Atomic Force Microscopy-Based Force Spectroscopy …
601
lysozyme antibody-functionalized tip and adsorbed lysozyme on mica sheet, Kienberger et al. used a combination of highly accurate and precise AFM-FS together
with topographical imaging that is also termed as force-volume mode [31].
8.4 Application in Metallic Ions Sensing
Some metallic ions are known to cause both environmental and health hazards. The
newly developed method for the identification of these toxic metal ions is AFMSMFS. The development of a new AFM-SMFS-based aptasensor capable of detecting
mercury ions (Hg
2+ ) down to sub-nM concentration is indicated in the previous study
[68]. This novel technique could be exploited for detection/sensing of other polluting
metal ions.
9 Pros and Cons
Pros:
(a) These force spectroscopies are very sensitive and precise technique.
(b) These force spectroscopies could be exploited for range of applications.
(c) These force spectroscopy measurements are not time consuming.
Cons:
(a) For Young’s modulus measurement of biological sample like cells these force
spectroscopies are largely dominated by capillary forces which can be overcome
by using fluid cell.
(b) These force spectroscopies measurements require calibration and other values
(Spring constant) that sometimes differs from manufacturer’s value.
(c) These force spectroscopies need to be performed in a very controlled environment to have reproducible results.
10 Conclusions and Future Prospective
The above discussed examples prove that AFM-FS and SMFS technique is very
useful and powerful tool for investigating the molecular recognition and interactions. The AFM-FS and AFM-SMFS techniques will generate growing interest
among various scientists with different backgrounds for biosensing and bioimaging
applications in the future also. The progress in bioimaging and biosensing by AFM
could be further improved from the combinatorial development of nanotechnology,
biomedical engineering, and materials science. Further developments in SMFS for
601
lysozyme antibody-functionalized tip and adsorbed lysozyme on mica sheet, Kienberger et al. used a combination of highly accurate and precise AFM-FS together
with topographical imaging that is also termed as force-volume mode [31].
8.4 Application in Metallic Ions Sensing
Some metallic ions are known to cause both environmental and health hazards. The
newly developed method for the identification of these toxic metal ions is AFMSMFS. The development of a new AFM-SMFS-based aptasensor capable of detecting
mercury ions (Hg
2+ ) down to sub-nM concentration is indicated in the previous study
[68]. This novel technique could be exploited for detection/sensing of other polluting
metal ions.
9 Pros and Cons
Pros:
(a) These force spectroscopies are very sensitive and precise technique.
(b) These force spectroscopies could be exploited for range of applications.
(c) These force spectroscopy measurements are not time consuming.
Cons:
(a) For Young’s modulus measurement of biological sample like cells these force
spectroscopies are largely dominated by capillary forces which can be overcome
by using fluid cell.
(b) These force spectroscopies measurements require calibration and other values
(Spring constant) that sometimes differs from manufacturer’s value.
(c) These force spectroscopies need to be performed in a very controlled environment to have reproducible results.
10 Conclusions and Future Prospective
The above discussed examples prove that AFM-FS and SMFS technique is very
useful and powerful tool for investigating the molecular recognition and interactions. The AFM-FS and AFM-SMFS techniques will generate growing interest
among various scientists with different backgrounds for biosensing and bioimaging
applications in the future also. The progress in bioimaging and biosensing by AFM
could be further improved from the combinatorial development of nanotechnology,
biomedical engineering, and materials science. Further developments in SMFS for