* President-elect Humala to be sworn in July 28
* Brother's Russia scandal hurts Humala's popularity
LIMA, July 17 (Reuters) - Peru's President-elect Ollanta Humala has taken a hard fall in popularity after suspending his brother from his political coalition over ethics concerns, according to an Ipsos Apoyo poll published on Sunday.
His rating plummeted 29 points to 41 percent just days before his July 28 inauguration, according to the survey, which appeared in El Comercio newspaper. The previous Ipsos Apoyo poll, which came out on June 19, had Humala at 70 percent.
Earlier this month Humala cut political ties with his brother, Alexis Humala, after he flew to Russia to meet with Gazprom executives about investing in Peru's gas fields.
Local newspapers said the July 5 meeting reeked of nepotism after communiques by Gazprom and Russia's foreign ministry said Alexis Humala was sent as a "special representative" of the president-elect.
But the president-elect, who campaigned as an anti-corruption crusader, said his brother went to Moscow without his knowledge to angle for business with the world's largest natural gas company, state-controlled Gazprom.
"The scandal over Alexis' trip to Moscow has cost Ollanta Humala a fall of 29 points in his approval rating," Ipsos Apoyo director Alfredo Torres told El Comercio.
The poll had a margin of error of 4.4 percentage points in the capital Lima and 2.8 percent in other areas of the country.
Alexis Humala attended a university in Russia and lived there for many years.
President-elect Humala, a leftist who has promised to govern as a moderate, has not announced who will serve in key cabinet positions. This, according to analysts, is another negative factor that has been pressuring his rating. (Reporting by Patricia Velez, writing by Hugh Bronstein; Editing by Christopher Wilson)