Study On Ciprofloxacin Chitosan Microspheres For Lung Targeting Drug Delivery

With the prevalence of tuberculosis in the world is worsening, the incidence ofMDR tuberculosis was also uptrend.China is high burden countries with TB, MDRtuberculosis epidemic is not optimistic. In the conditions of the lack of new drug fortuberculosis, modified of existing dosage form and administration route has beenpresent research focus,lung targeting drug delivery get more attention. Interventionaladministration with bronchoscopy is a safety and mature technology, and canaccurately control dosage, dugs is delivered to local focus of pneumonophthisis withbronchoscopy, especially for bronchial tuberculosis, MDR and chronic fibrocavernouspulmonary tuberculosis.Currently,effective concentration is short, drug-loadedsubstrate can’t be absorbed and implanted to distal bronchus. This article is intendedto develop a new dosage form that will be a exclusive drug for Bronchoscopy therapy,can degrade and be absorbed, and is safety for pulmonary delivery.In this study, drug carrier is chitosan, model drug is Ciprofloxacin, hydroxyethylcellulose[1-3]as a sustained-release microsphere excipients,glutaraldehyde crosslinkedmicrospheres are prepared for sustained release of Ciprofloxacin using chitosan.Microspheres were characterized by scanning electron microscopy(SEM)、UV andother detection means to evaluate its morphology, particle size distribution,encapsulation efficiency, drug-loaded, pulmonary retention, and accumulated release.To assess the feasibility of its bronchoscopic intervention therapy, in order to achievethe purpose of targeted therapy, improves anti-tuberculosis drugs ciprofloxacin releasetime in lung, reduces the frequency of administration and improves patients’compliance.PART ONE Preparation of Ciprofloxacin citosan microspheres Objective: To prepare sustained release Ciprofloxacin chitosan microspheres,whichcould be used in lung, and establish determination methond of Ciprofloxacin with UVspectrophotometry, and investigate influence factors in preparation process, andoptimize formulation and technology.Methods: drug carrier is chitosan,model drug is Ciprofloxacin,hydroxyethyl cellulose[1-3]as a sustained-release microsphere excipients,glutaraldehyde crosslinkedmicrospheres are prepared for sustained release of Ciprofloxacin using chitosan.Select drug loading and encapsulation efficiency as the evaluation index, orthogonalexperimental design Filter prescription process.Microspheres were characterized byscanning electron microscopy(SEM)、 UV and other detection means to evaluate itsmorphology, particle size distribution, encapsulation efficiency, drug-loaded,pulmonary retention, and accumulated release. Testing that Ciprofloxacin chitosanmicrospheres whether can be aspirated or injected by7＃needle or catheter.Result: The optimum formulation and technology is that chitosan mass fraction of2%,Cciprofloxacin and chitosan mass ratio of1:3, glutaraldehyde6%, the HEC massfraction of3%.Complete preparation of Ciprofloxacin chitosan microspheres Spheretype, smooth sphere, a small amount of folds, uniform particle size distribution in linewith the normal distribution, the average particle size (142.31±7.85) μm, the averagedrug loading was (36.23±0.42)%, with an average encapsulation efficiency (78.54±1.58)%, the average zeta potential value (51.68±2.3) mV.Microspheres can beinjected by7＃needle or catheter.Conclusion: Ciprofloxacin citosan microspheres is successfully prepared,characterization characteristics, Entrapment efficiency and drug loading are accordedwith requirement.PART TWO In vitro evaluation of Ciprofloxacin chitosan microspheresObjective:To investigate sustained release effect of Ciprofloxacin chitosanmicrospheres in vitro.Methods: By UV spectrophotometry method Ciprofloxacin chitosan microspheres invitro release test accurately weighed amount of drug-loaded microspheres into areactor equipped1ml PH7.4PBS dialysis bag, then placedwith stopper reagent bottle, PBS100ml of pH7.4as the release medium, the device on the rotational speed of100rpm, temperature (37±0.5)°C thermostat stirrer, regular sampling5ml, and iscomplementary to an equal volume of release medium, the first day of2h,4h,6h,8h,12h,16h,20h,24h,36h,48h,60h,72h sampling, sample after microporous (0.45μm)membrane filtration, detected by absorbance and calculate the concentration of thedrug.Result: As mass fraction of chitosan、glutaraldehyde and HEC increased, mass ratioof Ciprofloxacin and chitosan decreased, drug release rate was slower. Release