在这份报告中,使用七种不同分离物的无细胞提取物合成金纳米颗粒(GNPS),即,产气假单胞菌CEBP2,假单胞菌。CEBP1,假单胞菌,肌动蛋白baumaniCEBS1,Cuprividussp。CEB3、藤黄微球菌CUB12和潘多拉菌。CUB2S.光谱(UV-vis,FTIR,DLS,XRD,EDS)和微观(FESEM,TEM)结果证实,在具有还原和自稳定活性的生物分子存在下,Au3还原为Au0。在这种绿色合成方法中,生物合成GNPS的平均粒径可能会有所不同(4-60nm),具体取决于细菌种类,培养基的pH值,孵化时间,和温度。在这项研究中,GSH修饰的BSGNP(Au-GSH)已显示出抗微生物活性,对革兰氏阳性细菌具有更好的稳定性。溶菌酶与Au-GSH(lyso@Au-GSH)缀合后,抑制区从12mm增强到23mm(Au-GSH)。TEM研究表明,球形GNP(16.65±2.84)与溶菌酶结合后,由于蛋白质冠的形成而变成花形GNP(22.22±3.12)。此外,将纳米生物缀合物(lyso@Au-GSH)与Nafion固定在玻璃碳电极上,以制造无标记阻抗生物传感器,该传感器对监测由于生物分子相互作用引起的换能器表面变化非常敏感。独特设计的生物传感器可以在3.0×101-3×1010cfumL-1的线性范围内选择性检测革兰氏阳性菌,RE<5%。所提出的最简单的生物传感器具有良好的重现性(RSD=3.1%)和优异的相关性(R2=0.999)与标准板计数方法,使其适用于监测生物流体中的革兰氏阳性细菌污染,食物,和环境样本。
In this report, gold nanoparticles (GNPS) were synthesized using cell-free extracts of seven different isolates, namely, Pseudomonas aerogenosa CEBP2, Pseudomonas sp. CEBP1, Pseudomonas pseudoalcaligenes CEB1G, Acinetobactor baumani CEBS1, Cuprividus sp. CEB3, Micrococcus luteus CUB12, and Pandoraea sp. CUB2S. The spectroscopic (UV-vis, FTIR, DLS, XRD, EDS) and microscopic (FESEM, TEM) results confirm the reduction of Au3+ to Au0 in the presence of biomolecules having reducing as well as self-stabilizing activity. In this green synthesis approach, the average particle size of biosynthesized GNPS might vary (4-60 nm) depending on the bacterial species, pH of the media, incubation time, and temperature. In this study, GSH-modified BSGNPs (Au-GSH) have shown antimicrobial activity with better stability against Gram-positive bacteria. After conjugation of lysozyme with Au-GSH (lyso@Au-GSH), the zone of inhibition was enhanced from 12 to 23 mm (Au-GSH). The TEM study shows the spherical GNP (16.65 ± 2.84) turns into a flower-shaped GNP (22.22 ± 3.12) after conjugation with lysozyme due to the formation of the protein corona. Furthermore, the nanobioconjugate (lyso@Au-GSH) was immobilized with Nafion on a glassy carbon electrode to fabricate a label-free impedance biosensor that is highly sensitive to monitor changes in the transducer surface due to biomolecular interactions. The uniquely designed biosensor could selectively detect Gram-positive bacteria in the linear range of 3.0 × 101-3 × 1010 cfu mL-1 with RE <5%. The proposed simplest biosensor exhibited good reproducibility (RSD = 3.1%) and excellent correlation (R2 = 0.999) with the standard plate count method, making it suitable for monitoring Gram-positive bacterial contamination in biofluids, food, and environmental samples.