Machine-Free Polymerase Chain Reaction with Triangular Gold and Silver Nanoparticles

Abstract

Photothermal effects of metal nanoparticles (NPs) are used for various biotechnological applications. Although NPs have been used in a polymerase chain reaction (PCR), the effects of shape on the photothermal properties and its efficiency on PCR are less explored. The present study reports the synthesis of triangular gold and silver NPs, which can attain temperatures up to ∼90 °C upon irradiation with 808 nm laser. This photothermal property of synthesized nanoparticles was evaluated using various concentrations, irradiation time, and power to create a temperature profile required for variable-temperature PCR. This study reports a cost-effective, machine-free PCR using both gold and silver triangular NPs, with efficiency similar to that of a commercial PCR machine. Interestingly, addition of triangular NPs increases PCR efficiency in commercial PCR reactions. The higher PCR efficiencies are due to the direct binding and unfolding of double-stranded DNA as suggested by circular dichroism and UV spectroscopy. These findings suggest that triangular NPs can be used to develop cost-effective, robust machine-free PCR modules and can be used in various other photothermal applications.

Charge and hydrophobicity of amyloidogenic protein/peptide templates regulate the growth and morphology of gold nanoparticles

“…1f ). 42,43 In contrast, when a similar reaction was performed with protein prepared at pH 2.5, a dramatic change in the morphology of NPs was observed when templated with amyloid fibrils. In this case, predominantly small spherical shape NPs, self-assembled into AuSSs 44 were observed (Fig.…”

“…S7b †). 42 To exclude the possibility that at different pHs or during nanocrystal formation, the structure of amyloid fibrils might alter, which in turn may promote different morphological growth of AuNPs, we analyzed the X-ray diffraction of amyloid fibrils. We examined the diffraction patterns before and after the formation of AuTNPs and AuSSs.…”

“…Differently shaped AuNPs are well known for their optical, photonic, and plasmonic enhancement applications, such as surface-enhanced Raman scattering (SERS), 62 photothermal properties, 42,63 and sensing. 64 The amyloids can fine-tune the shape and size of the AuTNPs and AuSSs for diverse applications.…”

Application of Nanomaterials to Enhance Polymerase Chain Reaction

“…For example, Au NPs are characterized by adjustable size and physical size, catalytic activity, high surface volume ratio, high stability, easy synthesis and surface modification, and strong light absorption and scattering properties [5,14]. Figure 1 shows transmission electron microscopy (TEM) images of Au NPs in different morphologies [15,16]. Li et al for the first time reported the optimization of Au NPs on PCR.…”

A sample-to-answer DNA detection microfluidic system integrating sample pretreatment and smartphone-readable gradient plasmonic photothermal continuous-flow PCR

“…9,10 Therefore, full-process PCR analysis consumes 1.5-3 hours and relies on bulky equipment and trained professionals, thus requiring systematic optimization for speed, workflow, equipment economy, and convenience. 2,9 Therefore, researchers recently proposed the fusion of microfluidics, 11 fast PCR or isothermal amplification methods, 12 and nanomaterials [13][14][15] to reduce the amplification time and economize devices, 16 and even integrate all processes into one system, giving birth to a "sample-to-answer" concept. 9,[16][17][18][19] For instance, Sumit Kalsi performed microvolume reagent operation and fluorescence recombinase polymerase amplification (RPA) based on an electrowetting on a dielectric-based (EWOD) microfluidic platform and a specialized CCD-based detection device.…”