Green synthesis of silver nanoparticles using Ixora coccinea leaves extract Muthu Karuppiah a,n , Rangasamy Rajmohan b a Department of Chemistry, Manonmaniam Sundaranar University, Tirunelveli 627012, TN, India b Regional Plant Quarantine Station, Directorate of Plant Protection, Quarantine and Storage, Ministry of Agriculture, Government of India, Meenambakkam, Chennai 600027, TN, India article info Article history: Received 15 October 2012 Accepted 19 January 2013 Available online 25 January 2013 Keywords: Green synthesis Ixora coccinea Silver nanoparticles abstract Biologically dependable processes for the green synthesis of silver nanoparticles (Ag NPs) were developed in nanoscience and nanotechnology. In this present paper, green synthesis of Ag NPs was performed from aqueous silver nitrate using the fresh Ixora coccinea L., leaves extract. The formation of Ag NPs was observed by the change of color from colorless to dark brown by the addition of silver nitrate into leaves extract. The synthesized Ag NPs were characterized by UV–vis, FTIR and XRD analyses. Further, the size and shapes of Ag NPs were identified by field emission scanning electron microscope (FESEM) technique to obtain particle sizes in the range from 13 to 57 nm. & 2013 Elsevier B.V. All rights reserved. 1. Introduction Nanoscience and nanotechnology has seen major development in the bio-fabrication process of metal nanoparticles (MNPs) [1]. The MNPs are broadly applied in the science and technology such as medicine, biology, biotechnology, chemistry, physics, catalysis, electronics and material sciences. Green synthesis of MNPs is an economic, eco-friendly and simple method in the synthesis route [2]. A number of bio-molecules act as reducing and protecting agents in the green synthesis of MNPs. Green/biosynthesis of MNPs was performed by using bacteria [3,4], fungi [5] and plant [6–8] extract. Geranium leaf extract has been used for the biosynthesis of Ag NPs with particles size from 16 to 40 nm [9]. The aqueous extract of Acalypha indica leaf acts as a good reducing agents for the biosynthesis of Ag NPs with the particles size from 20 to 30 nm and used in antibacterial activity [10]. Black Tea leaf extract was used in the biogenic synthesis of Ag and Au NPs and the particles size was approximately 20 nm with the shapes of nano-prisms, nano-rods and nano-trapezoids [11]. In the present research work, we report the green synthesis of Ag NPs by using Ixora coccinea leaves extract. I. coccinea (family: Rubiaceae) was gen- erally used as a traditional medicinal plant [12]. The plant leaves, flower, and roots have been used in traditional medicine for the treatment of a variety of infections, hypertension, menstrual irregularities, sprains, chronic ulcers and skin diseases [13] 2. Experimental methods Healthy leaves of I. coccinea were collected from the campus of Manonmaniam Sundaranar University, Tirunelveli, Tamil Nadu, India. AgNO 3 was purchased from E-Merck India Ltd. The freshly collected leaves of I. coccinea (12 g) were thoroughly washed with running tap water followed by ultra-pure deionized water to remove the filth. The cleaned leaves were taken in a 250 mL Erlenmeyer flask; 100 mL of triply distilled water was added and boiled at 80 1C for 5 min. The leaf extract was filtered through Whatman’s No. 1 filter paper and the obtained filtrate was stored at 4 1C for further use for the green synthesis of Ag NPs. In this study, the leaves extract acts as a reducing and protecting agent for the green synthesis of Ag NPs. In a typical synthesis of Ag NPs, 0.5 mL of I. coccinea leaves extract was added to 10 mL of 1 mM AgNO 3 aqueous solution and kept in a dark place at room temperature. After few minutes, the colorless reaction mixture changed to dark brown color which indicates the formation of Ag NPs. The bio-reduced Ag NPs were monitored by using a UV–vis spectrophotometer. The UV–vis spectra was recorded on a Perkin-Elmer (Lambda 25 Model) UV–vis spectrophotometer and the sample was measured in the wave- length region of 200–800 nm. The morphological studies of the synthesized Ag NPs were viewed by FESEM (HITACHI SU-6600 model) instrument. The green synthesized Ag NPs were centrifuged at 10,000 rpm for 15 min to obtain the residue. The residual part of Ag NPs was washed with deionized water and dried in a hot air oven at 60 1C for 24 h. The powdered Ag NPs were analyzed by a Bruker model D8 advanced powder X-ray diffractometer. The intensity data for the lyophilized nanosilver powder were collected in the 2y range 20–801 and the scanning speed at 0.02 min per degree. The green synthesis of Ag NPs was recorded by JASCO FTIR spectrophotometer Contents lists available at SciVerse ScienceDirect journal homepage: www.elsevier.com/locate/matlet Materials Letters 0167-577X/$ - see front matter & 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.matlet.2013.01.087 n Corresponding author. Tel.: þ91 99626 73910; fax: þ91 462 2334363. E-mail addresses: karu.muthu@yahoo.com, mkm8477@gmail.com (M. Karuppiah). Materials Letters 97 (2013) 141–143