Targeting efficiency and biodistribution of biotinylated-EGF-conjugated gelatin nanoparticles administered via aerosol delivery in nude mice with lung cancer Ching-Li Tseng, Steven Yueh-Hsiu Wu, Wen-Hsi Wang, Cheng-Liang Peng, Feng-Huei Lin * , Chien-Cheng Lin, Tai-Horng Young, Ming-Jium Shieh Institute of Biomedical Engineering, National Taiwan University, No.1, Section 1, Ren-ai Road, Taipei 100, Taiwan, ROC article info Article history: Received 19 December 2007 Accepted 11 March 2008 Available online 23 April 2008 Keywords: Nanoparticle Gelatin In vivo test Lung cancer Drug delivery EGF abstract Lung cancer is the most malignant cancer today; in order to develop an effective drug delivery system for lung cancer therapy, gelatin nanoparticles (GPs) were modified with NeutrAvidin FITC -biotinylated epidermal growth factor (EGF) to form EGF receptor (EGFR)-seeking nanoparticles (GP-Av-bEGF). Aerosol droplets of the GP-Av-bEGF were generated by using a nebulizer and were delivered to mice model of lung cancer via aerosol delivery. Analysis of the aerosol size revealed that 99% of the nanoparticles after nebulization had a mass median aerodynamic diameter (MMAD) within the suitable range (0.5–5 mm) for lower airway deposition. The safety of inhaled nanoparticles was examined by lung edema and myeloperoxidase (MPO) activity assay. There’s no finding suggestive of acute lung inflammation following inhalation. The fluorescence images obtained from live mice showed that the GP-Av-bEGF could target the cancerous lungs in a more specific manner. Fluorescence analysis of the organs revealed that the GP-Av-bEGF was mainly distributed in cancerous lungs. In contrast, nanoparticle accumulation was lower in normal lungs. The histological results indicated that the fluorescent GP-Av-bEGF was colocalized with the anti-EGFR-immunostain due to EGFR binding. The results of this study revealed that GP-Av-bEGF could target to the EGFR-overexpression cancer cells in vivo and may prove to be beneficial drug carriers when administered by simple aerosol delivery for the treatment of lung cancer. Ó 2008 Elsevier Ltd. All rights reserved. 1. Introduction Lung cancer is one of the most harmful forms of cancer. The long- term survival rate of lung cancer patients treated by conventional modalities such as surgical resection, radiation, and chemotherapy remains far from satisfactory. Systemic drug delivery is rarely suc- cessful because only a limited amount of the chemotherapeutic drug targets lung tumor sites, even when administered at a high dose [1]. Most of the chemotherapeutic drugs act on normal cells, inhibiting their growth; this makes the patient extremely weak and can even result in death. Therefore, accurate delivery of chemotherapeutic drugs to the tumor site is the most crucial step for increasing the survival rate of lung cancer patients. Intravenous (i.v.) injection of protein-based drugs and anticancer pharmaceuticals, with or without drug carriers, is the major delivery method employed for chemotherapy [2]. However, drugs encapsulated in nanocarrier were mostly accumulated in the reticuloendothelial system (RES) such as liver or spleen before they reach the intended target site [3]. The direct delivery of chemotherapeutic agents to the lungs offers a novel therapeutic approach for lung cancer patients. By the aerosol method, chemotherapeutic drugs can be efficiently and noninvasively delivered to lung cancer area by inhalation [4]. Thus, the drug can directly exert its effects on lung cancer cells before it is degraded or metabolized. Targeted aerosol delivery can also increase the retention time of the drug in the lungs; this improves the pulmonary receptor occupancy at the expense of systemic exposure, thereby reducing the systemic side effects of the drug [5,6]. In addition, this method could eliminate patient complaints associated with the daily administration employed in i.v. injection. Aerosol therapy employing a particulate drug carrier system is becoming a popular method for the delivery of therapeutic com- pounds. Although many materials have been used for constructing nanoparticles to serve as carriers for anticancer drugs, not all these materials have proved to be very promising when applied to the human body. Poly(lactic-co-glycolic acid) (PLGA) is a very common biodegradable polymer used for drug delivery. However, its biodegradation rate is extremely slow, and it is therefore unsuitable for pulmonary drug delivery, especially in cases where frequent dosing is required [7]. Leakage has always been a limitation of * Corresponding author. Tel.: þ886 2 23123456x1568; fax: þ886 2 23940049. E-mail address: double@ntu.edu.tw (F.-H. Lin). Contents lists available at ScienceDirect Biomaterials journal homepage: www.elsevier.com/locate/biomaterials Biomaterials 29 (2008) 3014–3022 Contents lists available at ScienceDirect Biomaterials journal homepage: www.elsevier.com/locate/biomaterials 0142-9612/$ – see front matter Ó 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.biomaterials.2008.03.033