Explosive Crystallization of Urea Triggered by Focused Femtosecond Laser Irradiation

Abstract

The crystallization of urea was triggered using an intense 800 nm femtosecond laser that was focused to a supersaturated solution through an objective lens. An explosive crystallization proceeded in the entire sample glass tube for a few seconds at a concentration that no spontaneous nucleation occurred even after a few days. The crystallization was precisely monitored using a high-speed complementary metal oxide semiconductor (CMOS) camera attached to a microscope with a time resolution of 100 µs. On the basis of the results, the dynamic process of crystallization triggered by femtosecond laser ablation was discussed.

Small and Macromolecules Crystallization Induced by Focused Ultrafast Laser

“…The perturbation arising from these phenomena in the surrounding media near the focal point of the laser beam can trigger the nucleation. The present experimental observations are consistent with earlier studies in similar direction (Yoshikawa et al, 2006;Murai et al, 2011).…”

Influence of energy and wavelength on femtosecond laser-induced nucleation of protein

“…To date, light-induced nucleation has been demonstrated by optical Kerr effect [1][2][3][4][5][6][7][8], photon pressure [9,10], and photochemical reactions [11][12][13][14][15][16]. As another approach, we have proposed the focused irradiation of a femtosecond laser [17][18][19][20][21][22][23][24], whose peak intensity is $TW/cm 2 . In 2003, we reported enhanced nucleation of water-soluble proteins by the focused femtosecond laser irradiation of supersaturated solutions, under conditions where spontaneous nucleation rarely occurred [17].…”

“…It should be noted that the nucleation efficiency by the focused irradiation of a femtosecond laser is significantly higher than that by continuous wave and nanosecond lasers. We investigated the underlying mechanism of nucleation by fast imaging methods and revealed that the laser-induced cavitation bubbles locally concentrate a supersaturated solution at their surfaces, providing the conditions suitable for nucleation [18][19][20][21][22]. Owing to this direct trigger for nucleation, the femtosecond laser technique is very effective for various kinds of materials such as organic molecules [18], water-soluble proteins [17,[19][20][21], membrane proteins [23], and their complexes [25,26].…”

Femtosecond laser-induced nucleation of protein in agarose gel

“…The sudden pressure rise leads to an emission of a shock wave and bubbling, for example, the creation of cavitation bubbles by transient boiling [17][18][19][20] and subsequent long-lasting bubbles that are composed of gas products from the photodecomposition of solute and solvent molecules [21]. Recently, we and another group quantitatively determined threshold energies of nucleation and laser-induced bubbling using simple organic molecules and proteins [22][23][24][25]. The results clearly showed that nucleation occurs when the laser irradiation has energy above the threshold for the generation of laser-induced bubbling.…”