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April 26, 2019 | A version of this story appeared in Volume 97, Issue 17


Letters to the editor


Contaminated stir bars

A photo of a collection of dirty magnetic stir bars.
Credit: ACS Catal.
Dirty magnetic stir bars

As I read the article on contamination and by-product generation when dirty or damaged magnetic paddles are used in organic synthesis (C&EN, April 1, page 12), it struck me that it is very similar to the pathogenic microbes sticking to public phones used in the earlier days in the hospital wards.

I am an organic chemist with over 30 years of experience in research, developing technologies for the industry, and almost 14 years in teaching, helping set up labs, training research workers, etc. This aspect of contamination is neglected and deserves all the attention, particularly when we are working on the milligram scale.

I was avoiding using damaged Teflon stir bars—one could say “brahmanical cleaning” was our practice! I would rather use a glass-encapsulated stir bar for very small-scale operations.

It is a simple soaking in appropriate acid that would remove the metal particles adhering to the Teflon stir paddle.

We used to rub the Teflon paddle against a chamois leather or fine sandpaper if it became dirty.

M. Bapuji
Hyderabad, India


Analytical thoughts on succinic acid

Michael McCoy’s essay “The Final Chapter for Succinic Acid” (C&EN, March 25, page 15) motivated me to share some insights on my career from the viewpoint of an analytical chemist. The time period was the year 1990. Early in the year I experienced a job layoff. I exited from the mission of a specific analytical laboratory. Later that year, I was employed at a different analytical laboratory (in a different state in the US) with a very different mission. I quantitated priority pollutant organics from environmental samples in the first lab and changed to quantifying mono- and dicarboxylic acids from fermentation media in the second lab. Succinic acid was one of those analytes. The first lab was an Environmental Protection Agency contract lab, while the second lab supported a biotech engineering initiative. Needless to say, this biotech initiative was less competitive with other biotech initiatives even back then.

Paul R. Loconto
Okemos, Michigan


Artificial intelligence helping chemists

I read with interest “Artificial Intelligence Could Assist Chemists with Disabilities” in the March 18 edition of C&EN (page 16). Artificial intelligence is clearly a very promising tool to improve accessibility for chemists with disabilities.

AI has the potential to make chemistry more accessible to blind chemists and chemistry students. Members of the American Chemical Society Committee on Nomenclature, Terminology, and Symbols (NTS) have been working for 2 years with a committee of chemists from the Braille Authority of North America (BANA) to update the Braille Code for Chemical Notation 1997. An objective of revising the code is to make chemistry more accessible to blind students. Updating the hard-copy braille code and tactile graphics will expand all blind chemists’ accessibility. Advances in technology will make braille products more available.

The diversity work that NTS is doing has attracted the attention of the International Union of Pure and Applied Chemistry (IUPAC). The secretary general of IUPAC sat in on a braille code discussion by NTS members in August 2018 in Boston.

A related project that has been brought to the attention of NTS is an attempt by some publishers to provide standard symbols and notation in EPUB products. At present several blind chemists and several EPUB publishers are working to standardize the EPUB chemistry format. This group has requested assistance from NTS to develop standardized chemistry symbols and notation.

ACS continues to strive for diversity. Much work has been done; more work needs to be done. Access to AI systems could improve opportunities for a more diverse chemist population.

Philip Verhalen
Scottsville, Texas


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