Parikh Nidhi, Parekh Kinnari
Dr. K C Patel R & D Center, Charotar University of Science & Technology, Dist. Anand, Changa, 388 421, India.
J Mater Sci Mater Med. 2015 Jul;26(7):202. doi: 10.1007/s10856-015-5534-z. Epub 2015 Jul 8.
The paper describes the results of optimization of magnetic response for highly stable bio-functionalize magnetic nanoparticles dispersion. Concentration of gelatin during in situ co-precipitation synthesis was varied from 8, 23 and 48 mg/mL to optimize magnetic properties. This variation results in a change in crystallite size from 10.3 to 7.8 ± 0.1 nm. TEM measurement of G3 sample shows highly crystalline spherical nanoparticles with a mean diameter of 7.2 ± 0.2 nm and diameter distribution (σ) of 0.27. FTIR spectra shows a shift of 22 cm(-1) at C=O stretching with absence of N-H stretching confirming the chemical binding of gelatin on magnetic nanoparticles. The concept of lone pair electron of the amide group explains the mechanism of binding. TGA shows 32.8-25.2% weight loss at 350 °C temperature substantiating decomposition of chemically bind gelatin. The magnetic response shows that for 8 mg/mL concentration of gelatin, the initial susceptibility and saturation magnetization is the maximum. The cytotoxicity of G3 sample was assessed in Normal Rat Kidney Epithelial Cells (NRK Line) by MTT assay. Results show an increase in viability for all concentrations, the indicative probability of a stimulating action of these particles in the nontoxic range. This shows the potential of this technique for biological applications as the coated particles are (i) superparamagnetic (ii) highly stable in physiological media (iii) possibility of attaching other drug with free functional group of gelatin and (iv) non-toxic.
本文描述了用于高度稳定的生物功能化磁性纳米颗粒分散体的磁响应优化结果。原位共沉淀合成过程中明胶的浓度在8、23和48mg/mL之间变化,以优化磁性能。这种变化导致微晶尺寸从10.3nm变为7.8±0.1nm。G3样品的透射电子显微镜测量显示出高度结晶的球形纳米颗粒,平均直径为7.2±0.2nm,直径分布(σ)为0.27。傅里叶变换红外光谱显示C=O伸缩振动处有22cm(-1)的位移,且不存在N-H伸缩振动,这证实了明胶与磁性纳米颗粒的化学结合。酰胺基团孤对电子的概念解释了结合机制。热重分析表明,在350℃温度下重量损失为32.8 - 25.2%,证实了化学结合的明胶发生了分解。磁响应表明,对于8mg/mL浓度的明胶,初始磁化率和饱和磁化强度最大。通过MTT法在正常大鼠肾上皮细胞(NRK系)中评估了G3样品的细胞毒性。结果显示所有浓度下细胞活力均增加,表明这些颗粒在无毒范围内具有刺激作用的可能性。这表明了该技术在生物应用方面的潜力,因为包被的颗粒具有(i)超顺磁性(ii)在生理介质中高度稳定(iii)能够通过明胶的游离官能团连接其他药物以及(iv)无毒的特性。