cutaneous microdialysis technique and related parameters were calculated; the pharmacodynamics of the gel was evaluated by electric stimulation method with EMLA (eutectic mixture of local anesthetics) cream as a control.</p><p><b>RESULTS</b>The peak of percutaneous absorption kinetic profile of lidocaine gel across rat skin occurred at 1.25 h; the onset time of local anesthetic action of lidociane gel was similar to that of EMLA, but both the duration and depth of anesthetic effect were superior to EMLA cream.</p><p><b>CONCLUSION</b>Lidocaine gel showed good anesthetic effect. The minimum effective concentration of lidocaine in dermis is 12 mg.L-1.</p>
Subject(s)
Animals , Male , Rats , Anesthesia, Local , Anesthetics, Local , Pharmacokinetics , Pharmacology , Gels , Lidocaine , Pharmacokinetics , Pharmacology , Pain Threshold , Prilocaine , Pharmacokinetics , Pharmacology , Random Allocation , Rats, Wistar , Skin AbsorptionABSTRACT
<p><b>AIM</b>To evaluate how solution viscosity affects the precorneal residence of five water-soluble polymers with different properties.</p><p><b>METHODS</b>Captive bubble technique was used, with the consecutive change of contact angle interpreted as an indication of desorption process, to study the residence of those polymers in vitro on freshly enucleated rabbit eyes under physiological conditions.</p><p><b>RESULTS</b>Carbopol and sodium hyaluronate (HA), which adsorbed to isolated ocular surface more than 15 min, showed the optimum precorneal retentive capabilities. When the solution viscosity increased from 12 mPa.s to 50 mPa.s, the residence time of carbopol and HA were prolonged 10 min and 7 min, respectively, but that of sodium carboxymethylcellulose was not affected.</p><p><b>CONCLUSION</b>The result suggested that higher viscosity is beneficial to improve the ocular residence time of bio-adhesive polymers.</p>