time ofCiprofloxacin chitosan microspheres is6d in vitro. Accumulative release rate was49.3%in2d. Drug release was slowly stationary in2d-6d. Accumulative release ratewas95%in6d.Conclusion: Ciprofloxacin chitosan microspheres have better sustained release effectin vitro.PART THREE Safety evaluation of Ciprofloxacin chitosan microspheres usedin lungObjective: To observe solubility, permeability and absorption of Ciprofloxacinchitosan microspheres used in lung of new zealand white rabbits and beagle dogs.Methods：60rabbits are randomly divided into3groups,10in each group, controlgroup injected2ml physiological saline into left lung, blank microspheres groupinjected2ml blank microspheres(20mg) plus physiological saline into left lung, drugmicrospheres group injected2ml drug microspheres(20mg) plus physiological salineinto left lung.60dogs are randomly divided into3groups,20in each group, controlgroup injected5ml physiological saline into left lung, blank microspheres groupinjected5ml blank microspheres(300mg) plus physiological saline into left lung, drugmicrospheres group injected5ml drug microspheres(300mg) plus physiological salineinto left lung. For rabbits and dogs, body temperature and weight were detected;general conditions were observed; blood routine, T lymphocyte subsets and cytokine(IL-1β, IL-6, IL-8, IL-10, TNF-α) were detected after injecting1d,7d,14d; allanimals were sacrificed after injecting14d, and observed lung gross anatomy. Lungtissue of local injecting were evaluated by HE staining and immunohistochemistry (IL-1β, IL-6, IL-8, IL-10, TNF-α). For dogs bronchial mucosa was observed bybronchoscopy after injecting3d and7d. Respiratory rate, maximal expiratory pressureand minimal inspiratory pressure were observed by respiratory record instrumentbefore injecting to after injecting60min. Blood gas analysis were done after injecting1d,7d,14d. Lung tissue of local injecting were observed by SEM andTEM(transmission electron microscope).Result: Compared with control group in rabbits and dogs after injecting blank or drugmicrospheres, asphyxia and cough didn’t be found; general conditions were normal;body temperature and weight, blood routine and T lymphocyte didn’t showsignificantly diversity(P>0.05); lung gross anatomy didn’t show abnormal;histopathological examination showed that bronchiole didn’t obviously changed bycomparing with control group’s, and alveolus had complete structure and spacing ofalveolus was not incrassation; expression of IL-1β, IL-6, IL-8, IL-10and TNF-αdidn’t show significantly diversity in lung tissue of local injecting (P>0.05).For rabbits after injecting1d, content of IL-1β, IL-6, IL-8, IL-10and TNF-α ofcontrol group, blank microspheres and drug microspheres group were higher thanbefore injecting in blood; blank microspheres and drug microspheres were higher thancontrol group (P<0.05). After injecting7d, IL-1β, IL-6,IL-10and TNF-α of controlgroup didn’t show significantly diversity compared with before injecting(P>0.05);IL-8and IL-10of blank microspheres and drug microspheres didn’t showsignificantly diversity compared with before injecting(P>0.05); IL-1β, IL-6andTNF-α of blank microspheres and drug microspheres were higher than controlgroup(P<0.05). After injecting14d, except that IL-1β of blank microspheres groupwere higher than before injecting(P>0.05), others didn’t show significantly diversitycompared with before injecting(P>0.05). In dogs variations of cytokine were similarto that in rabbits.For dogs bronchial mucosa didn’t show abnormal, and no hyperemia, edema,induration and necrosis were found after injecting3d,7d by bronchoscopyobservation. Respiratory rate, maximal expiratory pressure and minimal inspiratorypressure didn’t show significantly diversity in control group, blank microspheres and drug microspheres group after immediate injecting(P>0.05), but Respiratory rate,minimal inspiratory pressure show significantly diversity after injecting10min(P<0.05), didn’t show significantly diversity after injecting30min(P>0.05).Blood gas analysis didn’t show significantly diversity in control group, blankmicrospheres and drug microspheres group after injecting1d,7d,14d(P>0.05). SEMand TEM didn’t show abnormal in in control group, blank microspheres and drugmicrospheres groupConclusion: Ciprofloxacin chitosan microspheres has better adhesion, and noinfluence on normal respiration, no irritation to bronchial mucosa, and can bedegraded and absorbed. Safty and feasibility of Ciprofloxacin chitosan microspheresused in lung are preliminariely confirmed.